Merge remote-tracking branch 'origin/main' into claude/focused-poincare-26165a

# Conflicts:
#	docs/INDEX.md

__tests__/actions/active-sprint-action.test.ts

@@ -0,0 +1,103 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('next/cache', () => ({ revalidatePath: vi.fn() }))
+vi.mock('next/headers', () => ({
+  cookies: vi.fn().mockResolvedValue({
+    set: vi.fn(),
+    get: vi.fn(),
+    delete: vi.fn(),
+  }),
+}))
+vi.mock('iron-session', () => ({
+  getIronSession: vi.fn().mockResolvedValue({ userId: 'user-1', isDemo: false }),
+}))
+vi.mock('@/lib/session', () => ({
+  sessionOptions: { cookieName: 'test', password: 'test' },
+}))
+vi.mock('@/lib/product-access', () => ({
+  productAccessFilter: vi.fn().mockReturnValue({}),
+}))
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    sprint: { findFirst: vi.fn() },
+    product: { findFirst: vi.fn() },
+    user: {
+      findUnique: vi.fn(),
+      update: vi.fn().mockResolvedValue({}),
+    },
+    $executeRaw: vi.fn().mockResolvedValue(1),
+  },
+}))
+
+import { prisma } from '@/lib/prisma'
+import { clearActiveSprintAction } from '@/actions/active-sprint'
+
+const mockPrisma = prisma as unknown as {
+  product: { findFirst: ReturnType<typeof vi.fn> }
+  user: {
+    findUnique: ReturnType<typeof vi.fn>
+    update: ReturnType<typeof vi.fn>
+  }
+}
+
+describe('clearActiveSprintAction', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('writes null instead of deleting the key', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce({ id: 'p1' })
+    mockPrisma.user.findUnique.mockResolvedValueOnce({
+      settings: { layout: { activeSprints: { p1: 'sprint-1', p2: 'sprint-2' } } },
+    })
+
+    const result = await clearActiveSprintAction('p1')
+
+    expect(result).toEqual({ success: true })
+    const updateArg = mockPrisma.user.update.mock.calls[0][0] as {
+      data: { settings: { layout?: { activeSprints?: Record<string, string | null> } } }
+    }
+    expect(updateArg.data.settings.layout?.activeSprints).toEqual({
+      p1: null,
+      p2: 'sprint-2',
+    })
+  })
+
+  it('preserves other product keys when clearing one', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce({ id: 'p1' })
+    mockPrisma.user.findUnique.mockResolvedValueOnce({
+      settings: {
+        layout: {
+          activeSprints: { p1: 'sprint-1', p2: 'sprint-2', p3: null },
+        },
+      },
+    })
+
+    await clearActiveSprintAction('p1')
+
+    const updateArg = mockPrisma.user.update.mock.calls[0][0] as {
+      data: { settings: { layout?: { activeSprints?: Record<string, string | null> } } }
+    }
+    expect(updateArg.data.settings.layout?.activeSprints).toEqual({
+      p1: null,
+      p2: 'sprint-2',
+      p3: null,
+    })
+  })
+
+  it('rejects when product is not accessible', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce(null)
+
+    const result = await clearActiveSprintAction('p1')
+
+    expect(result).toEqual({ error: 'Product niet gevonden of niet toegankelijk' })
+    expect(mockPrisma.user.update).not.toHaveBeenCalled()
+  })
+
+  it('rejects invalid productId', async () => {
+    const result = await clearActiveSprintAction('')
+
+    expect(result).toEqual({ error: 'Ongeldig product-id' })
+    expect(mockPrisma.user.update).not.toHaveBeenCalled()
+  })
+})

__tests__/actions/commit-sprint-membership.test.ts

@@ -0,0 +1,290 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('next/cache', () => ({ revalidatePath: vi.fn() }))
+vi.mock('next/headers', () => ({
+  cookies: vi.fn().mockResolvedValue({
+    set: vi.fn(),
+    get: vi.fn(),
+    delete: vi.fn(),
+  }),
+}))
+vi.mock('iron-session', () => ({
+  getIronSession: vi.fn().mockResolvedValue({ userId: 'user-1', isDemo: false }),
+}))
+vi.mock('@/lib/session', () => ({
+  sessionOptions: { cookieName: 'test', password: 'test' },
+}))
+vi.mock('@/lib/product-access', () => ({
+  productAccessFilter: vi.fn().mockReturnValue({}),
+  getAccessibleProduct: vi.fn().mockResolvedValue({ id: 'product-1' }),
+}))
+vi.mock('@/lib/rate-limit', () => ({
+  enforceUserRateLimit: vi.fn().mockReturnValue(null),
+}))
+vi.mock('@/lib/code-server', () => ({
+  createWithCodeRetry: vi.fn(),
+  generateNextSprintCode: vi.fn(),
+}))
+vi.mock('@/lib/active-sprint', () => ({
+  setActiveSprintInSettings: vi.fn().mockResolvedValue(undefined),
+}))
+vi.mock('@/lib/prisma', () => {
+  const txClient = {
+    sprint: { create: vi.fn() },
+    story: { updateMany: vi.fn() },
+    task: { updateMany: vi.fn() },
+  }
+  return {
+    prisma: {
+      sprint: { findFirst: vi.fn() },
+      story: {
+        findMany: vi.fn(),
+        updateMany: vi.fn(),
+      },
+      task: {
+        findMany: vi.fn(),
+        updateMany: vi.fn(),
+      },
+      $transaction: vi.fn(async (fn: (tx: typeof txClient) => unknown) => fn(txClient)),
+      __txClient: txClient,
+    },
+  }
+})
+
+import { prisma } from '@/lib/prisma'
+import { commitSprintMembershipAction } from '@/actions/sprints'
+
+type Mocked = {
+  sprint: { findFirst: ReturnType<typeof vi.fn> }
+  story: {
+    findMany: ReturnType<typeof vi.fn>
+    updateMany: ReturnType<typeof vi.fn>
+  }
+  task: {
+    findMany: ReturnType<typeof vi.fn>
+    updateMany: ReturnType<typeof vi.fn>
+  }
+  $transaction: ReturnType<typeof vi.fn>
+  __txClient: {
+    sprint: { create: ReturnType<typeof vi.fn> }
+    story: { updateMany: ReturnType<typeof vi.fn> }
+    task: { updateMany: ReturnType<typeof vi.fn> }
+  }
+}
+const mockPrisma = prisma as unknown as Mocked
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  mockPrisma.sprint.findFirst.mockReset().mockResolvedValue({
+    id: 'sprint-active',
+    product_id: 'product-1',
+  })
+  mockPrisma.story.findMany.mockReset()
+  mockPrisma.story.updateMany.mockReset()
+  mockPrisma.task.findMany.mockReset()
+  mockPrisma.task.updateMany.mockReset()
+  mockPrisma.$transaction.mockImplementation(
+    async (fn: (tx: typeof mockPrisma.__txClient) => unknown) =>
+      fn(mockPrisma.__txClient),
+  )
+  mockPrisma.__txClient.story.updateMany.mockReset().mockResolvedValue({ count: 0 })
+  mockPrisma.__txClient.task.updateMany.mockReset().mockResolvedValue({ count: 0 })
+})
+
+describe('commitSprintMembershipAction', () => {
+  it('happy path: eligible adds + valid removes → transactie commits', async () => {
+    // adds-partition: alle eligible (sprint_id=null + niet DONE)
+    mockPrisma.story.findMany
+      // partition lookup
+      .mockResolvedValueOnce([
+        { id: 's-add-1', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      // removes-filter (sprint_id == activeSprintId)
+      .mockResolvedValueOnce([{ id: 's-rem-1' }])
+      // affectedStories
+      .mockResolvedValueOnce([
+        { pbi_id: 'pbiA' },
+        { pbi_id: 'pbiB' },
+      ])
+    mockPrisma.task.findMany.mockResolvedValueOnce([{ id: 't1' }])
+
+    const result = await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: ['s-add-1'],
+      removes: ['s-rem-1'],
+    })
+
+    expect('success' in result).toBe(true)
+    if ('success' in result) {
+      expect(result.affectedStoryIds.sort()).toEqual(['s-add-1', 's-rem-1'])
+      expect(result.affectedPbiIds.sort()).toEqual(['pbiA', 'pbiB'])
+      expect(result.affectedTaskIds).toEqual(['t1'])
+      expect(result.conflicts.notEligible).toEqual([])
+      expect(result.conflicts.alreadyRemoved).toEqual([])
+    }
+    expect(mockPrisma.$transaction).toHaveBeenCalledTimes(1)
+    expect(mockPrisma.__txClient.story.updateMany).toHaveBeenCalledTimes(2)
+    expect(mockPrisma.__txClient.task.updateMany).toHaveBeenCalledTimes(2)
+  })
+
+  it('add met status=DONE → conflicts.notEligible, story niet ge-update', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([
+        { id: 's-done', sprint_id: null, status: 'DONE', sprint: null },
+      ])
+      // removes-filter (geen removes)
+      .mockResolvedValueOnce([])
+
+    const result = await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: ['s-done'],
+      removes: [],
+    })
+
+    expect('success' in result).toBe(true)
+    if ('success' in result) {
+      expect(result.affectedStoryIds).toEqual([])
+      expect(result.conflicts.notEligible).toEqual([
+        { storyId: 's-done', reason: 'DONE' },
+      ])
+    }
+    // Geen transaction omdat er niets te commiten valt.
+    expect(mockPrisma.$transaction).not.toHaveBeenCalled()
+  })
+
+  it('add met sprint_id in andere OPEN sprint → conflicts.notEligible IN_OTHER_SPRINT', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([
+        {
+          id: 's-elsewhere',
+          sprint_id: 'sprint-other',
+          status: 'IN_SPRINT',
+          sprint: { id: 'sprint-other', code: 'SP-O', status: 'OPEN' },
+        },
+      ])
+      .mockResolvedValueOnce([])
+
+    const result = await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: ['s-elsewhere'],
+      removes: [],
+    })
+
+    if ('success' in result) {
+      expect(result.conflicts.notEligible).toEqual([
+        { storyId: 's-elsewhere', reason: 'IN_OTHER_SPRINT' },
+      ])
+    }
+  })
+
+  it('remove voor story die niet in actieve sprint zit → conflicts.alreadyRemoved', async () => {
+    mockPrisma.story.findMany
+      // adds-partition (geen adds)
+      .mockResolvedValueOnce([])
+      // removes-filter — race scenario: story zit niet meer in active sprint
+      .mockResolvedValueOnce([])
+
+    const result = await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: [],
+      removes: ['s-was-removed'],
+    })
+
+    if ('success' in result) {
+      expect(result.affectedStoryIds).toEqual([])
+      expect(result.conflicts.alreadyRemoved).toEqual(['s-was-removed'])
+    }
+  })
+
+  it('transactie: story.status=IN_SPRINT bij add, =OPEN bij remove', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([
+        { id: 's-add', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      .mockResolvedValueOnce([{ id: 's-rem' }])
+      .mockResolvedValueOnce([{ pbi_id: 'pbiA' }])
+    mockPrisma.task.findMany.mockResolvedValueOnce([])
+
+    await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: ['s-add'],
+      removes: ['s-rem'],
+    })
+
+    const calls = mockPrisma.__txClient.story.updateMany.mock.calls
+    // Add: status=IN_SPRINT + sprint_id=sprint-active
+    expect(calls[0][0].data).toEqual({
+      sprint_id: 'sprint-active',
+      status: 'IN_SPRINT',
+    })
+    // Remove: status=OPEN + sprint_id=null
+    expect(calls[1][0].data).toEqual({ sprint_id: null, status: 'OPEN' })
+  })
+
+  it('task.sprint_id wordt in dezelfde transactie ge-update', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([
+        { id: 's-add', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      .mockResolvedValueOnce([])
+      .mockResolvedValueOnce([{ pbi_id: 'pbiA' }])
+    mockPrisma.task.findMany.mockResolvedValueOnce([])
+
+    await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: ['s-add'],
+      removes: [],
+    })
+
+    expect(mockPrisma.__txClient.task.updateMany).toHaveBeenCalledWith(
+      expect.objectContaining({
+        where: { story_id: { in: ['s-add'] } },
+        data: { sprint_id: 'sprint-active' },
+      }),
+    )
+  })
+
+  it('return: affectedStoryIds + affectedPbiIds + affectedTaskIds + conflicts', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([
+        { id: 's-add', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      .mockResolvedValueOnce([{ id: 's-rem' }])
+      .mockResolvedValueOnce([
+        { pbi_id: 'pbiA' },
+        { pbi_id: 'pbiB' },
+      ])
+    mockPrisma.task.findMany.mockResolvedValueOnce([
+      { id: 't1' },
+      { id: 't2' },
+    ])
+
+    const result = await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: ['s-add'],
+      removes: ['s-rem'],
+    })
+
+    expect(result).toMatchObject({
+      success: true,
+      affectedStoryIds: expect.arrayContaining(['s-add', 's-rem']),
+      affectedPbiIds: expect.arrayContaining(['pbiA', 'pbiB']),
+      affectedTaskIds: expect.arrayContaining(['t1', 't2']),
+    })
+  })
+
+  it('rejects when sprint is not accessible', async () => {
+    mockPrisma.sprint.findFirst.mockResolvedValue(null)
+
+    const result = await commitSprintMembershipAction({
+      activeSprintId: 'sprint-active',
+      adds: [],
+      removes: [],
+    })
+
+    expect('error' in result).toBe(true)
+    if ('error' in result) {
+      expect(result.code).toBe(403)
+    }
+  })
+})

__tests__/actions/create-sprint-with-selection.test.ts

@@ -0,0 +1,300 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('next/cache', () => ({ revalidatePath: vi.fn() }))
+vi.mock('next/headers', () => ({
+  cookies: vi.fn().mockResolvedValue({
+    set: vi.fn(),
+    get: vi.fn(),
+    delete: vi.fn(),
+  }),
+}))
+vi.mock('iron-session', () => ({
+  getIronSession: vi.fn().mockResolvedValue({ userId: 'user-1', isDemo: false }),
+}))
+vi.mock('@/lib/session', () => ({
+  sessionOptions: { cookieName: 'test', password: 'test' },
+}))
+vi.mock('@/lib/product-access', () => ({
+  productAccessFilter: vi.fn().mockReturnValue({}),
+  getAccessibleProduct: vi.fn().mockResolvedValue({
+    id: 'product-1',
+    user_id: 'user-1',
+  }),
+}))
+vi.mock('@/lib/rate-limit', () => ({
+  enforceUserRateLimit: vi.fn().mockReturnValue(null),
+}))
+vi.mock('@/lib/code-server', () => ({
+  createWithCodeRetry: vi.fn(async (_gen, fn) => fn('SP-1')),
+  generateNextSprintCode: vi.fn().mockResolvedValue('SP-1'),
+}))
+vi.mock('@/lib/active-sprint', () => ({
+  setActiveSprintInSettings: vi.fn().mockResolvedValue(undefined),
+}))
+vi.mock('@/lib/prisma', () => {
+  const txClient = {
+    sprint: { create: vi.fn() },
+    story: { updateMany: vi.fn() },
+    task: { updateMany: vi.fn() },
+  }
+  return {
+    prisma: {
+      sprint: {
+        create: vi.fn(),
+        findFirst: vi.fn(),
+        update: vi.fn(),
+      },
+      story: {
+        findMany: vi.fn(),
+        updateMany: vi.fn(),
+      },
+      task: {
+        findMany: vi.fn(),
+        updateMany: vi.fn(),
+      },
+      pbi: { findMany: vi.fn() },
+      user: {
+        findUnique: vi.fn(),
+        update: vi.fn(),
+      },
+      $transaction: vi.fn(async (fn: (tx: typeof txClient) => unknown) => fn(txClient)),
+      __txClient: txClient,
+    },
+  }
+})
+
+import { prisma } from '@/lib/prisma'
+import {
+  createSprintWithSelectionAction,
+  type CreateSprintWithSelectionInput,
+} from '@/actions/sprints'
+
+type Mocked = {
+  sprint: {
+    create: ReturnType<typeof vi.fn>
+    findFirst: ReturnType<typeof vi.fn>
+    update: ReturnType<typeof vi.fn>
+  }
+  story: {
+    findMany: ReturnType<typeof vi.fn>
+    updateMany: ReturnType<typeof vi.fn>
+  }
+  task: {
+    findMany: ReturnType<typeof vi.fn>
+    updateMany: ReturnType<typeof vi.fn>
+  }
+  $transaction: ReturnType<typeof vi.fn>
+  __txClient: {
+    sprint: { create: ReturnType<typeof vi.fn> }
+    story: { updateMany: ReturnType<typeof vi.fn> }
+    task: { updateMany: ReturnType<typeof vi.fn> }
+  }
+}
+const mockPrisma = prisma as unknown as Mocked
+
+function baseInput(
+  overrides: Partial<CreateSprintWithSelectionInput> = {},
+): CreateSprintWithSelectionInput {
+  return {
+    productId: 'product-1',
+    metadata: { goal: 'Sprint 1' },
+    pbiIntent: {},
+    storyOverrides: {},
+    ...overrides,
+  }
+}
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  mockPrisma.sprint.create.mockReset()
+  mockPrisma.story.findMany.mockReset()
+  mockPrisma.story.updateMany.mockReset()
+  mockPrisma.task.findMany.mockReset()
+  mockPrisma.task.updateMany.mockReset()
+  mockPrisma.$transaction.mockImplementation(
+    async (fn: (tx: typeof mockPrisma.__txClient) => unknown) =>
+      fn(mockPrisma.__txClient),
+  )
+  mockPrisma.__txClient.sprint.create
+    .mockReset()
+    .mockResolvedValue({ id: 'sprint-1', code: 'SP-1' })
+  mockPrisma.__txClient.story.updateMany
+    .mockReset()
+    .mockResolvedValue({ count: 0 })
+  mockPrisma.__txClient.task.updateMany
+    .mockReset()
+    .mockResolvedValue({ count: 0 })
+})
+
+describe('createSprintWithSelectionAction', () => {
+  it('resolves intent=all naar alle child-stories en weert overrides.remove', async () => {
+    // Stap 1: stories voor PBI-A (intent=all). Plus eligibility-fetch.
+    mockPrisma.story.findMany
+      // resolve step (only for pbis with intent='all')
+      .mockResolvedValueOnce([
+        { id: 's1', pbi_id: 'pbiA' },
+        { id: 's2', pbi_id: 'pbiA' },
+        { id: 's3', pbi_id: 'pbiA' },
+      ])
+      // partitionByEligibility — alle eligible
+      .mockResolvedValueOnce([
+        { id: 's1', sprint_id: null, status: 'OPEN', sprint: null },
+        { id: 's3', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      // affectedStories
+      .mockResolvedValueOnce([
+        { pbi_id: 'pbiA' },
+        { pbi_id: 'pbiA' },
+      ])
+    mockPrisma.task.findMany.mockResolvedValueOnce([{ id: 't1' }])
+
+    const result = await createSprintWithSelectionAction(
+      baseInput({
+        pbiIntent: { pbiA: 'all' },
+        storyOverrides: { pbiA: { add: [], remove: ['s2'] } },
+      }),
+    )
+
+    expect('success' in result).toBe(true)
+    if ('success' in result) {
+      expect(result.affectedStoryIds).toEqual(['s1', 's3'])
+      expect(result.conflicts.notEligible).toEqual([])
+    }
+  })
+
+  it('voegt storyOverrides.add toe over PBI heen (zelfs intent=none)', async () => {
+    // Geen PBI met intent=all → stap 1 wordt niet uitgevoerd.
+    mockPrisma.story.findMany
+      // partition
+      .mockResolvedValueOnce([
+        { id: 's10', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      // affectedStories
+      .mockResolvedValueOnce([{ pbi_id: 'pbiB' }])
+    mockPrisma.task.findMany.mockResolvedValueOnce([])
+
+    const result = await createSprintWithSelectionAction(
+      baseInput({
+        pbiIntent: { pbiB: 'none' },
+        storyOverrides: { pbiB: { add: ['s10'], remove: [] } },
+      }),
+    )
+
+    expect('success' in result).toBe(true)
+    if ('success' in result) {
+      expect(result.affectedStoryIds).toEqual(['s10'])
+    }
+  })
+
+  it('eligibility-filter classificeert DONE en cross-sprint stories', async () => {
+    mockPrisma.story.findMany
+      // resolve
+      .mockResolvedValueOnce([
+        { id: 's1', pbi_id: 'pbiA' },
+        { id: 's2', pbi_id: 'pbiA' },
+        { id: 's3', pbi_id: 'pbiA' },
+      ])
+      // partition: s1=DONE, s2=eligible, s3=in andere OPEN sprint
+      .mockResolvedValueOnce([
+        { id: 's1', sprint_id: null, status: 'DONE', sprint: null },
+        { id: 's2', sprint_id: null, status: 'OPEN', sprint: null },
+        {
+          id: 's3',
+          sprint_id: 'sprint-other',
+          status: 'IN_SPRINT',
+          sprint: { id: 'sprint-other', code: 'SP-O', status: 'OPEN' },
+        },
+      ])
+      // affectedStories
+      .mockResolvedValueOnce([{ pbi_id: 'pbiA' }])
+    mockPrisma.task.findMany.mockResolvedValueOnce([])
+
+    const result = await createSprintWithSelectionAction(
+      baseInput({ pbiIntent: { pbiA: 'all' } }),
+    )
+
+    expect('success' in result).toBe(true)
+    if ('success' in result) {
+      expect(result.affectedStoryIds).toEqual(['s2'])
+      expect(result.conflicts.notEligible.map((n) => n.storyId).sort()).toEqual(
+        ['s1', 's3'],
+      )
+      expect(result.conflicts.crossSprint.map((c) => c.storyId)).toEqual(['s3'])
+    }
+  })
+
+  it('zet story.status=IN_SPRINT en task.sprint_id mee in dezelfde transactie', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([{ id: 's1', pbi_id: 'pbiA' }])
+      .mockResolvedValueOnce([
+        { id: 's1', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      .mockResolvedValueOnce([{ pbi_id: 'pbiA' }])
+    mockPrisma.task.findMany.mockResolvedValueOnce([{ id: 't1' }])
+
+    await createSprintWithSelectionAction(
+      baseInput({ pbiIntent: { pbiA: 'all' } }),
+    )
+
+    expect(mockPrisma.$transaction).toHaveBeenCalledTimes(1)
+    expect(mockPrisma.__txClient.story.updateMany).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({
+          sprint_id: 'sprint-1',
+          status: 'IN_SPRINT',
+        }),
+      }),
+    )
+    expect(mockPrisma.__txClient.task.updateMany).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: { sprint_id: 'sprint-1' },
+      }),
+    )
+  })
+
+  it('returnt affectedStoryIds + affectedPbiIds + affectedTaskIds', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([
+        { id: 's1', pbi_id: 'pbiA' },
+        { id: 's2', pbi_id: 'pbiB' },
+      ])
+      .mockResolvedValueOnce([
+        { id: 's1', sprint_id: null, status: 'OPEN', sprint: null },
+        { id: 's2', sprint_id: null, status: 'OPEN', sprint: null },
+      ])
+      .mockResolvedValueOnce([{ pbi_id: 'pbiA' }, { pbi_id: 'pbiB' }])
+    mockPrisma.task.findMany.mockResolvedValueOnce([
+      { id: 't1' },
+      { id: 't2' },
+    ])
+
+    const result = await createSprintWithSelectionAction(
+      baseInput({ pbiIntent: { pbiA: 'all', pbiB: 'all' } }),
+    )
+
+    expect('success' in result).toBe(true)
+    if ('success' in result) {
+      expect(result.affectedStoryIds.sort()).toEqual(['s1', 's2'])
+      expect(result.affectedPbiIds.sort()).toEqual(['pbiA', 'pbiB'])
+      expect(result.affectedTaskIds.sort()).toEqual(['t1', 't2'])
+    }
+  })
+
+  it('returnt error wanneer geen eligible stories overblijven', async () => {
+    mockPrisma.story.findMany
+      .mockResolvedValueOnce([{ id: 's1', pbi_id: 'pbiA' }])
+      // s1 is DONE → notEligible
+      .mockResolvedValueOnce([
+        { id: 's1', sprint_id: null, status: 'DONE', sprint: null },
+      ])
+
+    const result = await createSprintWithSelectionAction(
+      baseInput({ pbiIntent: { pbiA: 'all' } }),
+    )
+
+    expect('error' in result).toBe(true)
+    if ('error' in result) {
+      expect(result.code).toBe(422)
+    }
+  })
+})

__tests__/actions/sprint-draft.test.ts

@@ -0,0 +1,167 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('next/cache', () => ({ revalidatePath: vi.fn() }))
+vi.mock('next/headers', () => ({
+  cookies: vi.fn().mockResolvedValue({
+    set: vi.fn(),
+    get: vi.fn(),
+    delete: vi.fn(),
+  }),
+}))
+vi.mock('iron-session', () => ({
+  getIronSession: vi.fn().mockResolvedValue({ userId: 'user-1', isDemo: false }),
+}))
+vi.mock('@/lib/session', () => ({
+  sessionOptions: { cookieName: 'test', password: 'test' },
+}))
+vi.mock('@/lib/product-access', () => ({
+  productAccessFilter: vi.fn().mockReturnValue({}),
+}))
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    product: { findFirst: vi.fn() },
+    user: {
+      findUnique: vi.fn(),
+      update: vi.fn().mockResolvedValue({}),
+    },
+    $executeRaw: vi.fn().mockResolvedValue(1),
+  },
+}))
+
+import { prisma } from '@/lib/prisma'
+import {
+  clearPendingSprintDraftAction,
+  setPendingSprintDraftAction,
+} from '@/actions/sprint-draft'
+import type { PendingSprintDraft, UserSettings } from '@/lib/user-settings'
+
+const mockPrisma = prisma as unknown as {
+  product: { findFirst: ReturnType<typeof vi.fn> }
+  user: {
+    findUnique: ReturnType<typeof vi.fn>
+    update: ReturnType<typeof vi.fn>
+  }
+}
+
+const validDraft: PendingSprintDraft = {
+  goal: 'Sprint 1',
+  pbiIntent: { pbiA: 'all' },
+  storyOverrides: { pbiA: { add: [], remove: ['story-1'] } },
+}
+
+describe('setPendingSprintDraftAction', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockPrisma.product.findFirst.mockReset()
+    mockPrisma.user.findUnique.mockReset()
+    mockPrisma.user.update.mockReset().mockResolvedValue({})
+  })
+
+  it('persists draft for accessible product', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce({ id: 'p1' })
+    mockPrisma.user.findUnique.mockResolvedValueOnce({ settings: {} })
+
+    const result = await setPendingSprintDraftAction('p1', validDraft)
+
+    expect(result).toEqual({ success: true })
+    const updateArg = mockPrisma.user.update.mock.calls[0][0] as {
+      data: { settings: UserSettings }
+    }
+    expect(updateArg.data.settings.workflow?.pendingSprintDraft?.p1).toMatchObject({
+      goal: 'Sprint 1',
+      pbiIntent: { pbiA: 'all' },
+    })
+  })
+
+  it('preserves drafts for other products', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce({ id: 'p1' })
+    mockPrisma.user.findUnique.mockResolvedValueOnce({
+      settings: {
+        workflow: {
+          pendingSprintDraft: {
+            p2: { goal: 'P2 draft', pbiIntent: {}, storyOverrides: {} },
+          },
+        },
+      },
+    })
+
+    await setPendingSprintDraftAction('p1', validDraft)
+
+    const updateArg = mockPrisma.user.update.mock.calls[0][0] as {
+      data: { settings: UserSettings }
+    }
+    const drafts = updateArg.data.settings.workflow?.pendingSprintDraft
+    expect(Object.keys(drafts ?? {})).toEqual(expect.arrayContaining(['p1', 'p2']))
+  })
+
+  it('rejects invalid draft (empty goal)', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce({ id: 'p1' })
+
+    const result = await setPendingSprintDraftAction('p1', {
+      ...validDraft,
+      goal: '',
+    } as PendingSprintDraft)
+
+    expect(result).toHaveProperty('error')
+    expect(mockPrisma.user.update).not.toHaveBeenCalled()
+  })
+
+  it('rejects when product not accessible', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce(null)
+
+    const result = await setPendingSprintDraftAction('p1', validDraft)
+
+    expect(result).toEqual({ error: 'Product niet gevonden of niet toegankelijk' })
+    expect(mockPrisma.user.update).not.toHaveBeenCalled()
+  })
+})
+
+describe('clearPendingSprintDraftAction', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockPrisma.product.findFirst.mockReset()
+    mockPrisma.user.findUnique.mockReset()
+    mockPrisma.user.update.mockReset().mockResolvedValue({})
+  })
+
+  it('removes draft key for product', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce({ id: 'p1' })
+    mockPrisma.user.findUnique.mockResolvedValueOnce({
+      settings: {
+        workflow: {
+          pendingSprintDraft: {
+            p1: { goal: 'gone', pbiIntent: {}, storyOverrides: {} },
+            p2: { goal: 'keep', pbiIntent: {}, storyOverrides: {} },
+          },
+        },
+      },
+    })
+
+    await clearPendingSprintDraftAction('p1')
+
+    const updateArg = mockPrisma.user.update.mock.calls[0][0] as {
+      data: { settings: UserSettings }
+    }
+    expect(updateArg.data.settings.workflow?.pendingSprintDraft).toEqual({
+      p2: { goal: 'keep', pbiIntent: {}, storyOverrides: {} },
+    })
+  })
+
+  it('is a no-op when there is no draft for the product', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce({ id: 'p1' })
+    mockPrisma.user.findUnique.mockResolvedValueOnce({ settings: {} })
+
+    const result = await clearPendingSprintDraftAction('p1')
+
+    expect(result).toEqual({ success: true })
+    expect(mockPrisma.user.update).not.toHaveBeenCalled()
+  })
+
+  it('rejects when product not accessible', async () => {
+    mockPrisma.product.findFirst.mockResolvedValueOnce(null)
+
+    const result = await clearPendingSprintDraftAction('p1')
+
+    expect(result).toEqual({ error: 'Product niet gevonden of niet toegankelijk' })
+  })
+})

__tests__/actions/update-sprint.test.ts

@@ -0,0 +1,148 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('next/cache', () => ({ revalidatePath: vi.fn() }))
+vi.mock('next/headers', () => ({
+  cookies: vi.fn().mockResolvedValue({
+    set: vi.fn(),
+    get: vi.fn(),
+    delete: vi.fn(),
+  }),
+}))
+vi.mock('iron-session', () => ({
+  getIronSession: vi.fn().mockResolvedValue({ userId: 'user-1', isDemo: false }),
+}))
+vi.mock('@/lib/session', () => ({
+  sessionOptions: { cookieName: 'test', password: 'test' },
+}))
+vi.mock('@/lib/product-access', () => ({
+  productAccessFilter: vi.fn().mockReturnValue({}),
+  getAccessibleProduct: vi.fn().mockResolvedValue({ id: 'product-1' }),
+}))
+vi.mock('@/lib/rate-limit', () => ({
+  enforceUserRateLimit: vi.fn().mockReturnValue(null),
+}))
+vi.mock('@/lib/code-server', () => ({
+  createWithCodeRetry: vi.fn(),
+  generateNextSprintCode: vi.fn(),
+}))
+vi.mock('@/lib/active-sprint', () => ({
+  setActiveSprintInSettings: vi.fn().mockResolvedValue(undefined),
+}))
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    sprint: {
+      findFirst: vi.fn(),
+      update: vi.fn(),
+    },
+    story: {
+      findMany: vi.fn(),
+      updateMany: vi.fn(),
+    },
+    task: {
+      findMany: vi.fn(),
+      updateMany: vi.fn(),
+    },
+    $transaction: vi.fn(),
+  },
+}))
+
+import { prisma } from '@/lib/prisma'
+import { updateSprintAction } from '@/actions/sprints'
+
+type Mocked = {
+  sprint: {
+    findFirst: ReturnType<typeof vi.fn>
+    update: ReturnType<typeof vi.fn>
+  }
+}
+const mockPrisma = prisma as unknown as Mocked
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  mockPrisma.sprint.findFirst.mockReset().mockResolvedValue({
+    id: 'sprint-1',
+    product_id: 'product-1',
+  })
+  mockPrisma.sprint.update.mockReset().mockResolvedValue({})
+})
+
+describe('updateSprintAction', () => {
+  it('updates sprint_goal alone', async () => {
+    const result = await updateSprintAction({
+      sprintId: 'sprint-1',
+      fields: { goal: 'Nieuw doel' },
+    })
+
+    expect('success' in result).toBe(true)
+    expect(mockPrisma.sprint.update).toHaveBeenCalledWith({
+      where: { id: 'sprint-1' },
+      data: { sprint_goal: 'Nieuw doel' },
+    })
+  })
+
+  it('updates dates only', async () => {
+    await updateSprintAction({
+      sprintId: 'sprint-1',
+      fields: { startAt: '2026-06-01', endAt: '2026-06-14' },
+    })
+
+    expect(mockPrisma.sprint.update).toHaveBeenCalledWith({
+      where: { id: 'sprint-1' },
+      data: {
+        start_date: new Date('2026-06-01'),
+        end_date: new Date('2026-06-14'),
+      },
+    })
+  })
+
+  it('accepts null to clear a date', async () => {
+    await updateSprintAction({
+      sprintId: 'sprint-1',
+      fields: { startAt: null },
+    })
+
+    expect(mockPrisma.sprint.update).toHaveBeenCalledWith({
+      where: { id: 'sprint-1' },
+      data: { start_date: null },
+    })
+  })
+
+  it('rejects when sprint not accessible', async () => {
+    mockPrisma.sprint.findFirst.mockResolvedValue(null)
+
+    const result = await updateSprintAction({
+      sprintId: 'sprint-1',
+      fields: { goal: 'x' },
+    })
+
+    expect('error' in result).toBe(true)
+    if ('error' in result) {
+      expect(result.code).toBe(403)
+    }
+    expect(mockPrisma.sprint.update).not.toHaveBeenCalled()
+  })
+
+  it('rejects empty goal', async () => {
+    const result = await updateSprintAction({
+      sprintId: 'sprint-1',
+      fields: { goal: '' },
+    })
+
+    expect('error' in result).toBe(true)
+    expect(mockPrisma.sprint.update).not.toHaveBeenCalled()
+  })
+
+  it('rejects when no fields are supplied', async () => {
+    const result = await updateSprintAction({
+      sprintId: 'sprint-1',
+      fields: {},
+    })
+
+    // Schema-refine should reject; OR action treats empty data as no-op success.
+    // Current implementation: refine forces minstens één veld → 422 error.
+    expect('error' in result).toBe(true)
+    if ('error' in result) {
+      expect(result.code).toBe(422)
+    }
+  })
+})

__tests__/api/cross-sprint-blocks.test.ts

@@ -0,0 +1,120 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    product: { findFirst: vi.fn() },
+    story: { findMany: vi.fn() },
+  },
+}))
+
+vi.mock('@/lib/api-auth', () => ({
+  authenticateApiRequest: vi.fn(),
+}))
+
+vi.mock('@/lib/product-access', () => ({
+  productAccessFilter: vi.fn().mockReturnValue({}),
+}))
+
+import { prisma } from '@/lib/prisma'
+import { authenticateApiRequest } from '@/lib/api-auth'
+import { GET } from '@/app/api/products/[id]/cross-sprint-blocks/route'
+
+const mockPrisma = prisma as unknown as {
+  product: { findFirst: ReturnType<typeof vi.fn> }
+  story: { findMany: ReturnType<typeof vi.fn> }
+}
+const mockAuth = authenticateApiRequest as unknown as ReturnType<typeof vi.fn>
+
+function makeRequest(url: string) {
+  return new Request(url)
+}
+
+describe('GET /api/products/[id]/cross-sprint-blocks', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockPrisma.product.findFirst.mockReset()
+    mockPrisma.story.findMany.mockReset()
+    mockAuth.mockReset().mockResolvedValue({ userId: 'user-1' })
+  })
+
+  it('returns blocking sprint info per story for happy path', async () => {
+    mockPrisma.product.findFirst.mockResolvedValue({ id: 'p1' })
+    mockPrisma.story.findMany.mockResolvedValue([
+      {
+        id: 'story-1',
+        sprint: { id: 'sprint-x', code: 'SP-X' },
+      },
+      {
+        id: 'story-2',
+        sprint: { id: 'sprint-y', code: 'SP-Y' },
+      },
+    ])
+
+    const req = makeRequest(
+      'http://localhost/api/products/p1/cross-sprint-blocks?excludeSprintId=sp-1&pbiIds=pbiA',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+
+    expect(res.status).toBe(200)
+    const body = await res.json()
+    expect(body).toEqual({
+      'story-1': { sprintId: 'sprint-x', sprintName: 'SP-X' },
+      'story-2': { sprintId: 'sprint-y', sprintName: 'SP-Y' },
+    })
+  })
+
+  it('rejects when pbiIds is missing', async () => {
+    const req = makeRequest(
+      'http://localhost/api/products/p1/cross-sprint-blocks?excludeSprintId=sp-1',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(400)
+  })
+
+  it('rejects when pbiIds is empty', async () => {
+    const req = makeRequest(
+      'http://localhost/api/products/p1/cross-sprint-blocks?pbiIds=',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(400)
+  })
+
+  it('returns 404 when product is not accessible', async () => {
+    mockPrisma.product.findFirst.mockResolvedValue(null)
+    const req = makeRequest(
+      'http://localhost/api/products/p1/cross-sprint-blocks?pbiIds=pbiA',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(404)
+  })
+
+  it('returns auth error when authenticate fails', async () => {
+    mockAuth.mockResolvedValue({ error: 'Niet ingelogd', status: 401 })
+    const req = makeRequest(
+      'http://localhost/api/products/p1/cross-sprint-blocks?pbiIds=pbiA',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(401)
+  })
+
+  it('passes NOT excludeSprintId to prisma when provided', async () => {
+    mockPrisma.product.findFirst.mockResolvedValue({ id: 'p1' })
+    mockPrisma.story.findMany.mockResolvedValue([])
+
+    const req = makeRequest(
+      'http://localhost/api/products/p1/cross-sprint-blocks?excludeSprintId=sp-active&pbiIds=pbiA',
+    )
+    await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+
+    const callArg = mockPrisma.story.findMany.mock.calls[0][0] as {
+      where: Record<string, unknown>
+    }
+    expect(callArg.where).toMatchObject({
+      pbi_id: { in: ['pbiA'] },
+      product_id: 'p1',
+      sprint_id: { not: null },
+      NOT: { sprint_id: 'sp-active' },
+      sprint: { status: 'OPEN' },
+    })
+  })
+})

__tests__/api/sprint-membership-summary.test.ts

@@ -0,0 +1,121 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    product: { findFirst: vi.fn() },
+    story: { groupBy: vi.fn() },
+  },
+}))
+
+vi.mock('@/lib/api-auth', () => ({
+  authenticateApiRequest: vi.fn(),
+}))
+
+vi.mock('@/lib/product-access', () => ({
+  productAccessFilter: vi.fn().mockReturnValue({}),
+}))
+
+import { prisma } from '@/lib/prisma'
+import { authenticateApiRequest } from '@/lib/api-auth'
+import { GET } from '@/app/api/products/[id]/sprint-membership-summary/route'
+
+const mockPrisma = prisma as unknown as {
+  product: { findFirst: ReturnType<typeof vi.fn> }
+  story: { groupBy: ReturnType<typeof vi.fn> }
+}
+const mockAuth = authenticateApiRequest as unknown as ReturnType<typeof vi.fn>
+
+function makeRequest(url: string) {
+  return new Request(url)
+}
+
+describe('GET /api/products/[id]/sprint-membership-summary', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockPrisma.product.findFirst.mockReset()
+    mockPrisma.story.groupBy.mockReset()
+    mockAuth.mockReset().mockResolvedValue({ userId: 'user-1' })
+  })
+
+  it('returns counts per PBI for happy path', async () => {
+    mockPrisma.product.findFirst.mockResolvedValue({ id: 'p1' })
+    mockPrisma.story.groupBy
+      .mockResolvedValueOnce([
+        { pbi_id: 'pbiA', _count: { _all: 5 } },
+        { pbi_id: 'pbiB', _count: { _all: 3 } },
+      ])
+      .mockResolvedValueOnce([{ pbi_id: 'pbiA', _count: { _all: 2 } }])
+
+    const req = makeRequest(
+      'http://localhost/api/products/p1/sprint-membership-summary?sprintId=sp-1&pbiIds=pbiA,pbiB',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+
+    expect(res.status).toBe(200)
+    const body = await res.json()
+    expect(body).toEqual({
+      pbiA: { total: 5, inSprint: 2 },
+      pbiB: { total: 3, inSprint: 0 },
+    })
+  })
+
+  it('rejects when pbiIds is missing', async () => {
+    const req = makeRequest(
+      'http://localhost/api/products/p1/sprint-membership-summary?sprintId=sp-1',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(400)
+  })
+
+  it('rejects when pbiIds is empty', async () => {
+    const req = makeRequest(
+      'http://localhost/api/products/p1/sprint-membership-summary?sprintId=sp-1&pbiIds=',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(400)
+  })
+
+  it('rejects when sprintId is missing', async () => {
+    const req = makeRequest(
+      'http://localhost/api/products/p1/sprint-membership-summary?pbiIds=pbiA',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(400)
+  })
+
+  it('returns 404 when product is not accessible', async () => {
+    mockPrisma.product.findFirst.mockResolvedValue(null)
+    const req = makeRequest(
+      'http://localhost/api/products/p1/sprint-membership-summary?sprintId=sp-1&pbiIds=pbiA',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(404)
+  })
+
+  it('returns auth error when authenticate fails', async () => {
+    mockAuth.mockResolvedValue({ error: 'Niet ingelogd', status: 401 })
+    const req = makeRequest(
+      'http://localhost/api/products/p1/sprint-membership-summary?sprintId=sp-1&pbiIds=pbiA',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+    expect(res.status).toBe(401)
+  })
+
+  it('returns zero counts for PBIs without stories', async () => {
+    mockPrisma.product.findFirst.mockResolvedValue({ id: 'p1' })
+    mockPrisma.story.groupBy
+      .mockResolvedValueOnce([])
+      .mockResolvedValueOnce([])
+
+    const req = makeRequest(
+      'http://localhost/api/products/p1/sprint-membership-summary?sprintId=sp-1&pbiIds=pbiA,pbiB',
+    )
+    const res = await GET(req, { params: Promise.resolve({ id: 'p1' }) })
+
+    const body = await res.json()
+    expect(body).toEqual({
+      pbiA: { total: 0, inSprint: 0 },
+      pbiB: { total: 0, inSprint: 0 },
+    })
+  })
+})

__tests__/lib/active-sprint.test.ts

@@ -0,0 +1,190 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    sprint: { findFirst: vi.fn() },
+    user: {
+      findUnique: vi.fn(),
+      update: vi.fn().mockResolvedValue({}),
+    },
+    $executeRaw: vi.fn().mockResolvedValue(1),
+  },
+}))
+
+import { prisma } from '@/lib/prisma'
+import type { UserSettings } from '@/lib/user-settings'
+import {
+  clearActiveSprintInSettings,
+  readStoredActiveSprintState,
+  resolveActiveSprint,
+} from '@/lib/active-sprint'
+
+const mockPrisma = prisma as unknown as {
+  sprint: { findFirst: ReturnType<typeof vi.fn> }
+  user: {
+    findUnique: ReturnType<typeof vi.fn>
+    update: ReturnType<typeof vi.fn>
+  }
+  $executeRaw: ReturnType<typeof vi.fn>
+}
+
+function withSettings(settings: UserSettings) {
+  mockPrisma.user.findUnique.mockResolvedValueOnce({ settings })
+}
+
+describe('readStoredActiveSprintState', () => {
+  it('returns unset when activeSprints map is absent', () => {
+    expect(readStoredActiveSprintState({}, 'p1')).toEqual({ kind: 'unset' })
+  })
+
+  it('returns unset when productId key is absent', () => {
+    const settings: UserSettings = {
+      layout: { activeSprints: { p2: 'sprint-2' } },
+    }
+    expect(readStoredActiveSprintState(settings, 'p1')).toEqual({
+      kind: 'unset',
+    })
+  })
+
+  it('returns cleared when key is present with null value', () => {
+    const settings: UserSettings = {
+      layout: { activeSprints: { p1: null } },
+    }
+    expect(readStoredActiveSprintState(settings, 'p1')).toEqual({
+      kind: 'cleared',
+    })
+  })
+
+  it('returns set when key is present with string value', () => {
+    const settings: UserSettings = {
+      layout: { activeSprints: { p1: 'sprint-1' } },
+    }
+    expect(readStoredActiveSprintState(settings, 'p1')).toEqual({
+      kind: 'set',
+      sprintId: 'sprint-1',
+    })
+  })
+})
+
+describe('resolveActiveSprint', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('returns null without fallback when key is explicitly null (cleared)', async () => {
+    withSettings({ layout: { activeSprints: { p1: null } } })
+
+    const result = await resolveActiveSprint('p1', 'user-1')
+
+    expect(result).toBeNull()
+    expect(mockPrisma.sprint.findFirst).not.toHaveBeenCalled()
+  })
+
+  it('returns the stored sprint when key is set and sprint exists', async () => {
+    withSettings({ layout: { activeSprints: { p1: 'sprint-1' } } })
+    mockPrisma.sprint.findFirst.mockResolvedValueOnce({
+      id: 'sprint-1',
+      code: 'SP-1',
+      status: 'OPEN',
+    })
+
+    const result = await resolveActiveSprint('p1', 'user-1')
+
+    expect(result).toEqual({ id: 'sprint-1', code: 'SP-1', status: 'OPEN' })
+    expect(mockPrisma.sprint.findFirst).toHaveBeenCalledTimes(1)
+  })
+
+  it('falls back when stored sprint is not found in DB', async () => {
+    withSettings({ layout: { activeSprints: { p1: 'stale-id' } } })
+    mockPrisma.sprint.findFirst
+      .mockResolvedValueOnce(null) // stored lookup misses
+      .mockResolvedValueOnce({ id: 'sprint-open', code: 'SP-O', status: 'OPEN' })
+
+    const result = await resolveActiveSprint('p1', 'user-1')
+
+    expect(result).toEqual({
+      id: 'sprint-open',
+      code: 'SP-O',
+      status: 'OPEN',
+    })
+  })
+
+  it('falls back to first OPEN sprint when key is absent', async () => {
+    withSettings({})
+    mockPrisma.sprint.findFirst.mockResolvedValueOnce({
+      id: 'sprint-open',
+      code: 'SP-O',
+      status: 'OPEN',
+    })
+
+    const result = await resolveActiveSprint('p1', 'user-1')
+
+    expect(result).toEqual({
+      id: 'sprint-open',
+      code: 'SP-O',
+      status: 'OPEN',
+    })
+  })
+
+  it('falls back to recent CLOSED sprint when no OPEN exists', async () => {
+    withSettings({})
+    mockPrisma.sprint.findFirst
+      .mockResolvedValueOnce(null) // no OPEN
+      .mockResolvedValueOnce({
+        id: 'sprint-closed',
+        code: 'SP-C',
+        status: 'CLOSED',
+      })
+
+    const result = await resolveActiveSprint('p1', 'user-1')
+
+    expect(result).toEqual({
+      id: 'sprint-closed',
+      code: 'SP-C',
+      status: 'CLOSED',
+    })
+  })
+
+  it('returns null when key absent and no sprints exist', async () => {
+    withSettings({})
+    mockPrisma.sprint.findFirst.mockResolvedValue(null)
+
+    const result = await resolveActiveSprint('p1', 'user-1')
+
+    expect(result).toBeNull()
+  })
+})
+
+describe('clearActiveSprintInSettings', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('writes null instead of deleting the key', async () => {
+    withSettings({
+      layout: { activeSprints: { p1: 'sprint-1', p2: 'sprint-2' } },
+    })
+
+    await clearActiveSprintInSettings('user-1', 'p1')
+
+    expect(mockPrisma.user.update).toHaveBeenCalledTimes(1)
+    const updateArg = mockPrisma.user.update.mock.calls[0][0] as {
+      data: { settings: UserSettings }
+    }
+    expect(updateArg.data.settings.layout?.activeSprints).toEqual({
+      p1: null,
+      p2: 'sprint-2',
+    })
+  })
+
+  it('adds the key with null when previously unset', async () => {
+    withSettings({})
+
+    await clearActiveSprintInSettings('user-1', 'p1')
+
+    const updateArg = mockPrisma.user.update.mock.calls[0][0] as {
+      data: { settings: UserSettings }
+    }
+    expect(updateArg.data.settings.layout?.activeSprints).toEqual({ p1: null })
+  })
+})

__tests__/lib/sprint-conflicts.test.ts

@@ -0,0 +1,195 @@
+import { describe, it, expect, vi } from 'vitest'
+import type { StoryStatus } from '@prisma/client'
+
+import {
+  getBlockingSprintMap,
+  isEligibleForSprint,
+  partitionByEligibility,
+} from '@/lib/sprint-conflicts'
+
+function mockPrisma(stories: Array<Record<string, unknown>>) {
+  return {
+    story: {
+      findMany: vi.fn().mockResolvedValue(stories),
+    },
+  } as unknown as Parameters<typeof partitionByEligibility>[0]
+}
+
+describe('isEligibleForSprint', () => {
+  it('returns true for OPEN story without sprint', () => {
+    expect(
+      isEligibleForSprint({ sprint_id: null, status: 'OPEN' as StoryStatus }),
+    ).toBe(true)
+  })
+
+  it('returns true for IN_SPRINT story without sprint_id (edge: restoration)', () => {
+    expect(
+      isEligibleForSprint({
+        sprint_id: null,
+        status: 'IN_SPRINT' as StoryStatus,
+      }),
+    ).toBe(true)
+  })
+
+  it('returns false for DONE story without sprint', () => {
+    expect(
+      isEligibleForSprint({ sprint_id: null, status: 'DONE' as StoryStatus }),
+    ).toBe(false)
+  })
+
+  it('returns false when story is in any sprint (open status)', () => {
+    expect(
+      isEligibleForSprint({
+        sprint_id: 'abc',
+        status: 'OPEN' as StoryStatus,
+      }),
+    ).toBe(false)
+  })
+
+  it('returns false when story is in any sprint (done status)', () => {
+    expect(
+      isEligibleForSprint({
+        sprint_id: 'abc',
+        status: 'DONE' as StoryStatus,
+      }),
+    ).toBe(false)
+  })
+})
+
+describe('partitionByEligibility', () => {
+  it('returns empty partition for empty input', async () => {
+    const prisma = mockPrisma([])
+    const result = await partitionByEligibility(prisma, [])
+    expect(result).toEqual({ eligible: [], notEligible: [], crossSprint: [] })
+  })
+
+  it('classifies all eligible when stories are free + OPEN', async () => {
+    const prisma = mockPrisma([
+      { id: 's1', sprint_id: null, status: 'OPEN', sprint: null },
+      { id: 's2', sprint_id: null, status: 'IN_SPRINT', sprint: null },
+    ])
+    const result = await partitionByEligibility(prisma, ['s1', 's2'])
+    expect(result.eligible).toEqual(['s1', 's2'])
+    expect(result.notEligible).toEqual([])
+    expect(result.crossSprint).toEqual([])
+  })
+
+  it('marks DONE stories as notEligible with reason=DONE', async () => {
+    const prisma = mockPrisma([
+      { id: 's1', sprint_id: null, status: 'DONE', sprint: null },
+    ])
+    const result = await partitionByEligibility(prisma, ['s1'])
+    expect(result.eligible).toEqual([])
+    expect(result.notEligible).toEqual([{ storyId: 's1', reason: 'DONE' }])
+  })
+
+  it('marks stories in other OPEN sprint as crossSprint + notEligible', async () => {
+    const prisma = mockPrisma([
+      {
+        id: 's1',
+        sprint_id: 'sprint-other',
+        status: 'IN_SPRINT',
+        sprint: { id: 'sprint-other', code: 'SP-2', status: 'OPEN' },
+      },
+    ])
+    const result = await partitionByEligibility(prisma, ['s1'])
+    expect(result.crossSprint).toEqual([
+      { storyId: 's1', sprintId: 'sprint-other', sprintName: 'SP-2' },
+    ])
+    expect(result.notEligible).toEqual([
+      { storyId: 's1', reason: 'IN_OTHER_SPRINT' },
+    ])
+    expect(result.eligible).toEqual([])
+  })
+
+  it('classifies story in CLOSED sprint with status=OPEN as eligible (status reset already happened)', async () => {
+    const prisma = mockPrisma([
+      {
+        id: 's1',
+        sprint_id: null,
+        status: 'OPEN',
+        sprint: null,
+      },
+    ])
+    const result = await partitionByEligibility(prisma, ['s1'])
+    expect(result.eligible).toEqual(['s1'])
+  })
+
+  it('does NOT mark crossSprint for stories in CLOSED other sprint', async () => {
+    const prisma = mockPrisma([
+      {
+        id: 's1',
+        sprint_id: 'sprint-closed',
+        status: 'DONE',
+        sprint: { id: 'sprint-closed', code: 'SP-C', status: 'CLOSED' },
+      },
+    ])
+    const result = await partitionByEligibility(prisma, ['s1'])
+    expect(result.crossSprint).toEqual([])
+    expect(result.notEligible).toEqual([
+      { storyId: 's1', reason: 'IN_OTHER_SPRINT' },
+    ])
+  })
+
+  it('respects excludeSprintId — story in same sprint is eligible', async () => {
+    const prisma = mockPrisma([
+      {
+        id: 's1',
+        sprint_id: 'sprint-active',
+        status: 'IN_SPRINT',
+        sprint: { id: 'sprint-active', code: 'SP-A', status: 'OPEN' },
+      },
+    ])
+    const result = await partitionByEligibility(prisma, ['s1'], 'sprint-active')
+    expect(result.eligible).toEqual(['s1'])
+    expect(result.crossSprint).toEqual([])
+  })
+})
+
+describe('getBlockingSprintMap', () => {
+  it('returns empty map for empty input', async () => {
+    const prisma = mockPrisma([])
+    const result = await getBlockingSprintMap(prisma, 'p1', [])
+    expect(result.size).toBe(0)
+  })
+
+  it('returns blocking sprint info for stories in OPEN sprints', async () => {
+    const prisma = mockPrisma([
+      {
+        id: 's1',
+        sprint_id: 'sprint-x',
+        sprint: { id: 'sprint-x', code: 'SP-X', status: 'OPEN' },
+      },
+    ])
+    const result = await getBlockingSprintMap(prisma, 'p1', ['s1'])
+    expect(result.get('s1')).toEqual({
+      sprintId: 'sprint-x',
+      sprintName: 'SP-X',
+    })
+  })
+
+  it('excludes the active sprint from blocking', async () => {
+    const prisma = mockPrisma([
+      {
+        id: 's1',
+        sprint_id: 'sprint-active',
+        sprint: { id: 'sprint-active', code: 'SP-A', status: 'OPEN' },
+      },
+    ])
+    const result = await getBlockingSprintMap(
+      prisma,
+      'p1',
+      ['s1'],
+      'sprint-active',
+    )
+    expect(result.size).toBe(0)
+  })
+
+  it('does not include CLOSED sprints (filtered at DB query level)', async () => {
+    // The prisma mock receives WHERE sprint.status='OPEN' so CLOSED stories
+    // are already filtered out before reaching this function's mapping logic.
+    const prisma = mockPrisma([])
+    const result = await getBlockingSprintMap(prisma, 'p1', ['s1'])
+    expect(result.size).toBe(0)
+  })
+})

__tests__/lib/user-settings.test.ts

@@ -122,4 +122,65 @@ describe('UserSettingsSchema', () => {
       layout: { splitPanePositions: { x: [50, 50] }, activeSprints: { p: 's' } },
     }).success).toBe(true)
   })
+
+  it('accepts null values in activeSprints (explicit "no active sprint")', () => {
+    const result = UserSettingsSchema.safeParse({
+      layout: { activeSprints: { 'product-1': null, 'product-2': 'sprint-2' } },
+    })
+    expect(result.success).toBe(true)
+    if (result.success) {
+      expect(result.data.layout?.activeSprints).toEqual({
+        'product-1': null,
+        'product-2': 'sprint-2',
+      })
+    }
+  })
+
+  it('accepts pendingSprintDraft with per-PBI intent and overrides', () => {
+    const result = UserSettingsSchema.safeParse({
+      workflow: {
+        pendingSprintDraft: {
+          'product-1': {
+            goal: 'Sprint goal',
+            pbiIntent: { pbiA: 'all', pbiB: 'none' },
+            storyOverrides: {
+              pbiA: { add: [], remove: ['story-1'] },
+              pbiB: { add: ['story-2'], remove: [] },
+            },
+          },
+        },
+      },
+    })
+    expect(result.success).toBe(true)
+  })
+
+  it('fills empty defaults for pbiIntent and storyOverrides in draft', () => {
+    const result = UserSettingsSchema.safeParse({
+      workflow: { pendingSprintDraft: { 'product-1': { goal: 'g' } } },
+    })
+    expect(result.success).toBe(true)
+    if (result.success) {
+      const draft = result.data.workflow?.pendingSprintDraft?.['product-1']
+      expect(draft?.pbiIntent).toEqual({})
+      expect(draft?.storyOverrides).toEqual({})
+    }
+  })
+
+  it('rejects pendingSprintDraft with empty goal', () => {
+    const result = UserSettingsSchema.safeParse({
+      workflow: { pendingSprintDraft: { 'p': { goal: '' } } },
+    })
+    expect(result.success).toBe(false)
+  })
+
+  it('rejects unknown intent value', () => {
+    const result = UserSettingsSchema.safeParse({
+      workflow: {
+        pendingSprintDraft: {
+          p: { goal: 'x', pbiIntent: { a: 'partial' } },
+        },
+      },
+    })
+    expect(result.success).toBe(false)
+  })
 })

__tests__/stores/product-workspace/sprint-membership.test.ts

@@ -0,0 +1,341 @@
+// @vitest-environment jsdom
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+import { useProductWorkspaceStore } from '@/stores/product-workspace/store'
+import {
+  selectIsDirty,
+  selectPbiTriState,
+  selectPendingCount,
+  selectStoryEffectiveInSprint,
+  selectStoryIsBlocked,
+} from '@/stores/product-workspace/selectors'
+import type { BacklogStory } from '@/stores/product-workspace/types'
+
+function resetMembership() {
+  useProductWorkspaceStore.setState((s) => {
+    s.entities.storiesById = {}
+    s.relations.storyIdsByPbi = {}
+    s.sprintMembership = {
+      pbiSummary: {},
+      crossSprintBlocks: {},
+      pending: { adds: [], removes: [] },
+      loadedSummaryForSprintId: null,
+    }
+  })
+}
+
+function seedStory(id: string, pbiId: string, sprintId: string | null): BacklogStory {
+  return {
+    id,
+    code: id,
+    title: id,
+    description: null,
+    acceptance_criteria: null,
+    priority: 2,
+    sort_order: 1,
+    status: sprintId ? 'IN_SPRINT' : 'OPEN',
+    pbi_id: pbiId,
+    sprint_id: sprintId,
+    created_at: new Date('2026-01-01'),
+  }
+}
+
+beforeEach(() => {
+  resetMembership()
+})
+
+describe('toggleStorySprintMembership', () => {
+  it('adds storyId to pending.adds when currently not in sprint', () => {
+    useProductWorkspaceStore.getState().toggleStorySprintMembership('s1', false)
+    const pending = useProductWorkspaceStore.getState().sprintMembership.pending
+    expect(pending.adds).toEqual(['s1'])
+    expect(pending.removes).toEqual([])
+  })
+
+  it('adds storyId to pending.removes when currently in sprint', () => {
+    useProductWorkspaceStore.getState().toggleStorySprintMembership('s1', true)
+    const pending = useProductWorkspaceStore.getState().sprintMembership.pending
+    expect(pending.removes).toEqual(['s1'])
+    expect(pending.adds).toEqual([])
+  })
+
+  it('cancels out: toggle add → toggle remove same story (in-sprint) clears pending', () => {
+    const store = useProductWorkspaceStore.getState()
+    store.toggleStorySprintMembership('s1', false) // adds
+    // Story now appears to be "in sprint" via pending; calling with true should cancel
+    store.toggleStorySprintMembership('s1', false) // second click with same baseline
+    const pending = useProductWorkspaceStore.getState().sprintMembership.pending
+    expect(pending.adds).toEqual([])
+    expect(pending.removes).toEqual([])
+  })
+
+  it('removes from pending.removes when toggled back', () => {
+    const store = useProductWorkspaceStore.getState()
+    store.toggleStorySprintMembership('s1', true)
+    store.toggleStorySprintMembership('s1', true)
+    const pending = useProductWorkspaceStore.getState().sprintMembership.pending
+    expect(pending.removes).toEqual([])
+    expect(pending.adds).toEqual([])
+  })
+
+  it('resetSprintMembershipPending empties both arrays', () => {
+    const store = useProductWorkspaceStore.getState()
+    store.toggleStorySprintMembership('s1', false)
+    store.toggleStorySprintMembership('s2', true)
+    store.resetSprintMembershipPending()
+    const pending = useProductWorkspaceStore.getState().sprintMembership.pending
+    expect(pending.adds).toEqual([])
+    expect(pending.removes).toEqual([])
+  })
+})
+
+describe('selectPbiTriState', () => {
+  function seedSummary(pbiId: string, total: number, inSprint: number) {
+    useProductWorkspaceStore.setState((s) => {
+      s.sprintMembership.pbiSummary[pbiId] = {
+        totalStoryCount: total,
+        inActiveSprintStoryCount: inSprint,
+      }
+    })
+  }
+
+  it('returns empty for PBI without summary', () => {
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('empty')
+  })
+
+  it('returns empty when totalStoryCount == 0', () => {
+    seedSummary('pbi-1', 0, 0)
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('empty')
+  })
+
+  it('returns full when all stories in sprint (no pending)', () => {
+    seedSummary('pbi-1', 3, 3)
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('full')
+  })
+
+  it('returns partial when some stories in sprint', () => {
+    seedSummary('pbi-1', 3, 2)
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('partial')
+  })
+
+  it('returns empty when inSprint == 0', () => {
+    seedSummary('pbi-1', 3, 0)
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('empty')
+  })
+
+  it('applies pending adds when stories are loaded for the PBI', () => {
+    seedSummary('pbi-1', 3, 1)
+    useProductWorkspaceStore.setState((s) => {
+      s.relations.storyIdsByPbi['pbi-1'] = ['s1', 's2', 's3']
+      s.entities.storiesById['s1'] = seedStory('s1', 'pbi-1', 'sprint-1')
+      s.entities.storiesById['s2'] = seedStory('s2', 'pbi-1', null)
+      s.entities.storiesById['s3'] = seedStory('s3', 'pbi-1', null)
+      s.sprintMembership.pending.adds = ['s2', 's3']
+    })
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('full')
+  })
+
+  it('applies pending removes when stories are loaded for the PBI', () => {
+    seedSummary('pbi-1', 3, 3)
+    useProductWorkspaceStore.setState((s) => {
+      s.relations.storyIdsByPbi['pbi-1'] = ['s1', 's2', 's3']
+      s.sprintMembership.pending.removes = ['s2']
+    })
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('partial')
+  })
+
+  it('ignores pending entries for stories of other PBIs', () => {
+    seedSummary('pbi-1', 3, 3)
+    useProductWorkspaceStore.setState((s) => {
+      s.relations.storyIdsByPbi['pbi-1'] = ['s1', 's2', 's3']
+      s.sprintMembership.pending.removes = ['s99'] // not in pbi-1
+    })
+    expect(
+      selectPbiTriState(useProductWorkspaceStore.getState(), 'pbi-1'),
+    ).toBe('full')
+  })
+})
+
+describe('selectStoryEffectiveInSprint', () => {
+  it('returns true when story.sprint_id matches activeSprintId and no pending', () => {
+    useProductWorkspaceStore.setState((s) => {
+      s.entities.storiesById['s1'] = seedStory('s1', 'pbi-1', 'sprint-A')
+    })
+    expect(
+      selectStoryEffectiveInSprint(
+        useProductWorkspaceStore.getState(),
+        's1',
+        'sprint-A',
+      ),
+    ).toBe(true)
+  })
+
+  it('returns false when story.sprint_id is null', () => {
+    useProductWorkspaceStore.setState((s) => {
+      s.entities.storiesById['s1'] = seedStory('s1', 'pbi-1', null)
+    })
+    expect(
+      selectStoryEffectiveInSprint(
+        useProductWorkspaceStore.getState(),
+        's1',
+        'sprint-A',
+      ),
+    ).toBe(false)
+  })
+
+  it('returns true when story in pending.adds even if DB says no', () => {
+    useProductWorkspaceStore.setState((s) => {
+      s.entities.storiesById['s1'] = seedStory('s1', 'pbi-1', null)
+      s.sprintMembership.pending.adds = ['s1']
+    })
+    expect(
+      selectStoryEffectiveInSprint(
+        useProductWorkspaceStore.getState(),
+        's1',
+        'sprint-A',
+      ),
+    ).toBe(true)
+  })
+
+  it('returns false when story in pending.removes even if DB says yes', () => {
+    useProductWorkspaceStore.setState((s) => {
+      s.entities.storiesById['s1'] = seedStory('s1', 'pbi-1', 'sprint-A')
+      s.sprintMembership.pending.removes = ['s1']
+    })
+    expect(
+      selectStoryEffectiveInSprint(
+        useProductWorkspaceStore.getState(),
+        's1',
+        'sprint-A',
+      ),
+    ).toBe(false)
+  })
+
+  it('returns false when activeSprintId is null', () => {
+    useProductWorkspaceStore.setState((s) => {
+      s.entities.storiesById['s1'] = seedStory('s1', 'pbi-1', 'sprint-A')
+    })
+    expect(
+      selectStoryEffectiveInSprint(
+        useProductWorkspaceStore.getState(),
+        's1',
+        null,
+      ),
+    ).toBe(false)
+  })
+})
+
+describe('selectStoryIsBlocked', () => {
+  it('returns null when no block', () => {
+    expect(
+      selectStoryIsBlocked(useProductWorkspaceStore.getState(), 's1'),
+    ).toBeNull()
+  })
+
+  it('returns block info when story is in another sprint', () => {
+    useProductWorkspaceStore.setState((s) => {
+      s.sprintMembership.crossSprintBlocks['s1'] = {
+        sprintId: 'sprint-x',
+        sprintName: 'SP-X',
+      }
+    })
+    expect(
+      selectStoryIsBlocked(useProductWorkspaceStore.getState(), 's1'),
+    ).toEqual({ sprintId: 'sprint-x', sprintName: 'SP-X' })
+  })
+})
+
+describe('selectIsDirty + selectPendingCount', () => {
+  it('clean by default', () => {
+    expect(selectIsDirty(useProductWorkspaceStore.getState())).toBe(false)
+    expect(selectPendingCount(useProductWorkspaceStore.getState())).toBe(0)
+  })
+
+  it('counts adds + removes', () => {
+    useProductWorkspaceStore.setState((s) => {
+      s.sprintMembership.pending = {
+        adds: ['a1', 'a2'],
+        removes: ['r1'],
+      }
+    })
+    expect(selectIsDirty(useProductWorkspaceStore.getState())).toBe(true)
+    expect(selectPendingCount(useProductWorkspaceStore.getState())).toBe(3)
+  })
+})
+
+describe('fetch helpers', () => {
+  it('fetchSprintMembershipSummary populates store and gates by sprintId', async () => {
+    const originalFetch = globalThis.fetch
+    const responseBody = {
+      pbiA: { totalStoryCount: 5, inActiveSprintStoryCount: 2 },
+    }
+    globalThis.fetch = vi.fn().mockResolvedValue(
+      new Response(JSON.stringify(responseBody), { status: 200 }),
+    ) as unknown as typeof fetch
+    try {
+      await useProductWorkspaceStore
+        .getState()
+        .fetchSprintMembershipSummary('prod-1', 'sprint-A', ['pbiA'])
+
+      const slice = useProductWorkspaceStore.getState().sprintMembership
+      expect(slice.pbiSummary.pbiA).toEqual({
+        totalStoryCount: 5,
+        inActiveSprintStoryCount: 2,
+      })
+      expect(slice.loadedSummaryForSprintId).toBe('sprint-A')
+    } finally {
+      globalThis.fetch = originalFetch
+    }
+  })
+
+  it('fetchCrossSprintBlocks populates store', async () => {
+    const originalFetch = globalThis.fetch
+    const responseBody = {
+      's1': { sprintId: 'sprint-x', sprintName: 'SP-X' },
+    }
+    globalThis.fetch = vi.fn().mockResolvedValue(
+      new Response(JSON.stringify(responseBody), { status: 200 }),
+    ) as unknown as typeof fetch
+    try {
+      await useProductWorkspaceStore
+        .getState()
+        .fetchCrossSprintBlocks('prod-1', 'sprint-A', ['pbiA'])
+
+      const slice = useProductWorkspaceStore.getState().sprintMembership
+      expect(slice.crossSprintBlocks['s1']).toEqual({
+        sprintId: 'sprint-x',
+        sprintName: 'SP-X',
+      })
+    } finally {
+      globalThis.fetch = originalFetch
+    }
+  })
+
+  it('fetchSprintMembershipSummary is a no-op for empty pbiIds', async () => {
+    const fetchSpy = vi.fn()
+    const originalFetch = globalThis.fetch
+    globalThis.fetch = fetchSpy as unknown as typeof fetch
+    try {
+      await useProductWorkspaceStore
+        .getState()
+        .fetchSprintMembershipSummary('prod-1', 'sprint-A', [])
+      expect(fetchSpy).not.toHaveBeenCalled()
+    } finally {
+      globalThis.fetch = originalFetch
+    }
+  })
+})

__tests__/stores/product-workspace/store.test.ts

@@ -56,6 +56,12 @@ function resetStore() {
     s.sync.lastResyncAt = null
     s.sync.resyncReason = null
     s.pendingMutations = {}
+    s.sprintMembership = {
+      pbiSummary: {},
+      crossSprintBlocks: {},
+      pending: { adds: [], removes: [] },
+      loadedSummaryForSprintId: null,
+    }
     Object.assign(s, originalActions)
   })
 }

__tests__/stores/user-settings.test.ts

@@ -1,12 +1,21 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 
 const updateAction = vi.fn()
+const setDraftAction = vi.fn()
+const clearDraftAction = vi.fn()
 
 vi.mock('@/actions/user-settings', () => ({
   updateUserSettingsAction: (...args: unknown[]) => updateAction(...args),
 }))
 
+vi.mock('@/actions/sprint-draft', () => ({
+  setPendingSprintDraftAction: (...args: unknown[]) => setDraftAction(...args),
+  clearPendingSprintDraftAction: (...args: unknown[]) =>
+    clearDraftAction(...args),
+}))
+
 import { useUserSettingsStore } from '@/stores/user-settings/store'
+import type { PendingSprintDraft } from '@/lib/user-settings'
 
 function resetStore() {
   useUserSettingsStore.setState((s) => {
@@ -20,6 +29,8 @@ function resetStore() {
 beforeEach(() => {
   resetStore()
   updateAction.mockReset()
+  setDraftAction.mockReset()
+  clearDraftAction.mockReset()
 })
 
 afterEach(() => {
@@ -85,6 +96,130 @@ describe('useUserSettingsStore', () => {
     expect(updateAction).not.toHaveBeenCalled()
   })
 
+  it('setPendingSprintDraft persists draft lokaal (session-only, geen server-call)', async () => {
+    useUserSettingsStore.getState().hydrate({}, false)
+
+    const draft: PendingSprintDraft = {
+      goal: 'Sprint 1',
+      pbiIntent: { pbiA: 'all' },
+      storyOverrides: {},
+    }
+    await useUserSettingsStore
+      .getState()
+      .setPendingSprintDraft('product-1', draft)
+
+    const s = useUserSettingsStore.getState()
+    expect(
+      s.entities.settings.workflow?.pendingSprintDraft?.['product-1'],
+    ).toMatchObject({ goal: 'Sprint 1' })
+    expect(setDraftAction).not.toHaveBeenCalled()
+  })
+
+  it('hydrate strips workflow.pendingSprintDraft uit legacy server-state', () => {
+    useUserSettingsStore.getState().hydrate(
+      {
+        workflow: {
+          pendingSprintDraft: {
+            'product-1': {
+              goal: 'Legacy draft',
+              pbiIntent: {},
+              storyOverrides: {},
+            },
+          },
+        },
+      },
+      false,
+    )
+
+    const s = useUserSettingsStore.getState()
+    expect(s.entities.settings.workflow?.pendingSprintDraft).toBeUndefined()
+  })
+
+  it('clearPendingSprintDraft verwijdert de key lokaal zonder server-call', async () => {
+    useUserSettingsStore.getState().hydrate({}, false)
+    await useUserSettingsStore.getState().setPendingSprintDraft('product-1', {
+      goal: 'Old',
+      pbiIntent: {},
+      storyOverrides: {},
+    })
+
+    await useUserSettingsStore
+      .getState()
+      .clearPendingSprintDraft('product-1')
+
+    const s = useUserSettingsStore.getState()
+    expect(
+      s.entities.settings.workflow?.pendingSprintDraft?.['product-1'],
+    ).toBeUndefined()
+    expect(clearDraftAction).not.toHaveBeenCalled()
+  })
+
+  it('upsertPbiIntent updates intent and wipes storyOverrides for that PBI', async () => {
+    useUserSettingsStore.getState().hydrate({}, false)
+    await useUserSettingsStore.getState().setPendingSprintDraft('product-1', {
+      goal: 'g',
+      pbiIntent: { pbiA: 'none' },
+      storyOverrides: {
+        pbiA: { add: ['s-1'], remove: [] },
+        pbiB: { add: [], remove: ['s-2'] },
+      },
+    })
+
+    await useUserSettingsStore
+      .getState()
+      .upsertPbiIntent('product-1', 'pbiA', 'all')
+
+    const draft =
+      useUserSettingsStore.getState().entities.settings.workflow
+        ?.pendingSprintDraft?.['product-1']
+    expect(draft?.pbiIntent.pbiA).toBe('all')
+    expect(draft?.storyOverrides.pbiA).toBeUndefined()
+    expect(draft?.storyOverrides.pbiB).toEqual({ add: [], remove: ['s-2'] })
+  })
+
+  it('upsertStoryOverride add adds to add[] and removes from remove[]', async () => {
+    useUserSettingsStore.getState().hydrate({}, false)
+    await useUserSettingsStore.getState().setPendingSprintDraft('product-1', {
+      goal: 'g',
+      pbiIntent: {},
+      storyOverrides: {
+        pbiA: { add: [], remove: ['story-1'] },
+      },
+    })
+
+    await useUserSettingsStore
+      .getState()
+      .upsertStoryOverride('product-1', 'pbiA', 'story-1', 'add')
+
+    const draft =
+      useUserSettingsStore.getState().entities.settings.workflow
+        ?.pendingSprintDraft?.['product-1']
+    expect(draft?.storyOverrides.pbiA).toEqual({
+      add: ['story-1'],
+      remove: [],
+    })
+  })
+
+  it('upsertStoryOverride clear removes from both arrays and drops empty entry', async () => {
+    useUserSettingsStore.getState().hydrate({}, false)
+    await useUserSettingsStore.getState().setPendingSprintDraft('product-1', {
+      goal: 'g',
+      pbiIntent: {},
+      storyOverrides: {
+        pbiA: { add: ['story-1'], remove: [] },
+      },
+    })
+
+    await useUserSettingsStore
+      .getState()
+      .upsertStoryOverride('product-1', 'pbiA', 'story-1', 'clear')
+
+    const draft =
+      useUserSettingsStore.getState().entities.settings.workflow
+        ?.pendingSprintDraft?.['product-1']
+    expect(draft?.storyOverrides.pbiA).toBeUndefined()
+  })
+
   it('applyServerPatch merges without optimistic state', () => {
     useUserSettingsStore.getState().hydrate(
       { views: { sprintBacklog: { sort: 'code' } } },

actions/active-sprint.ts

@@ -7,7 +7,11 @@ import { z } from 'zod'
 import { prisma } from '@/lib/prisma'
 import { SessionData, sessionOptions } from '@/lib/session'
 import { productAccessFilter } from '@/lib/product-access'
-import { setActiveSprintInSettings } from '@/lib/active-sprint'
+import {
+  clearActiveSprintInSettings,
+  setActiveSelectionInSettings,
+  setActiveSprintInSettings,
+} from '@/lib/active-sprint'
 
 async function getSession() {
   return getIronSession<SessionData>(await cookies(), sessionOptions)
@@ -18,6 +22,10 @@ const setSchema = z.object({
   sprintId: z.string().min(1),
 })
 
+const clearSchema = z.object({
+  productId: z.string().min(1),
+})
+
 export async function setActiveSprintAction(productId: string, sprintId: string) {
   const session = await getSession()
   if (!session.userId) return { error: 'Niet ingelogd' }
@@ -41,6 +49,99 @@ export async function setActiveSprintAction(productId: string, sprintId: string)
   return { success: true, sprintId: parsed.data.sprintId }
 }
 
+export async function clearActiveSprintAction(productId: string) {
+  const session = await getSession()
+  if (!session.userId) return { error: 'Niet ingelogd' }
+  if (session.isDemo) return { error: 'Niet beschikbaar in demo-modus' }
+
+  const parsed = clearSchema.safeParse({ productId })
+  if (!parsed.success) return { error: 'Ongeldig product-id' }
+
+  const product = await prisma.product.findFirst({
+    where: { id: parsed.data.productId, ...productAccessFilter(session.userId) },
+    select: { id: true },
+  })
+  if (!product) return { error: 'Product niet gevonden of niet toegankelijk' }
+
+  await clearActiveSprintInSettings(session.userId, parsed.data.productId)
+  revalidatePath('/', 'layout')
+  return { success: true }
+}
+
+const selectionSchema = z.object({
+  productId: z.string().min(1),
+  sprintId: z.string().min(1),
+})
+
+/**
+ * PBI-79: kies een sprint en auto-select zijn enige PBI/story (indien
+ * singleton). Resultaat wordt server-side bepaald + atomair in user-settings
+ * weggeschreven (sprint+pbi+story) zodat cross-device-restore klopt.
+ */
+export async function switchActiveSprintAction(
+  productId: string,
+  sprintId: string,
+): Promise<
+  | {
+      success: true
+      sprintId: string
+      pbiId: string | null
+      storyId: string | null
+    }
+  | { error: string }
+> {
+  const session = await getSession()
+  if (!session.userId) return { error: 'Niet ingelogd' }
+  if (session.isDemo) return { error: 'Niet beschikbaar in demo-modus' }
+
+  const parsed = selectionSchema.safeParse({ productId, sprintId })
+  if (!parsed.success) return { error: 'Ongeldig product- of sprint-id' }
+
+  const sprint = await prisma.sprint.findFirst({
+    where: {
+      id: parsed.data.sprintId,
+      product_id: parsed.data.productId,
+      product: productAccessFilter(session.userId),
+    },
+    select: { id: true },
+  })
+  if (!sprint) return { error: 'Sprint niet gevonden of niet toegankelijk' }
+
+  // Auto-select: alleen wanneer sprint exact één PBI heeft. Story-auto-select
+  // alleen wanneer die PBI exact één story binnen deze sprint heeft.
+  const sprintStories = await prisma.story.findMany({
+    where: {
+      sprint_id: parsed.data.sprintId,
+      product_id: parsed.data.productId,
+    },
+    select: { id: true, pbi_id: true },
+  })
+  const uniquePbiIds = Array.from(new Set(sprintStories.map((s) => s.pbi_id)))
+  let autoPbiId: string | null = null
+  let autoStoryId: string | null = null
+  if (uniquePbiIds.length === 1) {
+    autoPbiId = uniquePbiIds[0]
+    const storiesForPbi = sprintStories.filter((s) => s.pbi_id === autoPbiId)
+    if (storiesForPbi.length === 1) {
+      autoStoryId = storiesForPbi[0].id
+    }
+  }
+
+  await setActiveSelectionInSettings(session.userId, parsed.data.productId, {
+    sprintId: parsed.data.sprintId,
+    pbiId: autoPbiId,
+    storyId: autoStoryId,
+  })
+  revalidatePath('/', 'layout')
+
+  return {
+    success: true,
+    sprintId: parsed.data.sprintId,
+    pbiId: autoPbiId,
+    storyId: autoStoryId,
+  }
+}
+
 export async function syncActiveSprintCookieAction(productId: string, sprintId: string) {
   const session = await getSession()
   if (!session.userId) return

actions/sprint-draft.ts

@@ -0,0 +1,121 @@
+'use server'
+
+import { revalidatePath } from 'next/cache'
+import { cookies } from 'next/headers'
+import { getIronSession } from 'iron-session'
+import { z } from 'zod'
+import type { Prisma } from '@prisma/client'
+import { prisma } from '@/lib/prisma'
+import { SessionData, sessionOptions } from '@/lib/session'
+import { productAccessFilter } from '@/lib/product-access'
+import {
+  mergeSettings,
+  parseUserSettings,
+  type PendingSprintDraft,
+  type UserSettings,
+} from '@/lib/user-settings'
+
+async function getSession() {
+  return getIronSession<SessionData>(await cookies(), sessionOptions)
+}
+
+const StoryOverridesSchema = z.object({
+  add: z.array(z.string()),
+  remove: z.array(z.string()),
+}).strict()
+
+const DraftSchema = z.object({
+  goal: z.string().min(1),
+  startAt: z.string().date().optional(),
+  endAt: z.string().date().optional(),
+  pbiIntent: z.record(z.string(), z.enum(['all', 'none'])).default({}),
+  storyOverrides: z.record(z.string(), StoryOverridesSchema).default({}),
+}).strict()
+
+const SetSchema = z.object({
+  productId: z.string().min(1),
+  draft: DraftSchema,
+})
+
+const ClearSchema = z.object({
+  productId: z.string().min(1),
+})
+
+async function ensureProductAccess(userId: string, productId: string) {
+  return prisma.product.findFirst({
+    where: { id: productId, ...productAccessFilter(userId) },
+    select: { id: true },
+  })
+}
+
+async function readUserSettings(userId: string): Promise<UserSettings> {
+  const user = await prisma.user.findUnique({
+    where: { id: userId },
+    select: { settings: true },
+  })
+  return parseUserSettings(user?.settings)
+}
+
+async function writeUserSettings(userId: string, next: UserSettings) {
+  await prisma.user.update({
+    where: { id: userId },
+    data: { settings: next as unknown as Prisma.InputJsonValue },
+  })
+}
+
+export async function setPendingSprintDraftAction(
+  productId: string,
+  draft: PendingSprintDraft,
+) {
+  const session = await getSession()
+  if (!session.userId) return { error: 'Niet ingelogd' }
+  if (session.isDemo) return { error: 'Niet beschikbaar in demo-modus' }
+
+  const parsed = SetSchema.safeParse({ productId, draft })
+  if (!parsed.success) {
+    return { error: 'Ongeldige draft', issues: parsed.error.issues }
+  }
+
+  const product = await ensureProductAccess(session.userId, parsed.data.productId)
+  if (!product) return { error: 'Product niet gevonden of niet toegankelijk' }
+
+  const current = await readUserSettings(session.userId)
+  const patch: Partial<UserSettings> = {
+    workflow: {
+      pendingSprintDraft: {
+        ...(current.workflow?.pendingSprintDraft ?? {}),
+        [parsed.data.productId]: parsed.data.draft,
+      },
+    },
+  }
+  await writeUserSettings(session.userId, mergeSettings(current, patch))
+  revalidatePath('/', 'layout')
+  return { success: true }
+}
+
+export async function clearPendingSprintDraftAction(productId: string) {
+  const session = await getSession()
+  if (!session.userId) return { error: 'Niet ingelogd' }
+  if (session.isDemo) return { error: 'Niet beschikbaar in demo-modus' }
+
+  const parsed = ClearSchema.safeParse({ productId })
+  if (!parsed.success) return { error: 'Ongeldig product-id' }
+
+  const product = await ensureProductAccess(session.userId, parsed.data.productId)
+  if (!product) return { error: 'Product niet gevonden of niet toegankelijk' }
+
+  const current = await readUserSettings(session.userId)
+  const existingMap = current.workflow?.pendingSprintDraft
+  if (!existingMap || !(parsed.data.productId in existingMap)) {
+    return { success: true }
+  }
+  const nextMap = { ...existingMap }
+  delete nextMap[parsed.data.productId]
+  const next: UserSettings = {
+    ...current,
+    workflow: { ...current.workflow, pendingSprintDraft: nextMap },
+  }
+  await writeUserSettings(session.userId, next)
+  revalidatePath('/', 'layout')
+  return { success: true }
+}

actions/sprints.ts

@@ -15,8 +15,358 @@ import { enforceUserRateLimit } from '@/lib/rate-limit'
 import { propagateStatusUpwards } from '@/lib/tasks-status-update'
 import { createWithCodeRetry, generateNextSprintCode } from '@/lib/code-server'
 import { setActiveSprintInSettings } from '@/lib/active-sprint'
+import { partitionByEligibility } from '@/lib/sprint-conflicts'
 import { z } from 'zod'
 
+const StoryOverrideSchema = z.object({
+  add: z.array(z.string()),
+  remove: z.array(z.string()),
+})
+
+const createSprintWithSelectionSchema = z.object({
+  productId: z.string().min(1),
+  metadata: z.object({
+    goal: z.string().min(1).max(2000),
+    startAt: z.string().date().optional(),
+    endAt: z.string().date().optional(),
+  }),
+  pbiIntent: z.record(z.string(), z.enum(['all', 'none'])).default({}),
+  storyOverrides: z.record(z.string(), StoryOverrideSchema).default({}),
+})
+
+export type CreateSprintWithSelectionInput = z.infer<
+  typeof createSprintWithSelectionSchema
+>
+
+type SprintCreateConflicts = {
+  notEligible: { storyId: string; reason: 'DONE' | 'IN_OTHER_SPRINT' }[]
+  crossSprint: { storyId: string; sprintId: string; sprintName: string }[]
+}
+
+export type CreateSprintWithSelectionResult =
+  | {
+      success: true
+      sprintId: string
+      affectedStoryIds: string[]
+      affectedPbiIds: string[]
+      affectedTaskIds: string[]
+      conflicts: SprintCreateConflicts
+    }
+  | { error: string; code: number }
+
+const updateSprintSchema = z.object({
+  sprintId: z.string().min(1),
+  fields: z
+    .object({
+      goal: z.string().min(1).max(2000).optional(),
+      startAt: z.string().date().nullable().optional(),
+      endAt: z.string().date().nullable().optional(),
+    })
+    .refine(
+      (data) => Object.keys(data).length > 0,
+      'Minstens één veld vereist',
+    ),
+})
+
+export type UpdateSprintInput = z.infer<typeof updateSprintSchema>
+
+export type UpdateSprintResult =
+  | { success: true; sprintId: string }
+  | { error: string; code: number }
+
+export async function updateSprintAction(
+  input: UpdateSprintInput,
+): Promise<UpdateSprintResult> {
+  const session = await getSession()
+  if (!session.userId) return { error: 'Niet ingelogd', code: 403 }
+  if (session.isDemo) return { error: 'Niet beschikbaar in demo-modus', code: 403 }
+
+  const parsed = updateSprintSchema.safeParse(input)
+  if (!parsed.success) return { error: 'Validatie mislukt', code: 422 }
+
+  const sprint = await prisma.sprint.findFirst({
+    where: {
+      id: parsed.data.sprintId,
+      product: productAccessFilter(session.userId),
+    },
+    select: { id: true, product_id: true },
+  })
+  if (!sprint) return { error: 'Sprint niet gevonden', code: 403 }
+
+  const data: { sprint_goal?: string; start_date?: Date | null; end_date?: Date | null } = {}
+  if (parsed.data.fields.goal !== undefined) {
+    data.sprint_goal = parsed.data.fields.goal
+  }
+  if (parsed.data.fields.startAt !== undefined) {
+    data.start_date = parseDate(parsed.data.fields.startAt)
+  }
+  if (parsed.data.fields.endAt !== undefined) {
+    data.end_date = parseDate(parsed.data.fields.endAt)
+  }
+
+  await prisma.sprint.update({
+    where: { id: parsed.data.sprintId },
+    data,
+  })
+  revalidatePath(`/products/${sprint.product_id}`, 'layout')
+
+  return { success: true, sprintId: parsed.data.sprintId }
+}
+
+const commitSprintMembershipSchema = z.object({
+  activeSprintId: z.string().min(1),
+  adds: z.array(z.string()),
+  removes: z.array(z.string()),
+})
+
+export type CommitSprintMembershipInput = z.infer<
+  typeof commitSprintMembershipSchema
+>
+
+type CommitConflicts = {
+  notEligible: { storyId: string; reason: 'DONE' | 'IN_OTHER_SPRINT' }[]
+  alreadyRemoved: string[]
+}
+
+export type CommitSprintMembershipResult =
+  | {
+      success: true
+      affectedStoryIds: string[]
+      affectedPbiIds: string[]
+      affectedTaskIds: string[]
+      conflicts: CommitConflicts
+    }
+  | { error: string; code: number }
+
+export async function commitSprintMembershipAction(
+  input: CommitSprintMembershipInput,
+): Promise<CommitSprintMembershipResult> {
+  const session = await getSession()
+  if (!session.userId) return { error: 'Niet ingelogd', code: 403 }
+  if (session.isDemo) return { error: 'Niet beschikbaar in demo-modus', code: 403 }
+
+  const parsed = commitSprintMembershipSchema.safeParse(input)
+  if (!parsed.success) return { error: 'Validatie mislukt', code: 422 }
+
+  // Sprint moet bestaan en bereikbaar zijn via product-access.
+  const sprint = await prisma.sprint.findFirst({
+    where: {
+      id: parsed.data.activeSprintId,
+      product: productAccessFilter(session.userId),
+    },
+    select: { id: true, product_id: true },
+  })
+  if (!sprint) {
+    return { error: 'Sprint niet gevonden of niet toegankelijk', code: 403 }
+  }
+
+  // Filter adds via eligibility (sprint_id IS NULL en niet DONE; andere OPEN
+  // sprint → conflicts.notEligible + crossSprint).
+  const addPartition = await partitionByEligibility(
+    prisma,
+    parsed.data.adds,
+    parsed.data.activeSprintId,
+  )
+  const eligibleAdds = addPartition.eligible
+  const notEligibleAdds = addPartition.notEligible
+
+  // Race-safety voor removes: alleen stories die feitelijk in de actieve
+  // sprint zitten worden verwijderd.
+  const removeRows =
+    parsed.data.removes.length > 0
+      ? await prisma.story.findMany({
+          where: {
+            id: { in: parsed.data.removes },
+            sprint_id: parsed.data.activeSprintId,
+          },
+          select: { id: true },
+        })
+      : []
+  const validRemoves = removeRows.map((r) => r.id)
+  const validRemoveSet = new Set(validRemoves)
+  const alreadyRemoved = parsed.data.removes.filter(
+    (id) => !validRemoveSet.has(id),
+  )
+
+  if (eligibleAdds.length === 0 && validRemoves.length === 0) {
+    // Geen werk te doen — geef toch een success-shape terug zodat de client
+    // pending buffer kan resetten + conflicts kan tonen.
+    return {
+      success: true,
+      affectedStoryIds: [],
+      affectedPbiIds: [],
+      affectedTaskIds: [],
+      conflicts: { notEligible: notEligibleAdds, alreadyRemoved },
+    }
+  }
+
+  await prisma.$transaction(async (tx) => {
+    if (eligibleAdds.length > 0) {
+      await tx.story.updateMany({
+        where: { id: { in: eligibleAdds } },
+        data: { sprint_id: parsed.data.activeSprintId, status: 'IN_SPRINT' },
+      })
+      await tx.task.updateMany({
+        where: { story_id: { in: eligibleAdds } },
+        data: { sprint_id: parsed.data.activeSprintId },
+      })
+    }
+    if (validRemoves.length > 0) {
+      await tx.story.updateMany({
+        where: { id: { in: validRemoves } },
+        data: { sprint_id: null, status: 'OPEN' },
+      })
+      await tx.task.updateMany({
+        where: { story_id: { in: validRemoves } },
+        data: { sprint_id: null },
+      })
+    }
+  })
+
+  const affectedStoryIds = [...eligibleAdds, ...validRemoves]
+  const affectedStories =
+    affectedStoryIds.length > 0
+      ? await prisma.story.findMany({
+          where: { id: { in: affectedStoryIds } },
+          select: { pbi_id: true },
+        })
+      : []
+  const affectedPbiIds = Array.from(
+    new Set(affectedStories.map((s) => s.pbi_id)),
+  )
+  const affectedTasks =
+    affectedStoryIds.length > 0
+      ? await prisma.task.findMany({
+          where: { story_id: { in: affectedStoryIds } },
+          select: { id: true },
+        })
+      : []
+  const affectedTaskIds = affectedTasks.map((t) => t.id)
+
+  revalidatePath(`/products/${sprint.product_id}`, 'layout')
+
+  return {
+    success: true,
+    affectedStoryIds,
+    affectedPbiIds,
+    affectedTaskIds,
+    conflicts: { notEligible: notEligibleAdds, alreadyRemoved },
+  }
+}
+
+export async function createSprintWithSelectionAction(
+  input: CreateSprintWithSelectionInput,
+): Promise<CreateSprintWithSelectionResult> {
+  const session = await getSession()
+  if (!session.userId) return { error: 'Niet ingelogd', code: 403 }
+  if (session.isDemo) return { error: 'Niet beschikbaar in demo-modus', code: 403 }
+
+  const limited = enforceUserRateLimit('create-sprint', session.userId)
+  if (limited) return { error: limited.error, code: limited.code }
+
+  const parsed = createSprintWithSelectionSchema.safeParse(input)
+  if (!parsed.success) return { error: 'Validatie mislukt', code: 422 }
+
+  const product = await getAccessibleProduct(parsed.data.productId, session.userId)
+  if (!product) return { error: 'Product niet gevonden', code: 403 }
+
+  // Resolveer intent + per-PBI overrides naar concrete story-IDs.
+  const allPbiAllIds = Object.entries(parsed.data.pbiIntent)
+    .filter(([, intent]) => intent === 'all')
+    .map(([pbiId]) => pbiId)
+
+  // Stap 1: alle child-stories voor PBI's met intent='all'.
+  let candidate: string[] = []
+  if (allPbiAllIds.length > 0) {
+    const rows = await prisma.story.findMany({
+      where: { pbi_id: { in: allPbiAllIds }, product_id: parsed.data.productId },
+      select: { id: true, pbi_id: true },
+    })
+    const removedSet = new Set<string>()
+    for (const [pbiId, override] of Object.entries(parsed.data.storyOverrides)) {
+      for (const id of override.remove) removedSet.add(`${pbiId}:${id}`)
+    }
+    candidate = rows
+      .filter((row) => !removedSet.has(`${row.pbi_id}:${row.id}`))
+      .map((row) => row.id)
+  }
+
+  // Stap 2: storyOverrides.add — werkt voor zowel intent='none' als 'all' (extra
+  // toevoegingen). Dedupliceren met candidates uit stap 1.
+  const candidateSet = new Set(candidate)
+  for (const override of Object.values(parsed.data.storyOverrides)) {
+    for (const id of override.add) candidateSet.add(id)
+  }
+  const candidateIds = Array.from(candidateSet)
+
+  // Eligibility-filter (incl. cross-sprint guard).
+  const partition = await partitionByEligibility(prisma, candidateIds)
+
+  if (partition.eligible.length === 0) {
+    return {
+      error: 'Geen eligible stories voor deze sprint',
+      code: 422,
+    }
+  }
+
+  const sprint = await createWithCodeRetry(
+    () => generateNextSprintCode(parsed.data.productId),
+    (code) =>
+      prisma.$transaction(async (tx) => {
+        const created = await tx.sprint.create({
+          data: {
+            product_id: parsed.data.productId,
+            code,
+            sprint_goal: parsed.data.metadata.goal,
+            status: 'OPEN',
+            start_date: parseDate(parsed.data.metadata.startAt),
+            end_date: parseDate(parsed.data.metadata.endAt),
+          },
+        })
+        await tx.story.updateMany({
+          where: { id: { in: partition.eligible } },
+          data: { sprint_id: created.id, status: 'IN_SPRINT' },
+        })
+        await tx.task.updateMany({
+          where: { story_id: { in: partition.eligible } },
+          data: { sprint_id: created.id },
+        })
+        return created
+      }),
+  )
+
+  // Snapshot affected pbi/task IDs voor client-store patches.
+  const affectedStories = await prisma.story.findMany({
+    where: { id: { in: partition.eligible } },
+    select: { pbi_id: true },
+  })
+  const affectedPbiIds = Array.from(new Set(affectedStories.map((s) => s.pbi_id)))
+  const affectedTasks = await prisma.task.findMany({
+    where: { story_id: { in: partition.eligible } },
+    select: { id: true },
+  })
+  const affectedTaskIds = affectedTasks.map((t) => t.id)
+
+  await setActiveSprintInSettings(
+    session.userId,
+    parsed.data.productId,
+    sprint.id,
+  )
+  revalidatePath(`/products/${parsed.data.productId}`, 'layout')
+
+  return {
+    success: true,
+    sprintId: sprint.id,
+    affectedStoryIds: partition.eligible,
+    affectedPbiIds,
+    affectedTaskIds,
+    conflicts: {
+      notEligible: partition.notEligible,
+      crossSprint: partition.crossSprint,
+    },
+  }
+}
+
 async function getSession() {
   return getIronSession<SessionData>(await cookies(), sessionOptions)
 }
@@ -53,10 +403,10 @@ export async function createSprintAction(_prevState: unknown, formData: FormData
   const product = await getAccessibleProduct(parsed.data.productId, session.userId)
   if (!product) return { error: 'Product niet gevonden', code: 403 }
 
-  const existing = await prisma.sprint.findFirst({
-    where: { product_id: parsed.data.productId, status: 'OPEN' },
-  })
-  if (existing) return { error: 'Er is al een actieve Sprint voor dit product', sprintId: existing.id, code: 422 }
+  // PBI-79 / ST-1342: multi-OPEN sprints toegestaan. Bestaande OPEN sprints
+  // op hetzelfde product zijn geen reden meer om aanmaak te blokkeren —
+  // cross-sprint-conflicts worden per-story afgevangen in de membership-
+  // commit-flow.
 
   const sprint = await createWithCodeRetry(
     () => generateNextSprintCode(parsed.data.productId),

app/(app)/products/[id]/page.tsx

@@ -15,7 +15,11 @@ import { UrlTaskSync } from '@/components/backlog/url-task-sync'
 import { TaskDialog } from '@/app/_components/tasks/task-dialog'
 import { EditTaskLoader } from '@/app/_components/tasks/edit-task-loader'
 import { TaskDialogSkeleton } from '@/app/_components/tasks/task-dialog-skeleton'
-import { StartSprintButton } from '@/components/sprint/start-sprint-button'
+import { NewSprintTrigger } from '@/components/backlog/new-sprint-trigger'
+import { SprintDraftBanner } from '@/components/backlog/sprint-draft-banner'
+import { SprintDraftLeaveGuard } from '@/components/backlog/sprint-draft-leave-guard'
+import { SaveSprintButton } from '@/components/backlog/save-sprint-button'
+import { ActiveSelectionHydrator } from '@/components/backlog/active-selection-hydrator'
 import { ActivateProductButton } from '@/components/shared/activate-product-button'
 import { EditProductButton } from '@/components/products/edit-product-button'
 import { SprintSwitcher } from '@/components/shared/sprint-switcher'
@@ -118,13 +122,15 @@ export default async function ProductBacklogPage({ params, searchParams }: Props
           {!isActiveProduct && (
             <ActivateProductButton productId={id} isDemo={isDemo} redirectTo={`/products/${id}`} />
           )}
-          {hasOpenSprint ? (
+          {hasOpenSprint && (
             <Link href={`/products/${id}/sprint`} className="text-xs text-primary hover:underline font-medium">
               Sprint actief →
             </Link>
-          ) : (
-            !isDemo && <StartSprintButton productId={id} />
           )}
+          {activeSprintItem && !isDemo && (
+            <SaveSprintButton activeSprintId={activeSprintItem.id} />
+          )}
+          {!isDemo && <NewSprintTrigger productId={id} isDemo={isDemo} />}
           {!isDemo && product.user_id === session.userId && (
             <EditProductButton
               product={{
@@ -147,6 +153,10 @@ export default async function ProductBacklogPage({ params, searchParams }: Props
         </div>
       </div>
 
+      {/* Sprint definition banner (state A′) + beforeunload-guard */}
+      <SprintDraftBanner productId={id} />
+      <SprintDraftLeaveGuard productId={id} />
+
       {/* Split pane */}
       <div className="flex-1 overflow-hidden">
         <BacklogHydrationWrapper
@@ -159,6 +169,7 @@ export default async function ProductBacklogPage({ params, searchParams }: Props
           }}
         >
           <UrlTaskSync />
+          <ActiveSelectionHydrator productId={id} />
           <BacklogSplitPane
             cookieKey={`backlog-${id}`}
             defaultSplit={[20, 45, 35]}
@@ -168,11 +179,13 @@ export default async function ProductBacklogPage({ params, searchParams }: Props
                 key="pbi"
                 productId={id}
                 isDemo={isDemo}
+                activeSprintId={activeSprintItem?.id ?? null}
               />,
               <StoryPanel
                 key="story"
                 productId={id}
                 isDemo={isDemo}
+                activeSprintId={activeSprintItem?.id ?? null}
               />,
               <TaskPanel
                 key="tasks"

app/api/products/[id]/cross-sprint-blocks/route.ts

@@ -0,0 +1,74 @@
+// PBI-79 / T-929: GET /api/products/:id/cross-sprint-blocks
+//
+// Lichte UX-hint voor disabled-vinkjes: welke stories binnen pbiIds zitten in
+// een andere OPEN sprint (excludeSprintId expliciet uitgesloten). Server-side
+// commit-actions blijven autoritatief — dit endpoint is alleen voor UI.
+import { authenticateApiRequest } from '@/lib/api-auth'
+import { prisma } from '@/lib/prisma'
+import { productAccessFilter } from '@/lib/product-access'
+
+export const dynamic = 'force-dynamic'
+
+function parsePbiIds(raw: string | null): string[] | null {
+  if (!raw) return null
+  const ids = raw
+    .split(',')
+    .map((s) => s.trim())
+    .filter(Boolean)
+  return ids.length === 0 ? null : ids
+}
+
+export async function GET(
+  request: Request,
+  { params }: { params: Promise<{ id: string }> },
+) {
+  const auth = await authenticateApiRequest(request)
+  if ('error' in auth) {
+    return Response.json({ error: auth.error }, { status: auth.status })
+  }
+
+  const { id: productId } = await params
+  const url = new URL(request.url)
+  const excludeSprintId = url.searchParams.get('excludeSprintId') ?? undefined
+  const pbiIds = parsePbiIds(url.searchParams.get('pbiIds'))
+
+  if (!pbiIds) {
+    return Response.json(
+      { error: 'pbiIds is verplicht (comma-separated)' },
+      { status: 400 },
+    )
+  }
+
+  const product = await prisma.product.findFirst({
+    where: { id: productId, ...productAccessFilter(auth.userId) },
+    select: { id: true },
+  })
+  if (!product) {
+    return Response.json({ error: 'Product niet gevonden' }, { status: 404 })
+  }
+
+  const stories = await prisma.story.findMany({
+    where: {
+      pbi_id: { in: pbiIds },
+      product_id: productId,
+      sprint_id: { not: null },
+      ...(excludeSprintId ? { NOT: { sprint_id: excludeSprintId } } : {}),
+      sprint: { status: 'OPEN' },
+    },
+    select: {
+      id: true,
+      sprint: { select: { id: true, code: true } },
+    },
+  })
+
+  const result: Record<string, { sprintId: string; sprintName: string }> = {}
+  for (const story of stories) {
+    if (!story.sprint) continue
+    result[story.id] = {
+      sprintId: story.sprint.id,
+      sprintName: story.sprint.code,
+    }
+  }
+
+  return Response.json(result)
+}

app/api/products/[id]/sprint-membership-summary/route.ts

@@ -0,0 +1,87 @@
+// PBI-79 / T-928: GET /api/products/:id/sprint-membership-summary
+//
+// Levert per PBI {total, inSprint} counts, gescoped op de doorgegeven pbiIds.
+// Endpoint weigert product-brede aanroepen (pbiIds is verplicht). Eén groupBy
+// + één count-by-sprint waar pbi_id IN (pbiIds).
+import { authenticateApiRequest } from '@/lib/api-auth'
+import { prisma } from '@/lib/prisma'
+import { productAccessFilter } from '@/lib/product-access'
+
+export const dynamic = 'force-dynamic'
+
+function parsePbiIds(raw: string | null): string[] | null {
+  if (!raw) return null
+  const ids = raw
+    .split(',')
+    .map((s) => s.trim())
+    .filter(Boolean)
+  return ids.length === 0 ? null : ids
+}
+
+export async function GET(
+  request: Request,
+  { params }: { params: Promise<{ id: string }> },
+) {
+  const auth = await authenticateApiRequest(request)
+  if ('error' in auth) {
+    return Response.json({ error: auth.error }, { status: auth.status })
+  }
+
+  const { id: productId } = await params
+  const url = new URL(request.url)
+  const sprintId = url.searchParams.get('sprintId')
+  const pbiIds = parsePbiIds(url.searchParams.get('pbiIds'))
+
+  if (!sprintId) {
+    return Response.json({ error: 'sprintId is verplicht' }, { status: 400 })
+  }
+  if (!pbiIds) {
+    return Response.json(
+      { error: 'pbiIds is verplicht (comma-separated)' },
+      { status: 400 },
+    )
+  }
+
+  const product = await prisma.product.findFirst({
+    where: { id: productId, ...productAccessFilter(auth.userId) },
+    select: { id: true },
+  })
+  if (!product) {
+    return Response.json({ error: 'Product niet gevonden' }, { status: 404 })
+  }
+
+  const [totals, inSprint] = await Promise.all([
+    prisma.story.groupBy({
+      by: ['pbi_id'],
+      where: { pbi_id: { in: pbiIds }, product_id: productId },
+      _count: { _all: true },
+    }),
+    prisma.story.groupBy({
+      by: ['pbi_id'],
+      where: {
+        pbi_id: { in: pbiIds },
+        product_id: productId,
+        sprint_id: sprintId,
+      },
+      _count: { _all: true },
+    }),
+  ])
+
+  const inSprintByPbi = new Map<string, number>()
+  for (const row of inSprint) {
+    inSprintByPbi.set(row.pbi_id, row._count._all)
+  }
+
+  const result: Record<string, { total: number; inSprint: number }> = {}
+  for (const pbiId of pbiIds) {
+    result[pbiId] = { total: 0, inSprint: inSprintByPbi.get(pbiId) ?? 0 }
+  }
+  for (const row of totals) {
+    result[row.pbi_id] = {
+      total: row._count._all,
+      inSprint: inSprintByPbi.get(row.pbi_id) ?? 0,
+    }
+  }
+
+  return Response.json(result)
+}

components/backlog/active-selection-hydrator.tsx

@@ -0,0 +1,53 @@
+'use client'
+
+import { useEffect } from 'react'
+import { useUserSettingsStore } from '@/stores/user-settings/store'
+import { useProductWorkspaceStore } from '@/stores/product-workspace/store'
+
+interface ActiveSelectionHydratorProps {
+  productId: string
+}
+
+/**
+ * PBI-79: hydrateert de workspace-store met de actieve PBI/story die in
+ * user-settings staan opgeslagen. Loopt na elke (re)hydratatie en bij
+ * mutaties van de user-settings (bv. na sprint-switch). Wint van de
+ * localStorage hint-restore — user-settings is de cross-device source of
+ * truth.
+ */
+export function ActiveSelectionHydrator({ productId }: ActiveSelectionHydratorProps) {
+  const hydrated = useUserSettingsStore((s) => s.context.hydrated)
+  const persistedPbiId = useUserSettingsStore(
+    (s) => s.entities.settings.layout?.activePbis?.[productId] ?? undefined,
+  )
+  const persistedStoryId = useUserSettingsStore(
+    (s) => s.entities.settings.layout?.activeStories?.[productId] ?? undefined,
+  )
+
+  useEffect(() => {
+    if (!hydrated) return
+    const store = useProductWorkspaceStore.getState()
+    // Schrijf alleen wanneer user-settings expliciet iets gekozen heeft
+    // (key aanwezig met string-waarde). null-key betekent 'bewust leeg' →
+    // we wissen lokale state. undefined-key (geen voorkeur) → niets doen.
+    if (persistedPbiId === undefined && persistedStoryId === undefined) return
+
+    if (persistedPbiId === null) {
+      store.setActivePbi(null)
+      return
+    }
+    if (persistedPbiId && store.context.activePbiId !== persistedPbiId) {
+      store.setActivePbi(persistedPbiId)
+    }
+    if (persistedStoryId && store.context.activeStoryId !== persistedStoryId) {
+      // setActivePbi triggert async cascade-restore die de oude hint kan
+      // herstellen; de daarop volgende setActiveStory bumpt activeRequestId
+      // en ongeldigt de cascade.
+      store.setActiveStory(persistedStoryId)
+    } else if (persistedStoryId === null) {
+      store.setActiveStory(null)
+    }
+  }, [hydrated, persistedPbiId, persistedStoryId])
+
+  return null
+}

components/backlog/new-sprint-metadata-dialog.tsx

@@ -0,0 +1,203 @@
+'use client'
+
+import { useRef, useState, useTransition } from 'react'
+import { toast } from 'sonner'
+import { Button } from '@/components/ui/button'
+import { Textarea } from '@/components/ui/textarea'
+import { Dialog, DialogContent, DialogTitle } from '@/components/ui/dialog'
+import {
+  useDirtyCloseGuard,
+  DirtyCloseGuardDialog,
+} from '@/components/shared/use-dirty-close-guard'
+import { useDialogSubmitShortcut } from '@/components/shared/use-dialog-submit-shortcut'
+import {
+  entityDialogContentClasses,
+  entityDialogFooterClasses,
+  entityDialogHeaderClasses,
+} from '@/components/shared/entity-dialog-layout'
+import { useUserSettingsStore } from '@/stores/user-settings/store'
+import { debugProps } from '@/lib/debug'
+
+interface NewSprintMetadataDialogProps {
+  open: boolean
+  productId: string
+  onOpenChange: (open: boolean) => void
+}
+
+function todayLocalDate(): string {
+  return new Date().toLocaleDateString('en-CA')
+}
+
+function plusWeeks(weeks: number): string {
+  const d = new Date()
+  d.setDate(d.getDate() + weeks * 7)
+  return d.toLocaleDateString('en-CA')
+}
+
+export function NewSprintMetadataDialog({
+  open,
+  productId,
+  onOpenChange,
+}: NewSprintMetadataDialogProps) {
+  const [sprintGoal, setSprintGoal] = useState('')
+  const [startDate, setStartDate] = useState(todayLocalDate())
+  const [endDate, setEndDate] = useState(plusWeeks(2))
+  const [error, setError] = useState<string | null>(null)
+  const [dirty, setDirty] = useState(false)
+  const [isPending, startTransition] = useTransition()
+  const formRef = useRef<HTMLFormElement>(null)
+  const setPendingSprintDraft = useUserSettingsStore(
+    (s) => s.setPendingSprintDraft,
+  )
+
+  function reset() {
+    setSprintGoal('')
+    setStartDate(todayLocalDate())
+    setEndDate(plusWeeks(2))
+    setError(null)
+    setDirty(false)
+  }
+
+  const closeGuard = useDirtyCloseGuard(dirty, () => {
+    onOpenChange(false)
+    reset()
+  })
+
+  function handleSubmit(e: React.FormEvent) {
+    e.preventDefault()
+    const goal = sprintGoal.trim()
+    if (!goal) return
+    setError(null)
+    startTransition(async () => {
+      try {
+        await setPendingSprintDraft(productId, {
+          goal,
+          startAt: startDate || undefined,
+          endAt: endDate || undefined,
+          pbiIntent: {},
+          storyOverrides: {},
+        })
+        reset()
+        onOpenChange(false)
+      } catch (err) {
+        const message =
+          err instanceof Error ? err.message : 'Onbekende fout bij opslaan'
+        setError(message)
+        toast.error(message)
+      }
+    })
+  }
+
+  const handleKeyDown = useDialogSubmitShortcut(() =>
+    formRef.current?.requestSubmit(),
+  )
+
+  return (
+    <>
+      <Dialog
+        open={open}
+        onOpenChange={(o) => {
+          if (!o) closeGuard.attemptClose()
+          else onOpenChange(o)
+        }}
+      >
+        <DialogContent
+          showCloseButton={false}
+          onKeyDown={handleKeyDown}
+          className={entityDialogContentClasses}
+          {...debugProps(
+            'new-sprint-metadata-dialog',
+            'NewSprintMetadataDialog',
+            'components/backlog/new-sprint-metadata-dialog.tsx',
+          )}
+        >
+          <div className={entityDialogHeaderClasses}>
+            <DialogTitle className="text-xl font-semibold">
+              Nieuwe sprint
+            </DialogTitle>
+            <p className="text-xs text-muted-foreground mt-1">
+              Geef het sprint-doel en periode op. Je selecteert daarna PBI&apos;s
+              en stories via vinkjes in de backlog.
+            </p>
+          </div>
+
+          <form
+            ref={formRef}
+            id="new-sprint-metadata-form"
+            onSubmit={handleSubmit}
+            onChange={() => setDirty(true)}
+            className="flex-1 overflow-y-auto px-6 py-6 space-y-6"
+          >
+            <div className="space-y-1.5">
+              <label className="text-sm font-medium text-foreground">
+                Sprint Goal <span className="text-error">*</span>
+              </label>
+              <Textarea
+                value={sprintGoal}
+                onChange={(e) => setSprintGoal(e.target.value)}
+                required
+                rows={3}
+                placeholder="Wat wil je aan het einde van deze Sprint bereikt hebben?"
+                autoFocus
+              />
+            </div>
+
+            <div className="grid grid-cols-2 gap-3">
+              <div className="space-y-1.5">
+                <label className="text-sm font-medium text-foreground">
+                  Startdatum
+                </label>
+                <input
+                  type="date"
+                  value={startDate}
+                  onChange={(e) => setStartDate(e.target.value)}
+                  className="w-full rounded-md border border-border bg-surface-container px-3 py-2 text-sm focus:outline-none focus:ring-1 focus:ring-primary"
+                />
+              </div>
+              <div className="space-y-1.5">
+                <label className="text-sm font-medium text-foreground">
+                  Einddatum
+                </label>
+                <input
+                  type="date"
+                  value={endDate}
+                  onChange={(e) => setEndDate(e.target.value)}
+                  className="w-full rounded-md border border-border bg-surface-container px-3 py-2 text-sm focus:outline-none focus:ring-1 focus:ring-primary"
+                />
+              </div>
+            </div>
+
+            {error && (
+              <div className="bg-error-container text-error-container-foreground rounded-lg px-3 py-2 text-sm border-l-4 border-error">
+                {error}
+              </div>
+            )}
+          </form>
+
+          <div className={entityDialogFooterClasses}>
+            <div className="flex justify-end gap-2">
+              <Button
+                type="button"
+                variant="ghost"
+                onClick={closeGuard.attemptClose}
+                disabled={isPending}
+              >
+                Annuleren
+              </Button>
+              <Button
+                type="submit"
+                form="new-sprint-metadata-form"
+                disabled={isPending || !sprintGoal.trim()}
+                data-debug-id="new-sprint-metadata-dialog__submit"
+              >
+                {isPending ? 'Opslaan…' : 'Verder'}
+              </Button>
+            </div>
+          </div>
+        </DialogContent>
+      </Dialog>
+
+      <DirtyCloseGuardDialog guard={closeGuard} />
+    </>
+  )
+}

components/backlog/new-sprint-trigger.tsx

@@ -0,0 +1,46 @@
+'use client'
+
+import { useState } from 'react'
+import { Button } from '@/components/ui/button'
+import { DemoTooltip } from '@/components/shared/demo-tooltip'
+import { useUserSettingsStore } from '@/stores/user-settings/store'
+import { NewSprintMetadataDialog } from './new-sprint-metadata-dialog'
+
+interface NewSprintTriggerProps {
+  productId: string
+  isDemo: boolean
+}
+
+/**
+ * PBI-79 / ST-1337: trigger-knop voor de nieuwe sprint-flow.
+ * Verbergt zichzelf wanneer er al een pendingSprintDraft loopt — dan
+ * staat de SprintDefinitionBanner zelf de afronding te regelen.
+ */
+export function NewSprintTrigger({ productId, isDemo }: NewSprintTriggerProps) {
+  const [open, setOpen] = useState(false)
+  const hasDraft = useUserSettingsStore(
+    (s) => !!s.entities.settings.workflow?.pendingSprintDraft?.[productId],
+  )
+
+  if (hasDraft) return null
+
+  return (
+    <>
+      <DemoTooltip show={isDemo}>
+        <Button
+          size="sm"
+          onClick={() => setOpen(true)}
+          disabled={isDemo}
+          data-debug-id="new-sprint-trigger"
+        >
+          Nieuwe sprint
+        </Button>
+      </DemoTooltip>
+      <NewSprintMetadataDialog
+        open={open}
+        productId={productId}
+        onOpenChange={setOpen}
+      />
+    </>
+  )
+}

components/backlog/pbi-list.tsx

@@ -21,7 +21,7 @@ import {
 } from '@dnd-kit/sortable'
 import { CSS } from '@dnd-kit/utilities'
 import { toast } from 'sonner'
-import { CheckSquare, Square } from 'lucide-react'
+import { CheckSquare, MinusSquare, Square } from 'lucide-react'
 import { Button } from '@/components/ui/button'
 import { Badge } from '@/components/ui/badge'
 import {
@@ -32,7 +32,11 @@ import {
 import { useShallow } from 'zustand/react/shallow'
 import { useUserSettingsStore } from '@/stores/user-settings/store'
 import { useProductWorkspaceStore } from '@/stores/product-workspace/store'
-import { selectVisiblePbis } from '@/stores/product-workspace/selectors'
+import {
+  selectPbiTriState,
+  selectVisiblePbis,
+  type PbiTriState,
+} from '@/stores/product-workspace/selectors'
 import type { BacklogPbi as WorkspacePbi } from '@/stores/product-workspace/types'
 import { deletePbiAction } from '@/actions/pbis'
 import { reorderPbisAction, updatePbiPriorityAction } from '@/actions/stories'
@@ -41,7 +45,6 @@ import { debugProps } from '@/lib/debug'
 import { PbiDialog, type PbiDialogState } from './pbi-dialog'
 import { BacklogCard } from './backlog-card'
 import { EmptyPanel } from './empty-panel'
-import { NewSprintDialog } from '@/components/sprint/new-sprint-dialog'
 import { DemoTooltip } from '@/components/shared/demo-tooltip'
 import { PRIORITY_COLORS } from '@/components/shared/priority-select'
 import { PBI_STATUS_LABELS, PBI_STATUS_COLORS } from '@/components/shared/pbi-status-select'
@@ -77,15 +80,24 @@ interface Pbi {
 interface PbiListProps {
   productId: string
   isDemo: boolean
+  activeSprintId?: string | null
 }
 
 // --- Sortable PBI row ---
+function TriStateIcon({ state }: { state: PbiTriState }) {
+  if (state === 'full')
+    return <CheckSquare size={18} className="text-primary" />
+  if (state === 'partial')
+    return <MinusSquare size={18} className="text-primary" />
+  return <Square size={18} />
+}
+
 function SortablePbiRow({
   pbi,
   isSelected,
   isDemo,
   selectionMode,
-  isChecked,
+  triState,
   onSelect,
   onToggleCheck,
   onEdit,
@@ -95,7 +107,7 @@ function SortablePbiRow({
   isSelected: boolean
   isDemo: boolean
   selectionMode: boolean
-  isChecked: boolean
+  triState: PbiTriState
   onSelect: () => void
   onToggleCheck: () => void
   onEdit: () => void
@@ -119,24 +131,39 @@ function SortablePbiRow({
         title={pbi.title}
         code={pbi.code}
         priority={pbi.priority}
-        isSelected={isChecked}
+        isSelected={isSelected}
         role="button"
         tabIndex={0}
-        aria-pressed={isChecked}
-        onClick={onToggleCheck}
-        onKeyDown={(e: React.KeyboardEvent) => { if (e.key === 'Enter' || e.key === ' ') { e.preventDefault(); onToggleCheck() } }}
+        aria-pressed={isSelected}
+        onClick={onSelect}
+        onKeyDown={(e: React.KeyboardEvent) => {
+          if (e.key === 'Enter' || e.key === ' ') {
+            e.preventDefault()
+            onSelect()
+          }
+        }}
         badge={
           <Badge className={cn('text-xs font-normal', PBI_STATUS_COLORS[pbi.status])}>
             {PBI_STATUS_LABELS[pbi.status]}
           </Badge>
         }
         actions={
-          <div
-            className="inline-flex items-center justify-center min-h-7 min-w-7 text-muted-foreground"
-            aria-hidden="true"
+          <button
+            type="button"
+            onClick={(e) => {
+              e.stopPropagation()
+              onToggleCheck()
+            }}
+            aria-pressed={triState !== 'empty'}
+            aria-label={
+              triState === 'full'
+                ? 'Stories uit sprint halen'
+                : 'Stories aan sprint toevoegen'
+            }
+            className="inline-flex items-center justify-center min-h-7 min-w-7 text-muted-foreground hover:text-foreground rounded transition-colors"
           >
-            {isChecked ? <CheckSquare size={18} className="text-primary" /> : <Square size={18} />}
-          </div>
+            <TriStateIcon state={triState} />
+          </button>
         }
       />
     )
@@ -194,7 +221,7 @@ function SortablePbiRow({
 // --- Main component ---
 // PBI-74 / T-849: leest pbis + actieve selectie uit workspace-store via
 // useShallow-selector. DnD-mutaties via applyOptimisticMutation/rollback/settle.
-export function PbiList({ productId, isDemo }: PbiListProps) {
+export function PbiList({ productId, isDemo, activeSprintId = null }: PbiListProps) {
   // selectVisiblePbis is gesorteerd op priority/sort_order; useShallow
   // voorkomt re-render op ongerelateerde store-mutaties (G2).
   const pbis = useProductWorkspaceStore(useShallow(selectVisiblePbis)) as WorkspacePbi[]
@@ -216,23 +243,49 @@ export function PbiList({ productId, isDemo }: PbiListProps) {
   const [filterPopoverOpen, setFilterPopoverOpen] = useState(false)
   const [dialogState, setDialogState] = useState<PbiDialogState | null>(null)
   const [activeDragId, setActiveDragId] = useState<string | null>(null)
-  const [selectionMode, setSelectionMode] = useState(false)
-  const [selectedIds, setSelectedIds] = useState<Set<string>>(new Set())
-  const [newSprintOpen, setNewSprintOpen] = useState(false)
   const [, startTransition] = useTransition()
 
-  function exitSelection() {
-    setSelectionMode(false)
-    setSelectedIds(new Set())
-  }
+  // PBI-79 / ST-1337+ST-1338: selectionMode is afgeleid uit drie staten:
+  // A′ (pendingSprintDraft) → vinkjes muteren de draft via upsertPbiIntent.
+  // B (activeSprintId zonder draft) → vinkjes muteren de membership-buffer
+  // via toggleStorySprintMembership per child story (bulk).
+  // A (geen sprint, geen draft) → geen vinkjes.
+  const hasDraft = useUserSettingsStore(
+    (s) => !!s.entities.settings.workflow?.pendingSprintDraft?.[productId],
+  )
+  const upsertPbiIntent = useUserSettingsStore((s) => s.upsertPbiIntent)
+  const toggleStorySprintMembership = useProductWorkspaceStore(
+    (s) => s.toggleStorySprintMembership,
+  )
+  const stateBMode = !hasDraft && !!activeSprintId
+  const selectionMode = hasDraft || stateBMode
 
-  function toggleCheck(id: string) {
-    setSelectedIds(prev => {
-      const next = new Set(prev)
-      if (next.has(id)) next.delete(id)
-      else next.add(id)
-      return next
-    })
+  function togglePbiInDraft(id: string, currentState: PbiTriState) {
+    if (hasDraft) {
+      // A′: empty/partial → all; full → none.
+      const nextIntent = currentState === 'full' ? 'none' : 'all'
+      void upsertPbiIntent(productId, id, nextIntent)
+      return
+    }
+    if (stateBMode && activeSprintId) {
+      // State B: bulk-toggle alle child-stories naar/uit de pending buffer.
+      const store = useProductWorkspaceStore.getState()
+      const storyIds = store.relations.storyIdsByPbi[id] ?? []
+      const goingFull = currentState !== 'full'
+      for (const storyId of storyIds) {
+        const story = store.entities.storiesById[storyId]
+        if (!story) continue
+        const blocked = store.sprintMembership.crossSprintBlocks[storyId]
+        if (blocked) continue
+        const inSprint = story.sprint_id === activeSprintId
+        if (goingFull && !inSprint) {
+          toggleStorySprintMembership(storyId, false)
+        }
+        if (!goingFull && inSprint) {
+          toggleStorySprintMembership(storyId, true)
+        }
+      }
+    }
   }
 
   // pbis komen al gesorteerd binnen via selectVisiblePbis (priority + sort_order).
@@ -398,21 +451,6 @@ export function PbiList({ productId, isDemo }: PbiListProps) {
             setSortDir('asc')
           }}
         />
-        <DemoTooltip show={isDemo}>
-          <Button
-            size="sm"
-            variant={selectionMode ? 'default' : 'outline'}
-            className="h-7 text-xs"
-            disabled={isDemo}
-            onClick={() => {
-              if (isDemo) return
-              if (selectionMode) exitSelection()
-              else setSelectionMode(true)
-            }}
-          >
-            {selectionMode ? 'Selecteren stoppen' : "Selecteer PBI's"}
-          </Button>
-        </DemoTooltip>
         <DemoTooltip show={isDemo}>
           <Button
             size="sm"
@@ -445,15 +483,15 @@ export function PbiList({ productId, isDemo }: PbiListProps) {
             >
               <div className="p-3 flex flex-col gap-2" {...debugProps('pbi-list__items')}>
                 {filtered.map(pbi => (
-                  <SortablePbiRow
+                  <SortablePbiRowWithTriState
                     key={pbi.id}
                     pbi={pbi}
                     isSelected={selectedPbiId === pbi.id}
                     isDemo={isDemo}
                     selectionMode={selectionMode}
-                    isChecked={selectedIds.has(pbi.id)}
+                    productId={productId}
                     onSelect={() => useProductWorkspaceStore.getState().setActivePbi(pbi.id)}
-                    onToggleCheck={() => toggleCheck(pbi.id)}
+                    onToggle={togglePbiInDraft}
                     onEdit={() => setDialogState({ mode: 'edit', productId, pbi })}
                     onDelete={() => handleDelete(pbi.id)}
                   />
@@ -474,53 +512,72 @@ export function PbiList({ productId, isDemo }: PbiListProps) {
         )}
       </div>
 
-      {selectionMode && (
-        <div className="border-t border-border bg-surface-container px-4 py-2 flex items-center justify-between gap-2 shrink-0">
-          <span className="text-sm text-foreground">
-            {selectedIds.size} geselecteerd
-          </span>
-          <div className="flex items-center gap-2">
-            <Button
-              size="sm"
-              variant="ghost"
-              className="h-7 text-xs"
-              onClick={exitSelection}
-            >
-              Annuleer
-            </Button>
-            <Button
-              size="sm"
-              className="h-7 text-xs"
-              disabled={selectedIds.size === 0}
-              onClick={() => setNewSprintOpen(true)}
-            >
-              Nieuwe sprint
-            </Button>
-          </div>
-        </div>
-      )}
-
       <PbiDialog
         state={dialogState}
         onClose={() => setDialogState(null)}
         isDemo={isDemo}
       />
-
-      <NewSprintDialog
-        open={newSprintOpen}
-        productId={productId}
-        pbiIds={Array.from(selectedIds)}
-        onOpenChange={(open) => {
-          setNewSprintOpen(open)
-          if (!open) {
-            // Sluit selectie bij geslaagde aanmaak; bij annuleren laat de selectie staan
-          }
-        }}
-        onCreated={() => {
-          setNewSprintOpen(false)
-          exitSelection()
-        }}
-      />
     </div>
   )
 }
+
+// PBI-79 / ST-1337: wrapper rond SortablePbiRow die zijn tri-state uit de
+// workspace-store leest. Subscribed per PBI zodat alleen de relevante rij
+// re-rendert bij pbiIntent/storyOverrides-mutaties.
+function SortablePbiRowWithTriState({
+  pbi,
+  isSelected,
+  isDemo,
+  selectionMode,
+  productId,
+  onSelect,
+  onToggle,
+  onEdit,
+  onDelete,
+}: {
+  pbi: Pbi
+  isSelected: boolean
+  isDemo: boolean
+  selectionMode: boolean
+  productId: string
+  onSelect: () => void
+  onToggle: (id: string, currentState: PbiTriState) => void
+  onEdit: () => void
+  onDelete: () => void
+}) {
+  // Tri-state uit pendingSprintDraft (state A′) of pbiSummary (state B).
+  // Wanneer geen draft: leid af van pbiSummary; wanneer wel: uit pbiIntent.
+  const triState = useUserSettingsStore((s) => {
+    const draft = s.entities.settings.workflow?.pendingSprintDraft?.[productId]
+    if (draft) {
+      const intent = draft.pbiIntent[pbi.id] ?? 'none'
+      const override = draft.storyOverrides[pbi.id]
+      if (intent === 'all') {
+        if (override?.remove.length) return 'partial'
+        return 'full'
+      }
+      if (override?.add.length) return 'partial'
+      return 'empty'
+    }
+    return null
+  })
+  const summaryTriState = useProductWorkspaceStore((s) =>
+    selectPbiTriState(s, pbi.id),
+  )
+  const effectiveTriState: PbiTriState =
+    triState ?? (selectionMode ? summaryTriState : 'empty')
+
+  return (
+    <SortablePbiRow
+      pbi={pbi}
+      isSelected={isSelected}
+      isDemo={isDemo}
+      selectionMode={selectionMode}
+      triState={effectiveTriState}
+      onSelect={onSelect}
+      onToggleCheck={() => onToggle(pbi.id, effectiveTriState)}
+      onEdit={onEdit}
+      onDelete={onDelete}
+    />
+  )
+}

components/backlog/save-sprint-button.tsx

@@ -0,0 +1,89 @@
+'use client'
+
+import { useTransition } from 'react'
+import { useRouter } from 'next/navigation'
+import { toast } from 'sonner'
+import { Button } from '@/components/ui/button'
+import { useProductWorkspaceStore } from '@/stores/product-workspace/store'
+import {
+  selectIsDirty,
+  selectPendingCount,
+} from '@/stores/product-workspace/selectors'
+import { commitSprintMembershipAction } from '@/actions/sprints'
+
+interface SaveSprintButtonProps {
+  activeSprintId: string
+}
+
+/**
+ * PBI-79 / ST-1338 / T-940: 'Sprint opslaan'-knop voor state B.
+ * Altijd zichtbaar zolang er een actieve sprint is. Disabled bij clean,
+ * enabled met teller bij dirty. Commit gebeurt via
+ * commitSprintMembershipAction; client patcht gericht via
+ * applyMembershipCommitResult. Geen router.refresh.
+ */
+export function SaveSprintButton({ activeSprintId }: SaveSprintButtonProps) {
+  const router = useRouter()
+  const isDirty = useProductWorkspaceStore(selectIsDirty)
+  const count = useProductWorkspaceStore(selectPendingCount)
+  const adds = useProductWorkspaceStore((s) => s.sprintMembership.pending.adds)
+  const removes = useProductWorkspaceStore(
+    (s) => s.sprintMembership.pending.removes,
+  )
+  const applyMembershipCommitResult = useProductWorkspaceStore(
+    (s) => s.applyMembershipCommitResult,
+  )
+  const [isPending, startTransition] = useTransition()
+
+  function handleSave() {
+    startTransition(async () => {
+      const result = await commitSprintMembershipAction({
+        activeSprintId,
+        adds: [...adds],
+        removes: [...removes],
+      })
+      if ('error' in result) {
+        toast.error(result.error)
+        return
+      }
+      applyMembershipCommitResult({
+        activeSprintId,
+        addedStoryIds: adds.filter((id) =>
+          result.affectedStoryIds.includes(id),
+        ),
+        removedStoryIds: removes.filter((id) =>
+          result.affectedStoryIds.includes(id),
+        ),
+      })
+      const skipped =
+        result.conflicts.notEligible.length +
+        result.conflicts.alreadyRemoved.length
+      if (skipped > 0) {
+        toast.warning(
+          `${skipped} wijziging${skipped === 1 ? '' : 'en'} overgeslagen — story al in andere sprint of inmiddels verwijderd.`,
+        )
+      } else {
+        toast.success('Sprint opgeslagen')
+      }
+      // Gericht patchen voldoende voor lokale UI; refresh haalt server-side
+      // counts opnieuw op zodat tri-state in volgende renders klopt.
+      router.refresh()
+    })
+  }
+
+  return (
+    <Button
+      type="button"
+      size="sm"
+      onClick={handleSave}
+      disabled={!isDirty || isPending}
+      data-debug-id="save-sprint-button"
+    >
+      {isPending
+        ? 'Opslaan…'
+        : isDirty
+        ? `Sprint opslaan (${count})`
+        : 'Sprint opslaan'}
+    </Button>
+  )
+}

components/backlog/sprint-definition-banner.tsx

@@ -0,0 +1,202 @@
+'use client'
+
+import { useMemo, useState, useTransition } from 'react'
+import { useRouter } from 'next/navigation'
+import { toast } from 'sonner'
+import { Button } from '@/components/ui/button'
+import {
+  AlertDialog,
+  AlertDialogAction,
+  AlertDialogCancel,
+  AlertDialogContent,
+  AlertDialogDescription,
+  AlertDialogFooter,
+  AlertDialogHeader,
+  AlertDialogTitle,
+} from '@/components/ui/alert-dialog'
+import { useUserSettingsStore } from '@/stores/user-settings/store'
+import { useProductWorkspaceStore } from '@/stores/product-workspace/store'
+import type { PendingSprintDraft } from '@/lib/user-settings'
+import { createSprintWithSelectionAction } from '@/actions/sprints'
+import { debugProps } from '@/lib/debug'
+
+interface SprintDefinitionBannerProps {
+  productId: string
+  draft: PendingSprintDraft
+}
+
+type DraftCounts = {
+  pbiCount: number
+  storyCount: number
+  hasUnknownTotal: boolean
+}
+
+function computeCounts(
+  draft: PendingSprintDraft,
+  pbiSummary: Record<
+    string,
+    { totalStoryCount: number; inActiveSprintStoryCount: number }
+  >,
+): DraftCounts {
+  let pbiCount = 0
+  let storyCount = 0
+  let hasUnknownTotal = false
+
+  const seenPbis = new Set<string>()
+
+  for (const [pbiId, intent] of Object.entries(draft.pbiIntent)) {
+    if (intent === 'all') {
+      seenPbis.add(pbiId)
+      const summary = pbiSummary[pbiId]
+      const override = draft.storyOverrides[pbiId]
+      if (!summary) {
+        hasUnknownTotal = true
+        continue
+      }
+      const removed = override?.remove.length ?? 0
+      storyCount += Math.max(0, summary.totalStoryCount - removed)
+    }
+  }
+
+  for (const [pbiId, override] of Object.entries(draft.storyOverrides)) {
+    if (override.add.length === 0) continue
+    seenPbis.add(pbiId)
+    storyCount += override.add.length
+  }
+
+  pbiCount = seenPbis.size
+  return { pbiCount, storyCount, hasUnknownTotal }
+}
+
+export function SprintDefinitionBanner({
+  productId,
+  draft,
+}: SprintDefinitionBannerProps) {
+  const clearPendingSprintDraft = useUserSettingsStore(
+    (s) => s.clearPendingSprintDraft,
+  )
+  const pbiSummary = useProductWorkspaceStore((s) => s.sprintMembership.pbiSummary)
+  const router = useRouter()
+  const [isPending, startTransition] = useTransition()
+  const [confirmCancel, setConfirmCancel] = useState(false)
+
+  const counts = useMemo(
+    () => computeCounts(draft, pbiSummary),
+    [draft, pbiSummary],
+  )
+
+  function handleCancel() {
+    setConfirmCancel(true)
+  }
+
+  function confirmCancelAction() {
+    setConfirmCancel(false)
+    startTransition(async () => {
+      try {
+        await clearPendingSprintDraft(productId)
+      } catch (err) {
+        const message =
+          err instanceof Error ? err.message : 'Annuleren mislukt'
+        toast.error(message)
+      }
+    })
+  }
+
+  function handleCreate() {
+    startTransition(async () => {
+      const result = await createSprintWithSelectionAction({
+        productId,
+        metadata: {
+          goal: draft.goal,
+          startAt: draft.startAt,
+          endAt: draft.endAt,
+        },
+        pbiIntent: draft.pbiIntent,
+        storyOverrides: draft.storyOverrides,
+      })
+      if ('error' in result) {
+        toast.error(result.error)
+        return
+      }
+      const { conflicts } = result
+      if (conflicts.notEligible.length > 0) {
+        toast.warning(
+          `${conflicts.notEligible.length} stor${
+            conflicts.notEligible.length === 1 ? 'y is' : 'ies zijn'
+          } overgeslagen (al in een andere sprint of afgerond).`,
+        )
+      } else {
+        toast.success('Sprint aangemaakt')
+      }
+      router.refresh()
+    })
+  }
+
+  const storyLabel = counts.hasUnknownTotal
+    ? `${counts.storyCount}+`
+    : counts.storyCount
+  const pbiSuffix = counts.pbiCount === 1 ? '' : "'s"
+
+  return (
+    <div
+      className="sticky top-0 z-30 bg-tertiary-container text-tertiary-container-foreground border-b border-tertiary px-4 py-2.5 flex items-center gap-4"
+      {...debugProps('sprint-definition-banner')}
+    >
+      <div className="flex-1 min-w-0">
+        <div className="flex items-baseline gap-2">
+          <span className="text-sm font-medium shrink-0">
+            Sprint definiëren —
+          </span>
+          <span className="text-sm truncate" title={draft.goal}>
+            {draft.goal}
+          </span>
+        </div>
+        <div className="text-xs opacity-80 mt-0.5">
+          {counts.pbiCount} PBI{pbiSuffix} · {storyLabel} stor
+          {counts.storyCount === 1 ? 'y' : 'ies'} geselecteerd
+        </div>
+      </div>
+      <div className="flex items-center gap-2 shrink-0">
+        <Button
+          type="button"
+          variant="ghost"
+          onClick={handleCancel}
+          disabled={isPending}
+          data-debug-id="sprint-definition-banner__cancel"
+        >
+          Annuleren
+        </Button>
+        <Button
+          type="button"
+          onClick={handleCreate}
+          disabled={isPending || counts.pbiCount === 0}
+          data-debug-id="sprint-definition-banner__create"
+        >
+          Sprint aanmaken
+        </Button>
+      </div>
+      <AlertDialog open={confirmCancel} onOpenChange={setConfirmCancel}>
+        <AlertDialogContent size="sm">
+          <AlertDialogHeader>
+            <AlertDialogTitle>Sprint-definitie annuleren?</AlertDialogTitle>
+            <AlertDialogDescription>
+              Je conceptselectie gaat verloren. Het sprint-doel en de
+              gemarkeerde PBI/stories worden verwijderd.
+            </AlertDialogDescription>
+          </AlertDialogHeader>
+          <AlertDialogFooter>
+            <AlertDialogCancel onClick={() => setConfirmCancel(false)}>
+              Doorgaan
+            </AlertDialogCancel>
+            <AlertDialogAction
+              variant="destructive"
+              onClick={confirmCancelAction}
+            >
+              Ja, annuleren
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
+    </div>
+  )
+}

components/backlog/sprint-draft-banner.tsx

@@ -0,0 +1,22 @@
+'use client'
+
+import { useUserSettingsStore } from '@/stores/user-settings/store'
+import { SprintDefinitionBanner } from './sprint-definition-banner'
+
+interface SprintDraftBannerProps {
+  productId: string
+}
+
+/**
+ * PBI-79 / ST-1337: client-wrapper die de SprintDefinitionBanner alleen rendert
+ * als er een pendingSprintDraft voor dit product staat. Hydratatie loopt via
+ * UserSettingsBridge — dit component subscribt op die store en is daarmee
+ * automatisch reactief op draft-mutaties (set/clear).
+ */
+export function SprintDraftBanner({ productId }: SprintDraftBannerProps) {
+  const draft = useUserSettingsStore(
+    (s) => s.entities.settings.workflow?.pendingSprintDraft?.[productId],
+  )
+  if (!draft) return null
+  return <SprintDefinitionBanner productId={productId} draft={draft} />
+}

components/backlog/sprint-draft-leave-guard.tsx

@@ -0,0 +1,37 @@
+'use client'
+
+import { useEffect } from 'react'
+import { useUserSettingsStore } from '@/stores/user-settings/store'
+
+interface SprintDraftLeaveGuardProps {
+  productId: string
+}
+
+/**
+ * PBI-79: window.beforeunload-waarschuwing zolang er een pendingSprintDraft
+ * loopt voor dit product. De draft is session-only en gaat verloren bij
+ * refresh/close — deze guard zorgt dat de gebruiker dat eerst bevestigt.
+ * Voor in-app route-changes (klikken op een andere product) doet Next.js
+ * geen onbeforeunload; daar vangen we het op via de banner-Annuleren-flow.
+ */
+export function SprintDraftLeaveGuard({
+  productId,
+}: SprintDraftLeaveGuardProps) {
+  const hasDraft = useUserSettingsStore(
+    (s) => !!s.entities.settings.workflow?.pendingSprintDraft?.[productId],
+  )
+
+  useEffect(() => {
+    if (!hasDraft) return
+    function handler(e: BeforeUnloadEvent) {
+      e.preventDefault()
+      // Moderne browsers tonen een eigen vertaalde tekst; returnValue is
+      // alleen nodig voor legacy compat.
+      e.returnValue = ''
+    }
+    window.addEventListener('beforeunload', handler)
+    return () => window.removeEventListener('beforeunload', handler)
+  }, [hasDraft])
+
+  return null
+}

components/backlog/sprint-edit-dialog.tsx

@@ -0,0 +1,217 @@
+'use client'
+
+import { useRef, useState, useTransition } from 'react'
+import { useRouter } from 'next/navigation'
+import Link from 'next/link'
+import { toast } from 'sonner'
+import { Button } from '@/components/ui/button'
+import { Textarea } from '@/components/ui/textarea'
+import { Dialog, DialogContent, DialogTitle } from '@/components/ui/dialog'
+import {
+  useDirtyCloseGuard,
+  DirtyCloseGuardDialog,
+} from '@/components/shared/use-dirty-close-guard'
+import { useDialogSubmitShortcut } from '@/components/shared/use-dialog-submit-shortcut'
+import {
+  entityDialogContentClasses,
+  entityDialogFooterClasses,
+  entityDialogHeaderClasses,
+} from '@/components/shared/entity-dialog-layout'
+import { updateSprintAction } from '@/actions/sprints'
+import { debugProps } from '@/lib/debug'
+
+interface SprintEditDialogProps {
+  open: boolean
+  productId: string
+  sprint: {
+    id: string
+    code: string
+    sprint_goal: string
+    start_date?: string | null
+    end_date?: string | null
+  }
+  onOpenChange: (open: boolean) => void
+}
+
+function toDateInput(value: string | null | undefined): string {
+  if (!value) return ''
+  // Accept ISO datetime or YYYY-MM-DD; output YYYY-MM-DD.
+  const d = new Date(value)
+  if (Number.isNaN(d.getTime())) return ''
+  return d.toLocaleDateString('en-CA')
+}
+
+export function SprintEditDialog({
+  open,
+  productId,
+  sprint,
+  onOpenChange,
+}: SprintEditDialogProps) {
+  const [goal, setGoal] = useState(sprint.sprint_goal)
+  const [startDate, setStartDate] = useState(toDateInput(sprint.start_date))
+  const [endDate, setEndDate] = useState(toDateInput(sprint.end_date))
+  const [error, setError] = useState<string | null>(null)
+  const [dirty, setDirty] = useState(false)
+  const [isPending, startTransition] = useTransition()
+  const formRef = useRef<HTMLFormElement>(null)
+  const router = useRouter()
+
+  function reset() {
+    setGoal(sprint.sprint_goal)
+    setStartDate(toDateInput(sprint.start_date))
+    setEndDate(toDateInput(sprint.end_date))
+    setError(null)
+    setDirty(false)
+  }
+
+  const closeGuard = useDirtyCloseGuard(dirty, () => {
+    onOpenChange(false)
+    reset()
+  })
+
+  function handleSubmit(e: React.FormEvent) {
+    e.preventDefault()
+    const trimmed = goal.trim()
+    if (!trimmed) return
+    setError(null)
+    startTransition(async () => {
+      const result = await updateSprintAction({
+        sprintId: sprint.id,
+        fields: {
+          goal: trimmed,
+          startAt: startDate || null,
+          endAt: endDate || null,
+        },
+      })
+      if ('error' in result) {
+        setError(result.error)
+        toast.error(result.error)
+        return
+      }
+      toast.success('Sprint bijgewerkt')
+      onOpenChange(false)
+      router.refresh()
+    })
+  }
+
+  const handleKeyDown = useDialogSubmitShortcut(() =>
+    formRef.current?.requestSubmit(),
+  )
+
+  return (
+    <>
+      <Dialog
+        open={open}
+        onOpenChange={(o) => {
+          if (!o) closeGuard.attemptClose()
+          else onOpenChange(o)
+        }}
+      >
+        <DialogContent
+          showCloseButton={false}
+          onKeyDown={handleKeyDown}
+          className={entityDialogContentClasses}
+          {...debugProps(
+            'sprint-edit-dialog',
+            'SprintEditDialog',
+            'components/backlog/sprint-edit-dialog.tsx',
+          )}
+        >
+          <div className={entityDialogHeaderClasses}>
+            <DialogTitle className="text-xl font-semibold">
+              Sprint {sprint.code} bewerken
+            </DialogTitle>
+            <p className="text-xs text-muted-foreground mt-1">
+              Wijzig sprint-doel en datums. Voor afronding (per-story DONE/OPEN
+              beslissing) ga naar de sprint-pagina.
+            </p>
+          </div>
+
+          <form
+            ref={formRef}
+            id="sprint-edit-form"
+            onSubmit={handleSubmit}
+            onChange={() => setDirty(true)}
+            className="flex-1 overflow-y-auto px-6 py-6 space-y-6"
+          >
+            <div className="space-y-1.5">
+              <label className="text-sm font-medium text-foreground">
+                Sprint Goal <span className="text-error">*</span>
+              </label>
+              <Textarea
+                value={goal}
+                onChange={(e) => setGoal(e.target.value)}
+                required
+                rows={3}
+                autoFocus
+              />
+            </div>
+
+            <div className="grid grid-cols-2 gap-3">
+              <div className="space-y-1.5">
+                <label className="text-sm font-medium text-foreground">
+                  Startdatum
+                </label>
+                <input
+                  type="date"
+                  value={startDate}
+                  onChange={(e) => setStartDate(e.target.value)}
+                  className="w-full rounded-md border border-border bg-surface-container px-3 py-2 text-sm focus:outline-none focus:ring-1 focus:ring-primary"
+                />
+              </div>
+              <div className="space-y-1.5">
+                <label className="text-sm font-medium text-foreground">
+                  Einddatum
+                </label>
+                <input
+                  type="date"
+                  value={endDate}
+                  onChange={(e) => setEndDate(e.target.value)}
+                  className="w-full rounded-md border border-border bg-surface-container px-3 py-2 text-sm focus:outline-none focus:ring-1 focus:ring-primary"
+                />
+              </div>
+            </div>
+
+            <div className="pt-2 border-t border-border">
+              <Link
+                href={`/products/${productId}/sprint/${sprint.id}`}
+                className="text-sm text-primary hover:underline"
+              >
+                Sprint afronden… →
+              </Link>
+            </div>
+
+            {error && (
+              <div className="bg-error-container text-error-container-foreground rounded-lg px-3 py-2 text-sm border-l-4 border-error">
+                {error}
+              </div>
+            )}
+          </form>
+
+          <div className={entityDialogFooterClasses}>
+            <div className="flex justify-end gap-2">
+              <Button
+                type="button"
+                variant="ghost"
+                onClick={closeGuard.attemptClose}
+                disabled={isPending}
+              >
+                Annuleren
+              </Button>
+              <Button
+                type="submit"
+                form="sprint-edit-form"
+                disabled={isPending || !goal.trim()}
+                data-debug-id="sprint-edit-dialog__submit"
+              >
+                {isPending ? 'Opslaan…' : 'Opslaan'}
+              </Button>
+            </div>
+          </div>
+        </DialogContent>
+      </Dialog>
+
+      <DirtyCloseGuardDialog guard={closeGuard} />
+    </>
+  )
+}

components/backlog/story-panel.tsx

@@ -21,6 +21,13 @@ import {
 } from '@dnd-kit/sortable'
 import { CSS } from '@dnd-kit/utilities'
 import { toast } from 'sonner'
+import { CheckSquare, Square } from 'lucide-react'
+import {
+  Tooltip,
+  TooltipContent,
+  TooltipProvider,
+  TooltipTrigger,
+} from '@/components/ui/tooltip'
 import { Button } from '@/components/ui/button'
 import { Badge } from '@/components/ui/badge'
 import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select'
@@ -28,7 +35,10 @@ import { PanelNavBar } from '@/components/shared/panel-nav-bar'
 import { useShallow } from 'zustand/react/shallow'
 import { useUserSettingsStore } from '@/stores/user-settings/store'
 import { useProductWorkspaceStore } from '@/stores/product-workspace/store'
-import { selectStoriesForActivePbi } from '@/stores/product-workspace/selectors'
+import {
+  selectStoriesForActivePbi,
+  selectStoryIsBlocked,
+} from '@/stores/product-workspace/selectors'
 import type { BacklogStory as WorkspaceStory } from '@/stores/product-workspace/types'
 import { reorderStoriesAction } from '@/actions/stories'
 import { StoryDialog, type StoryDialogState } from './story-dialog'
@@ -67,17 +77,24 @@ export interface Story {
 interface StoryPanelProps {
   productId: string
   isDemo: boolean
+  activeSprintId?: string | null
 }
 
 // --- Sortable story block ---
 function SortableStoryBlock({
   story,
   isSelected,
+  cherrypick,
   onSelect,
   onEdit,
 }: {
   story: Story
   isSelected: boolean
+  cherrypick: {
+    checked: boolean
+    blocked: { sprintName: string } | null
+    onToggle: () => void
+  } | null
   onSelect: () => void
   onEdit: () => void
 }) {
@@ -109,25 +126,79 @@ function SortableStoryBlock({
         </Badge>
       }
       actions={
-        <button
-          onClick={(e) => { e.stopPropagation(); onEdit() }}
-          className="inline-flex items-center justify-center min-h-7 min-w-7 text-muted-foreground hover:text-foreground rounded transition-colors"
-          aria-label="Story bewerken"
-        >
-          <svg className="size-3.5" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
-            <path d="M11 4H4a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2v-7" />
-            <path d="M18.5 2.5a2.121 2.121 0 0 1 3 3L12 15l-4 1 1-4 9.5-9.5z" />
-          </svg>
-        </button>
+        <div className="flex items-center gap-1">
+          {cherrypick && <StoryCherrypickButton {...cherrypick} />}
+          <button
+            onClick={(e) => { e.stopPropagation(); onEdit() }}
+            className="inline-flex items-center justify-center min-h-7 min-w-7 text-muted-foreground hover:text-foreground rounded transition-colors"
+            aria-label="Story bewerken"
+          >
+            <svg className="size-3.5" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+              <path d="M11 4H4a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2v-7" />
+              <path d="M18.5 2.5a2.121 2.121 0 0 1 3 3L12 15l-4 1 1-4 9.5-9.5z" />
+            </svg>
+          </button>
+        </div>
       }
     />
   )
 }
 
+function StoryCherrypickButton({
+  checked,
+  blocked,
+  onToggle,
+}: {
+  checked: boolean
+  blocked: { sprintName: string } | null
+  onToggle: () => void
+}) {
+  const icon = checked ? (
+    <CheckSquare size={16} className="text-primary" />
+  ) : (
+    <Square size={16} />
+  )
+  if (blocked) {
+    return (
+      <TooltipProvider>
+        <Tooltip>
+          <TooltipTrigger
+            data-disabled="true"
+            aria-disabled="true"
+            onClick={(e) => e.stopPropagation()}
+            className="inline-flex items-center justify-center min-h-7 min-w-7 rounded opacity-40 cursor-not-allowed text-muted-foreground"
+          >
+            {icon}
+          </TooltipTrigger>
+          <TooltipContent>Zit in sprint {blocked.sprintName}</TooltipContent>
+        </Tooltip>
+      </TooltipProvider>
+    )
+  }
+  return (
+    <button
+      onClick={(e) => {
+        e.stopPropagation()
+        onToggle()
+      }}
+      aria-pressed={checked}
+      aria-label={
+        checked ? 'Story uit sprint halen' : 'Story aan sprint toevoegen'
+      }
+      className={cn(
+        'inline-flex items-center justify-center min-h-7 min-w-7 rounded transition-colors',
+        'text-muted-foreground hover:text-foreground',
+      )}
+    >
+      {icon}
+    </button>
+  )
+}
+
 // --- Main component ---
 // PBI-74 / T-850: leest stories voor active PBI via selectStoriesForActivePbi
 // (useShallow). DnD via applyOptimisticMutation('story-order').
-export function StoryPanel({ productId, isDemo }: StoryPanelProps) {
+export function StoryPanel({ productId, isDemo, activeSprintId = null }: StoryPanelProps) {
   const selectedPbiId = useProductWorkspaceStore((s) => s.context.activePbiId)
   const selectedStoryId = useProductWorkspaceStore((s) => s.context.activeStoryId)
   const rawStories = useProductWorkspaceStore(useShallow(selectStoriesForActivePbi)) as WorkspaceStory[]
@@ -300,9 +371,11 @@ export function StoryPanel({ productId, isDemo }: StoryPanelProps) {
             <SortableContext items={filtered.map(s => s.id)} strategy={rectSortingStrategy}>
               <div className="grid grid-cols-3 gap-2">
                 {filtered.map(story => (
-                  <SortableStoryBlock
+                  <StoryBlockWithCherrypick
                     key={story.id}
                     story={story}
+                    productId={productId}
+                    activeSprintId={activeSprintId}
                     isSelected={selectedStoryId === story.id}
                     onSelect={() => useProductWorkspaceStore.getState().setActiveStory(story.id)}
                     onEdit={() => setStoryDialogState({ mode: 'edit', story, productId })}
@@ -332,3 +405,96 @@ export function StoryPanel({ productId, isDemo }: StoryPanelProps) {
     </div>
   )
 }
+
+// PBI-79 / ST-1337: wrapper rond SortableStoryBlock met cherrypick-handling.
+// Subscribed per story zodat enkel de relevante rij re-rendert bij draft- of
+// crossSprintBlocks-mutaties.
+function StoryBlockWithCherrypick({
+  story,
+  productId,
+  activeSprintId,
+  isSelected,
+  onSelect,
+  onEdit,
+}: {
+  story: Story
+  productId: string
+  activeSprintId: string | null
+  isSelected: boolean
+  onSelect: () => void
+  onEdit: () => void
+}) {
+  const draft = useUserSettingsStore(
+    (s) => s.entities.settings.workflow?.pendingSprintDraft?.[productId],
+  )
+  const upsertStoryOverride = useUserSettingsStore((s) => s.upsertStoryOverride)
+  const toggleStorySprintMembership = useProductWorkspaceStore(
+    (s) => s.toggleStorySprintMembership,
+  )
+  const pending = useProductWorkspaceStore((s) => s.sprintMembership.pending)
+  const blocked = useProductWorkspaceStore((s) =>
+    selectStoryIsBlocked(s, story.id),
+  )
+
+  let cherrypick: {
+    checked: boolean
+    blocked: { sprintName: string } | null
+    onToggle: () => void
+  } | null = null
+
+  if (draft) {
+    // State A′: muteer draft via per-PBI overrides.
+    const intent = draft.pbiIntent[story.pbi_id] ?? 'none'
+    const override = draft.storyOverrides[story.pbi_id] ?? {
+      add: [],
+      remove: [],
+    }
+    const checked =
+      (intent === 'all' && !override.remove.includes(story.id)) ||
+      override.add.includes(story.id)
+    cherrypick = {
+      checked,
+      blocked: blocked ? { sprintName: blocked.sprintName } : null,
+      onToggle: () => {
+        if (intent === 'all') {
+          void upsertStoryOverride(
+            productId,
+            story.pbi_id,
+            story.id,
+            checked ? 'remove' : 'clear',
+          )
+        } else {
+          void upsertStoryOverride(
+            productId,
+            story.pbi_id,
+            story.id,
+            checked ? 'clear' : 'add',
+          )
+        }
+      },
+    }
+  } else if (activeSprintId) {
+    // State B: muteer pending buffer via toggleStorySprintMembership.
+    const inSprintDb = story.sprint_id === activeSprintId
+    const inAdds = pending.adds.includes(story.id)
+    const inRemoves = pending.removes.includes(story.id)
+    const checked = inAdds || (inSprintDb && !inRemoves)
+    cherrypick = {
+      checked,
+      blocked: blocked ? { sprintName: blocked.sprintName } : null,
+      onToggle: () => {
+        toggleStorySprintMembership(story.id, inSprintDb)
+      },
+    }
+  }
+
+  return (
+    <SortableStoryBlock
+      story={story}
+      isSelected={isSelected}
+      cherrypick={cherrypick}
+      onSelect={onSelect}
+      onEdit={onEdit}
+    />
+  )
+}

components/shared/sprint-switcher.tsx

@@ -13,7 +13,12 @@ import {
   DropdownMenuTrigger,
 } from '@/components/ui/dropdown-menu'
 import { cn } from '@/lib/utils'
-import { setActiveSprintAction } from '@/actions/active-sprint'
+import {
+  clearActiveSprintAction,
+  switchActiveSprintAction,
+} from '@/actions/active-sprint'
+import { useProductWorkspaceStore } from '@/stores/product-workspace/store'
+import { useUserSettingsStore } from '@/stores/user-settings/store'
 import type { SprintStatusApi } from '@/lib/task-status'
 import { debugProps } from '@/lib/debug'
 
@@ -45,6 +50,13 @@ export function SprintSwitcher({
   const [showClosed, setShowClosed] = useState(false)
   const buildingSet = new Set(buildingSprintIds)
 
+  // PBI-79: zolang er een sprint-draft loopt tonen we 'Concept — [goal]'
+  // bovenaan de dropdown. De draft staat alleen in deze session-store; bij
+  // page-refresh/leave is hij weg.
+  const draftGoal = useUserSettingsStore(
+    (s) => s.entities.settings.workflow?.pendingSprintDraft?.[productId]?.goal ?? null,
+  )
+
   const visibleSprints = sprints.filter(s => {
     if (showClosed) return true
     if (s.id === activeSprint?.id) return true
@@ -54,13 +66,43 @@ export function SprintSwitcher({
   function handleSwitchSprint(sprintId: string) {
     if (sprintId === activeSprint?.id) return
     startTransition(async () => {
-      const result = await setActiveSprintAction(productId, sprintId)
+      const result = await switchActiveSprintAction(productId, sprintId)
+      if ('error' in result) {
+        toast.error(
+          typeof result.error === 'string' ? result.error : 'Wisselen mislukt',
+        )
+        return
+      }
+      // Synchroniseer de client-side workspace-store met de auto-select die
+      // server-side is bepaald — voorkomt korte flash van vorige selectie
+      // voordat router.refresh de SSR-render binnenhaalt.
+      const store = useProductWorkspaceStore.getState()
+      if (result.pbiId) {
+        store.setActivePbi(result.pbiId)
+        if (result.storyId) {
+          store.setActiveStory(result.storyId)
+        }
+      } else {
+        store.setActivePbi(null)
+      }
+      if (pathname.includes('/sprint')) {
+        router.push(`/products/${productId}/sprint/${sprintId}`)
+      } else {
+        router.refresh()
+      }
+    })
+  }
+
+  function handleClearActiveSprint() {
+    if (!activeSprint) return
+    startTransition(async () => {
+      const result = await clearActiveSprintAction(productId)
       if (result?.error) {
         toast.error(typeof result.error === 'string' ? result.error : 'Wisselen mislukt')
         return
       }
       if (pathname.includes('/sprint')) {
-        router.push(`/products/${productId}/sprint/${sprintId}`)
+        router.push(`/products/${productId}`)
       } else {
         router.refresh()
       }
@@ -127,6 +169,30 @@ export function SprintSwitcher({
           Toon afgeronde sprints
         </button>
         <DropdownMenuSeparator />
+        {draftGoal && (
+          <>
+            <DropdownMenuItem
+              disabled
+              className="italic text-tertiary opacity-90 cursor-default"
+              data-debug-id="sprint-switcher__concept"
+            >
+              <span className="shrink-0">⚙ Concept —</span>
+              <span className="truncate">{draftGoal}</span>
+            </DropdownMenuItem>
+            <DropdownMenuSeparator />
+          </>
+        )}
+        <DropdownMenuItem
+          onClick={handleClearActiveSprint}
+          disabled={!activeSprint || isPending}
+          className={cn(
+            'italic text-muted-foreground',
+            !activeSprint && 'opacity-50 cursor-not-allowed',
+          )}
+        >
+          — Geen actieve sprint —
+        </DropdownMenuItem>
+        <DropdownMenuSeparator />
         {visibleSprints.length === 0 ? (
           <div className="px-2 py-2 text-sm text-muted-foreground/70 italic">
             Geen open sprints

docs/INDEX.md

@@ -45,6 +45,7 @@ Auto-generated on 2026-05-11 from front-matter and headings.
 | [M11 — Claude vraagt, gebruiker antwoordt](./plans/M11-claude-questions.md) | active | 2026-05-03 |
 | [M12 — Idea entity + Grill/Plan Claude jobs](./plans/M12-ideas.md) | planned | — |
 | [M9 — Actief Product Backlog](./plans/M9-active-product-backlog.md) | active | 2026-05-03 |
+| [PBI-79: Product Backlog workflow — sprint-membership via vinkjes](./plans/PBI-79-backlog-sprint-workflow.md) | — | — |
 | [Queue-loop verplaatsen van Claude naar runner](./plans/queue-loop-extraction.md) | — | — |
 | [Advies - SprintRun, PR en worktree lifecycle als state machines](./plans/sprint-pr-worktree-state-machines.md) | draft | 2026-05-06 |
 | [ST-1109 — PBI krijgt een status (Ready / Blocked / Done)](./plans/ST-1109-pbi-status.md) | active | 2026-05-03 |

docs/plans/PBI-79-backlog-sprint-workflow.md

@@ -0,0 +1,649 @@
+# PBI-79: Product Backlog workflow — sprint-membership via vinkjes
+
+> **MCP:** PBI-79 (`cmp13vrxd0001m017ta9aflg9`) in Scrum4Me product (`cmohrysyj0000rd17clnjy4tc`).
+>
+> **Review verwerkt:** Dit plan is een herziene versie na de review in [`product-backlog-workflow-plan-review.md`](product-backlog-workflow-plan-review.md). De vier P1-bevindingen zijn allemaal geadresseerd, evenals de vijf P2-punten. Zie de sectie *"Reactie op review"* onderaan voor de mapping.
+
+---
+
+## Implementatie-stand & scope-aanpassingen (post-testing)
+
+> Deze sectie documenteert wat er sinds de eerste implementatie-pass is bijgewerkt op basis van gebruikerstests + nieuwe inzichten. De rest van het plan beneden geldt **behalve waar dit kopje dat overrulet**.
+
+### Gerealiseerde commits (in volgorde)
+
+| # | Commit | Story | Inhoud |
+|---|---|---|---|
+| 1 | 2af6f24 | ST-1333 | Active-sprint null-contract + clearActiveSprintAction |
+| 2 | 56c55e1 | ST-1334 | pendingSprintDraft slot (compacte intent-shape) |
+| 3 | b4a515e | ST-1343 | `lib/sprint-conflicts.ts` eligibility helpers |
+| 4 | e89fb71 | ST-1335 | Gescoped endpoints (`sprint-membership-summary`, `cross-sprint-blocks`) |
+| 5 | 89c2356 | ST-1336 | `sprintMembership`-slice + selectors in product-workspace-store |
+| 6 | 947d970 | ST-1337 | State A′ UI (metadata-dialog + sticky banner + PbiList ombouw) |
+| 7 | d21011c | ST-1339 | `createSprintWithSelectionAction` + banner wire-up |
+| 8 | 4c6e999 | ST-1340 | `commitSprintMembershipAction` + gerichte client-store patches |
+| 9 | 117616f | ST-1338 | State B vinkjes-UI + "Sprint opslaan"-knop |
+| 10 | b91d92a | ST-1341+1342 | `SprintEditDialog` + multi-OPEN sprints |
+| 11 | 0c36f4e | ST-1344 | `updateSprintAction` regression tests |
+| 12 | 8d6fbdf | bugfix | PBI-rij weer klikbaar voor selectie; vinkje als aparte trigger |
+| 13 | 35c6404 | bugfix | Cascade-restore alleen wanneer hint-story bij nieuwe PBI hoort |
+| 14 | d7d1112 | feat | Sprint-switch auto-select PBI/story + user-settings persist (3 keys) |
+
+### Bugs gevonden tijdens testen (afgehandeld)
+
+1. **Hele PBI-rij was de toggle in selectionMode.** Gevolg: rij-klik bulk-toggled stories en update de teller, maar PBI werd niet als focus geselecteerd → story-kolom bleef leeg.
+   *Fix (8d6fbdf):* in `SortablePbiRow` selectionMode-branch wordt onClick weer `onSelect`; het tri-state icoon zit in een eigen `<button>` met `stopPropagation`.
+2. **Cascade-restore overschrijft PBI-switch.** Bij wisselen naar een andere PBI bleef de oude story (en dus zijn taken) zichtbaar omdat `setActivePbi`'s async hint-restore de vorige story-id terugzette zonder PBI-validatie.
+   *Fix (35c6404):* hint wordt alleen toegepast als `storiesById[hint].pbi_id === pbiId`.
+3. **Tooltip-API mismatch.** `TooltipTrigger` van base-ui accepteert geen `asChild`; geprobeerd via render-prop maar uiteindelijk de hele knop in selectionMode in de Tooltip gewikkeld.
+
+### Nieuwe feature (na implementatie toegevoegd) — sprint-switch auto-select
+
+Bij wisselen van sprint via de switcher wordt **server-side** de inhoud van de sprint geresolved en als deze precies één PBI heeft (en die PBI exact één story binnen de sprint), worden beide automatisch geselecteerd. Alle drie selectie-velden worden atomair in user-settings weggeschreven zodat cross-device-restore klopt.
+
+- Schema: `layout.activePbis` + `layout.activeStories` per product (beide nullable).
+- Helper: `setActiveSelectionInSettings(userId, productId, { sprintId, pbiId?, storyId? })`.
+- Server-action: `switchActiveSprintAction(productId, sprintId)` doet de auto-select-resolutie en returnt het tripel.
+- Sprint-switcher: roept de nieuwe action aan en synchroniseert de client-store gelijk (geen flash).
+- `ActiveSelectionHydrator` (nieuw): client-side effect dat user-settings-activePbi/activeStory naar de workspace-store spiegelt; wint van de bestaande localStorage hint-restore.
+
+### Scope-aanpassing — pendingSprintDraft wordt **session-only**
+
+**Was:** de draft (sprint-doel + per-PBI intent + per-PBI overrides) staat persistent in `user-settings.workflow.pendingSprintDraft` zodat de gebruiker na navigatie kan hervatten.
+
+**Wordt:** de draft leeft alleen in de Zustand-store van de sessie. Bij wegnavigeren krijgt de gebruiker een `useDirtyCloseGuard`-confirm; bij doorgaan wordt de draft **weggegooid** (niet hervat-baar). Reden: de user geeft expliciet aan dat ongeslagen sprints geen rest-state mogen achterlaten in de DB.
+
+Concrete wijzigingen:
+- `lib/user-settings.ts`: `workflow.pendingSprintDraft` kan blijven bestaan voor type-compatibiliteit maar wordt niet meer geschreven door de UI.
+- Actions `setPendingSprintDraftAction` + `clearPendingSprintDraftAction` worden gedeprecieerd (of behouden voor migratie van eventueel oude entries) maar **niet meer aangeroepen** door de UI.
+- Store `useUserSettingsStore.setPendingSprintDraft` / `upsertPbiIntent` / `upsertStoryOverride` blijven bestaan maar de server-roundtrip eruit; lokale state-only.
+- `useDirtyCloseGuard` op het banner-niveau triggert een confirm bij browser-back / route-wissel; bevestigen → `clearPendingSprintDraftAction` (om eventuele oude DB-entries op te ruimen) **+** lokale state-reset.
+
+### Nieuwe feature — draft-sprint zichtbaar in sprint-switcher
+
+Tijdens state A′ (er is een draft) toont de sprint-switcher de **draft-naam** (= `draft.goal`, ingekort) als extra entry bovenaan de dropdown met markering "Concept" of italic-styling. Hij is niet selecteerbaar als "actieve" sprint (want geen sprintId); klikken erop opent de banner-actie of doet niets bijzonders. Doel: visueel feedback geven dat er een onafgemaakte sprint loopt zonder die in de DB op te slaan.
+
+Concreet:
+- Sprint-switcher krijgt prop `pendingDraftGoal?: string | null` (server-side leesbaar via user-settings store na hydration, of via `useUserSettingsStore` in de switcher-component).
+- Render bovenaan de dropdown (boven "— Geen actieve sprint —") wanneer aanwezig: *"⚙ Concept — [goal-prefix]"*.
+
+### Wat blijft staan uit de oorspronkelijke ontwerpkeuzes
+
+- Schema `layout.activeSprints` blijft nullable (key+null = bewust geen sprint).
+- Drie-states-model (A / A′ / B) blijft.
+- Tri-state PBI-vinkje, story-binair-vinkje, cross-sprint disabled blijven.
+- "Sprint opslaan"-knop met teller (state B) blijft.
+- Eligibility-filter + status-mutaties in dezelfde transactie blijven.
+- Endpoints gescoped op `pbiIds` blijven.
+- Multi-OPEN sprints toegestaan blijft.
+
+### Wat nog te doen (na deze plan-update)
+
+> Alle drie punten **afgerond** in commit `2a4ee6a`.
+
+1. ~~**Implementeer scope-aanpassing**~~ — `setPendingSprintDraft` / `clearPendingSprintDraft` zijn nu local-only; `hydrate()` strip eventuele legacy DB-entries.
+2. ~~**Sprint-switcher concept-entry**~~ — `⚙ Concept — [goal]` verschijnt bovenaan de dropdown zodra er een draft loopt.
+3. ~~**Verifieer**~~ — `npm run verify` groen (826 tests). `SprintDraftLeaveGuard` registreert `beforeunload`-listener voor browser-refresh/close. In-app route-changes blijven via banner-Annuleren lopen.
+
+### Bewust niet geïmplementeerd
+
+- **Server-side persist van manuele PBI/story-klikken.** Vraag: "wordt de geselecteerde pbi ook opgeslagen". Antwoord: nee, momenteel alleen via sprint-switch auto-select. Manuele klikken gaan naar localStorage. Cross-device parity voor manuele klikken vereist extra server-roundtrips per klik; de helpers `setActivePbiInSettings` / `setActiveStoryInSettings` zijn voorbereid maar niet gewired. Op verzoek opnieuw oppakken in een vervolg-PBI.
+
+### localStorage-gebruik (overzicht)
+
+| Locatie | Doel |
+|---|---|
+| [stores/product-workspace/restore.ts](stores/product-workspace/restore.ts) | Per-browser hints `lastActivePbiId` / `lastActiveStoryId` / `lastActiveTaskId` per product. |
+| [stores/sprint-workspace/restore.ts](stores/sprint-workspace/restore.ts) | Idem voor de sprint-pagina. |
+| [lib/user-settings-migration.ts](lib/user-settings-migration.ts) | One-shot migratie van legacy prefs (PBI-76) naar user-settings. |
+| [components/ideas/idea-md-editor.tsx](components/ideas/idea-md-editor.tsx) | Auto-save van idee-markdown-draft (niet PBI-79-gerelateerd). |
+
+`ActiveSelectionHydrator` (PBI-79) wint van de localStorage-hints voor PBI/story-selectie zodra user-settings expliciet iets bevat.
+
+---
+
+## Context
+
+De Product Backlog-pagina (`/products/[id]`) is het hart van Scrum4Me. De **lazy-load-basis bestaat al** (filter-first/background-remaining-PBI's + lazy stories/tasks per klik via [lib/product-backlog-pbis.ts](lib/product-backlog-pbis.ts), `ensurePbiLoaded`, `ensureStoryLoaded`). Dit plan bouwt daarop voort, het herontwerpt dat fundament niet.
+
+Wat nog ontbreekt:
+
+1. **Geen uniforme sprint-samenstelling-UI**. Sprint-aanmaak loopt nu via twee flows: `createSprintAction` (één pbi_id) en `createSprintWithPbisAction` (array, via `NewSprintDialog`). Geen UI-feedback over welke PBI's al in welke mate "in de huidige sprint zitten".
+2. **Stories aan/uit sprint per stuk** kan alleen via de Sprint-pagina, niet vanuit de backlog.
+3. **Geen pending/dirty-flow** voor sprint-mutaties — alle huidige acties zijn direct gecommit, wat zware multi-toggle-flows omslachtig maakt.
+
+We bouwen een vinkje-gebaseerde workflow met drie states. Geen schemamutatie op de DB — `sprint_id` blijft op Story en Task. PBI-vinkjes zijn puur afgeleid. `task.sprint_id` blijft denormalisatie van `story.sprint_id` en wordt cascade-meeg­e­update bij bulk-mutaties.
+
+---
+
+## Beslissingen (samenvatting)
+
+| Onderdeel | Keuze |
+|---|---|
+| **Datamodel** | Ongewijzigd. `story.sprint_id` is unit-of-truth; PBI/task vinkjes afgeleid |
+| **Cross-sprint conflict** | Disabled vinkje + tooltip; **alleen** tegen andere OPEN sprints |
+| **State A** (geen sprint) | Alle PBI's, geen vinkjes, klassieke 3-koloms inspect |
+| **State A′ vorm** | Two-step: kleine modal (metadata) → sticky banner + inline vinkjes |
+| **State A′ annuleren** | Dirty-close confirm (`useDirtyCloseGuard`-pattern) |
+| **State A′ persistentie** | `user-settings.pendingSprintDraft[productId]` — compacte intent (zie hieronder), niet alle story-IDs |
+| **Lege sprint** | Toegestaan |
+| **State B vinkjes** | Tri-state op PBI (selector-afgeleid), binair op story; klikken muteert pending buffer |
+| **State B pending scope** | Alleen sprint-membership toggles |
+| **State B dirty-UI** | "Sprint opslaan"-knop altijd zichtbaar, disabled bij clean, met teller bij dirty |
+| **State B navigatie bij dirty** | Confirm-dialog |
+| **Sprint-switcher** | OPEN sprints + "Geen actieve sprint"-optie. CLOSED via bestaande sprint-pagina |
+| **Sprint-scope** | Per-user (huidig `user-settings.activeSprints[productId]`) |
+| **Multiple OPEN sprints** | Toegestaan — `createSprintAction`-uniqueness-check vervalt |
+| **Nieuwe story in state B** | `sprint_id = activeSprintId` direct bij aanmaak |
+| **Tasks-niveau** | Geen vinkjes. Cascade-meeg­e­updated met story |
+| **Sprint metadata edit** | `SprintEditDialog` (goal, dates) via edit-icoon |
+| **Sprint afsluiten** | Hergebruik bestaande `completeSprintAction` (per-story DONE/OPEN beslissing + PBI-promotie) — **niet** een nieuwe `closeSprintAction` |
+| **`story.status` bij membership-mutaties** | Add: `status='IN_SPRINT'` (én `sprint_id` gezet). Remove: `status='OPEN'` (én `sprint_id=NULL`). `task.sprint_id` cascadeert in **dezelfde transactie** |
+| **Eligibility voor toevoegen** | Server-resolve mag alleen stories met `sprint_id IS NULL` **en** `status != 'DONE'` toevoegen. Stories uit CLOSED/ARCHIVED/FAILED sprints met DONE-status zijn dus niet eligible — moeten eerst handmatig op OPEN gezet worden (of via re-open flow) |
+| **Active-sprint null-contract** | Schema nullable maken — `activeSprints[productId]: string \| null`. **Key-aanwezigheid heeft betekenis**: key ontbreekt → fallback-cascade (eerste OPEN, dan recent CLOSED). Key met `null`-waarde → expliciet *geen* actieve sprint, géén fallback |
+| **PBI-selectie-flow migratie** | Bestaande `selectionMode` + `NewSprintDialog` + `createSprintWithPbisAction` worden **omgebouwd** tot A′-draft-mode. Eén flow, geen feature-flag-parallellisme |
+| **Initial server-side load** | Bestaande `getProductBacklogPbis(productId, query, 'matching')` blijft basis — geen counts in deze call. Geen stories, geen taken |
+| **Background remaining-load** | Behoud huidige patroon: client laadt `?mode=remaining` via route handler |
+| **PBI-counts (state B tri-state)** | Aparte lazy summary-endpoint `GET /api/products/[id]/sprint-membership-summary?sprintId=X&pbiIds=<ids>` — **expliciet gescoped op pbiIds** (visible/loaded batch), nooit product-breed. Alleen aangeroepen in state B |
+| **Story-detail (description + taken)** | Lazy bij PBI-klik via bestaande `ensurePbiLoaded`/`ensureStoryLoaded` route handlers |
+| **Story-IDs voor A′ tri-state** | **Niet** brede `getStoryIdsByPbi(productId)`-fetch. Per PBI lazy via dezelfde `ensurePbiLoaded` als state A |
+| **Cross-sprint conflict-detectie** | Server-side bij commit (autoritatief). Client-hint via lichte `GET /api/products/[id]/cross-sprint-blocks?excludeSprintId=X&pbiIds=<ids>` — **gescoped op pbiIds** voor disabled-vinkjes |
+| **Data-access stijl** | Blijven bij **route handlers + `cache: 'no-store'` + `revalidatePath`** (huidige stijl). Géén Cache Components / `'use cache'` / `cacheTag` in dit plan |
+| **Sync na commit** | Server action retourneert affected ids → client patcht workspace-store gericht. **Geen `router.refresh()` of full page rehydration** |
+
+---
+
+## State A — geen actieve sprint geselecteerd
+
+**UI:** bestaande 3-koloms layout uit [components/backlog/backlog-split-pane.tsx](components/backlog/backlog-split-pane.tsx) onveranderd. PBI-lijst | Story-panel | Task-panel. Geen vinkjes.
+
+**Header-acties:** sprint-switcher toont "Geen actieve sprint" + dropdown van OPEN sprints + "— Geen actieve sprint —"-optie. Naast switcher: knop **"Nieuwe sprint"** → start A′ door metadata-modal te openen.
+
+**Wijzigingen t.o.v. huidig gedrag:**
+- Sprint-switcher in [components/shared/sprint-switcher.tsx](components/shared/sprint-switcher.tsx) krijgt expliciete optie "— Geen actieve sprint —"; selectie roept (nieuwe) `clearActiveSprintAction(productId)` aan → schrijft `null` in user-settings.
+- De huidige "Start Sprint"-knop in [app/(app)/products/[id]/page.tsx](app/(app)/products/[id]/page.tsx) wordt "Nieuwe sprint" en triggert A′-flow i.p.v. direct `NewSprintDialog`.
+
+---
+
+## State A′ — sprint definiëren (ombouw van huidige selectionMode)
+
+### Migratie-uitgangspunt
+
+De bestaande PBI-selectie-flow in [components/backlog/pbi-list.tsx:219-523](components/backlog/pbi-list.tsx) heeft al:
+- `selectionMode` boolean en `selectedIds: Set<string>`
+- `toggleCheck(id)` voor PBI-toggles
+- `exitSelection()` voor cleanup
+- `NewSprintDialog` aanroep met `pbiIds`-array
+- Server-action `createSprintWithPbisAction` die alle stories van geselecteerde PBI's bulk-update
+
+We **bouwen dit om** tot A′. Het oude `NewSprintDialog` wordt vervangen door de two-step flow (metadata-modal → banner). De selectie-state wordt uitgebreid van "PBI's only" naar "PBI's én individuele stories (overrides)". `createSprintWithPbisAction` wordt aangepast om óók override-lijsten te accepteren.
+
+### Stap 1: metadata-modal
+
+Klik "Nieuwe sprint" → kleine `Dialog` (Entity-Dialog-pattern uit [docs/patterns/dialog.md](docs/patterns/dialog.md)):
+- **Sprint-doel** (`sprint_goal`, verplicht)
+- **Startdatum** (optioneel, default = vandaag)
+- **Einddatum** (optioneel, default = +2 weken)
+- Knoppen: "Annuleren" | "Verder"
+
+"Verder" valideert (Zod) en schrijft via `setPendingSprintDraftAction` naar user-settings. **Geen sprint in DB.**
+
+### Stap 2: vinkjes + sticky banner (compacte intent-state)
+
+Op de pagina verschijnt een **sticky banner**:
+```
+┌──────────────────────────────────────────────────────────────────┐
+│ Sprint definiëren — [doel] · X PBI's, Y stories                  │
+│                                  [Annuleren] [Sprint aanmaken] │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Op alle PBI-rijen en story-rijen verschijnen vinkjes — story-vinkjes pas zichtbaar als de PBI is geopend (via bestaande `ensurePbiLoaded`).
+
+**Pending draft-state (compact, overrides per PBI):**
+
+```ts
+pendingSprintDraft: {
+  goal: string
+  startAt?: string
+  endAt?: string
+  // Per-PBI bulk-intent:
+  pbiIntent: {
+    [pbiId]: 'all' | 'none'    // default 'none' tot user PBI aanvinkt
+  }
+  // Per-PBI overrides (story-ids die afwijken van de PBI-intent):
+  storyOverrides: {
+    [pbiId]: {
+      add: string[]       // expliciet aan, ook al staat PBI op 'none'
+      remove: string[]    // expliciet uit, ook al staat PBI op 'all'
+    }
+  }
+}
+```
+
+**Waarom per-PBI overrides (i.p.v. één globale add/remove):** bij PBI-toggle (`'all' → 'none'`) of bij sessie-restore moet je zonder brede story-fetch betrouwbaar weten welke overrides bij welke PBI horen. Globale lijsten dwingen je tot een product-breed `getStoryIdsByPbi` om op te schonen — dat is precies wat we niet willen. Met per-PBI overrides is opruimen lokaal: bij PBI-toggle wis je `storyOverrides[pbiId]`, klaar.
+
+**Tri-state-resolutie (selector, niet opgeslagen):**
+- PBI-vinkje weergave: bereken uit `pbiIntent[pbiId]` + de subset van zijn child-stories die geladen is + `storyOverrides[pbiId]`. Bij `intent='all'` en geen `remove` → ✓. Bij `intent='none'` en geen `add` → ☐. Anders ◐.
+- Story-vinkje: `(pbiIntent[pbiId] == 'all' || storyOverrides[pbiId]?.add?.includes(storyId)) && !storyOverrides[pbiId]?.remove?.includes(storyId)`.
+
+**Toggle-semantiek:**
+- Klik PBI-vinkje ☐→✓: `pbiIntent[pbi] = 'all'`, wis `storyOverrides[pbi]`.
+- Klik PBI-vinkje ✓→☐: `pbiIntent[pbi] = 'none'`, wis `storyOverrides[pbi]`.
+- Klik story-vinkje (in geopende PBI): voeg toe aan `storyOverrides[pbi].add` of `.remove`, met cancel-out tegen de tegenoverliggende lijst van diezelfde PBI.
+
+**Voordelen:** geen N×K JSON-blob per draft. Per-PBI scoping maakt cleanup lokaal en restore deterministisch.
+
+**Annuleren** → dirty-close confirm → `clearPendingSprintDraftAction` → banner verdwijnt.
+
+**Sprint aanmaken** → server action `createSprintWithSelectionAction(productId, metadata, pbiIntent, storyOverrides)`:
+1. Server resolveert intent → concrete `storyIdsToAddToSprint: string[]`:
+   - Voor elke PBI met `intent = 'all'`: alle child-stories minus `storyOverrides[pbi].remove`
+   - Plus alle stories in `storyOverrides[pbi].add` (over alle PBI's)
+2. **Eligibility-filter (server, autoritatief):** behoud alleen stories waarvoor `sprint_id IS NULL` **en** `status != 'DONE'`. Stories die niet voldoen (in andere sprint, of al DONE) komen in `conflicts.notEligible[]` met reden.
+3. **Cross-sprint-check** (gedekt door eligibility, maar separately rapporteren): geblokkeerde stories → `conflicts.crossSprint[]` met `{ storyId, sprintId, sprintName }`.
+4. Transactie:
+   - Insert Sprint (status=OPEN)
+   - `story.sprint_id = newSprintId, story.status = 'IN_SPRINT' WHERE id IN (eligibleStoryIds)`
+   - `task.sprint_id = newSprintId WHERE story_id IN (eligibleStoryIds)` (cascade — task.status onveranderd)
+5. `clearPendingSprintDraftAction` + `setActiveSprintInSettings(productId, newSprintId)`
+6. Realtime-event broadcasting
+7. **Return:** `{ sprintId, affectedStoryIds, affectedPbiIds, conflicts: { notEligible, crossSprint } }`
+8. Client patcht workspace-store gericht: voeg sprintId toe aan stories/tasks, zet `story.status = 'IN_SPRINT'`, invalidate `pbiSummary`-counts voor affected PBI's via lazy summary-refetch (gescoped). Toast voor conflicts. **Geen page-refresh.**
+
+### Persistent draft
+
+Verlaten van de pagina/sessie tijdens A′ → `pendingSprintDraft` blijft in user-settings. Volgende bezoek: pagina detecteert draft → banner + vinkjes verschijnen automatisch.
+
+---
+
+## State B — actieve sprint geselecteerd
+
+### UI
+
+- **Header**: sprint-switcher toont actieve sprint. Edit-icoon ernaast → opent `SprintEditDialog` (alleen metadata: goal + dates).
+- **"Sprint opslaan"-knop**: altijd zichtbaar, disabled bij clean, geactiveerd met teller bij dirty: *"Sprint opslaan (3)"*.
+- **Sprint afsluiten**: bestaande `completeSprintAction`-flow blijft op de sprint-pagina (`/products/[id]/sprint/[sprintId]`); SprintEditDialog krijgt een link "Sprint afronden…" die naar die pagina navigeert. Geen duplicate flow.
+- **3-koloms layout**: ongewijzigd. PBI-vinkjes (tri-state via selector), story-vinkjes (binair, disabled-bij-conflict), geen task-vinkjes.
+
+### Pending buffer (state B)
+
+In [stores/product-workspace/store.ts](stores/product-workspace/store.ts) toevoegen — **arrays, niet Sets**:
+
+```ts
+sprintMembershipPending: {
+  adds: string[]      // story-ids die in actieve sprint moeten
+  removes: string[]   // story-ids die uit actieve sprint moeten
+}
+```
+- `isDirty` selector: `adds.length + removes.length > 0`
+- Teller selector: `adds.length + removes.length`
+- Cancel-out: bij toggle terug wordt het ID uit de tegenoverliggende lijst gehaald
+
+Arrays zijn JSON-serialiseerbaar (handig voor debugging/devtools) en spelen netjes met Zustand/Immer (geen mutable Set-valkuil).
+
+### Tri-state vinkjes via selectors (geen opgeslagen state)
+
+In [stores/product-workspace/store.ts](stores/product-workspace/store.ts):
+
+```ts
+// Primitieven (opgeslagen):
+pbiSummary: {
+  [pbiId]: {
+    totalStoryCount: number              // uit summary-endpoint
+    inActiveSprintStoryCount: number     // uit summary-endpoint, of 0 in state A
+  }
+}
+loadedStoryIdsByPbi: { [pbiId]: string[] }   // alleen voor stories die al geladen zijn
+storiesByPbi: { [pbiId]: Story[] | undefined }
+tasksByStory: { [storyId]: Task[] | undefined }
+sprintMembershipPending: { adds: string[], removes: string[] }
+crossSprintBlocks: { [storyId]: { sprintId: string, sprintName: string } }  // lazy
+
+// Selectors (afgeleid, gememoized):
+selectPbiTriState(pbiId): 'empty' | 'partial' | 'full'
+selectStoryEffectiveInSprint(storyId): boolean
+selectStoryIsBlocked(storyId): { sprintId, sprintName } | null
+```
+
+`selectPbiTriState` rekent met `inActiveSprintStoryCount` + pending adds/removes voor stories van deze PBI (waarvan we de mapping kennen via `loadedStoryIdsByPbi` of via een lichte query bij PBI-load). Als de PBI niet geladen is, kan tri-state worden afgeleid uit de counts alleen (full = count==total, empty = count==0, partial = anders).
+
+### Sprint opslaan
+
+Server action `commitSprintMembershipAction(activeSprintId, adds[], removes[])`:
+1. **Eligibility-filter voor `adds` (server, autoritatief):** behoud alleen stories met `sprint_id IS NULL` **en** `status != 'DONE'`. Niet-eligible stories (cross-sprint-conflict, of DONE) komen in `conflicts.notEligible[]`.
+2. **`removes`-filter:** behoud alleen stories die feitelijk `sprint_id = activeSprintId` hebben (race-safety; story kan ondertussen al ergens anders heen verplaatst zijn).
+3. Transactie:
+   - **Add**: `story.sprint_id = activeSprintId, story.status = 'IN_SPRINT' WHERE id IN (eligibleAdds)`
+   - **Add**: `task.sprint_id = activeSprintId WHERE story_id IN (eligibleAdds)` (cascade, task.status onveranderd)
+   - **Remove**: `story.sprint_id = NULL, story.status = 'OPEN' WHERE id IN (validRemoves)`
+   - **Remove**: `task.sprint_id = NULL WHERE story_id IN (validRemoves)` (cascade)
+4. Realtime-events broadcasten
+5. **Return:** `{ affectedStoryIds, affectedPbiIds, affectedTaskIds, conflicts: { notEligible, alreadyRemoved } }`
+6. Client patcht store gericht:
+   - Update `story.sprint_id` + `story.status` voor affected stories in `storiesById` / `storiesByPbi`
+   - Update `task.sprint_id` voor affected tasks
+   - Debounced refetch van `sprint-membership-summary` voor affected PBI's (**gescoped op `pbiIds=affectedPbiIds`**)
+   - Wis pending buffer
+   - Toast voor conflicts
+   - **Geen `router.refresh()`.**
+
+### Andere mutaties in state B
+
+- **Story aanmaken** (StoryDialog): `sprint_id = activeSprintId` direct bij create. Verschijnt direct in sprint.
+- **PBI/Story/Task field-edit** (bestaande Entity Dialogs): onveranderd.
+- **Sprint-switcher wisselt bij dirty**: confirm-dialog.
+- **Wegnavigeren met dirty**: `useDirtyCloseGuard` → confirm-dialog.
+
+---
+
+## Cross-sprint conflict — afhandeling
+
+**Client (hint-laag):** lazy fetch `GET /api/products/[id]/cross-sprint-blocks?excludeSprintId=X` bij state-B-load. Vult `crossSprintBlocks` in de store. Story-rij met `crossSprintBlocks[storyId] != null` → vinkje disabled, tooltip "Zit in Sprint [naam]".
+
+**Server (autoritatieve check):** in `commitSprintMembershipAction` en `createSprintWithSelectionAction` opnieuw checken — race-conditie wordt afgevangen, conflicts worden geretourneerd als warning. Client toont toast voor geskippte stories.
+
+Helper `lib/sprint-conflicts.ts` (nieuw) doet de check op een set story-IDs en geeft `{ allowed: string[], blocked: { storyId, sprintId, sprintName }[] }`.
+
+---
+
+## SprintEditDialog (nieuw)
+
+`components/backlog/sprint-edit-dialog.tsx` — Entity-Dialog-pattern:
+- Velden: `sprint_goal`, `start_at`, `end_at`
+- Knop "Opslaan" → `updateSprintAction(sprintId, fields)`
+- Link "Sprint afronden…" → navigeert naar `/products/[id]/sprint/[sprintId]` (bestaande sprint-page met `completeSprintAction`)
+- **Geen** "Sprint afsluiten"-knop hier — hergebruik bestaande completion-flow met per-story DONE/OPEN beslissing en PBI-promotie.
+
+Server action `updateSprintAction(sprintId, { goal?, start_at?, end_at? })`: validate met Zod, update Sprint-record, `revalidatePath('/products/[id]')`, retourneert affected sprint. Client patcht sprint-record in store.
+
+---
+
+## Dataflow
+
+### Uitgangspunten
+
+- **Blijf bij route handlers + `cache: 'no-store'`** (huidige patroon). Geen `'use cache'`/`cacheTag` in deze migratie — review's P2 zegt: meng deze stijlen niet half. Migratie naar Cache Components is een eigen project.
+- **Filter-first respecteren**: initial render levert alleen *matching* PBI-metadata; *remaining* op de achtergrond — beide via bestaande [getProductBacklogPbis](lib/product-backlog-pbis.ts).
+- **Geen aggregaten in initial query**: dat zou bij groei alsnog brede story-aggregaties bij elke render forceren.
+- **Counts apart via lazy endpoint**: alleen voor state B, alleen voor zichtbare PBI's (of bulk per sprint — beheerbaar omdat #PBI's per product bescheiden blijft).
+- **Geen brede `getStoryIdsByPbi`**: hergebruik bestaande `ensurePbiLoaded`/`ensureStoryLoaded` lazy-loads. Tri-state werkt op counts (uit summary-endpoint) zolang de PBI dichtgeklapt is; pas bij open-klik komen story-IDs in beeld voor accurate selector-state.
+- **Sync-model**: SSE-patches (al aanwezig) voor reactieve updates + `revalidatePath` na server-actions (huidige patroon) + gerichte client-store patches met de affected-IDs uit action-returns.
+
+### Initial server-side load (page render)
+
+Onveranderd t.o.v. huidige flow — geen nieuwe loader:
+
+```ts
+// app/(app)/products/[id]/page.tsx (huidige code, behouden):
+const initialPbiQuery = productBacklogPbiQueryFromSettings(...)
+const pbis = await getProductBacklogPbis(id, initialPbiQuery, 'matching')
+// Geen stories, geen taken in initial render.
+```
+
+Plus parallel:
+- `activeSprint = resolveActiveSprint(productId, userId)` — gewijzigd om explicit `null` te respecteren (zie hieronder).
+- `pendingSprintDraft = getUserSettings(userId).pendingSprintDraft?.[productId] ?? null`.
+
+### Background remaining-load
+
+Bestaande route handler `GET /api/products/[id]/backlog?mode=remaining` blijft. Client triggert na initial render om de overige PBI-metadata in de store te krijgen (zonder stories/tasks).
+
+### Lazy per PBI-klik
+
+Bestaande `ensurePbiLoaded(pbiId)` in [stores/product-workspace/store.ts](stores/product-workspace/store.ts) blijft. Fetch via route handler met `cache: 'no-store'`. Vult `storiesByPbi[pbiId]` + `loadedStoryIdsByPbi[pbiId]`.
+
+### Lazy per story-klik
+
+Bestaande `ensureStoryLoaded(storyId)` blijft (laadt taken).
+
+### Sprint-membership summary (NIEUW — alleen state B, gescoped)
+
+Nieuw route handler `GET /api/products/[id]/sprint-membership-summary?sprintId=X&pbiIds=<comma-separated>`:
+```ts
+// Response:
+{
+  [pbiId: string]: { total: number, inSprint: number }
+}
+```
+
+- **`pbiIds` is verplicht** — endpoint weigert product-brede aanroepen. Client geeft alleen visible/loaded PBI-IDs door.
+- Eén `groupBy` op `Story` waar `pbi_id IN (pbiIds)` (matching-filter werkt nog: we vragen alleen counts voor PBI's die al in viewport-batch staan).
+- Verwaarloosbare belasting omdat de query begrensd is op de doorgegeven set.
+
+Aangeroepen door client wanneer state B actief wordt OF na sprint-switch, OF na een commit (gescoped op affected pbi-ids). Vult `pbiSummary` in de store.
+
+In state A wordt **niet** aangeroepen.
+
+### Cross-sprint blocks (NIEUW — alleen state B, gescoped)
+
+Nieuw route handler `GET /api/products/[id]/cross-sprint-blocks?excludeSprintId=X&pbiIds=<comma-separated>`:
+```ts
+{
+  [storyId: string]: { sprintId: string, sprintName: string }
+}
+```
+
+- **`pbiIds` verplicht** — endpoint weigert product-brede scans. Begrenzing op visible/loaded batch.
+- Aangeroepen bij state B-load + na elke PBI-batch-load (zodat nieuwe PBI's hun blocks krijgen).
+- Vult `crossSprintBlocks` in de store voor disabled-vinkjes.
+- Server-side check bij commit blijft autoritatief — dit endpoint is alleen UX-hint.
+
+### Active-sprint resolver (gewijzigd)
+
+**Schema-contract (cruciaal, zit in [lib/user-settings.ts](lib/user-settings.ts)):**
+
+```ts
+// Zod schema wijziging:
+activeSprints: z.record(z.string(), z.string().nullable()).optional()
+```
+
+**Drie distincte states per `productId`:**
+
+| Settings-staat | Betekenis |
+|---|---|
+| Key ontbreekt | Geen voorkeur ingesteld — fallback-cascade actief (eerste OPEN, dan recent CLOSED, dan `null`) |
+| Key bestaat met `string` | Die specifieke sprint is gekozen (mits gevonden in DB; anders fallback) |
+| Key bestaat met `null` | **Bewust geen actieve sprint** — geen fallback, blijft "Geen actieve sprint" |
+
+**Wijzigingen in [lib/active-sprint.ts](lib/active-sprint.ts):**
+- `resolveActiveSprint(productId, userId)` checkt `key in activeSprints` (niet alleen truthy):
+   - Key niet aanwezig → fallback-cascade
+   - Key aanwezig, value=null → return null
+   - Key aanwezig, value=string → die sprint
+- `setActiveSprintInSettings(productId, sprintId)` ongewijzigd (schrijft string).
+- **`clearActiveSprintInSettings(productId)` wordt aangepast**: i.p.v. de key te `delete`, schrijft het nu `null`. Dat is het verschil tussen "geen voorkeur" en "expliciet geen actieve sprint".
+
+**[actions/active-sprint.ts](actions/active-sprint.ts):**
+- Nieuw: `clearActiveSprintAction(productId)` — gebruikt de aangepaste `clearActiveSprintInSettings` (schrijft null).
+- Bestaande `setActiveSprintAction` ongewijzigd.
+
+### Sync na commit — gerichte client-store patches
+
+Server actions retourneren expliciet affected IDs:
+```ts
+return { affectedStoryIds, affectedPbiIds, affectedTaskIds, conflicts }
+```
+
+Client (na await):
+1. Patch `storiesById` + `tasksById` met nieuwe `sprint_id`-waarden.
+2. Voor elke `affectedPbiId`: fire-and-forget refetch van `sprint-membership-summary` (debounced 100ms) om counts te actualiseren.
+3. Wis pending buffer.
+4. **Geen `router.refresh()`.**
+
+`revalidatePath` blijft in de server-actie voor andere users / lossely-coupled views, maar de huidige user's UI updateert via de gerichte patches.
+
+### Data-load-volgorde overzicht
+
+| Moment | Wat | Wie |
+|---|---|---|
+| Page render | Matching PBI's (metadata) + activeSprint + draft | Server (SSR) — bestaande flow |
+| Na hydratie | Remaining PBI's (metadata) | Client → bestaande `/api/.../backlog?mode=remaining` |
+| State B activeert | Sprint-membership-summary + cross-sprint-blocks | Client → nieuwe endpoints |
+| PBI-klik | Stories voor die PBI (full) | Client → bestaande `ensurePbiLoaded` |
+| Story-klik | Taken voor die story | Client → bestaande `ensureStoryLoaded` |
+| A→A′ start | Geen extra fetch — werk met `pendingSprintDraft` (compact) |  |
+| A′ stories cherrypicken | Klik PBI → bestaande lazy-load voor die PBI |  |
+| Sprint-switch | Refetch membership-summary + cross-sprint-blocks voor nieuwe sprint | Client |
+| SSE event | Patch lokale store | Client |
+| Na server-action commit | Affected IDs uit return → gerichte store-patches + debounced summary-refetch | Client |
+
+---
+
+## Critical files
+
+### Te wijzigen
+
+- [app/(app)/products/[id]/page.tsx](app/(app)/products/[id]/page.tsx) — state-detectie (A/A′/B); banner-rendering; "Nieuwe sprint"-knop opent metadata-modal (i.p.v. direct `NewSprintDialog`). **Initial query blijft `getProductBacklogPbis(id, query, 'matching')`** — geen counts hier.
+- [components/backlog/pbi-list.tsx](components/backlog/pbi-list.tsx) — bestaande `selectionMode` ombouwen tot A′-modus: vinkjes worden tri-state, lezen uit `pendingSprintDraft.pbiIntent` of (in state B) uit `selectPbiTriState`-selector. Verwijder de directe `NewSprintDialog`-trigger.
+- [components/backlog/story-panel.tsx](components/backlog/story-panel.tsx) — vinkje per story; lees uit selectors (`selectStoryEffectiveInSprint`, `selectStoryIsBlocked`); klik muteert `pendingSprintDraft.storyOverrides` of `sprintMembershipPending`.
+- [components/backlog/task-panel.tsx](components/backlog/task-panel.tsx) — geen wijzigingen aan task-flow.
+- [components/shared/sprint-switcher.tsx](components/shared/sprint-switcher.tsx) — "— Geen actieve sprint —"-optie; dirty-check bij wissel.
+- [stores/product-workspace/store.ts](stores/product-workspace/store.ts) — uitbreidingen: `pbiSummary`, `loadedStoryIdsByPbi`, `crossSprintBlocks`, `sprintMembershipPending` (arrays), selectors voor tri-state, gerichte patch-helpers voor server-action-returns.
+- [stores/user-settings/store.ts](stores/user-settings/store.ts) — `pendingSprintDraft[productId]: { goal, startAt?, endAt?, pbiIntent, storyOverrides: { [pbiId]: { add, remove } } } | null`; `activeSprints[productId]: string | null` (zie ook user-settings.ts hieronder).
+- **[lib/user-settings.ts](lib/user-settings.ts)** — Zod-schema strictness: `activeSprints` value nullable; `pendingSprintDraft` als optionele key per productId met de hier-gespecificeerde shape; migratie-tests aanpassen.
+- [actions/sprints.ts](actions/sprints.ts):
+   - `createSprintAction` — drop OPEN-uniqueness-check (multi-OPEN toegestaan)
+   - **`createSprintWithPbisAction` → uitbreiden naar `createSprintWithSelectionAction(productId, metadata, pbiIntent, storyOverrides)`**. Server resolveert intent → concrete story-IDs. Returnt affected IDs.
+   - Nieuw: `commitSprintMembershipAction(sprintId, adds[], removes[])` — transactional, retourneert affected + conflicts.
+   - Nieuw: `updateSprintAction(sprintId, { goal?, startAt?, endAt? })` — alleen metadata.
+   - **GEEN** nieuwe `closeSprintAction` — `completeSprintAction` blijft de afrond-flow.
+- [actions/active-sprint.ts](actions/active-sprint.ts) — nieuwe `clearActiveSprintAction(productId)` (schrijft null). `setActiveSprintAction` ongewijzigd voor non-null.
+- [lib/active-sprint.ts](lib/active-sprint.ts) — `resolveActiveSprint` checkt key-aanwezigheid (niet truthy): key+null → return null zonder fallback; key+string → sprint; key ontbreekt → fallback-cascade. **`clearActiveSprintInSettings` schrijft nu `null` i.p.v. key te verwijderen** (essentieel voor het null-contract).
+
+### Nieuw
+
+- `app/api/products/[id]/sprint-membership-summary/route.ts` — lazy counts endpoint
+- `app/api/products/[id]/cross-sprint-blocks/route.ts` — lazy cross-sprint hint endpoint
+- `components/backlog/sprint-definition-banner.tsx` — sticky banner voor A′
+- `components/backlog/new-sprint-metadata-dialog.tsx` — stap 1 van A′
+- `components/backlog/sprint-edit-dialog.tsx` — metadata-edit in B
+- `lib/sprint-conflicts.ts` — cross-sprint check helpers
+- `actions/sprint-draft.ts` — `setPendingSprintDraftAction`, `clearPendingSprintDraftAction`
+
+### Niet aangeraakt
+
+- [prisma/schema.prisma](prisma/schema.prisma) — geen schemawijziging
+- Bestaande `completeSprintAction` en de sprint-pagina `/products/[id]/sprint/[sprintId]` — sprint-afronding-flow blijft daar
+- [components/backlog/task-panel.tsx](components/backlog/task-panel.tsx), task-dialog, pbi-dialog, story-dialog — Entity Dialogs onveranderd
+
+---
+
+## Hergebruik bestaande patronen
+
+- **Entity-Dialog-pattern**: metadata-modal + sprint-edit-dialog
+- **useDirtyCloseGuard**: A′-annulering, B-navigatie
+- **Zustand optimistic pattern**: pending buffer + gerichte server-action-return-patches
+- **Realtime NOTIFY-payload**: sprint-membership events
+- **Server-action-pattern**: auth + Zod
+- **Filter-first/background-remaining**: blijft via [getProductBacklogPbis](lib/product-backlog-pbis.ts) en bestaande `/api/products/[id]/backlog?mode=X` route handler
+- **MD3-tokens + shadcn `<Checkbox>`** (tri-state via custom mapping)
+
+---
+
+## Verificatie
+
+### End-to-end checks (handmatig + dev-server)
+
+1. **State A pad**: zonder actieve sprint → geen vinkjes, switcher toont "Geen actieve sprint", klik PBI → stories tonen, klik story → taken tonen, Entity-Dialog edits direct gecommit.
+
+2. **A → A′ → B happy path**: "Nieuwe sprint" → metadata-modal → "Verder" → banner verschijnt, vinkjes verschijnen op PBI's. Vink 2 PBI's met 5 child-stories totaal → banner toont "2 PBI's, 5 stories". Open één PBI en deselecteer 1 story (storyOverride.remove). Banner: "2 PBI's, 4 stories". Klik "Sprint aanmaken" → sprint actief, state B met afgeleide vinkjes, **geen page refresh** (controle via DevTools Network: alleen affected updates).
+
+3. **A′ persistente draft**: start A′, vink dingen aan, navigeer weg → confirm-dialog → bevestig. Kom terug op pagina → banner + vinkjes hersteld.
+
+4. **State B pending buffer**: vink een story aan → "Sprint opslaan (1)". Vink een story in sprint weg → "Sprint opslaan (2)". Vink eerste weer uit → "Sprint opslaan (1)" (cancel-out). Klik opslaan → store-patches, geen full reload.
+
+5. **Cross-sprint blokkade**: maak twee OPEN sprints, story X in sprint A. Switch naar sprint B → story X heeft disabled vinkje, tooltip "Zit in Sprint [A]". Verplaats story X via sprint A's sprint-page → cross-sprint-blocks updaten via SSE-patch.
+
+6. **Sprint metadata-edit**: edit-icoon → SprintEditDialog → wijzig goal → opslaan → direct gecommit, geen page-state-wijziging.
+
+7. **Sprint afronden**: SprintEditDialog toont link "Sprint afronden…" → navigeert naar `/products/[id]/sprint/[sprintId]` → bestaande completion-flow ongewijzigd.
+
+8. **Switcher-wissel bij dirty**: state B met pending toggles → wissel sprint → confirm-dialog. Cancel → blijft, buffer intact. Bevestig → buffer leeg, switch.
+
+9. **"Geen actieve sprint" persistentie**: kies "— Geen actieve sprint —" in switcher → schrijf null. Refresh pagina → blijft state A, valt **niet** terug op nieuwste OPEN sprint.
+
+### Geautomatiseerde tests (Vitest)
+
+- `lib/sprint-conflicts.test.ts`: vrij, in-zelfde-sprint, in-andere-OPEN, in-CLOSED (niet blokkerend voor commit-laag).
+- `stores/product-workspace.test.ts`: pending buffer (arrays) toggle-cancel-out; tri-state-selector op verschillende load-staten (PBI niet geladen / geladen / met per-PBI overrides).
+- `actions/sprints.test.ts`:
+   - `createSprintWithSelectionAction` resolve van per-PBI intent + per-PBI storyOverrides
+   - **Eligibility-filter**: stories met `status='DONE'` of `sprint_id != NULL` worden geweigerd en komen in `conflicts.notEligible`
+   - **Status-mutatie**: na add zijn betroffen stories `IN_SPRINT`; na remove zijn ze `OPEN`
+   - **Task.sprint_id in dezelfde transactie** — assert via mock prisma dat beide updates één tx delen
+   - Returns met `affectedStoryIds`, `affectedPbiIds`, `affectedTaskIds`, `conflicts`
+- `actions/commit-sprint-membership.test.ts`:
+   - Race-conditie: story die ondertussen in andere sprint zit, eindigt in conflicts en wordt niet ge-update
+   - Removes met onverwachte sprint_id (al verwijderd) eindigen in `conflicts.alreadyRemoved`
+- `lib/active-sprint.test.ts`:
+   - Key+null → return null (geen fallback)
+   - Key+string → die sprint (mits gevonden)
+   - Key ontbreekt → fallback-cascade actief
+- `lib/user-settings.test.ts`:
+   - Zod-schema accepteert nullable values in `activeSprints`
+   - `pendingSprintDraft` met per-PBI overrides round-trippt
+- `actions/active-sprint.test.ts`:
+   - `clearActiveSprintAction` schrijft `null`, **delete niet** de key — assert dat key blijft bestaan met null-value
+- Endpoint-tests voor de twee nieuwe route handlers:
+   - `sprint-membership-summary` zonder `pbiIds`-param → 400
+   - `cross-sprint-blocks` zonder `pbiIds`-param → 400
+- **Initial render doet géén story/task query** — assert via mock dat alleen `getProductBacklogPbis(_, _, 'matching')` is aangeroepen
+- **A′ start doet géén brede story-ID query** — assert dat geen call met product-wide scope uitgaat; per-PBI overrides cleanup werkt zonder fetch
+
+### Code-validatie
+
+```bash
+npm run verify && npm run build
+```
+
+---
+
+## Reactie op review
+
+### Eerste review
+
+| Review-punt | Hoe geadresseerd |
+|---|---|
+| **P1 — Initial summary kan te zwaar worden** | Geen counts in initial render. Bestaande `getProductBacklogPbis(_, _, 'matching')` blijft. Counts apart via lazy summary-endpoint, alleen in state B, gescoped op `pbiIds`. |
+| **P1 — `getStoryIdsByPbi(productId)` breekt lazy-loading** | Verwijderd. Hergebruik `ensurePbiLoaded` lazy per PBI. Pending draft-state is compact (per-PBI `pbiIntent` + per-PBI `storyOverrides`), niet alle story-IDs. |
+| **P1 — "Page herhydrateert" introduceert dure refresh** | Server actions retourneren `affectedStoryIds`/`affectedPbiIds`/`affectedTaskIds`. Client patcht workspace-store gericht. Geen `router.refresh()`. |
+| **P1 — `Sprint afsluiten` mag completion-semantiek niet overslaan** | `closeSprintAction` geschrapt. SprintEditDialog doet alleen metadata. Sprint-afronden gaat via bestaande `completeSprintAction` op sprint-page; SprintEditDialog krijgt link daarheen. |
+| **P2 — "Geen actieve sprint"-contract** | Schema nullable: `activeSprints[productId]: string \| null`. Sleutel-aanwezigheid heeft betekenis (key ontbreekt = fallback; key=null = bewust geen). `clearActiveSprintInSettings` schrijft null. |
+| **P2 — Cache Components vs huidige stijl** | Beslist: blijven bij route handlers + `cache: 'no-store'` + `revalidatePath`. Géén `'use cache'`/`cacheTag` in dit plan. |
+| **P2 — Bestaande PBI-selectieflow** | Ombouwen naar A′-mode. Eén flow, geen feature-flag-parallellisme. `createSprintWithPbisAction` wordt `createSprintWithSelectionAction`. |
+| **P2 — Store moet primitives bewaren** | `pbiSummary` slaat alleen `totalStoryCount`/`inActiveSprintStoryCount` op. Tri-state is een selector. `sprintMembershipPending` gebruikt arrays, geen Sets. |
+| **P2 — Filter-first/background-remaining ontbreekt** | Expliciet opgenomen: initial = matching, background = remaining via bestaand route-handler-patroon. |
+| **Tests die review zou toevoegen** | Allemaal opgenomen in test-sectie hierboven. |
+
+### Tweede review (deze ronde)
+
+| Punt | Hoe geadresseerd |
+|---|---|
+| **P1 — `story.status` bij membership-mutaties** | Add: `sprint_id=X` **én** `status='IN_SPRINT'`. Remove: `sprint_id=NULL` **én** `status='OPEN'`. Task.sprint_id mee in **dezelfde transactie**. Expliciet in pseudocode van `commitSprintMembershipAction` en `createSprintWithSelectionAction`. |
+| **P1 — Eligibility voor toevoegen** | Server-resolve filtert vóór mutatie: alleen stories met `sprint_id IS NULL` **en** `status != 'DONE'`. Niet-eligible → `conflicts.notEligible[]` in return, toast op client. Stories uit CLOSED/ARCHIVED/FAILED sprints met DONE-status zijn dus geblokkeerd. |
+| **P1 — A′ draft-shape moet per-PBI** | `storyOverrides` herstructureerd naar `{ [pbiId]: { add, remove } }`. Cleanup bij PBI-toggle is lokaal; restore is deterministisch zonder brede story-fetch. |
+| **P1 — Endpoint scoping** | `sprint-membership-summary` en `cross-sprint-blocks` vereisen verplichte `pbiIds`-query-parameter. Server weigert product-brede aanroepen. |
+| **P2 — `lib/user-settings.ts` expliciet** | Opgenomen in critical files. Zod-schema wijzigt: `activeSprints` nullable; `pendingSprintDraft` als optionele key. |
+| **P2 — `clearActiveSprintInSettings`-semantiek** | Schrijft nu `null` i.p.v. key te `delete`. Onderscheid: key ontbreekt = fallback; key=null = bewust geen actieve sprint. |
+| **P2 — Context-tekst stale** | Context-sectie herschreven: lazy-load-basis bestaat al; dit plan bouwt erop voort. |
+
+---
+
+## Volgende stap (na goedkeuring)
+
+Per project-memory: PBI + stories + taken aanmaken via Scrum4Me-MCP, daarna implementatieplan koppelen, taken pas uitvoeren op verzoek.
+
+Werk-splitsing (laag-voor-laag, met dataflow eerst maar zonder onnodige eager loads):
+
+1. **Story 1 — Active-sprint null-contract** + `clearActiveSprintAction` + `resolveActiveSprint`-aanpassing + sprint-switcher uitbreiding ("— Geen actieve sprint —"-optie)
+2. **Story 2 — User-settings draft-slot** + `setPendingSprintDraftAction` / `clearPendingSprintDraftAction` (compacte intent-shape)
+3. **Story 3 — Sprint-membership-summary endpoint** + `crossSprintBlocks` endpoint + store-uitbreidingen (`pbiSummary`, `loadedStoryIdsByPbi`, `crossSprintBlocks`)
+4. **Story 4 — State B pending-buffer-slice** (arrays) + selectors voor tri-state + `selectStoryEffectiveInSprint` / `selectStoryIsBlocked`
+5. **Story 5 — A′ UI** (metadata-modal + sticky banner) + ombouw `selectionMode` in `PbiList` + persistente draft-restore
+6. **Story 6 — State B vinkjes-UI** (PBI tri-state, story binair, disabled-bij-conflict) + "Sprint opslaan"-knop met teller
+7. **Story 7 — `createSprintWithSelectionAction`** (uitbreiding van bestaande `createSprintWithPbisAction`) + server-side intent-resolve + cross-sprint guard + return-affected-IDs
+8. **Story 8 — `commitSprintMembershipAction`** + cross-sprint guard + gerichte client-store patches + SSE-broadcast
+9. **Story 9 — SprintEditDialog** (metadata) + `updateSprintAction` + link naar afrondings-flow
+10. **Story 10 — Multi-OPEN sprints** (drop uniqueness-check in `createSprintAction`)
+11. **Story 11 — Verificatie + tests** (Vitest + handmatige checklist)

lib/active-sprint.ts

@@ -40,12 +40,20 @@ async function notifyUserSettings(
   `
 }
 
-export async function getActiveSprintIdFromSettings(
-  userId: string,
+type StoredActiveSprintState =
+  | { kind: 'unset' }
+  | { kind: 'cleared' }
+  | { kind: 'set'; sprintId: string }
+
+export function readStoredActiveSprintState(
+  settings: UserSettings,
   productId: string,
-): Promise<string | null> {
-  const settings = await readSettings(userId)
-  return settings.layout?.activeSprints?.[productId] ?? null
+): StoredActiveSprintState {
+  const map = settings.layout?.activeSprints
+  if (!map || !(productId in map)) return { kind: 'unset' }
+  const value = map[productId]
+  if (value === null) return { kind: 'cleared' }
+  return { kind: 'set', sprintId: value }
 }
 
 export async function setActiveSprintInSettings(
@@ -71,10 +79,10 @@ export async function clearActiveSprintInSettings(
   productId: string,
 ): Promise<void> {
   const current = await readSettings(userId)
-  const existing = current.layout?.activeSprints
-  if (!existing || !(productId in existing)) return
-  const nextActiveSprints = { ...existing }
-  delete nextActiveSprints[productId]
+  const nextActiveSprints: Record<string, string | null> = {
+    ...(current.layout?.activeSprints ?? {}),
+    [productId]: null,
+  }
   const next: UserSettings = {
     ...current,
     layout: { ...current.layout, activeSprints: nextActiveSprints },
@@ -85,14 +93,69 @@ export async function clearActiveSprintInSettings(
   })
 }
 
+/**
+ * PBI-79: persisteer sprint-keuze + bijbehorende PBI/story-selectie atomair.
+ * Sprintkeuze blijft 'sleutel met null = bewust geen sprint'-contract trouw;
+ * activePbi/activeStory volgen dezelfde semantiek (null = expliciet leeg).
+ */
+export async function setActiveSelectionInSettings(
+  userId: string,
+  productId: string,
+  selection: {
+    sprintId: string | null
+    pbiId?: string | null
+    storyId?: string | null
+  },
+): Promise<void> {
+  const current = await readSettings(userId)
+  const nextActiveSprints: Record<string, string | null> = {
+    ...(current.layout?.activeSprints ?? {}),
+    [productId]: selection.sprintId,
+  }
+  const nextActivePbis: Record<string, string | null> = {
+    ...(current.layout?.activePbis ?? {}),
+  }
+  if (selection.pbiId !== undefined) {
+    nextActivePbis[productId] = selection.pbiId
+  }
+  const nextActiveStories: Record<string, string | null> = {
+    ...(current.layout?.activeStories ?? {}),
+  }
+  if (selection.storyId !== undefined) {
+    nextActiveStories[productId] = selection.storyId
+  }
+
+  const next: UserSettings = {
+    ...current,
+    layout: {
+      ...current.layout,
+      activeSprints: nextActiveSprints,
+      activePbis: nextActivePbis,
+      activeStories: nextActiveStories,
+    },
+  }
+  await writeSettings(userId, next)
+  await notifyUserSettings(userId, {
+    layout: {
+      activeSprints: nextActiveSprints,
+      activePbis: nextActivePbis,
+      activeStories: nextActiveStories,
+    },
+  })
+}
+
 export async function resolveActiveSprint(
   productId: string,
   userId: string,
 ): Promise<ActiveSprint | null> {
-  const stored = await getActiveSprintIdFromSettings(userId, productId)
-  if (stored) {
+  const settings = await readSettings(userId)
+  const state = readStoredActiveSprintState(settings, productId)
+
+  if (state.kind === 'cleared') return null
+
+  if (state.kind === 'set') {
     const sprint = await prisma.sprint.findFirst({
-      where: { id: stored, product_id: productId },
+      where: { id: state.sprintId, product_id: productId },
       select: { id: true, code: true, status: true },
     })
     if (sprint) return sprint

lib/sprint-conflicts.ts

@@ -0,0 +1,116 @@
+import type { Prisma, PrismaClient, StoryStatus } from '@prisma/client'
+
+export type EligibilityReason = 'DONE' | 'IN_OTHER_SPRINT'
+
+export type CrossSprintBlock = {
+  storyId: string
+  sprintId: string
+  sprintName: string
+}
+
+export type EligibilityPartition = {
+  eligible: string[]
+  notEligible: { storyId: string; reason: EligibilityReason }[]
+  crossSprint: CrossSprintBlock[]
+}
+
+type StoryEligibilityInput = {
+  sprint_id: string | null
+  status: StoryStatus
+}
+
+export function isEligibleForSprint(story: StoryEligibilityInput): boolean {
+  return story.sprint_id === null && story.status !== 'DONE'
+}
+
+type PrismaLike = Pick<PrismaClient, 'story'> | Prisma.TransactionClient
+
+export async function partitionByEligibility(
+  prisma: PrismaLike,
+  storyIds: string[],
+  excludeSprintId?: string,
+): Promise<EligibilityPartition> {
+  if (storyIds.length === 0) {
+    return { eligible: [], notEligible: [], crossSprint: [] }
+  }
+
+  const stories = await prisma.story.findMany({
+    where: { id: { in: storyIds } },
+    select: {
+      id: true,
+      sprint_id: true,
+      status: true,
+      sprint: { select: { id: true, code: true, status: true } },
+    },
+  })
+
+  const eligible: string[] = []
+  const notEligible: { storyId: string; reason: EligibilityReason }[] = []
+  const crossSprint: CrossSprintBlock[] = []
+
+  for (const story of stories) {
+    const inOtherSprint = story.sprint_id !== null && story.sprint_id !== excludeSprintId
+    const inSameSprint = excludeSprintId !== undefined && story.sprint_id === excludeSprintId
+
+    if (inOtherSprint) {
+      if (story.sprint && story.sprint.status === 'OPEN') {
+        crossSprint.push({
+          storyId: story.id,
+          sprintId: story.sprint.id,
+          sprintName: story.sprint.code,
+        })
+      }
+      notEligible.push({ storyId: story.id, reason: 'IN_OTHER_SPRINT' })
+      continue
+    }
+
+    if (story.status === 'DONE') {
+      notEligible.push({ storyId: story.id, reason: 'DONE' })
+      continue
+    }
+
+    if (inSameSprint) {
+      eligible.push(story.id)
+      continue
+    }
+
+    eligible.push(story.id)
+  }
+
+  return { eligible, notEligible, crossSprint }
+}
+
+export async function getBlockingSprintMap(
+  prisma: PrismaLike,
+  productId: string,
+  storyIds: string[],
+  excludeSprintId?: string,
+): Promise<Map<string, { sprintId: string; sprintName: string }>> {
+  const out = new Map<string, { sprintId: string; sprintName: string }>()
+  if (storyIds.length === 0) return out
+
+  const stories = await prisma.story.findMany({
+    where: {
+      id: { in: storyIds },
+      product_id: productId,
+      sprint_id: { not: null },
+      sprint: { status: 'OPEN' },
+    },
+    select: {
+      id: true,
+      sprint_id: true,
+      sprint: { select: { id: true, code: true, status: true } },
+    },
+  })
+
+  for (const story of stories) {
+    if (!story.sprint) continue
+    if (excludeSprintId !== undefined && story.sprint.id === excludeSprintId) continue
+    out.set(story.id, {
+      sprintId: story.sprint.id,
+      sprintName: story.sprint.code,
+    })
+  }
+
+  return out
+}

lib/user-settings.ts

@@ -45,16 +45,41 @@ const DevToolsPrefs = z.object({
 
 const LayoutPrefs = z.object({
   splitPanePositions: z.record(z.string(), z.array(z.number())).optional(),
-  activeSprints: z.record(z.string(), z.string()).optional(),
+  activeSprints: z.record(z.string(), z.string().nullable()).optional(),
+  activePbis: z.record(z.string(), z.string().nullable()).optional(),
+  activeStories: z.record(z.string(), z.string().nullable()).optional(),
+}).strict()
+
+const PbiIntent = z.enum(['all', 'none'])
+
+const StoryOverrides = z.object({
+  add: z.array(z.string()),
+  remove: z.array(z.string()),
+}).strict()
+
+const PendingSprintDraftSchema = z.object({
+  goal: z.string().min(1),
+  startAt: z.string().date().optional(),
+  endAt: z.string().date().optional(),
+  pbiIntent: z.record(z.string(), PbiIntent).default({}),
+  storyOverrides: z.record(z.string(), StoryOverrides).default({}),
+}).strict()
+
+const WorkflowPrefs = z.object({
+  pendingSprintDraft: z.record(z.string(), PendingSprintDraftSchema).optional(),
 }).strict()
 
 export const UserSettingsSchema = z.object({
   views: ViewsPrefs.optional(),
   devTools: DevToolsPrefs.optional(),
   layout: LayoutPrefs.optional(),
+  workflow: WorkflowPrefs.optional(),
 }).strict()
 
 export type UserSettings = z.infer<typeof UserSettingsSchema>
+export type PendingSprintDraft = z.infer<typeof PendingSprintDraftSchema>
+export type PbiIntent = z.infer<typeof PbiIntent>
+export type StoryOverrides = z.infer<typeof StoryOverrides>
 
 export const DEFAULT_USER_SETTINGS: UserSettings = {}
 

stores/product-workspace/selectors.ts

@@ -1,5 +1,13 @@
 import type { ProductWorkspaceStore } from './store'
-import type { BacklogPbi, BacklogStory, BacklogTask, TaskDetail } from './types'
+import type {
+  BacklogPbi,
+  BacklogStory,
+  BacklogTask,
+  CrossSprintBlock,
+  TaskDetail,
+} from './types'
+
+export type PbiTriState = 'empty' | 'partial' | 'full'
 
 // G1: stable EMPTY-references zodat selectors geen nieuwe array per call retourneren.
 const EMPTY_PBIS: BacklogPbi[] = []
@@ -100,3 +108,72 @@ export function selectStoriesForPbi(
   }
   return out.length === 0 ? EMPTY_STORIES : out
 }
+
+// PBI-79 / ST-1336 — sprint-membership selectors.
+//
+// Tri-state PBI-vinkje. Werkt op counts uit het summary-endpoint zolang
+// de PBI dichtgeklapt is (relations.storyIdsByPbi leeg). Wanneer stories
+// geladen zijn rekenen we ook de pending-buffer mee per-story.
+export function selectPbiTriState(
+  s: ProductWorkspaceStore,
+  pbiId: string,
+): PbiTriState {
+  const summary = s.sprintMembership.pbiSummary[pbiId]
+  if (!summary || summary.totalStoryCount === 0) return 'empty'
+
+  const storyIds = s.relations.storyIdsByPbi[pbiId]
+  let inSprintAfterPending = summary.inActiveSprintStoryCount
+
+  if (storyIds && storyIds.length > 0) {
+    const idSet = new Set(storyIds)
+    const adds = s.sprintMembership.pending.adds
+    const removes = s.sprintMembership.pending.removes
+    for (const id of adds) if (idSet.has(id)) inSprintAfterPending++
+    for (const id of removes) if (idSet.has(id)) inSprintAfterPending--
+  }
+
+  if (inSprintAfterPending <= 0) return 'empty'
+  if (inSprintAfterPending >= summary.totalStoryCount) return 'full'
+  return 'partial'
+}
+
+/**
+ * Effectief membership van een story rekening houdend met de pending buffer.
+ * `activeSprintId` is de gekozen sprint (state B); zonder die context valt de
+ * selector terug op de DB-waarde.
+ */
+export function selectStoryEffectiveInSprint(
+  s: ProductWorkspaceStore,
+  storyId: string,
+  activeSprintId: string | null,
+): boolean {
+  const story = s.entities.storiesById[storyId]
+  const inSprintDb = story?.sprint_id === activeSprintId && activeSprintId !== null
+  const inAdds = s.sprintMembership.pending.adds.includes(storyId)
+  const inRemoves = s.sprintMembership.pending.removes.includes(storyId)
+  if (inAdds) return true
+  if (inRemoves) return false
+  return inSprintDb
+}
+
+export function selectStoryIsBlocked(
+  s: ProductWorkspaceStore,
+  storyId: string,
+): CrossSprintBlock | null {
+  return s.sprintMembership.crossSprintBlocks[storyId] ?? null
+}
+
+export function selectIsDirty(s: ProductWorkspaceStore): boolean {
+  return (
+    s.sprintMembership.pending.adds.length +
+      s.sprintMembership.pending.removes.length >
+    0
+  )
+}
+
+export function selectPendingCount(s: ProductWorkspaceStore): number {
+  return (
+    s.sprintMembership.pending.adds.length +
+    s.sprintMembership.pending.removes.length
+  )
+}

stores/product-workspace/store.ts

@@ -7,12 +7,15 @@ import {
   type BacklogPbi,
   type BacklogStory,
   type BacklogTask,
+  type CrossSprintBlock,
   type OptimisticMutation,
+  type PbiSummaryEntry,
   type PendingOptimisticMutation,
   type ProductBacklogSnapshot,
   type ProductRealtimeEvent,
   type RealtimeStatus,
   type ResyncReason,
+  type SprintMembershipSlice,
   type TaskDetail,
 } from './types'
 import {
@@ -73,6 +76,7 @@ interface State {
   loading: LoadingSlice
   sync: SyncSlice
   pendingMutations: Record<string, PendingOptimisticMutation>
+  sprintMembership: SprintMembershipSlice
 }
 
 interface Actions {
@@ -100,6 +104,31 @@ interface Actions {
   settleMutation(mutationId: string): void
 
   setRealtimeStatus(status: RealtimeStatus): void
+
+  // PBI-79 / ST-1336: sprint-membership acties.
+  setPbiSummary(summary: Record<string, PbiSummaryEntry>): void
+  setCrossSprintBlocks(blocks: Record<string, CrossSprintBlock>): void
+  toggleStorySprintMembership(storyId: string, currentlyInSprint: boolean): void
+  resetSprintMembershipPending(): void
+  fetchSprintMembershipSummary(
+    productId: string,
+    sprintId: string,
+    pbiIds: string[],
+  ): Promise<void>
+  fetchCrossSprintBlocks(
+    productId: string,
+    excludeSprintId: string | null,
+    pbiIds: string[],
+  ): Promise<void>
+
+  // PBI-79 / ST-1340: gericht patchen na server-action commit. Tasks in
+  // de client-store hebben geen sprint_id-veld dus alleen story-records
+  // worden gemuteerd.
+  applyMembershipCommitResult(input: {
+    activeSprintId: string
+    addedStoryIds: string[]
+    removedStoryIds: string[]
+  }): void
 }
 
 export type ProductWorkspaceStore = State & Actions
@@ -136,6 +165,12 @@ const initialState: State = {
     resyncReason: null,
   },
   pendingMutations: {},
+  sprintMembership: {
+    pbiSummary: {},
+    crossSprintBlocks: {},
+    pending: { adds: [], removes: [] },
+    loadedSummaryForSprintId: null,
+  },
 }
 
 function comparePbi(a: BacklogPbi, b: BacklogPbi): number {
@@ -194,6 +229,12 @@ export const useProductWorkspaceStore = create<ProductWorkspaceStore>()(
         s.entities.storiesById = {}
         s.entities.tasksById = {}
         s.relations.pbiIds = []
+        s.sprintMembership = {
+          pbiSummary: {},
+          crossSprintBlocks: {},
+          pending: { adds: [], removes: [] },
+          loadedSummaryForSprintId: null,
+        }
         s.relations.storyIdsByPbi = {}
         s.relations.taskIdsByStory = {}
 
@@ -293,10 +334,15 @@ export const useProductWorkspaceStore = create<ProductWorkspaceStore>()(
           await get().ensurePbiLoaded(pbiId, requestId)
           if (get().loading.activeRequestId !== requestId) return
           if (!productId) return
-          // T-857: cascade-restore
+          // T-857: cascade-restore. Alleen herstellen als de hint-story
+          // bij de nieuw-geselecteerde PBI hoort — anders blijft een task-
+          // selectie van een vorige PBI hangen (PBI-79 bugfix).
           const hint = readHints().perProduct[productId]?.lastActiveStoryId
-          if (hint && get().entities.storiesById[hint]) {
-            get().setActiveStory(hint)
+          if (hint) {
+            const hintStory = get().entities.storiesById[hint]
+            if (hintStory && hintStory.pbi_id === pbiId) {
+              get().setActiveStory(hint)
+            }
           }
         })()
       }
@@ -566,6 +612,102 @@ export const useProductWorkspaceStore = create<ProductWorkspaceStore>()(
         s.sync.realtimeStatus = status
       })
     },
+
+    setPbiSummary(summary) {
+      set((s) => {
+        s.sprintMembership.pbiSummary = summary
+      })
+    },
+
+    setCrossSprintBlocks(blocks) {
+      set((s) => {
+        s.sprintMembership.crossSprintBlocks = blocks
+      })
+    },
+
+    toggleStorySprintMembership(storyId, currentlyInSprint) {
+      set((s) => {
+        const pending = s.sprintMembership.pending
+        if (currentlyInSprint) {
+          const inRemoves = pending.removes.indexOf(storyId)
+          if (inRemoves >= 0) {
+            pending.removes.splice(inRemoves, 1)
+          } else {
+            const inAdds = pending.adds.indexOf(storyId)
+            if (inAdds >= 0) pending.adds.splice(inAdds, 1)
+            pending.removes.push(storyId)
+          }
+        } else {
+          const inAdds = pending.adds.indexOf(storyId)
+          if (inAdds >= 0) {
+            pending.adds.splice(inAdds, 1)
+          } else {
+            const inRemoves = pending.removes.indexOf(storyId)
+            if (inRemoves >= 0) pending.removes.splice(inRemoves, 1)
+            pending.adds.push(storyId)
+          }
+        }
+      })
+    },
+
+    resetSprintMembershipPending() {
+      set((s) => {
+        s.sprintMembership.pending = { adds: [], removes: [] }
+      })
+    },
+
+    async fetchSprintMembershipSummary(productId, sprintId, pbiIds) {
+      if (pbiIds.length === 0) return
+      const url = `/api/products/${productId}/sprint-membership-summary?sprintId=${encodeURIComponent(sprintId)}&pbiIds=${pbiIds.map(encodeURIComponent).join(',')}`
+      const summary = await fetchJson<Record<string, PbiSummaryEntry>>(url)
+      set((s) => {
+        for (const [pbiId, entry] of Object.entries(summary)) {
+          s.sprintMembership.pbiSummary[pbiId] = entry
+        }
+        s.sprintMembership.loadedSummaryForSprintId = sprintId
+      })
+    },
+
+    async fetchCrossSprintBlocks(productId, excludeSprintId, pbiIds) {
+      if (pbiIds.length === 0) return
+      const params = new URLSearchParams()
+      if (excludeSprintId) params.set('excludeSprintId', excludeSprintId)
+      params.set('pbiIds', pbiIds.join(','))
+      const url = `/api/products/${productId}/cross-sprint-blocks?${params.toString()}`
+      const blocks = await fetchJson<Record<string, CrossSprintBlock>>(url)
+      set((s) => {
+        for (const [storyId, info] of Object.entries(blocks)) {
+          s.sprintMembership.crossSprintBlocks[storyId] = info
+        }
+      })
+    },
+
+    applyMembershipCommitResult({
+      activeSprintId,
+      addedStoryIds,
+      removedStoryIds,
+    }) {
+      // Task-records in de client-store hebben geen sprint_id-veld (alleen
+      // story_id); de sprint-membership wordt afgeleid via story.sprint_id.
+      // Hier patchen we daarom alleen story-entities + de pending buffer.
+      set((s) => {
+        for (const id of addedStoryIds) {
+          const story = s.entities.storiesById[id]
+          if (story) {
+            story.sprint_id = activeSprintId
+            story.status = 'IN_SPRINT'
+          }
+        }
+        for (const id of removedStoryIds) {
+          const story = s.entities.storiesById[id]
+          if (story) {
+            story.sprint_id = null
+            story.status = 'OPEN'
+          }
+        }
+        s.sprintMembership.pending = { adds: [], removes: [] }
+      })
+    },
   })),
 )
 

stores/product-workspace/types.ts

@@ -138,3 +138,21 @@ export interface PendingOptimisticMutation {
   mutation: OptimisticMutation
   createdAt: number
 }
+
+// PBI-79 / ST-1336: sprint-membership state voor backlog-page.
+export interface PbiSummaryEntry {
+  totalStoryCount: number
+  inActiveSprintStoryCount: number
+}
+
+export interface CrossSprintBlock {
+  sprintId: string
+  sprintName: string
+}
+
+export interface SprintMembershipSlice {
+  pbiSummary: Record<string, PbiSummaryEntry>
+  crossSprintBlocks: Record<string, CrossSprintBlock>
+  pending: { adds: string[]; removes: string[] }
+  loadedSummaryForSprintId: string | null
+}

stores/user-settings/store.ts

@@ -4,6 +4,8 @@ import { immer } from 'zustand/middleware/immer'
 import {
   DEFAULT_USER_SETTINGS,
   mergeSettings,
+  type PbiIntent,
+  type PendingSprintDraft,
   type UserSettings,
 } from '@/lib/user-settings'
 import { updateUserSettingsAction } from '@/actions/user-settings'
@@ -28,6 +30,22 @@ interface UserSettingsActions {
   hydrate: (initial: UserSettings, isDemo: boolean) => void
   setPref: (path: SettingsPath, value: unknown) => Promise<void>
   applyServerPatch: (patch: Partial<UserSettings>) => void
+  setPendingSprintDraft: (
+    productId: string,
+    draft: PendingSprintDraft,
+  ) => Promise<void>
+  clearPendingSprintDraft: (productId: string) => Promise<void>
+  upsertPbiIntent: (
+    productId: string,
+    pbiId: string,
+    intent: PbiIntent,
+  ) => Promise<void>
+  upsertStoryOverride: (
+    productId: string,
+    pbiId: string,
+    storyId: string,
+    kind: 'add' | 'remove' | 'clear',
+  ) => Promise<void>
 }
 
 let nextMutationId = 1
@@ -58,7 +76,15 @@ export const useUserSettingsStore = create<UserSettingsState & UserSettingsActio
 
     hydrate: (initial, isDemo) => {
       set((draft) => {
-        draft.entities.settings = initial as UserSettings
+        // PBI-79 scope-aanpassing: pendingSprintDraft is session-only;
+        // eventuele legacy DB-entries van vóór deze aanpassing worden bij
+        // hydratatie weggegooid zodat de draft niet 'spookt'.
+        const stripped: UserSettings = { ...initial }
+        if (stripped.workflow?.pendingSprintDraft) {
+          stripped.workflow = { ...stripped.workflow }
+          delete stripped.workflow.pendingSprintDraft
+        }
+        draft.entities.settings = stripped
         draft.context.hydrated = true
         draft.context.isDemo = isDemo
       })
@@ -73,6 +99,79 @@ export const useUserSettingsStore = create<UserSettingsState & UserSettingsActio
       })
     },
 
+    setPendingSprintDraft: async (productId, draft) => {
+      // PBI-79 scope-aanpassing: session-only. Geen server-roundtrip;
+      // de draft leeft uitsluitend in deze store-instantie en is bij
+      // page-refresh/leave weg (zie SprintDraftLeaveGuard voor de
+      // beforeunload-warning).
+      set((s) => {
+        if (!s.entities.settings.workflow) s.entities.settings.workflow = {}
+        if (!s.entities.settings.workflow.pendingSprintDraft) {
+          s.entities.settings.workflow.pendingSprintDraft = {}
+        }
+        s.entities.settings.workflow.pendingSprintDraft[productId] = draft
+      })
+    },
+
+    clearPendingSprintDraft: async (productId) => {
+      // PBI-79 scope-aanpassing: session-only — lokale delete is voldoende.
+      set((s) => {
+        const map = s.entities.settings.workflow?.pendingSprintDraft
+        if (map) delete map[productId]
+      })
+    },
+
+    upsertPbiIntent: async (productId, pbiId, intent) => {
+      const current =
+        get().entities.settings.workflow?.pendingSprintDraft?.[productId]
+      if (!current) return
+      const nextOverrides = { ...current.storyOverrides }
+      delete nextOverrides[pbiId]
+      const next: PendingSprintDraft = {
+        ...current,
+        pbiIntent: { ...current.pbiIntent, [pbiId]: intent },
+        storyOverrides: nextOverrides,
+      }
+      await get().setPendingSprintDraft(productId, next)
+    },
+
+    upsertStoryOverride: async (productId, pbiId, storyId, kind) => {
+      const current =
+        get().entities.settings.workflow?.pendingSprintDraft?.[productId]
+      if (!current) return
+      const existing = current.storyOverrides[pbiId] ?? { add: [], remove: [] }
+      const dropFrom = (arr: string[]) => arr.filter((id) => id !== storyId)
+      let nextEntry: { add: string[]; remove: string[] }
+      switch (kind) {
+        case 'add':
+          nextEntry = {
+            add: existing.add.includes(storyId) ? existing.add : [...existing.add, storyId],
+            remove: dropFrom(existing.remove),
+          }
+          break
+        case 'remove':
+          nextEntry = {
+            add: dropFrom(existing.add),
+            remove: existing.remove.includes(storyId)
+              ? existing.remove
+              : [...existing.remove, storyId],
+          }
+          break
+        case 'clear':
+        default:
+          nextEntry = { add: dropFrom(existing.add), remove: dropFrom(existing.remove) }
+          break
+      }
+      const nextOverrides = { ...current.storyOverrides }
+      if (nextEntry.add.length === 0 && nextEntry.remove.length === 0) {
+        delete nextOverrides[pbiId]
+      } else {
+        nextOverrides[pbiId] = nextEntry
+      }
+      const next: PendingSprintDraft = { ...current, storyOverrides: nextOverrides }
+      await get().setPendingSprintDraft(productId, next)
+    },
+
     setPref: async (path, value) => {
       const patch = patchFromPath(path, value)