Scrum4Me/lib/realtime/use-backlog-realtime.ts
2026-04-30 17:42:32 +02:00

92 lines
2.6 KiB
TypeScript

'use client'
// ST-1115: Client hook for the backlog 3-pane SSE stream.
// Mounts in BacklogHydrationWrapper so it survives Server Action refreshes.
// Dispatches pbi/story/task change events into useBacklogStore.applyChange.
import { useEffect, useRef } from 'react'
import { useBacklogStore } from '@/stores/backlog-store'
const BACKOFF_START_MS = 1_000
const BACKOFF_MAX_MS = 30_000
type EntityPayload = {
op: 'I' | 'U' | 'D'
entity: 'pbi' | 'story' | 'task'
[key: string]: unknown
}
export function useBacklogRealtime(productId: string | null) {
const sourceRef = useRef<EventSource | null>(null)
const backoffRef = useRef<number>(BACKOFF_START_MS)
const reconnectTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
useEffect(() => {
if (!productId) return
const close = () => {
if (sourceRef.current) {
sourceRef.current.close()
sourceRef.current = null
}
if (reconnectTimerRef.current) {
clearTimeout(reconnectTimerRef.current)
reconnectTimerRef.current = null
}
}
const connect = () => {
close()
const source = new EventSource(
`/api/realtime/backlog?product_id=${encodeURIComponent(productId)}`,
)
sourceRef.current = source
source.addEventListener('ready', () => {
backoffRef.current = BACKOFF_START_MS
})
source.onmessage = (e) => {
if (!e.data) return
try {
const payload = JSON.parse(e.data) as EntityPayload
useBacklogStore
.getState()
.applyChange(payload.entity, payload.op, payload as Record<string, unknown>)
} catch (err) {
if (process.env.NODE_ENV !== 'production') {
console.error('[realtime/backlog] failed to parse event', err, e.data)
}
}
}
source.onerror = () => {
if (sourceRef.current !== source) return
close()
if (document.visibilityState === 'hidden') return
const delay = backoffRef.current
backoffRef.current = Math.min(backoffRef.current * 2, BACKOFF_MAX_MS)
reconnectTimerRef.current = setTimeout(connect, delay)
}
}
const onVisibility = () => {
if (document.visibilityState === 'hidden') {
close()
} else if (sourceRef.current === null) {
backoffRef.current = BACKOFF_START_MS
connect()
}
}
if (document.visibilityState === 'visible') {
connect()
}
document.addEventListener('visibilitychange', onVisibility)
return () => {
document.removeEventListener('visibilitychange', onVisibility)
close()
}
}, [productId])
}