import { cookies } from 'next/headers'
import { getIronSession } from 'iron-session'
import sharp from 'sharp'
import { prisma } from '@/lib/prisma'
import { SessionData, sessionOptions } from '@/lib/session'
import { enforceUserRateLimit } from '@/lib/rate-limit'

const MAX_BYTES = 12 * 1024 * 1024
const ALLOWED_TYPES = new Set(['image/jpeg', 'image/png', 'image/webp'])

async function getSession() {
  return getIronSession<SessionData>(await cookies(), sessionOptions)
}

export async function POST(request: Request) {
  const session = await getSession()
  if (!session.userId) {
    return Response.json({ error: 'Niet ingelogd' }, { status: 401 })
  }
  if (session.isDemo) {
    return Response.json({ error: 'Niet beschikbaar in demo-modus' }, { status: 403 })
  }

  const limited = enforceUserRateLimit('upload-avatar', session.userId)
  if (limited) return Response.json({ error: limited.error }, { status: 429 })

  const formData = await request.formData()
  const file = formData.get('avatar') as File | null
  if (!file || file.size === 0) {
    return Response.json({ error: 'Geen bestand ontvangen' }, { status: 400 })
  }

  if (!ALLOWED_TYPES.has(file.type)) {
    return Response.json({ error: 'Alleen JPEG, PNG en WebP zijn toegestaan' }, { status: 422 })
  }

  if (file.size > MAX_BYTES) {
    return Response.json({ error: 'Bestand is groter dan 12 MB' }, { status: 422 })
  }

  const input = Buffer.from(await file.arrayBuffer())

  const processed = await sharp(input)
    .resize(700, 700, { fit: 'inside', withoutEnlargement: true })
    .webp({ quality: 85 })
    .toBuffer()

  await prisma.user.update({
    where: { id: session.userId },
    data: { avatar_data: new Uint8Array(processed) },
  })

  return Response.json({ ok: true })
}

export async function GET() {
  const session = await getSession()
  if (!session.userId) {
    return new Response(null, { status: 401 })
  }

  const user = await prisma.user.findUnique({
    where: { id: session.userId },
    select: { avatar_data: true },
  })

  if (!user?.avatar_data) {
    return new Response(null, { status: 404 })
  }

  return new Response(user.avatar_data, {
    headers: {
      'Content-Type': 'image/webp',
      'Cache-Control': 'private, max-age=3600',
    },
  })
}
