import { NextRequest, NextResponse } from 'next/server'
import prisma from '@/lib/prisma'
import { auth } from '@/auth'

// POST /api/blocks/embed
// Body: { sourceNoteId, blockId, targetNoteId }
export async function POST(request: NextRequest) {
  const session = await auth()
  if (!session?.user?.id) {
    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
  }

  const body = await request.json()
  const { sourceNoteId, blockId, targetNoteId } = body

  if (!sourceNoteId || !blockId || !targetNoteId) {
    return NextResponse.json({ error: 'sourceNoteId, blockId and targetNoteId are required' }, { status: 400 })
  }

  // Verify both notes belong to the user
  const [sourceNote, targetNote] = await Promise.all([
    prisma.note.findFirst({ where: { id: sourceNoteId, userId: session.user.id } }),
    prisma.note.findFirst({ where: { id: targetNoteId, userId: session.user.id } }),
  ])

  if (!sourceNote || !targetNote) {
    return NextResponse.json({ error: 'Note not found or unauthorized' }, { status: 404 })
  }

  // Upsert — avoid duplicate refs
  const existing = await prisma.liveBlockRef.findFirst({
    where: { sourceNoteId, blockId, targetNoteId },
  })

  if (existing) {
    return NextResponse.json({ id: existing.id, created: false })
  }

  const ref = await prisma.liveBlockRef.create({
    data: { sourceNoteId, blockId, targetNoteId },
  })

  return NextResponse.json({ id: ref.id, created: true })
}