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

export async function PUT(
  request: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  try {
    const user = await requireAuth()
    const { id } = await params

    const playlist = await prisma.playlist.findUnique({
      where: { id },
    })

    if (!playlist) {
      return NextResponse.json({ error: 'Playlist not found' }, { status: 404 })
    }

    if (playlist.userId !== user.id) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 403 })
    }

    const body = await request.json()
    const { songIds } = body

    if (!Array.isArray(songIds) || songIds.length === 0) {
      return NextResponse.json({ error: 'songIds array is required' }, { status: 400 })
    }

    // Update positions in a transaction
    await prisma.$transaction(
      songIds.map((songId: string, index: number) =>
        prisma.playlistSong.update({
          where: {
            playlistId_songId: {
              playlistId: id,
              songId,
            },
          },
          data: {
            position: index,
          },
        })
      )
    )

    const updatedPlaylist = await prisma.playlist.findUnique({
      where: { id },
      include: {
        songs: {
          include: {
            song: {
              include: {
                artist: {
                  select: {
                    id: true,
                    name: true,
                    slug: true,
                    avatarUrl: true,
                    verified: true,
                  },
                },
                album: {
                  select: {
                    id: true,
                    title: true,
                    slug: true,
                    coverUrl: true,
                  },
                },
              },
            },
          },
          orderBy: {
            position: 'asc',
          },
        },
      },
    })

    return NextResponse.json(updatedPlaylist)
  } catch (error) {
    if (error instanceof Error && error.message === 'Unauthorized') {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
    }
    console.error('Error reordering playlist:', error)
    return NextResponse.json({ error: 'Failed to reorder playlist' }, { status: 500 })
  }
}