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

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

    const song = await prisma.song.findUnique({
      where: { id },
      include: {
        artist: {
          select: {
            id: true,
            name: true,
            slug: true,
            avatarUrl: true,
            verified: true,
          },
        },
        album: {
          select: {
            id: true,
            title: true,
            slug: true,
            coverUrl: true,
          },
        },
        genres: {
          include: {
            genre: true,
          },
        },
      },
    })

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

    // Only allow private songs to be viewed by the artist
    if (!song.isPublic && (!user || !user.artist || user.artist.id !== song.artistId)) {
      return NextResponse.json({ error: 'Song not found' }, { status: 404 })
    }

    return NextResponse.json(song)
  } catch (error) {
    console.error('Error fetching song:', error)
    return NextResponse.json({ error: 'Failed to fetch song' }, { status: 500 })
  }
}

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

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

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

    if (existingSong.artistId !== artist.id) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 403 })
    }

    const body = await request.json()
    const {
      title,
      description,
      coverUrl,
      albumId,
      genreIds,
      isPublic,
    } = body

    const updateData: any = {}
    if (title !== undefined) {
      updateData.title = title
      updateData.slug = slugify(title)
    }
    if (description !== undefined) updateData.description = description
    if (coverUrl !== undefined) updateData.coverUrl = coverUrl
    if (albumId !== undefined) updateData.albumId = albumId
    if (isPublic !== undefined) updateData.isPublic = isPublic

    // Handle genre updates separately
    if (genreIds !== undefined) {
      await prisma.songGenre.deleteMany({
        where: { songId: id },
      })
      if (genreIds.length > 0) {
        await prisma.songGenre.createMany({
          data: genreIds.map((genreId: string) => ({
            songId: id,
            genreId,
          })),
        })
      }
    }

    const updatedSong = await prisma.song.update({
      where: { id },
      data: updateData,
      include: {
        artist: {
          select: {
            id: true,
            name: true,
            slug: true,
            avatarUrl: true,
            verified: true,
          },
        },
        album: {
          select: {
            id: true,
            title: true,
            slug: true,
            coverUrl: true,
          },
        },
        genres: {
          include: {
            genre: true,
          },
        },
      },
    })

    return NextResponse.json(updatedSong)
  } catch (error) {
    if (error instanceof Error && error.message === 'Unauthorized') {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
    }
    if (error instanceof Error && error.message === 'Artist profile required') {
      return NextResponse.json({ error: 'Artist profile required' }, { status: 403 })
    }
    console.error('Error updating song:', error)
    return NextResponse.json({ error: 'Failed to update song' }, { status: 500 })
  }
}

export async function DELETE(
  request: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  try {
    const { artist } = await requireArtist()
    const { id } = await params

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

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

    if (existingSong.artistId !== artist.id) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 403 })
    }

    await prisma.song.delete({
      where: { id },
    })

    return NextResponse.json({ message: 'Song deleted successfully' })
  } catch (error) {
    if (error instanceof Error && error.message === 'Unauthorized') {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
    }
    if (error instanceof Error && error.message === 'Artist profile required') {
      return NextResponse.json({ error: 'Artist profile required' }, { status: 403 })
    }
    console.error('Error deleting song:', error)
    return NextResponse.json({ error: 'Failed to delete song' }, { status: 500 })
  }
}