import { createClient } from '@/lib/supabase/server'
import { PrismaClient } from '@prisma/client'
import { NextRequest, NextResponse } from 'next/server'

const prisma = new PrismaClient()

// POST /api/channels/follow - Follow/unfollow a channel
export async function POST(req: NextRequest) {
  const supabase = await createClient()
  const { data: { user: supabaseUser }, error: authError } = await supabase.auth.getUser()

  if (authError || !supabaseUser) {
    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
  }

  try {
    const body = await req.json()
    const { channelId, action } = body // action: 'follow' or 'unfollow'

    if (!channelId || !action) {
      return NextResponse.json(
        { error: 'Channel ID and action are required' },
        { status: 400 }
      )
    }

    // Get user
    const user = await prisma.user.findUnique({
      where: { supabaseId: supabaseUser.id },
    })

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

    if (action === 'follow') {
      // Create follower relationship
      const follower = await prisma.follower.create({
        data: {
          userId: user.id,
          channelId,
        },
      })

      return NextResponse.json(
        { message: 'Followed successfully', follower },
        { status: 201 }
      )
    } else if (action === 'unfollow') {
      // Remove follower relationship
      await prisma.follower.delete({
        where: {
          userId_channelId: {
            userId: user.id,
            channelId,
          },
        },
      })

      return NextResponse.json(
        { message: 'Unfollowed successfully' },
        { status: 200 }
      )
    } else {
      return NextResponse.json(
        { error: 'Invalid action' },
        { status: 400 }
      )
    }
  } catch (error) {
    console.error('Error following/unfollowing channel:', error)
    return NextResponse.json(
      { error: 'Failed to follow/unfollow channel' },
      { status: 500 }
    )
  }
}