import { createClient } from '@/lib/supabase/server'
import { NextResponse } from 'next/server'

/**
 * GET /api/chat/sessions
 * List all chat sessions for the authenticated user
 */
export async function GET(request: Request) {
  const supabase = await createClient()

  const {
    data: { user },
  } = await supabase.auth.getUser()

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

  const { searchParams } = new URL(request.url)
  const limit = parseInt(searchParams.get('limit') || '20')
  const offset = parseInt(searchParams.get('offset') || '0')

  const { data, error, count } = await supabase
    .from('chat_sessions')
    .select('*', { count: 'exact' })
    .eq('user_id', user.id)
    .order('created_at', { ascending: false })
    .range(offset, offset + limit - 1)

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

  return NextResponse.json({ data, count })
}

/**
 * POST /api/chat/sessions
 * Create a new chat session
 */
export async function POST(request: Request) {
  const supabase = await createClient()

  const {
    data: { user },
  } = await supabase.auth.getUser()

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

  try {
    const body = await request.json()
    const { title } = body

    const { data, error } = await supabase
      .from('chat_sessions')
      .insert({
        user_id: user.id,
        title: title || null,
      })
      .select()
      .single()

    if (error) {
      console.error('Error creating session:', error)
      return NextResponse.json(
        { error: 'Failed to create session' },
        { status: 500 }
      )
    }

    return NextResponse.json({ data })
  } catch (err) {
    return NextResponse.json(
      { error: err instanceof Error ? err.message : 'Failed to create session' },
      { status: 400 }
    )
  }
}