import { NextRequest, NextResponse } from 'next/server'
import { semanticIndexingService } from '@/lib/services/semantic-indexing-service'
import { createServerSupabaseClient } from '@/lib/supabase'

export async function POST(
  req: NextRequest,
  { params }: { params: { id: string } }
) {
  try {
    const bookId = params.id
    const supabase = createServerSupabaseClient()

    // Get current user session from auth header
    const authHeader = req.headers.get('authorization')
    let user
    
    try {
      if (authHeader) {
        const { data: { user: authUser }, error: authError } = await supabase.auth.getUser(authHeader.replace('Bearer ', ''))
        if (!authError) user = authUser
      } else {
        const { data: { user: sessionUser }, error: sessionError } = await supabase.auth.getUser()
        if (!sessionError) user = sessionUser
      }
    } catch (e) {
      // Ignore auth errors
    }

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

    // Verify user has access to this book
    const { data: book } = await supabase
      .from('books')
      .select('id, title')
      .eq('id', bookId)
      .eq('user_id', user.id)
      .single()

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

    // Start indexing process (async)
    console.log(`🚀 Starting semantic indexing for book: ${book.title}`)
    
    // Don't await this - let it run in background
    semanticIndexingService.processBook(bookId)
      .then(() => {
        console.log(`✅ Completed semantic indexing for book: ${book.title}`)
      })
      .catch((error) => {
        console.error(`❌ Failed to index book ${book.title}:`, error)
      })

    return NextResponse.json({ 
      message: 'Indexing started',
      bookId,
      bookTitle: book.title 
    })
  } catch (error) {
    console.error('Start indexing error:', error)
    return NextResponse.json(
      { error: 'Failed to start indexing' },
      { status: 500 }
    )
  }
}