import { NextRequest, NextResponse } from 'next/server'
import prisma from '@/lib/prisma'
import { auth } from '@/auth'
import { documentIngestionService } from '@/lib/ai/services/document-ingestion.service'
import fs from 'fs'
import path from 'path'
import { randomUUID } from 'crypto'

export async function POST(
  request: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  const session = await auth()
  if (!session?.user?.id) {
    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
  }

  try {
    const { id: noteId } = await params

    const note = await prisma.note.findFirst({
      where: { id: noteId, userId: session.user.id, trashedAt: null },
    })
    if (!note) {
      return NextResponse.json({ error: 'Note not found' }, { status: 404 })
    }

    const formData = await request.formData()
    const file = formData.get('file') as File | null
    if (!file) {
      return NextResponse.json({ error: 'No file provided' }, { status: 400 })
    }

    if (file.size > 20 * 1024 * 1024) {
      return NextResponse.json({ error: 'File too large (max 20MB)' }, { status: 400 })
    }

    if (file.type !== 'application/pdf') {
      return NextResponse.json({ error: 'Only PDF files are supported' }, { status: 400 })
    }

    const dir = path.join(process.cwd(), 'data', 'uploads', 'attachments', noteId)
    fs.mkdirSync(dir, { recursive: true })
    const fileId = randomUUID()
    const filePath = path.join(dir, `${fileId}.pdf`)
    fs.writeFileSync(filePath, Buffer.from(await file.arrayBuffer()))

    const attachment = await prisma.noteAttachment.create({
      data: {
        noteId,
        fileName: file.name,
        fileType: file.type,
        fileSize: file.size,
        filePath,
        mimeType: file.type,
        status: 'pending',
      },
    })

    setImmediate(() => {
      documentIngestionService.ingest(attachment.id).catch((err) => {
        console.error('Document ingestion failed:', err)
      })
    })

    return NextResponse.json({ success: true, data: attachment }, { status: 201 })
  } catch (error) {
    console.error('Error uploading attachment:', error)
    return NextResponse.json({ error: 'Upload failed' }, { status: 500 })
  }
}

export async function GET(
  request: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  const session = await auth()
  if (!session?.user?.id) {
    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
  }

  try {
    const { id: noteId } = await params

    const note = await prisma.note.findFirst({
      where: { id: noteId, userId: session.user.id, trashedAt: null },
    })
    if (!note) {
      return NextResponse.json({ error: 'Note not found' }, { status: 404 })
    }

    const attachments = await prisma.noteAttachment.findMany({
      where: { noteId },
      orderBy: { createdAt: 'desc' },
      select: {
        id: true,
        fileName: true,
        fileSize: true,
        mimeType: true,
        status: true,
        pageCount: true,
        error: true,
        createdAt: true,
      },
    })

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