import prisma from '@/lib/prisma'
import { documentExtractionService } from './document-extraction.service'
import { documentChunkingService } from './document-chunking.service'
import { embeddingService } from './embedding.service'

export class DocumentIngestionService {
  async ingest(attachmentId: string): Promise<void> {
    const attachment = await prisma.noteAttachment.findUnique({
      where: { id: attachmentId },
    })
    if (!attachment) throw new Error('Attachment not found')

    await prisma.noteAttachment.update({
      where: { id: attachmentId },
      data: { status: 'processing' },
    })

    try {
      const extracted = await documentExtractionService.extractPdf(attachment.filePath)

      await prisma.noteAttachment.update({
        where: { id: attachmentId },
        data: { pageCount: extracted.totalPages },
      })

      const chunkInputs = extracted.pages.map(p => ({
        text: p.text,
        pageNumber: p.pageNumber,
      }))
      const chunks = documentChunkingService.chunk(chunkInputs)

      const created = await Promise.all(
        chunks.map(c =>
          prisma.documentChunk.create({
            data: {
              attachmentId,
              content: c.content,
              chunkIndex: c.chunkIndex,
              pageNumber: c.pageNumber,
              startChar: c.startChar,
              endChar: c.endChar,
              metadata: c.metadata,
            },
          })
        )
      )

      const BATCH_SIZE = 20
      for (let i = 0; i < created.length; i += BATCH_SIZE) {
        const batch = created.slice(i, i + BATCH_SIZE)
        const texts = batch.map(c => c.content)
        const embeddings = await embeddingService.generateBatchEmbeddings(texts)

        await Promise.all(
          batch.map((chunk, idx) =>
            prisma.$executeRawUnsafe(
              `UPDATE "DocumentChunk" SET embedding = $1::vector WHERE id = $2`,
              embeddingService.toVectorString(embeddings[idx].embedding),
              chunk.id
            )
          )
        )
      }

      await prisma.noteAttachment.update({
        where: { id: attachmentId },
        data: { status: 'ready' },
      })
    } catch (error: any) {
      await prisma.noteAttachment.update({
        where: { id: attachmentId },
        data: { status: 'failed', error: error.message?.substring(0, 500) },
      })
      throw error
    }
  }
}

export const documentIngestionService = new DocumentIngestionService()