import type { FastifyInstance } from 'fastify';
import { Prisma } from '@prisma/client';
import { prisma } from '../../db.js';
import { getOrganizationId } from '../../lib/org.js';
import { extractText } from './extract.js';
import { recognizeTemplate } from './recognize.js';

const MAX_BYTES = 20 * 1024 * 1024; // 20 MB

export async function templatesImportRoutes(app: FastifyInstance) {
  app.post(
    '/api/templates/import',
    { preHandler: app.requireDocPermission('user') },
    async (req, reply) => {
      const orgId = getOrganizationId(req);
      const file = await req.file({ limits: { fileSize: MAX_BYTES } });
      if (!file) {
        reply.code(400).send({ error: 'no_file' });
        return;
      }
      const buf = await file.toBuffer();
      const filename = file.filename || 'template';
      const mime = file.mimetype || '';

      // Опц. имя/тип передаются полями формы; если нет — определит LLM
      const fields = (file.fields ?? {}) as Record<string, { value?: string }>;
      const userName = typeof fields.name?.value === 'string' ? fields.name.value : null;
      const userDocType = typeof fields.docType?.value === 'string' ? fields.docType.value : null;

      try {
        // 1) Извлекаем текст
        const extracted = await extractText(buf, mime, filename);
        if (extracted.text.trim().length < 30) {
          reply.code(422).send({
            error: 'empty_extracted_text',
            message: 'Не удалось извлечь читаемый текст. Возможно, скан плохого качества.',
            source: extracted.source,
          });
          return;
        }

        // 2) Распознаём через DeepSeek
        const recognized = await recognizeTemplate(extracted.text);
        const docType = (userDocType as 'contract' | 'invoice' | 'act' | 'upd') ?? recognized.docType;
        const name = userName?.trim() || recognized.title || `Импорт ${new Date().toLocaleDateString('ru-RU')}`;

        const created = await prisma.documentTemplate.create({
          data: {
            organizationId: orgId,
            docType,
            name,
            body: recognized.docBody as Prisma.InputJsonValue,
          },
        });

        reply.code(201).send({
          template: created,
          extractedFrom: extracted.source,
          textLength: extracted.text.length,
        });
      } catch (e) {
        const err = e as { code?: string; message?: string; status?: number };
        if (err.code === 'NO_DEEPSEEK_KEY') {
          reply.code(503).send({ error: 'no_deepseek_key', message: err.message });
          return;
        }
        if (err.code === 'NO_OCR') {
          reply.code(503).send({ error: 'no_ocr', message: err.message });
          return;
        }
        if (err.code === 'UNSUPPORTED_MIME') {
          reply.code(415).send({ error: 'unsupported_mime', message: err.message });
          return;
        }
        if (err.code === 'INVALID_DOC_BODY') {
          reply.code(502).send({
            error: 'invalid_doc_body',
            message: 'LLM вернула структуру, не прошедшую валидацию. Попробуйте загрузить ещё раз или отредактировать вручную.',
          });
          return;
        }
        if (err.code === 'DEEPSEEK_HTTP_ERROR') {
          reply.code(502).send({
            error: 'deepseek_error',
            message: err.message,
            status: err.status ?? 502,
          });
          return;
        }
        app.log.error({ err: e }, 'template import failed');
        reply.code(500).send({ error: 'import_failed', message: err.message ?? 'unknown' });
      }
    },
  );
}