ideas-generator/server/routes/files.js

const express = require('express');
const multer = require('multer');
const path = require('path');
const fs = require('fs');
const { v4: uuidv4 } = require('uuid');
const OpenAI = require('openai');

const router = express.Router();

const openai = new OpenAI({
  apiKey: process.env.OPENAI_API_KEY,
  organization: process.env.OPENAI_ORG_ID,
});

// Configure multer for temporary file uploads
const tempStorage = multer.diskStorage({
  destination: function (req, file, cb) {
    const uploadDir = path.join(__dirname, '../temp-uploads');
    if (!fs.existsSync(uploadDir)) {
      fs.mkdirSync(uploadDir, { recursive: true });
    }
    cb(null, uploadDir);
  },
  filename: function (req, file, cb) {
    const uniqueName = uuidv4() + path.extname(file.originalname);
    cb(null, uniqueName);
  }
});

const tempUpload = multer({
  storage: tempStorage,
  limits: {
    fileSize: 50 * 1024 * 1024, // 50MB limit for temporary files
  },
  fileFilter: (req, file, cb) => {
    // Allow common document and image types for chat
    const allowedTypes = [
      'application/pdf',
      'text/plain',
      'text/markdown',
      'application/msword',
      'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
      'text/csv',
      'application/json',
      'image/jpeg',
      'image/png',
      'image/gif',
      'image/webp'
    ];
    
    if (allowedTypes.includes(file.mimetype)) {
      cb(null, true);
    } else {
      cb(new Error('Unsupported file type for temporary upload.'));
    }
  }
});

// Upload file for temporary chat use
router.post('/temp-upload', tempUpload.single('file'), async (req, res, next) => {
  try {
    if (!req.file) {
      return res.status(400).json({
        error: 'Validation Error',
        message: 'No file uploaded'
      });
    }

    console.log(`Temporary file uploaded: ${req.file.originalname}`);

    // For images, we can use them directly with vision models
    if (req.file.mimetype.startsWith('image/')) {
      // Convert to base64 for vision API
      const imageBuffer = fs.readFileSync(req.file.path);
      const base64Image = imageBuffer.toString('base64');
      
      res.json({
        id: req.file.filename,
        name: req.file.originalname,
        type: 'image',
        mimeType: req.file.mimetype,
        size: req.file.size,
        data: `data:${req.file.mimetype};base64,${base64Image}`,
        message: 'Image uploaded for chat analysis'
      });
    } else {
      // For documents, upload to OpenAI for processing
      try {
        const openaiFile = await openai.files.create({
          file: fs.createReadStream(req.file.path),
          purpose: 'assistants'
        });

        console.log(`Document uploaded to OpenAI: ${openaiFile.id}`);

        res.json({
          id: req.file.filename,
          name: req.file.originalname,
          type: 'document',
          mimeType: req.file.mimetype,
          size: req.file.size,
          openaiFileId: openaiFile.id,
          message: 'Document uploaded for chat analysis'
        });
      } catch (openaiError) {
        console.error('Error uploading to OpenAI:', openaiError);
        res.json({
          id: req.file.filename,
          name: req.file.originalname,
          type: 'document',
          mimeType: req.file.mimetype,
          size: req.file.size,
          error: 'Failed to process with OpenAI, but file uploaded locally',
          message: 'Document uploaded locally (OpenAI processing failed)'
        });
      }
    }

    // Schedule cleanup after 1 hour
    setTimeout(() => {
      if (fs.existsSync(req.file.path)) {
        fs.unlinkSync(req.file.path);
        console.log(`Cleaned up temporary file: ${req.file.filename}`);
      }
    }, 60 * 60 * 1000); // 1 hour

  } catch (error) {
    console.error('Error with temporary file upload:', error);
    
    // Clean up uploaded file if there was an error
    if (req.file && fs.existsSync(req.file.path)) {
      fs.unlinkSync(req.file.path);
    }
    
    next(error);
  }
});

// Get temporary file info (for chat reference)
router.get('/temp/:fileId', async (req, res, next) => {
  try {
    const { fileId } = req.params;
    const filePath = path.join(__dirname, '../temp-uploads', fileId);

    if (!fs.existsSync(filePath)) {
      return res.status(404).json({
        error: 'Not Found',
        message: 'Temporary file not found or expired'
      });
    }

    const stats = fs.statSync(filePath);
    const ext = path.extname(fileId);
    
    res.json({
      id: fileId,
      exists: true,
      size: stats.size,
      uploadedAt: stats.birthtime,
      extension: ext
    });

  } catch (error) {
    console.error('Error getting temporary file info:', error);
    next(error);
  }
});

module.exports = router;