/**
 * Copyright (c) 2026 Niolla
 * All rights reserved.
 *
 * This source code is proprietary and confidential.
 * Unauthorized copying, modification, distribution, or use
 * of this file, via any medium, is strictly prohibited.
 */

// app/middlewares/upload.middleware.js

const multer = require("multer");

// Use memory storage (required for S3 upload)
const storage = multer.memoryStorage();

// File filter (only images + PDFs)
const fileFilter = (req, file, cb) => {
    const allowedTypes = [
    "image/",
    "application/pdf",
    "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", // .xlsx
    "application/vnd.ms-excel" // .xls
  ];

  const isValid =
    file.mimetype.startsWith("image/") ||
    file.mimetype === "application/pdf" ||
    file.mimetype === "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" ||
    file.mimetype === "application/vnd.ms-excel";

  if (isValid) {
    cb(null, true);
  } else {
    cb(new Error("Only images, PDFs, and Excel files are allowed"), false);
  }
};

// Multer instance
const upload = multer({
  storage,
  fileFilter,
  limits: {
    fileSize: 5 * 1024 * 1024, // max 5MB (global limit)
  },
});

// Middleware wrappers

// Single file upload
const uploadSingle = (fieldName) => upload.single(fieldName);

// Multiple files (same field)
const uploadMultiple = (fieldName, maxCount = 5) =>
  upload.array(fieldName, maxCount);

// Multiple fields (advanced)
const uploadFields = (fields) => upload.fields(fields);

module.exports = {
  uploadSingle,
  uploadMultiple,
  uploadFields,
};