server/middleware/multer.ts

import multer from "multer";
import path from "path";
import { Request } from "express";

const storage = multer.diskStorage({
  destination: (req, file, cb) => {
    cb(null, 'uploads/');
  },
  filename: (req, file, cb) => {
    const uniqueSuffix = Date.now() + '-' + Math.round(Math.random() * 1E9);
    cb(null, file.fieldname + '-' + uniqueSuffix + path.extname(file.originalname));
  }
});

const fileFilter = (req: Request, file: Express.Multer.File, cb: multer.FileFilterCallback) => {
  // Allow only image files
  if (file.mimetype.startsWith('image/')) {
    cb(null, true);
  } else {
    cb(new Error('Only image files are allowed'));
  }
};

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