/***********************************************************************************************************************************************************************
 * File Name: asset_upload.middleware.js
 * Type of Program: Middleware
 * Description: Multer config for admin asset uploads (image/video/audio/document).
 *              Uses memory storage — buffer is passed directly to S3.
 *
 *              Previously this route had no `limits.fileSize` at all, so an
 *              oversized upload wasn't rejected cleanly — it either exhausted
 *              server memory buffering the whole file or blew up with a raw
 *              multer/Node error that never reached R.error's JSON envelope.
 *              The frontend's fallback then had nothing to read a `message`
 *              out of, so every failure surfaced as the same generic
 *              "Something went wrong" regardless of cause.
 *
 * Limits:
 *   fileSize: 500 MB (matches task_upload.middleware.js)
 *
 * Author: Kenneth Obsequio (@lash0000)
 * Date Created: Jul. 13, 2026
 ***********************************************************************************************************************************************************************/
const multer = require('multer');
const R = require('../utils/response.util');

const MAX_FILE_SIZE = 500 * 1024 * 1024; // 500 MB

const upload = multer({
    storage: multer.memoryStorage(),
    limits: { fileSize: MAX_FILE_SIZE },
});

// Wraps any multer middleware (fields/array/single) so oversized or malformed
// uploads always come back as a clean R.error JSON response the frontend can
// read a `message` out of, instead of an unhandled exception or Express's
// default HTML error page.
function handleUpload(multerMiddleware) {
    return (req, res, next) => {
        multerMiddleware(req, res, (err) => {
            if (!err) return next();

            if (err.code === 'LIMIT_FILE_SIZE') {
                return R.error(res, `File exceeds the ${MAX_FILE_SIZE / (1024 * 1024)} MB size limit.`, 400);
            }

            console.error('[MULTER ERROR][ASSETS]', err);
            return R.error(res, err.message ?? 'File upload failed.', 400);
        });
    };
}

module.exports = { upload, handleUpload, MAX_FILE_SIZE };