import path from 'node:path';
import crypto from 'node:crypto';
import multer from 'multer';
import { config } from '../config.js';
import { HttpError } from './errors.js';

const storage = multer.diskStorage({
  destination: path.join(config.storageDir, 'uploads'),
  filename(req, file, callback) {
    const safe = file.originalname.replace(/[^a-zA-Z0-9._-]/g, '_');
    callback(null, `${Date.now()}-${crypto.randomUUID()}-${safe}`);
  }
});

function fileFilter(req, file, callback) {
  const allowed = new Set([
    'application/gpx+xml', 'application/xml', 'text/xml',
    'image/jpeg', 'image/png', 'image/webp',
    'audio/mpeg', 'audio/mp4', 'audio/x-m4a', 'audio/aac', 'audio/ogg', 'audio/wav', 'audio/webm'
  ]);
  const extension = path.extname(file.originalname).toLowerCase();
  if (allowed.has(file.mimetype) || extension === '.gpx') return callback(null, true);
  callback(new HttpError(415, `Dateityp nicht unterstützt: ${file.originalname}`));
}

export const upload = multer({
  storage,
  limits: { fileSize: config.maxUploadBytes, files: 25 },
  fileFilter
});