// load any env vars inside root of project's .env file, then looks for JWT_TOKEN_SECRET
import 'dart:io';
import 'dart:math';

import 'package:logging/logging.dart';

final log = Logger('Environment');

bool _isDevEnv = false;

void checkEnvironment({required bool isDevEnv}) {
  _isDevEnv = isDevEnv;
  getJWTSecret();
}

String? getJWTSecret() {
  final envs = {...Platform.environment};
  if (_isDevEnv) {
    log.fine('Trying to load .env file...');
    try {
      final result = Process.runSync('git', ['rev-parse', '--show-toplevel']);
      if (result.exitCode != 0) {
        log.warning('Failed to get git root directory: ${result.stderr}');
        throw Exception('Failed to get git root directory');
      }
      final rootDir = (result.stdout as String).trim();
      final envFile = File('$rootDir/.env');
      if (envFile.existsSync()) {
        for (final line in envFile.readAsLinesSync()) {
          if (line.trim().isEmpty || line.startsWith('#')) continue;
          final parts = line.split('=');
          if (parts.length != 2) continue;
          final key = parts[0].trim();
          final value = parts[1].trim();
          envs[key] = value;
        }
      }
    } catch (e) {
      log.warning('Failed to load .env file: $e');
    }
  }

  // check for secret
  final secret = envs['JWT_TOKEN_SECRET'];
  if (secret == null || secret.isEmpty) {
    if (_isDevEnv) {
      log.warning('JWT secret not configured. Define JWT_TOKEN_SECRET in environment.');
      final secret = List.generate(
        24,
        (_) => String.fromCharCode((65 + Random().nextInt(26)) + (Random().nextInt(2) == 0 ? 0 : 32)),
      ).join();
      log.warning('Generated random JWT secret for development: $secret');
      return secret;
    } else {
      log.severe('Stopping prod server because JWT secret is not defined.');
      throw Exception('JWT secret not configured. Define JWT_TOKEN_SECRET in environment.');
    }
  } else {
    return secret;
  }
}