water-management-system/mobile-app/lib/config/app_config.dart

/// 应用全局配置
class AppConfig {
  static AppConfig? _instance;

  AppConfig._internal();

  factory AppConfig() {
    _instance ??= AppConfig._internal();
    return _instance!;
  }

  /// 环境配置
  AppEnvironment _environment = AppEnvironment.development;
  AppEnvironment get environment => _environment;

  /// 切换环境
  void setEnvironment(AppEnvironment env) {
    _environment = env;
  }

  /// API 基础地址
  String get baseUrl {
    switch (_environment) {
      case AppEnvironment.development:
        return 'https://dev-api.xayunmei.com';
      case AppEnvironment.staging:
        return 'https://staging-api.xayunmei.com';
      case AppEnvironment.production:
        return 'https://api.xayunmei.com';
    }
  }
}

/// 环境枚举
enum AppEnvironment {
  development,
  staging,
  production,
}