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lib/config/app_config.dart

@@ -0,0 +1,37 @@
+/// Configuration class that holds application settings.
+/// 
+/// This class contains environment-specific configuration values
+/// such as API base URL and logging settings.
+class AppConfig {
+  /// The base URL for API requests.
+  final String apiBaseUrl;
+
+  /// Whether logging is enabled in the application.
+  final bool enableLogging;
+
+  /// Creates an [AppConfig] instance with the provided values.
+  /// 
+  /// [apiBaseUrl] - The base URL for API requests.
+  /// [enableLogging] - Whether logging should be enabled.
+  const AppConfig({
+    required this.apiBaseUrl,
+    required this.enableLogging,
+  });
+
+  @override
+  String toString() {
+    return 'AppConfig(apiBaseUrl: $apiBaseUrl, enableLogging: $enableLogging)';
+  }
+
+  @override
+  bool operator ==(Object other) {
+    if (identical(this, other)) return true;
+    return other is AppConfig &&
+        other.apiBaseUrl == apiBaseUrl &&
+        other.enableLogging == enableLogging;
+  }
+
+  @override
+  int get hashCode => apiBaseUrl.hashCode ^ enableLogging.hashCode;
+}
+

lib/config/config_loader.dart

@@ -0,0 +1,51 @@
+import 'app_config.dart';
+
+/// Exception thrown when an invalid environment is provided to [ConfigLoader].
+class InvalidEnvironmentException implements Exception {
+  /// The invalid environment that was provided.
+  final String environment;
+
+  /// Creates an [InvalidEnvironmentException] with the provided environment.
+  InvalidEnvironmentException(this.environment);
+
+  @override
+  String toString() {
+    return 'InvalidEnvironmentException: Invalid environment "$environment". '
+        'Valid environments are: dev, prod';
+  }
+}
+
+/// Loads application configuration based on the specified environment.
+/// 
+/// This class provides a factory method to load configuration for either
+/// 'dev' or 'prod' environments. It throws [InvalidEnvironmentException]
+/// if an invalid environment is provided.
+class ConfigLoader {
+  /// Private constructor to prevent instantiation.
+  ConfigLoader._();
+
+  /// Loads configuration for the specified environment.
+  /// 
+  /// [environment] - The environment to load ('dev' or 'prod').
+  /// 
+  /// Returns an [AppConfig] instance for the specified environment.
+  /// 
+  /// Throws [InvalidEnvironmentException] if [environment] is not 'dev' or 'prod'.
+  static AppConfig load(String environment) {
+    switch (environment.toLowerCase()) {
+      case 'dev':
+        return const AppConfig(
+          apiBaseUrl: 'https://api-dev.example.com',
+          enableLogging: true,
+        );
+      case 'prod':
+        return const AppConfig(
+          apiBaseUrl: 'https://api.example.com',
+          enableLogging: false,
+        );
+      default:
+        throw InvalidEnvironmentException(environment);
+    }
+  }
+}
+