arcane_framework/README.md

# Arcane Framework

> _**A**gnostic **R**eusable **C**omponent **A**rchitecture for **N**ew
> **E**cosystems_

![style: arcane analysis](https://img.shields.io/badge/style-arcane_analysis-6E35AE)

The Arcane Framework is a powerful Dart package designed to provide a robust
architecture for managing key application services such as logging,
authentication, feature flags, theming, and more. This framework
is ideal for building scalable applications that require dynamic configuration
and service management.

- [Arcane Framework](#arcane-framework)
  - [Features](#features)
  - [Installation](#installation)
    - [ArcaneApp Builder Migration (v1.x -\> v2.x)](#arcaneapp-builder-migration-v1x---v2x)
    - [Arcane.log Metadata Migration (v1.x -\> v2.x)](#arcanelog-metadata-migration-v1x---v2x)
  - [Usage](#usage)
    - [Services](#services)
      - [Defining an example `ArcaneService`](#defining-an-example-arcaneservice)
      - [Registering and unregistering an `ArcaneService`](#registering-and-unregistering-an-arcaneservice)
      - [Locating an `ArcaneService`](#locating-an-arcaneservice)
      - [Using `ArcaneService` services](#using-arcaneservice-services)
    - [Feature Flags](#feature-flags)
    - [Logging](#logging)
    - [Authentication](#authentication)
    - [Application Environments](#application-environments)
    - [Dynamic Theming](#dynamic-theming)
  - [Contributing](#contributing)

## Features

- **Service Management**: Centralized access to multiple services (logging,
  authentication, theming, etc.).
- **Feature Flags**: Dynamically enable or disable features using
  `ArcaneFeatureFlagService`.
- **Logging**: Easily log messages with metadata, stack traces, and different
  log levels via `ArcaneLogger`.
- **Authentication**: Built-in support for handling user authentication
  workflows.
- **Dynamic Theming**: Switch between light and dark themes and update theme
  definitions on-the-fly with `ArcaneThemeService`.
- **Extensible Service Definitions**: Implement your own `ArcaneService` services and leverage the inherent powers of Arcane.
- **Realtime Streams**: In addition to `ValueNotifier`s, core services expose
  broadcast streams for reactive consumers.

## Installation

To use Arcane Framework in your Dart or Flutter project, follow these steps:

 1. Add the dependency to your `pubspec.yaml`:

    ```shell
    flutter pub add arcane_framework
    ```

 2. (optional) Wrap your `MaterialApp` or `CupertinoApp` with `ArcaneApp`.
   `ArcaneApp` wires up Arcane's built-in app-level providers for services,
   feature flags, environment, and theme updates:

    ```dart
    import 'package:arcane_framework/arcane_framework.dart';
    
    void main() {
      runApp(
        ArcaneApp(
          builder: (context, _) => MainApp(),
        ),
      );
    }
    ```

   `ArcaneApp.child` remains available for backward compatibility, but is
   deprecated in favor of `ArcaneApp.builder`.

### ArcaneApp Builder Migration (v1.x -> v2.x)

Arcane now prefers `ArcaneApp.builder` over `ArcaneApp.child`.

Why this is better:

- Your app root is built with Arcane providers already in scope.
- You can access Arcane-backed context values immediately at app-root build
  time.
- You no longer need an extra `Builder` wrapper just to capture provider-aware
  context.

When to use each API:

| Situation                                                              | Recommended API                | Why                                                                      |
| ---------------------------------------------------------------------- | ------------------------------ | ------------------------------------------------------------------------ |
| New app code                                                           | `ArcaneApp.builder`            | Preferred, future-facing API.                                            |
| Root widget needs Arcane-aware `BuildContext` during construction      | `ArcaneApp.builder`            | Context is captured inside Arcane's provider tree.                       |
| Existing app already uses `child` and you want minimal churn right now | `ArcaneApp.child` (deprecated) | Still supported for compatibility while you migrate.                     |
| You only need to pass through a static root widget                     | `ArcaneApp.builder`            | Keeps usage consistent with migration target and avoids later refactors. |

Migration example:

```dart
// Before (deprecated)
ArcaneApp(
  child: MainApp(),
)

// After (preferred)
ArcaneApp(
  builder: (context, _) => MainApp(),
)
```

### Arcane.log Metadata Migration (v1.x -> v2.x)

`Arcane.log(...)` now accepts `metadata` as `Map<String, Object?>?`.
This allows metadata values to be non-strings (for example `int`, `bool`,
lists, or nested maps).

Migration example:

```dart
// Before
Arcane.log(
  "Login attempt",
  metadata: {
    "userId": userId.toString(),
    "attempt": attempt.toString(),
    "rememberMe": rememberMe.toString(),
  },
);

// After
Arcane.log(
  "Login attempt",
  metadata: {
    "userId": userId,
    "attempt": attempt,
    "rememberMe": rememberMe,
  },
);
```

If your logger destination serializes metadata, ensure it can handle
`Object?` values (or convert values to strings at that boundary).

## Usage

The following sections provide more information about how to use the package's
available features.

### Services

The Arcane Framework provides a centralized way to manage services across your
application, while optionally leveraging a built-in service locator.

Unlike most of the features in Arcane, a _service_ is broadly user-defined. What
a service is, or does, is not rigorously enforced by the framework itself. What
an `ArcaneService` offers, however, is the ability to be registered (and
unregistered), as well as located via `BuildContext`. The locators are the key
value proposition that Arcane provides.

The following tools are provided by Arcane to assist with creating and using
services:

- `ArcaneService`: The base class from which to extend your own services. This
  what Arcane uses to locate services.
- `ArcaneServiceProvider`: A widget used to provide access to registered
  `ArcaneService` instances. **Note**: This widget is already part of the
  _`ArcaneApp`_ widget, however if you are not using the `ArcaneApp` widget you
  can instead use this widget directly.
- The `service<T>` and `requiredService<T>` extensions on `BuildContext`:
  nullable and non-nullable getters used to locate a given `ArcaneService` via
  `BuildContext`. **Note**: For app-defined services, these lookups require an
  `ArcaneServiceProvider` in the widget tree. For Arcane built-in singleton
  services (such as `Arcane.auth`, `Arcane.features`, `Arcane.theme`, and
  `Arcane.environment`), lookups fall back to built-ins even when no provider
  is available.

#### Defining an example `ArcaneService`

As noted previously, _what_ a service is or does is not enforced by the
framework. Therefore, the following example is only in service of the remainder
of the documentation of the Arcane services feature.

This example service is a singleton service that stores and provides access to a
user's favorite color, leveraging a `ValueNotifier` to trigger rebuilds as
appropriate:

```dart
class FavoriteColorService extends ArcaneService {

  FavoriteColorService();

  final ValueNotifier<Color?> _notifier = ValueNotifier<Color?>(null);
  ValueNotifier<Color?> get notifier => _notifier;

  Color? get myFavoriteColor => _notifier.value;

  void setMyFavoriteColor(Color? color) {
    if (_notifier.value != color) {
      _notifier.value = color;
    }
  }
}
```

#### Registering and unregistering an `ArcaneService`

The quickest and easiest way to register an `ArcaneService` is to use the
built-in `ArcaneApp` widget. However, this is not the _only_ method available.

To register your `ArcaneService` using an app with the `ArcaneApp` widget, you
have a couple of options. First, you can simply add the service (in our case, a
singleton instance) to the `services` list directly:

```dart
ArcaneApp(
  services: [
    FavoriteColorService(),
  ],
  builder: (context, _) => MainApp(),
),
```

You can also defer adding the service by invoking `ArcaneServiceProvider`. Note
that this requires either `ArcaneServiceProvider` _or_ `ArcaneApp` (which
already includes `ArcaneServiceProvider`) to be in your widget tree.

```dart
// The service is not included at compile-time
ArcaneApp(
  builder: (context, _) => MainApp(),
),

// Add the service at runtime
ArcaneServiceProvider.of(context).addService(FavoriteColorService());
```

Unregistering an already registered `ArcaneService` is as simple as:

```dart
ArcaneServiceProvider.of(context).removeService<FavoriteColorService>()
```

When both a provider-registered service and an Arcane built-in singleton match
the same requested type, provider-registered services take precedence for
`context.service<T>()` and `context.requiredService<T>()`.

#### Locating an `ArcaneService`

There are numerous ways to locate a registered `ArcaneService`. Feel free to use
whatever method you prefer:

```dart
// If a service of the given type is not registered, `null` is returned.
final FavoriteColorService? nullableService = ArcaneService.ofType<FavoriteColorService>(context);
final FavoriteColorService? nullableViaContext = context.service<FavoriteColorService>();
final FavoriteColorService? nullableViaProvider = ArcaneServiceProvider.serviceOfType<FavoriteColorService>(context);

// If a service of the given type is not registered, an exception is thrown.
final FavoriteColorService nonNullableService = ArcaneService.requiredOfType<FavoriteColorService>(context);
final FavoriteColorService nonNullableViaContext = context.requiredService<FavoriteColorService>();
final FavoriteColorService nonNullableViaProvider = ArcaneServiceProvider.requiredServiceOfType<FavoriteColorService>(context);
```

In addition, you can locate a `ArcaneServiceProvider` in a similar way:

```dart
// Returns `null` if no `ArcaneServiceProvider` is found in the widget tree.
final ArcaneServiceProvider? nullableProvider = ArcaneServiceProvider.maybeOf(context);

// Throws an exception if no `ArcaneServiceProvider` is found in the widget tree.
final ArcaneServiceProvider nonNullableProvider = ArcaneServiceProvider.of(context);
```

#### Using `ArcaneService` services

Since the `ArcaneService` class includes a `ChangeNotifier`, invoking the
`notifyListeners()` method inside a service will trigger a rebuild. Using our
`FavoriteColorService` from earlier, we can add a listener to our notifier
value:

```dart
final FavoriteColorService service = ArcaneService.requiredOfType<FavoriteColorService>(context);

service.notifier.addListener(() {
  final Color? color = service.myFavoriteColor;
  // Do something with our value
});
```

We can also simply use a `ValueListenableBuilder`:

```dart
ValueListenableBuilder(
  valueListenable: ArcaneService.requiredOfType<FavoriteColorService>(context).notifier,
  builder: (context, color, _) {
    return Text("My favorite color is $color"),
  }
)
```

Meanwhile, setting the value in our service can be accomplished in the following
manner:

```dart
ArcaneService.requiredOfType<FavoriteColorService>(context).setMyFavoriteColor(Colors.purple);
```

Again, this example is _not_ the only way the Arcane Service system can be
utilized. One is limited only by their imagination!

### Feature Flags

You can easily manage feature flags using the `ArcaneFeatureFlagService` built-in
service. Feature flags are useful for enabling or disabling different parts of
your application under different circumstances. For example, you may want to
enable a new feature only once it has finished development and testing, while
still having the ability to ship the unfinished code. You could also leverage
feature flags to enable different modes within your application (e.g., "free" vs
"paid"). Furthermore, they can be used for A/B testing. The options are truly
unlimited.

To get started, create an `enum` to define your features:

```dart
enum Feature {
  awesomeFeature(true),
  prettyOkFeature(false),
  ;

  /// Determines whether the given [Feature] is enabled by default when the
  /// application launches. Features can be enabled or disabled during runtime,
  /// regardless of this value.
  final bool enabledAtStartup;

  const Feature(this.enabledAtStartup);
}
```

Next, ensure that your features are enabled at startup by registering them
within the feature flag service:

```dart
void main() {
    WidgetsFlutterBinding.ensureInitialized();

    // Register your Enum that you'll be using to enable and disable features.
    for (final Feature feature in Feature.values) {
      if (feature.enabledAtStartup) Arcane.features.enableFeature(feature);
    }

    runApp(
      ArcaneApp(
        builder: (context, _) => MainApp(),
      ),
    );
  }
```

When you want to determine if a feature is enabled, you can use one of the
helper extensions:

```dart
// Via an enum extension
final bool isMyAwesomeFeatureEnabled = Feature.awesomeFeature.enabled;

// Via the Arcane feature flag service
final bool isMyPrettyOkFeatureDisabled = Arcane.features.isDisabled(Feature.prettyOkFeature);
```

You can also enable and disable features at runtime:

```dart
// Via an enum extension
Feature.awesomeFeature.disable();
Feature.prettyOkFeature.enable();

// Via the Arcane features service
Arcane.features.disableFeature(Feature.awesomeFeature);
Arcane.features.enableFeature(Feature.prettyOkFeature);
```

To get a list of the currently enabled features, simply ask the Arcane feature
flag service:

```dart
final List<Enum> enabledFeatures = Arcane.features.enabledFeatures;
```

`enabledFeatures` is a snapshot read. Reading it does not subscribe to updates
and does not trigger widget rebuilds.

It is also possible to add a listener to watch for changes in the enabled
features.

```dart
Arcane.features.notifier.addListener(() {
  print("Features changed: ${Arcane.features.enabledFeatures}");
});
```

If you prefer stream-based subscriptions, you can listen to
`enabledFeaturesChanges` and cancel the subscription in `dispose`.

```dart
late final StreamSubscription<List<Enum>> subscription;

@override
void initState() {
  super.initState();
  subscription = Arcane.features.enabledFeaturesChanges.listen((features) {
    print("Features changed: $features");
  });
}

@override
void dispose() {
  subscription.cancel();
  super.dispose();
}
```

When using `ArcaneApp`, you can also depend on feature flags via
`context.featureFlags`. This resolves to the nearest
`ArcaneFeatureFlagProvider` and widgets that read it rebuild automatically when
feature flags change.

```dart
class FeatureGate extends StatelessWidget {
  const FeatureGate({super.key});

  @override
  Widget build(BuildContext context) {
    final flags = context.featureFlags;
    if (flags.isDisabled(Feature.awesomeFeature)) {
      return const SizedBox.shrink();
    }

    return const Text("Awesome feature enabled");
  }
}
```

Additional `BuildContext` helpers are also available:

```dart
final ArcaneFeatureFlagProvider? maybeFlags = context.maybeFeatureFlags;

if (context.isFeatureEnabled(Feature.awesomeFeature)) {
  // Feature is enabled
}

if (context.isFeatureDisabled(Feature.prettyOkFeature)) {
  // Feature is disabled
}
```

Note that it is possible to register multiple different `Enum` types in the
feature flag service, should one have a need to do so.

### Logging

The Arcane Framework provides a robust logging system for your application. This
allows you to log messages with metadata, stack traces, and different log
levels while routing a single log event to multiple destinations.

To get started, first create one or more logging interfaces by extending
`LoggingInterface`.

```dart
class DebugConsole extends LoggingInterface {
  @override
  void log(
    String message, {
    Map<String, Object?>? metadata,
    Level? level,
    StackTrace? stackTrace,
    Object? extra,
  }) {
    debugPrint(
      "$message\n"
      "$metadata\n",
    );
  }
}
```

If your destination needs setup (SDK start, permission checks, etc.), opt into
the initialization lifecycle with `LoggingInitialization`:

```dart
class ExternalLogger extends LoggingInterface with LoggingInitialization {
  @override
  Future<void> init() async {
    if (initialized) return;

    // Configure and start the SDK.
    await super.init();
  }

  @override
  void log(
    String message, {
    Map<String, Object?>? metadata,
    Level? level,
    StackTrace? stackTrace,
    Object? extra,
  }) {
    if (!initialized) return;
    // Forward to the SDK.
  }
}
```

If you want to tag a destination, annotate the interface with
`@LoggingFeature(...)`:

```dart
@LoggingFeature("Analytics")
class AnalyticsLogger extends LoggingInterface {

  @override
  void log(
    String message, {
    Map<String, Object?>? metadata,
    Level? level,
    StackTrace? stackTrace,
    Object? extra,
  }) {
    // Forward to analytics pipeline.
  }
}

Arcane.logger.registerInterceptor(
  LogInterceptor((event, context) {
    if (context.interface is AnalyticsLogger && event.level == Level.debug) {
      return null;
    }

    return event;
  }),
);
```

You can use this tag as source-level documentation and keep destination routing
explicit in interceptors.

```dart
@LoggingFeature("auth")
class AuthLogger extends LoggingInterface {
  @override
  void log(
    String message, {
    Map<String, Object?>? metadata,
    Level? level,
    StackTrace? stackTrace,
    Object? extra,
  }) {
    // Forward to auth destination.
  }
}

await Arcane.logger.registerInterface(AnalyticsLogger());
await Arcane.logger.registerInterface(AuthLogger());
```

Next, register your logging interface with the Arcane logger service. You can
attach interceptors when registering an interface, or add global interceptors
later at runtime.

```dart
final DebugConsole debugConsole = DebugConsole();

await Arcane.logger.registerInterface(
  debugConsole,
  interceptors: [
    LogInterceptor((event, context) {
      if (context.interface is DebugConsole && event.level == Level.debug) {
        return null;
      }

      return event;
    }),
  ],
);

Arcane.logger.registerInterceptor(
  LogInterceptor((event, context) {
    return event.copyWith(
      metadata: {
        ...?event.metadata,
        "session": "startup",
      },
    );
  }),
);

// Optional: initialize only interfaces that implement LoggingInitializable
// (for example, SDK-backed loggers that mix in LoggingInitialization).
await Arcane.logger.initializeInterfaces();
```

Global interceptors are evaluated for each registered interface, and interface
interceptors run immediately after them for that same destination. Every
interceptor receives a `LogInterceptorContext` whose `interface` value is the
current destination, which allows a single global interceptor to allow one
interface to receive an event while dropping it for another.

Returning `null` from an interceptor drops the event for the current scope.
Returning a modified `LogEvent` allows you to rewrite the message, metadata,
level, stack trace, or extra payload before it is logged.

Finally, add any additional persistent metadata to your log messages (optional)
and log a message:

```dart
// Add metadata to the logger
Arcane.logger.addPersistentMetadata({
  "app_name": "My App",
  "environment": "production",
});

// Log a message!
Arcane.log(
  "This is a debug message",
  level: Level.debug,
  module: "ModuleName",
  method: "MethodName",
  metadata: {
    "key": "value",
    "attempt": 1,
    "retryable": true,
  },
  stackTrace: StackTrace.current,
);

// Optional: skip automatic module/method/file-line detection.
Arcane.log(
  "Manual log routing",
  module: "CustomModule",
  method: "customMethod",
  skipAutodetection: true,
);
```

You can also listen to `logStream` for realtime log events, and cancel and
re-register subscribers as widget lifecycles change:

```dart
late final StreamSubscription<String> logSubscription;

@override
void initState() {
  super.initState();
  logSubscription = Arcane.logger.logStream.listen((message) {
    debugPrint("Log stream event: $message");
  });
}

@override
void dispose() {
  logSubscription.cancel();
  super.dispose();
}
```

You can also add and remove global interceptors after startup. Because every
interceptor receives a `LogInterceptorContext`, a single global interceptor can
still make interface-specific decisions by checking `context.interface`. If you
prefer, you can also define your own interceptor class by implementing
`LogInterceptor` instead of using the callback constructor.

```dart
final LogInterceptor redactSecrets = LogInterceptor((
  event,
  context,
) {
  final Object? token = event.metadata?["token"];
  if (token == null) return event;

  return event.copyWith(
    metadata: {
      ...?event.metadata,
      "token": "[redacted]",
    },
  );
});

Arcane.logger.registerInterceptor(redactSecrets);
Arcane.logger.unregisterInterceptor(redactSecrets);
```

If you prefer a reusable named type, you can also implement `LogInterceptor`
directly:

```dart
class RedactingLogInterceptor implements LogInterceptor {
  const RedactingLogInterceptor();

  @override
  LogEvent? call(
    LogEvent event, {
    required LogInterceptorContext context,
  }) {
    final Object? token = event.metadata?["token"];
    if (token == null) return event;

    return event.copyWith(
      metadata: {
        ...?event.metadata,
        "token": "[redacted]",
      },
    );
  }
}

final LogInterceptor redactSecrets = RedactingLogInterceptor();

Arcane.logger.registerInterceptor(redactSecrets);
Arcane.logger.unregisterInterceptor(redactSecrets);
```

Multiple logging interfaces and multiple interceptors can be registered
simultaneously. Interface-specific interceptors receive copied `LogEvent`
instances, so mutations made for one destination do not leak into another.

**Important**: Initialization is now optional per interface. Call
`initializeInterfaces()` when you have interfaces that opt into
`LoggingInitializable` (for example via `LoggingInitialization`). Simple
destinations like a debug console can skip initialization entirely.

### Authentication

The Arcane Framework provides a useful interface for performing common
authentication tasks, such as registration, password resets, login, log out, and
enabling a debug mode.

To get started, create an authentication interface provider and register it in
the Arcane authentication module:

```dart
import "package:arcane_framework/arcane_framework.dart";

typedef Credentials = ({String email, String password});

class DebugAuthInterface
  with ArcaneAuthAccountRegistration, ArcaneAuthPasswordManagement
  implements ArcaneAuthInterface {
  DebugAuthInterface._internal();

  static final ArcaneAuthInterface _instance = DebugAuthInterface._internal();
  static ArcaneAuthInterface get I => _instance;

  @override
  Future<bool> get isSignedIn => Future.value(_isSignedIn);
  bool _isSignedIn = false;

  @override
  Future<String?> get accessToken => isSignedIn.then(
        (loggedIn) => loggedIn ? "access_token" : null,
      );

  @override
  Future<String?> get refreshToken => isSignedIn.then(
        (loggedIn) => loggedIn ? "refresh_token" : null,
      );

  @override
  Future<Result<void, String>> logout({
    Future<void> Function()? onLoggedOut,
  }) async {
    Arcane.log("Logging out");

    _isSignedIn = false;

    if (onLoggedOut != null) await onLoggedOut();

    return Result.ok(null);
  }

  @override
  Future<Result<void, String>> login<Credentials>({
    Credentials? input,
    Future<void> Function()? onLoggedIn,
  }) async {
    final bool alreadyLoggedIn = await isSignedIn;

    if (alreadyLoggedIn) return Result.ok(null);

    final credentials = input as ({String email, String password});

    final String email = credentials.email;
    final String password = credentials.password;

    Arcane.log("Logging in as $email using password $password");

    _isSignedIn = true;

    return Result.ok(null);
  }

  // Provided by the ArcaneAuthAccountRegistration mixin
  @override
  Future<Result<String, String>> resendVerificationCode<T>({
    T? input,
  }) async {
    Arcane.log("Re-sending verification code to $input");
    return Result.ok("Code sent");
  }

  // Provided by the ArcaneAuthAccountRegistration mixin
  @override
  Future<Result<SignUpStep, String>> register<Credentials>({
    Credentials? input,
  }) async {
    if (input != null) {
      final credentials = input as ({String email, String password});

      final String email = credentials.email;
      final String password = credentials.password;

      Arcane.log("Creating account for $email with password $password");
    }

    return Result.ok(SignUpStep.confirmSignUp);
  }

  // Provided by the ArcaneAuthAccountRegistration mixin
  @override
  Future<Result<bool, String>> confirmSignup({
    String? username,
    String? confirmationCode,
  }) async {
    Arcane.log(
      "Confirming registration for $username with code $confirmationCode",
    );
    return Result.ok(true);
  }

  // Provided by the ArcaneAuthPasswordManagement mixin
  @override
  Future<Result<bool, String>> resetPassword({
    String? email,
    String? newPassword,
    String? code,
  }) async {
    Arcane.log("Resetting password for $email");
    return Result.ok(true);
  }

  @override
  Future<void> init() async {
    Arcane.log("Debug auth interface initialized.");
    return;
  }
}



// Register an interface to handle user authentication.
await Arcane.auth.registerInterface(DebugAuthInterface.I);
```

Once your interface has been created and registered, you can use it to perform a
number of common authentication tasks:

```dart
// Register an account using the ArcaneAuthAccountRegistration mixin
  final nextStep = await Arcane.auth.register<Credentials>(
    input: (email: "user@example.com", password: "password123"),
  );

// Confirm a newly registered account using the ArcaneAuthAccountRegistration mixin
final accountConfirmed = await Arcane.auth.confirmSignup(
  email: "user@example.com",
  confirmationCode: "123456",
);

// Re-send a verification code using the ArcaneAuthAccountRegistration mixin
final response = await Arcane.auth.resendVerificationCode("user@example.com");

// Initiate a password reset flow using the ArcaneAuthPasswordManagement mixin
final passwordResetStarted = await Arcane.auth.resetPassword(
  email: "user@example.com",
  newPassword: "password456",
);

// Confirm password reset using the ArcaneAuthPasswordManagement mixin
final passwordResetFinished = await Arcane.auth.resetPassword(
  email: "user@example.com",
  newPassword: "password456",
  confirmationCode: "123456",
);

// Sign in with email and password
final result = await Arcane.auth.login(
  input: (email: "user@example.com", password: "password123"),
  onLoggedIn: () => Arcane.log("User logged in"),
);

// Sign out
await Arcane.auth.logOut();
```

Authentication updates can also be consumed through streams:

```dart
late final StreamSubscription<AuthenticationStatus> statusSubscription;
late final StreamSubscription<bool> signedInSubscription;

@override
void initState() {
  super.initState();

  statusSubscription = Arcane.auth.statusChanges.listen((status) {
    debugPrint("Auth status changed: $status");
  });

  signedInSubscription = Arcane.auth.signedInChanges.listen((signedIn) {
    debugPrint("Is signed in: $signedIn");
  });
}

@override
void dispose() {
  statusSubscription.cancel();
  signedInSubscription.cancel();
  super.dispose();
}
```

### Application Environments

Arcane environments are value-based and extensible. Two built-in values are
provided (`Environment.normal` and `Environment.debug`), and applications can define
their own environments (for example, `staging`).

```dart
const Environment staging = Environment("staging");

class EnvironmentSwitcher extends StatelessWidget {
  const EnvironmentSwitcher({super.key});

  @override
  Widget build(BuildContext context) {
    final ArcaneEnvironmentService environment = Arcane.environment;

    return ElevatedButton(
      onPressed: () {
        environment.setEnvironment(staging);
      },
      child: const Text("Use staging"),
    );
  }
}
```

`enableDebugMode()` and `disableDebugMode()` are still available convenience
helpers that map to the built-in debug and normal environments.

`ArcaneEnvironment` and `ArcaneEnvironmentProvider` are still available for
backward compatibility, but are deprecated in favor of
`Arcane.environment`/`ArcaneEnvironmentService`.

Authentication status is intentionally separate from environment. Switching
environments does not change `AuthenticationStatus`.

### Dynamic Theming

The Arcane Framework provides a simple interface for managing themes in your
application, with dynamic switching between dark and light themes based on the
user's system settings, or manually switching between themes.

To get started, first register your `ThemeData` objects with the Arcane theme
module:

```dart
void main() {
  // Set your Themes
  Arcane.theme
    ..setDarkTheme(darkTheme)
    ..setLightTheme(lightTheme);

  runApp(
    ArcaneApp(
      builder: (context, _) => MainApp(),
    ),
  );
}
```

From here, you can either follow the system theme:

```dart
// ArcaneApp already enables system-follow behavior by default.
class MainApp extends StatelessWidget {
  const MainApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: Arcane.theme.light,
      darkTheme: Arcane.theme.dark,
      themeMode: Arcane.theme.currentModeOf(context),
    );
  }
}
```

You can also manually control the theme mode:

```dart
// Manually control the theme mode
class MainApp extends StatelessWidget {
  const MainApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: Arcane.theme.light,
      darkTheme: Arcane.theme.dark,
      themeMode: Arcane.theme.currentModeOf(context),
    );
  }
}
```

Then, you can switch modes whenever you want:

```dart
// Switch between light and dark themes
Arcane.theme.switchTheme();

// Access current theme data
final ThemeData currentTheme = Arcane.theme.currentThemeMode == ThemeMode.dark
  ? Arcane.theme.dark
  : Arcane.theme.light;

if (context.isDarkMode) {
  // Do something when dark mode is active
}

// Set a custom dark theme
Arcane.theme.setDarkTheme(customDarkTheme);

// Equivalent assignment-style setter
Arcane.theme.dark = customDarkTheme;

// Set a custom light theme
Arcane.theme.setLightTheme(customLightTheme);

// Equivalent assignment-style setter
Arcane.theme.light = customLightTheme;
```

You can subscribe to theme streams to react to theme updates outside of widget
build methods:

```dart
late final StreamSubscription<ThemeMode> modeSubscription;
late final StreamSubscription<ThemeData> themeSubscription;

@override
void initState() {
  super.initState();
  modeSubscription = Arcane.theme.themeModeChanges.listen((mode) {
    debugPrint("Theme mode changed: $mode");
  });
  themeSubscription = Arcane.theme.themeDataChanges.listen((themeData) {
    debugPrint("Theme data changed: ${themeData.brightness}");
  });
}

@override
void dispose() {
  modeSubscription.cancel();
  themeSubscription.cancel();
  super.dispose();
}
```

## Contributing

We welcome contributions to the Arcane Framework. If you’d like to contribute,
please:

 1. Fork the repository.
 2. Create a new feature branch.
 3. Submit a pull request with a description of your changes.

For detailed information on how to contribute, please refer to CONTRIBUTING.md.