Refactor SpinifyCommandMixin error handling and connection logic

lib/spinify.dart

@@ -6,7 +6,7 @@ export 'src/model/command.dart';
 export 'src/model/config.dart';
 export 'src/model/history.dart';
 export 'src/model/jwt.dart';
-export 'src/model/metrics.dart';
+export 'src/model/metric.dart' show SpinifyMetrics;
 export 'src/model/presence_stats.dart';
 export 'src/model/pushes_stream.dart';
 export 'src/model/reply.dart';

lib/src/model/metric.dart

@@ -0,0 +1,177 @@
+import 'package:meta/meta.dart';
+
+import 'state.dart';
+
+/*
+/// Subscription count
+/// - total
+/// - unsubscribed
+/// - subscribing
+/// - subscribed
+///
+/// {@category Metrics}
+/// {@category Entity}
+typedef SpinifySubscriptionCount = ({
+  int total,
+  int unsubscribed,
+  int subscribing,
+  int subscribed
+}); */
+
+/// {@template metrics}
+/// Metrics of Spinify client.
+/// {@endtemplate}
+///
+/// {@category Metrics}
+sealed class SpinifyMetrics implements Comparable<SpinifyMetrics> {
+  /// {@macro metrics}
+  const SpinifyMetrics();
+
+  /// Timestamp of the metrics.
+  abstract final DateTime timestamp;
+
+  /// The time when the client was initialized.
+  abstract final DateTime initializedAt;
+
+  /// Next Command ID.
+  /// Incremented after each command.
+  abstract final int commandId;
+
+  /// The current state of the client.
+  abstract final SpinifyState state;
+
+  /*
+  /// The total number of messages & size of bytes sent.
+  final ({BigInt count, BigInt size}) transferred;
+
+  /// The total number of messages & size of bytes received.
+  final ({BigInt count, BigInt size}) received;
+
+  /// The number of subscriptions.
+  final ({
+    SpinifySubscriptionCount client,
+    SpinifySubscriptionCount server
+  }) subscriptions;
+
+  /// The average speed of the request/response in milliseconds.
+  /// - min - minimum speed
+  /// - avg - average speed
+  /// - max - maximum speed
+  final ({int min, int avg, int max}) speed;
+
+  /// Is refresh active.
+  final bool isRefreshActive;
+ */
+
+  /// The total number of successful connections.
+  abstract final int connects;
+
+  /// The time of the last connect.
+  abstract final DateTime? lastConnectAt;
+
+  /// Last connected URL.
+  /// Used for reconnecting after connection lost.
+  /// If null, then client is not connected or interractively disconnected.
+  abstract final String? reconnectUrl;
+
+  /// Number of reconnect attempts.
+  /// If null, then client is not connected yet or interractively disconnected.
+  abstract final int? reconnectAttempts;
+
+  /// Next reconnect time in case of connection lost.
+  abstract final DateTime? nextReconnectAt;
+
+  /// The total number of times the connection has been disconnected.
+  abstract final int disconnects;
+
+  /// The time of the last disconnect.
+  abstract final DateTime? lastDisconnectAt;
+
+  /// Convert metrics to JSON.
+  Map<String, Object?> toJson() => <String, Object?>{};
+
+  @override
+  int compareTo(SpinifyMetrics other) => timestamp.compareTo(other.timestamp);
+
+  @override
+  String toString() => 'SpinifyMetrics{}';
+}
+
+@internal
+@immutable
+final class SpinifyMetrics$Immutable extends SpinifyMetrics {
+  const SpinifyMetrics$Immutable();
+
+  @override
+  DateTime get timestamp => throw UnimplementedError();
+
+  @override
+  DateTime get initializedAt => throw UnimplementedError();
+
+  @override
+  int get commandId => throw UnimplementedError();
+
+  @override
+  SpinifyState get state => throw UnimplementedError();
+
+  @override
+  int get connects => throw UnimplementedError();
+
+  @override
+  DateTime? get lastConnectAt => throw UnimplementedError();
+
+  @override
+  String? get reconnectUrl => throw UnimplementedError();
+
+  @override
+  int? get reconnectAttempts => throw UnimplementedError();
+
+  @override
+  DateTime? get nextReconnectAt => throw UnimplementedError();
+
+  @override
+  int get disconnects => throw UnimplementedError();
+
+  @override
+  DateTime? get lastDisconnectAt => throw UnimplementedError();
+}
+
+@internal
+final class SpinifyMetrics$Mutable extends SpinifyMetrics {
+  SpinifyMetrics$Mutable();
+
+  @override
+  DateTime get timestamp => DateTime.now();
+
+  @override
+  final DateTime initializedAt = DateTime.now();
+
+  @override
+  int commandId = 1;
+
+  @override
+  SpinifyState state = SpinifyState$Disconnected();
+
+  @override
+  int connects = 0;
+
+  @override
+  DateTime? lastConnectAt;
+
+  @override
+  String? reconnectUrl;
+
+  @override
+  int? reconnectAttempts;
+
+  @override
+  DateTime? nextReconnectAt;
+
+  @override
+  int disconnects = 0;
+
+  @override
+  DateTime? lastDisconnectAt;
+
+  SpinifyMetrics$Immutable freeze() => const SpinifyMetrics$Immutable();
+}

lib/src/model/spinify_interface.dart

@@ -5,7 +5,7 @@ import 'dart:async';
 import 'channel_push.dart';
 import 'config.dart';
 import 'history.dart';
-import 'metrics.dart';
+import 'metric.dart';
 import 'presence_stats.dart';
 import 'pushes_stream.dart';
 import 'state.dart';