feat(watch): Wear OS companion app - UX surfaces + bridge client (#91-E, #91-F)

watch_app/lib/infrastructure/watch_bridge/native_watch_bridge_client.dart

@@ -0,0 +1,159 @@
+import 'package:flutter/services.dart';
+import 'package:watch_bridge_contract/watch_bridge_contract.dart';
+
+final class WatchBridgeConnectionEvent {
+  const WatchBridgeConnectionEvent({
+    required this.isReachable,
+    this.requestsResync = false,
+  });
+
+  final bool isReachable;
+  final bool requestsResync;
+}
+
+final class WatchCommandAckEvent {
+  const WatchCommandAckEvent({
+    required this.commandId,
+    required this.status,
+    required this.sessionId,
+    this.revisionAtAck,
+    this.reasonCode,
+  });
+
+  final String commandId;
+  final WatchCommandAck status;
+  final String sessionId;
+  final int? revisionAtAck;
+  final String? reasonCode;
+}
+
+abstract interface class NativeWatchBridgeClient {
+  Stream<WatchSessionProjection> get projections;
+
+  Stream<WatchCommandAckEvent> get acks;
+
+  Stream<WatchBridgeConnectionEvent> get connectionEvents;
+
+  Future<void> sendCommand(WatchCommandEnvelope command);
+
+  Future<void> requestResync();
+
+  Future<void> requestCapabilityRefresh();
+}
+
+final class MethodChannelNativeWatchBridgeClient
+    implements NativeWatchBridgeClient {
+  const MethodChannelNativeWatchBridgeClient({
+    MethodChannel methodChannel = const MethodChannel(_methodChannelName),
+    EventChannel projectionChannel = const EventChannel(
+      _projectionChannelName,
+    ),
+    EventChannel ackChannel = const EventChannel(_ackChannelName),
+    EventChannel connectionChannel = const EventChannel(
+      _connectionChannelName,
+    ),
+  }) : _methodChannel = methodChannel,
+       _projectionChannel = projectionChannel,
+       _ackChannel = ackChannel,
+       _connectionChannel = connectionChannel;
+
+  static const _methodChannelName = 'gametime.watch_bridge/methods';
+  static const _projectionChannelName = 'gametime.watch_bridge/projections';
+  static const _ackChannelName = 'gametime.watch_bridge/acks';
+  static const _connectionChannelName = 'gametime.watch_bridge/connection';
+
+  final MethodChannel _methodChannel;
+  final EventChannel _projectionChannel;
+  final EventChannel _ackChannel;
+  final EventChannel _connectionChannel;
+
+  @override
+  Stream<WatchSessionProjection> get projections {
+    return _projectionChannel
+        .receiveBroadcastStream()
+        .where((event) => event is Map)
+        .map((event) {
+          return WatchSessionProjection.fromJson(_stringObjectMap(event));
+        });
+  }
+
+  @override
+  Stream<WatchCommandAckEvent> get acks {
+    return _ackChannel
+        .receiveBroadcastStream()
+        .where((event) => event is Map)
+        .map((event) {
+          final json = _stringObjectMap(event);
+          return WatchCommandAckEvent(
+            commandId: _stringFromJson(json['commandId']),
+            status: _enumFromJson(
+              json['status'],
+              WatchCommandAck.values,
+              WatchCommandAck.rejectedPhoneBusy,
+            ),
+            sessionId: _stringFromJson(json['sessionId']),
+            revisionAtAck: _nullableIntFromJson(json['revisionAtAck']),
+            reasonCode: _nullableStringFromJson(json['reasonCode']),
+          );
+        });
+  }
+
+  @override
+  Stream<WatchBridgeConnectionEvent> get connectionEvents {
+    return _connectionChannel
+        .receiveBroadcastStream()
+        .where((event) => event is Map)
+        .map((event) {
+          final json = _stringObjectMap(event);
+          return WatchBridgeConnectionEvent(
+            isReachable: json['isReachable'] == true,
+            requestsResync: json['requestsResync'] == true,
+          );
+        });
+  }
+
+  @override
+  Future<void> sendCommand(WatchCommandEnvelope command) {
+    return _methodChannel.invokeMethod<void>('sendCommand', command.toJson());
+  }
+
+  @override
+  Future<void> requestCapabilityRefresh() {
+    return _methodChannel.invokeMethod<void>('requestCapabilityRefresh');
+  }
+
+  @override
+  Future<void> requestResync() {
+    return _methodChannel.invokeMethod<void>('requestResync');
+  }
+}
+
+Map<String, Object?> _stringObjectMap(Object? value) {
+  if (value is Map) {
+    return value.map((key, value) => MapEntry(key.toString(), value));
+  }
+  return const {};
+}
+
+String _stringFromJson(Object? value) {
+  return value is String ? value : '';
+}
+
+String? _nullableStringFromJson(Object? value) {
+  return value is String ? value : null;
+}
+
+int? _nullableIntFromJson(Object? value) {
+  return value is int ? value : value is num ? value.toInt() : null;
+}
+
+T _enumFromJson<T extends Enum>(Object? value, List<T> values, T fallback) {
+  if (value is String) {
+    for (final enumValue in values) {
+      if (enumValue.name == value) {
+        return enumValue;
+      }
+    }
+  }
+  return fallback;
+}