add facebook

lib/facebook/facebook_service.dart

@@ -0,0 +1,84 @@
+import 'dart:developer' as developer;
+
+import 'package:facebook_app_events/facebook_app_events.dart';
+import 'package:flutter/foundation.dart';
+
+class FacebookInitConfig {
+  final String applicationId;
+  final String? secret;
+
+  const FacebookInitConfig({required this.applicationId, this.secret});
+
+  static FacebookInitConfig? fromRemote(dynamic source) {
+    if (source is! Map) return null;
+
+    final applicationId = source['m']?.toString().trim();
+    if (applicationId == null || applicationId.length < 5) return null;
+
+    return FacebookInitConfig(
+      applicationId: applicationId,
+      secret: source['n']?.toString().trim(),
+    );
+  }
+}
+
+class FacebookService {
+  FacebookService._();
+
+  static final FacebookService instance = FacebookService._();
+
+  final FacebookAppEvents _events = FacebookAppEvents();
+  bool _inited = false;
+  String? _applicationId;
+
+  bool get inited => _inited;
+
+  Future<void> init(FacebookInitConfig config) async {
+    if (_inited && _applicationId == config.applicationId) {
+      developer.log('[Facebook] already inited', name: 'Facebook');
+      return;
+    }
+
+    try {
+      await _events.setAutoLogAppEventsEnabled(false);
+      await _events.setAdvertiserTracking(enabled: true, collectId: true);
+      await _events.activateApp(applicationId: config.applicationId);
+
+      _applicationId = config.applicationId;
+      _inited = true;
+      developer.log(
+        '[Facebook] inited appId=${config.applicationId}',
+        name: 'Facebook',
+      );
+    } catch (e, st) {
+      developer.log(
+        '[Facebook] init error: $e',
+        name: 'Facebook',
+        stackTrace: st,
+      );
+    }
+  }
+
+  Future<void> initFromRemote(dynamic source) async {
+    final config = FacebookInitConfig.fromRemote(source);
+    if (config == null) return;
+    await init(config);
+  }
+
+  Future<void> initWithParams(Map<String, dynamic> params) async {
+    await initFromRemote(params);
+  }
+
+  Future<void> trackEvent(
+    String eventName, [
+    Map<String, dynamic>? params,
+  ]) async {
+    if (!_inited || eventName.isEmpty) return;
+
+    try {
+      await _events.logEvent(name: eventName, parameters: params);
+    } catch (e) {
+      debugPrint('[Facebook] track event failed: $e');
+    }
+  }
+}