// js_bridge.dart
import 'dart:async';
import 'dart:convert';
import 'package:webview_flutter/webview_flutter.dart';

typedef JSBridgeHandler = Future<dynamic> Function(dynamic data);

class ATJSBridge {
  final Map<String, JSBridgeHandler> _handlers = {};
  late WebViewController _controller;
  final Map<String, Completer<dynamic>> _pendingCalls = {};
  int _callId = 0;

  // 初始化桥梁
  void initialize(WebViewController controller) {
    _controller = controller;
  }

  // 注册处理方法
  void registerHandler(String name, JSBridgeHandler handler) {
    _handlers[name] = handler;
  }

  // 移除处理方法
  void removeHandler(String name) {
    _handlers.remove(name);
  }

  // 调用JS方法
// 调用JS方法
  Future<dynamic> callHandler(String handlerName, dynamic data) async {
    final callId = 'flutter_${_callId++}_${DateTime.now().millisecondsSinceEpoch}';
    final completer = Completer<dynamic>();
    _pendingCalls[callId] = completer;

    final message = {
      'type': 'call',
      'handlerName': handlerName,
      'data': data,
      'callId': callId,
    };

    try {
      await _controller.runJavaScript('''
      if (window.__flutterBridge && typeof window.__flutterBridge.receiveMessage === 'function') {
        window.__flutterBridge.receiveMessage(${jsonEncode(message)});
      } else if (window.JSBridge) {
        window.JSBridge.postMessage(${jsonEncode(message)});
      } else {
        console.error('Flutter bridge not initialized');
      }
    ''');
    } catch (e) {
      _pendingCalls.remove(callId);
      completer.completeError(e);
    }

    // 设置超时
    return completer.future.timeout(const Duration(seconds: 10), onTimeout: () {
      _pendingCalls.remove(callId);
      throw TimeoutException('JS call timeout');
    });
  }

  // 处理来自JS的消息
  Future<void> handleMessage(String message) async {
    try {
      final Map<String, dynamic> data = jsonDecode(message);
      final type = data['type'] as String?;

      switch (type) {
        case 'call':
          await _handleJSCall(data);
          break;
        case 'response':
          await _handleJSResponse(data);
          break;
        default:
          print('Unknown message type: $type');
      }
    } catch (e) {
      print('Error handling message: $e');
    }
  }

  // 处理JS调用的方法
  Future<void> _handleJSCall(Map<String, dynamic> data) async {
    final handlerName = data['handlerName'] as String?;
    final callId = data['callId'] as String?;
    final messageData = data['data'];

    if (handlerName == null || callId == null) return;

    dynamic result;
    String? error;

    try {
      final handler = _handlers[handlerName];
      if (handler != null) {
        result = await handler(messageData);
      } else {
        error = 'Handler "$handlerName" not found';
      }
    } catch (e) {
      error = e.toString();
    }

    // 发送响应回JS
    final response = {
      'type': 'response',
      'callId': callId,
      'data': result,
      'error': error,
    };

    await _controller.runJavaScript('''
      if (window.__flutterBridge && window.__flutterBridge.receiveResponse) {
        window.__flutterBridge.receiveResponse(${jsonEncode(response)});
      }
    ''');
  }

  // 处理JS的响应
  Future<void> _handleJSResponse(Map<String, dynamic> data) async {
    final callId = data['callId'] as String?;
    if (callId == null) return;

    final completer = _pendingCalls[callId];
    if (completer == null) return;

    if (data['error'] != null) {
      completer.completeError(Exception(data['error']));
    } else {
      completer.complete(data['data']);
    }

    _pendingCalls.remove(callId);
  }
}