import 'package:flutter/material.dart';
import 'package:flutter_webrtc/flutter_webrtc.dart';
import 'package:uuid/uuid.dart';

import 'config/ice_servers.dart';
import 'controller/remote_controller.dart';
import 'utils/control_commands.dart';
import 'widgets/remote_touch_view.dart';

void main() {
  runApp(const MyApp());
}

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'WebRTC 控制端',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.blue),
        useMaterial3: true,
      ),
      home: const ControllerHome(),
    );
  }
}

class ControllerHome extends StatefulWidget {
  const ControllerHome({super.key});

  @override
  State<ControllerHome> createState() => _ControllerHomeState();
}

class _ControllerHomeState extends State<ControllerHome> {
  final _serverUrlController =
      TextEditingController(text: kDefaultSignalServer);
  final _deviceIdController = TextEditingController();
  final _targetController = TextEditingController(text: '981964879');

  RemoteController? _controller;
  RTCVideoRenderer? _renderer;

  /// 用于在任意位置（含回调中）弹出提示。
  final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();

  bool _connected = false;
  String _status = '状态: 已停止';
  String _stats = '';
  double _videoAspect = 16 / 9;

  @override
  void initState() {
    super.initState();
    _deviceIdController.text = 'controller_${const Uuid().v4().substring(0, 8)}';
  }

  @override
  void dispose() {
    _controller?.disconnect();
    _serverUrlController.dispose();
    _deviceIdController.dispose();
    _targetController.dispose();
    super.dispose();
  }

  void _setStatus(String status) => setState(() => _status = status);

  Future<void> _connect() async {
    final serverUrl = _serverUrlController.text.trim();
    final deviceId = _deviceIdController.text.trim();
    final target = _targetController.text.trim();

    if (serverUrl.isEmpty || deviceId.isEmpty || target.isEmpty) {
      _setStatus('请填写所有字段');
      return;
    }

    _setStatus('状态: 正在连接信令服务器...');

    _controller = RemoteController(
      serverUrl: serverUrl,
      deviceId: deviceId,
      targetDeviceId: target,
    );
    _controller!.onStatusChanged = _setStatus;
    _controller!.onConnectionEstablished = () {
      setState(() {
        _connected = true;
        _status = '状态: 已连接 - 远程控制中';
      });
    };
    _controller!.onDisconnected = () {
      setState(() => _connected = false);
      _setStatus('状态: 远端已断开');
    };
    _controller!.onIceDisconnected = (message) {
      _onIceDisconnected(message);
    };
    _controller!.onTargetOffline = (message) {
      _onTargetOffline(message);
    };
    _controller!.onRemoteStream = (renderer) {
      setState(() => _renderer = renderer);
      renderer.addListener(_onRendererUpdate);
    };
    _controller!.onStats = (stats) => setState(() => _stats = stats);

    _controller!.connect();
  }

  void _onRendererUpdate() {
    final w = _renderer?.value.width ?? 0;
    final h = _renderer?.value.height ?? 0;
    if (w > 0 && h > 0 && mounted) {
      setState(() => _videoAspect = w / h);
    }
  }

  /// ICE 断开：提示用户并自动返回连接设置面板。
  Future<void> _onIceDisconnected(String message) async {
    final scaffoldCtx = _scaffoldKey.currentState?.context;
    if (mounted && scaffoldCtx != null) {
      ScaffoldMessenger.of(scaffoldCtx).showSnackBar(
        SnackBar(
          content: Text(message),
          duration: const Duration(seconds: 3),
        ),
      );
    }
    await _disconnect();
  }

  /// 目标被控端不在线：提示用户并复位到连接设置面板。
  Future<void> _onTargetOffline(String message) async {
    final scaffoldCtx = _scaffoldKey.currentState?.context;
    if (mounted && scaffoldCtx != null) {
      ScaffoldMessenger.of(scaffoldCtx).showSnackBar(
        SnackBar(
          content: Text(message),
          duration: const Duration(seconds: 3),
        ),
      );
    }
    setState(() => _connected = false);
  }

  Future<void> _disconnect() async {
    await _controller?.disconnect();
    _controller = null;
    _renderer?.removeListener(_onRendererUpdate);
    setState(() {
      _connected = false;
      _renderer = null;
      _status = '状态: 已停止';
      _stats = '';
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      key: _scaffoldKey,
      appBar: AppBar(title: const Text('WebRTC 控制端')),
      body: _connected ? _buildControlPanel() : _buildSetupPanel(),
    );
  }

  Widget _buildSetupPanel() {
    return SingleChildScrollView(
      padding: const EdgeInsets.all(24),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          const Text(
            'WebRTC 控制端',
            style: TextStyle(fontSize: 24, fontWeight: FontWeight.bold),
          ),
          const SizedBox(height: 24),
          const Text('信令服务器地址:', style: TextStyle(fontSize: 14)),
          TextField(
            controller: _serverUrlController,
            decoration: const InputDecoration(
              hintText: 'ws://175.178.213.60:8088/ws/signal',
            ),
          ),
          const SizedBox(height: 16),
          const Text('本机设备ID:', style: TextStyle(fontSize: 14)),
          TextField(
            controller: _deviceIdController,
            decoration: const InputDecoration(hintText: '设备ID'),
          ),
          const SizedBox(height: 16),
          const Text('目标被控设备ID:', style: TextStyle(fontSize: 14)),
          TextField(
            controller: _targetController,
            decoration: const InputDecoration(hintText: '被控端设备ID'),
          ),
          const SizedBox(height: 24),
          Text(
            _status,
            style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
          ),
          const SizedBox(height: 24),
          SizedBox(
            width: double.infinity,
            child: ElevatedButton(
              onPressed: _connect,
              child: const Text('连接被控设备'),
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildControlPanel() {
    return Stack(
      children: [
        Container(color: Colors.black),
        if (_renderer != null)
          Center(
            child: AspectRatio(
              aspectRatio: _videoAspect,
              child: Stack(
                fit: StackFit.expand,
                children: [
                  RTCVideoView(
                    _renderer!,
                    objectFit:
                        RTCVideoViewObjectFit.RTCVideoViewObjectFitContain,
                  ),
                  RemoteTouchView(
                    onTouch: (x, y) => _controller
                        ?.sendControlCommand(ControlCommands.touch(x, y)),
                    onSwipe: (x1, y1, x2, y2, d) => _controller
                        ?.sendControlCommand(
                            ControlCommands.swipe(x1, y1, x2, y2, d)),
                    onKey: (k, a) => _controller
                        ?.sendControlCommand(ControlCommands.key(k, a)),
                    onLongPress: (x, y) => _controller
                        ?.sendControlCommand(ControlCommands.longPress(x, y)),
                  ),
                ],
              ),
            ),
          ),
        Positioned(
          top: 0,
          left: 0,
          child: Container(
            color: Colors.black54,
            padding: const EdgeInsets.all(8),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  _status,
                  style: const TextStyle(color: Colors.white),
                ),
                Text(
                  _stats,
                  style:
                      const TextStyle(color: Colors.white, fontSize: 12),
                ),
              ],
            ),
          ),
        ),
        Positioned(
          bottom: 16,
          right: 16,
          child: FloatingActionButton(
            onPressed: _disconnect,
            tooltip: '断开连接',
            child: const Icon(Icons.close),
          ),
        ),
      ],
    );
  }
}