import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:flutter_webrtc/flutter_webrtc.dart';

import 'config/ice_servers.dart';
import 'controller/remote_controller.dart';
import 'utils/control_commands.dart';
import 'utils/device_utils.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 CupertinoApp(
      title: 'WebRTC 控制端',
      theme: const CupertinoThemeData(primaryColor: CupertinoColors.activeBlue),
      home: const ControllerHome(),
    );
  }
}

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

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

class _ControllerHomeState extends State<ControllerHome> {
  /// 与 Windows 原生窗口通信的通道（用于按视频比例调整窗口高度）。
  static const MethodChannel _windowChannel = MethodChannel('app/window');

  /// 记录上一次已应用的视频宽高比，避免重复调整窗口。
  double _lastResizedAspect = 0;

  final _serverUrlController = TextEditingController(
    text: kDefaultSignalServer,
  );
  final _deviceIdController = TextEditingController();
  final _targetController = TextEditingController(text: '981964879');

  RemoteController? _controller;
  RTCVideoRenderer? _renderer;

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

  /// 分辨率预设：width 为长边像素；0 表示被控端原生分辨率；
  /// height 传 0（由被控端按屏幕宽高比计算），fps 传 0（沿用当前帧率）。
  int _selectedResolution = 0;
  final List<Map<String, Object>> _resolutionOptions = const [
    {'label': '原始', 'width': 0, 'height': 0, 'fps': 0},
    {'label': '1080P', 'width': 1920, 'height': 0, 'fps': 0},
    {'label': '720P', 'width': 1280, 'height': 0, 'fps': 0},
    {'label': '480P', 'width': 854, 'height': 0, 'fps': 0},
  ];

  @override
  void initState() {
    super.initState();
    _initDeviceId();
  }

  /// 异步获取设备标识并填入设备ID输入框（非系统签名，使用兜底方案）。
  Future<void> _initDeviceId() async {
    final id = await DeviceUtils.getSerialNumber();
    if (mounted) {
      setState(() => _deviceIdController.text = id);
    }
  }

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

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

  /// 以 iOS 风格弹窗提示用户（替代原 Material 的 SnackBar）。
  void _showAlert(String message) {
    if (!mounted) return;
    showCupertinoDialog<void>(
      context: context,
      builder: (ctx) => CupertinoAlertDialog(
        content: Text(message),
        actions: [
          CupertinoDialogAction(
            child: const Text('确定'),
            onPressed: () => Navigator.of(ctx).pop(),
          ),
        ],
      ),
    );
  }

  Future<void> _showAuthDialog() 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;
    }

    String selectedType = 'CODE';
    final valueController = TextEditingController();

    await showCupertinoDialog<void>(
      context: context,
      builder: (ctx) => StatefulBuilder(
        builder: (ctx, setDialogState) => CupertinoAlertDialog(
          title: const Text('连接鉴权'),
          content: Column(
            children: [
              const SizedBox(height: 12),
              CupertinoSegmentedControl<String>(
                children: const {
                  'CODE': Padding(
                    padding: EdgeInsets.symmetric(horizontal: 8),
                    child: Text('动态验证码'),
                  ),
                  'PASSWORD': Padding(
                    padding: EdgeInsets.symmetric(horizontal: 8),
                    child: Text('固定密码'),
                  ),
                },
                groupValue: selectedType,
                onValueChanged: (v) => setDialogState(() => selectedType = v),
              ),
              const SizedBox(height: 12),
              CupertinoTextField(
                controller: valueController,
                placeholder: '请输入验证码或密码',
                obscureText: true,
                padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
              ),
            ],
          ),
          actions: [
            CupertinoDialogAction(
              child: const Text('取消'),
              onPressed: () => Navigator.of(ctx).pop(),
            ),
            CupertinoDialogAction(
              child: const Text('连接'),
              onPressed: () {
                final val = valueController.text.trim();
                if (val.isEmpty) {
                  _showAlert('请输入验证码或密码');
                  return;
                }
                Navigator.of(ctx).pop();
                _connect(authType: selectedType, authValue: val);
              },
            ),
          ],
        ),
      ),
    );
  }

  Future<void> _connect({required String authType, required String authValue}) 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,
      authType: authType,
      authValue: authValue,
    );
    _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!.onConnectionRejected = (message) {
      _onConnectionRejected(message);
    };
    _controller!.onRemoteStream = (renderer) {
      setState(() => _renderer = renderer);
      renderer.addListener(_onRendererUpdate);
    };
    _controller!.onStats = (stats) => setState(() => _stats = stats);

    _controller!.connect(authType: authType, authValue: authValue);
  }

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

  /// Windows 端：保持窗口宽度不变，按视频宽高比调整窗口高度；
  /// 若高度超出屏幕，由原生端改为合适的窗口大小。
  void _resizeWindowToAspect(double aspect) {
    if (kIsWeb || defaultTargetPlatform != TargetPlatform.windows) return;
    if (aspect <= 0) return;
    if ((aspect - _lastResizedAspect).abs() < 0.001) return;
    _lastResizedAspect = aspect;
    _windowChannel.invokeMethod('resizeToVideoAspect', aspect);
  }

  /// ICE 断开：提示用户并自动返回连接设置面板。
  Future<void> _onIceDisconnected(String message) async {
    _showAlert(message);
    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 {
    _showAlert(message);
    setState(() => _connected = false);
  }

  /// 被控端拒绝连接请求：提示用户并复位到连接设置面板。
  Future<void> _onConnectionRejected(String message) async {
    _showAlert(message);
    setState(() => _connected = false);
  }

  /// 弹出分辨率选择菜单（iOS 风格 ActionSheet）。
  void _showResolutionMenu() {
    showCupertinoModalPopup<void>(
      context: context,
      builder: (ctx) => CupertinoActionSheet(
        title: const Text('切换分辨率'),
        actions: [
          for (int i = 0; i < _resolutionOptions.length; i++)
            CupertinoActionSheetAction(
              onPressed: () {
                Navigator.of(ctx).pop();
                setState(() => _selectedResolution = i);
                final o = _resolutionOptions[i];
                _controller?.sendResolutionChange(
                  o['width'] as int,
                  o['height'] as int,
                  o['fps'] as int,
                );
              },
              child: Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  if (i == _selectedResolution) ...[
                    const Icon(CupertinoIcons.check_mark,
                        size: 18, color: CupertinoColors.activeBlue),
                    const SizedBox(width: 8),
                  ],
                  Text(_resolutionOptions[i]['label'] as String),
                ],
              ),
            ),
        ],
        cancelButton: CupertinoActionSheetAction(
          isDefaultAction: true,
          onPressed: () => Navigator.of(ctx).pop(),
          child: const Text('取消'),
        ),
      ),
    );
  }

  Future<void> _disconnect() async {
    await _controller?.disconnect();
    _controller = null;
    _renderer?.removeListener(_onRendererUpdate);
    _lastResizedAspect = 0;
    setState(() {
      _connected = false;
      _renderer = null;
      _status = '状态: 已停止';
      _stats = '';
    });
  }

  @override
  Widget build(BuildContext context) {
    return CupertinoPageScaffold(
      // 控制模式（已连接）下隐藏导航栏，避免其半透明浮层遮挡顶部的
      // 状态/统计信息浮层；连接设置面板再显示标题栏。
      navigationBar: _connected
          ? null
          : const CupertinoNavigationBar(
              middle: Text('WebRTC 控制端'),
            ),
      child: _connected ? _buildControlPanel() : _buildSetupPanel(),
    );
  }

  Widget _buildSetupPanel() {
    return SafeArea(
      child: 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)),
            const SizedBox(height: 8),
            CupertinoTextField(
              controller: _serverUrlController,
              placeholder: 'ws://175.178.213.60:8088/ws/signal',
              padding: const EdgeInsets.symmetric(vertical: 12, horizontal: 12),
            ),
            const SizedBox(height: 16),
            const Text('本机设备ID:', style: TextStyle(fontSize: 14)),
            const SizedBox(height: 8),
            CupertinoTextField(
              controller: _deviceIdController,
              placeholder: '设备ID',
              padding: const EdgeInsets.symmetric(vertical: 12, horizontal: 12),
            ),
            const SizedBox(height: 16),
            const Text('目标被控设备ID:', style: TextStyle(fontSize: 14)),
            const SizedBox(height: 8),
            CupertinoTextField(
              controller: _targetController,
              placeholder: '被控端设备ID',
              padding: const EdgeInsets.symmetric(vertical: 12, horizontal: 12),
            ),
            const SizedBox(height: 24),
            Text(
              _status,
              style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
            ),
            const SizedBox(height: 24),
            SizedBox(
              width: double.infinity,
              child: CupertinoButton.filled(
                onPressed: _showAuthDialog,
                child: const Text('连接被控设备'),
              ),
            ),
          ],
        ),
      ),
    );
  }

  /// 右上角浮动顶部菜单栏：整合「分辨率切换」与「断开连接」。
  Widget _buildTopMenuBar() {
    return Container(
      decoration: BoxDecoration(
        color: Colors.black54,
        borderRadius: BorderRadius.circular(22),
      ),
      padding: const EdgeInsets.symmetric(horizontal: 4),
      child: Row(
        mainAxisSize: MainAxisSize.min,
        children: [
          // 分辨率菜单按钮：显示当前分辨率标签
          CupertinoButton(
            padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
            onPressed: _showResolutionMenu,
            child: Row(
              mainAxisSize: MainAxisSize.min,
              children: [
                const Icon(CupertinoIcons.slider_horizontal_3,
                    color: CupertinoColors.white, size: 20),
                const SizedBox(width: 6),
                Text(
                  _resolutionOptions[_selectedResolution]['label'] as String,
                  style: const TextStyle(
                    color: CupertinoColors.white,
                    fontSize: 14,
                  ),
                ),
              ],
            ),
          ),
          // 分隔线
          Container(
            width: 1,
            height: 22,
            color: CupertinoColors.white.withValues(alpha: 0.3),
          ),
          // 断开连接按钮
          CupertinoButton(
            padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
            onPressed: _disconnect,
            child: const Icon(
              CupertinoIcons.xmark_circle_fill,
              color: CupertinoColors.destructiveRed,
              size: 24,
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildControlPanel() {
    return SafeArea(
      // 仅保留顶部安全区（避开系统状态栏），底部/左右保持全屏，
      // 以便右下角的断开按钮贴近屏幕边缘。
      top: true,
      bottom: false,
      left: false,
      right: false,
      child: 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(
                    // 禁用离散的 TOUCH/SWIPE/LONG_PRESS 指令，改用实时的 onMotionEvent 以解决重复操作问题。
                    // 原始的动作流已包含完整的触摸过程，被控端系统会自动识别单击、滑动和长按。
                    onTouch: (x, y) {},
                    onSwipe: (x1, y1, x2, y2, d) {},
                    onLongPress: (x, y) {},
                    onKey: (k, a) => _controller?.sendControlCommand(
                      ControlCommands.key(k, a),
                    ),
                    onMotionEvent: (a, x, y) => _controller?.sendControlCommand(
                      ControlCommands.motionEvent(a, 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(
          top: 8,
          right: 8,
          child: _buildTopMenuBar(),
        ),
      ],
      ),
    );
  }
}