import 'dart:async';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:video_player/video_player.dart';
import '../providers/auth_provider.dart';
import '../providers/settings_provider.dart';
import '../services/chat_service.dart';

class PlayerPage extends StatefulWidget {
  final String title;
  final String rtmpUrl;
  final String roomId;

  const PlayerPage({
    Key? key,
    required this.title,
    required this.rtmpUrl,
    required this.roomId,
  }) : super(key: key);

  @override
  _PlayerPageState createState() => _PlayerPageState();
}

class _PlayerPageState extends State<PlayerPage> {
  late VideoPlayerController _controller;
  final ChatService _chatService = ChatService();
  final TextEditingController _msgController = TextEditingController();
  final List<ChatMessage> _messages = [];
  final List<Widget> _danmakus = [];
  
  bool _isError = false;
  String? _errorMessage;

  @override
  void initState() {
    super.initState();
    _initializePlayer();
    _initializeChat();
  }

  void _initializePlayer() async {
    _controller = VideoPlayerController.networkUrl(Uri.parse(widget.rtmpUrl));
    try {
      await _controller.initialize();
      _controller.play();
      if (mounted) setState(() {});
    } catch (e) {
      if (mounted) setState(() { _isError = true; _errorMessage = e.toString(); });
    }
  }

  void _initializeChat() {
    final settings = context.read<SettingsProvider>();
    final auth = context.read<AuthProvider>();
    
    // 使用真实用户名建立连接
    final currentUsername = auth.username ?? "Guest_${widget.roomId}";
    _chatService.connect(settings.baseUrl, widget.roomId, currentUsername);

    _chatService.messages.listen((msg) {
      if (mounted) {
        setState(() {
          _messages.insert(0, msg);
          if (!msg.isHistory && (msg.type == "chat" || msg.type == "danmaku")) {
            _addDanmaku(msg.content);
          }
        });
      }
    });
  }

  void _addDanmaku(String text) {
    final key = UniqueKey();
    final top = 20.0 + (DateTime.now().millisecondsSinceEpoch % 6) * 30.0; 
    
    final danmaku = _DanmakuItem(
      key: key,
      text: text,
      top: top,
      onFinished: () {
        if (mounted) setState(() => _danmakus.removeWhere((w) => w.key == key));
      },
    );

    setState(() => _danmakus.add(danmaku));
  }

  void _sendMsg() {
    if (_msgController.text.isNotEmpty) {
      final auth = context.read<AuthProvider>();
      _chatService.sendMessage(_msgController.text, auth.username ?? "Anonymous", widget.roomId);
      _msgController.clear();
    }
  }

  @override
  void dispose() {
    _controller.dispose();
    _chatService.dispose();
    _msgController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    bool isWide = MediaQuery.of(context).size.width > 900;

    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      body: isWide ? _buildWideLayout() : _buildMobileLayout(),
    );
  }

  // 宽屏布局：左右分栏
  Widget _buildWideLayout() {
    return Row(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        // 左侧视频区 (占比 75%)
        Expanded(
          flex: 3,
          child: Container(
            color: Colors.black,
            child: _buildVideoWithDanmaku(),
          ),
        ),
        // 右侧聊天区 (占比 25%)
        Container(
          width: 350,
          decoration: BoxDecoration(
            border: Border(left: BorderSide(color: Theme.of(context).dividerColor)),
          ),
          child: _buildChatSection(),
        ),
      ],
    );
  }

  // 移动端布局：上下堆叠
  Widget _buildMobileLayout() {
    return Column(
      children: [
        // 上方视频区
        Container(
          color: Colors.black,
          width: double.infinity,
          height: 250,
          child: _buildVideoWithDanmaku(),
        ),
        // 下方聊天区
        Expanded(child: _buildChatSection()),
      ],
    );
  }

  // 抽离视频播放器与弹幕组件
  Widget _buildVideoWithDanmaku() {
    return Stack(
      children: [
        Center(
          child: _isError
              ? Text("Error: $_errorMessage", style: TextStyle(color: Colors.white))
              : _controller.value.isInitialized
                  ? AspectRatio(
                      aspectRatio: _controller.value.aspectRatio,
                      child: VideoPlayer(_controller),
                    )
                  : CircularProgressIndicator(),
        ),
        // 弹幕层使用 ClipRect 裁剪，防止飘出视频区域
        ClipRect(
          child: Stack(children: _danmakus),
        ),
      ],
    );
  }

  // 抽离聊天区域组件
  Widget _buildChatSection() {
    return Column(
      children: [
        Container(
          padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
          color: Theme.of(context).colorScheme.surfaceVariant,
          child: Row(
            children: [
              Icon(Icons.chat_bubble_outline, size: 16),
              SizedBox(width: 8),
              Text("Live Chat", style: TextStyle(fontWeight: FontWeight.bold)),
            ],
          ),
        ),
        Expanded(
          child: ListView.builder(
            reverse: true,
            padding: EdgeInsets.all(8),
            itemCount: _messages.length,
            itemBuilder: (context, index) {
              final m = _messages[index];
              return Padding(
                padding: const EdgeInsets.symmetric(vertical: 4.0),
                child: RichText(
                  text: TextSpan(
                    style: TextStyle(color: Theme.of(context).textTheme.bodyMedium?.color),
                    children: [
                      TextSpan(
                        text: "${m.username}: ",
                        style: TextStyle(fontWeight: FontWeight.bold, color: m.type == "system" ? Colors.blue : Theme.of(context).colorScheme.primary),
                      ),
                      TextSpan(text: m.content),
                    ],
                  ),
                ),
              );
            },
          ),
        ),
        Divider(height: 1),
        Padding(
          padding: const EdgeInsets.all(8.0),
          child: Row(
            children: [
              Expanded(
                child: TextField(
                  controller: _msgController,
                  decoration: InputDecoration(
                    hintText: "Send a message...",
                    border: OutlineInputBorder(borderRadius: BorderRadius.circular(20)),
                    contentPadding: EdgeInsets.symmetric(horizontal: 16, vertical: 8),
                  ),
                  onSubmitted: (_) => _sendMsg(),
                ),
              ),
              IconButton(icon: Icon(Icons.send, color: Theme.of(context).colorScheme.primary), onPressed: _sendMsg),
            ],
          ),
        ),
      ],
    );
  }
}

class _DanmakuItem extends StatefulWidget {
  final String text;
  final double top;
  final VoidCallback onFinished;

  const _DanmakuItem({Key? key, required this.text, required this.top, required this.onFinished}) : super(key: key);

  @override
  __DanmakuItemState createState() => __DanmakuItemState();
}

class __DanmakuItemState extends State<_DanmakuItem> with SingleTickerProviderStateMixin {
  late AnimationController _animationController;
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _animationController = AnimationController(duration: const Duration(seconds: 10), vsync: this);
    
    // 使用相对位置：从右向左
    _animation = Tween<double>(begin: 1.0, end: -0.5).animate(_animationController);
    
    _animationController.forward().then((_) => widget.onFinished());
  }

  @override
  void dispose() {
    _animationController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _animation,
      builder: (context, child) {
        return Positioned(
          top: widget.top,
          // left 使用 MediaQuery 获取屏幕宽度进行动态计算
          left: MediaQuery.of(context).size.width * _animation.value,
          child: Text(
            widget.text,
            style: TextStyle(
              color: Colors.white,
              fontWeight: FontWeight.bold,
              fontSize: 18,
              shadows: [Shadow(blurRadius: 4, color: Colors.black, offset: Offset(1, 1))],
            ),
          ),
        );
      },
    );
  }
}