import 'dart:convert';
import 'package:bonsoir/bonsoir.dart';
import 'package:flutter/material.dart';
import 'package:mobile_scanner/mobile_scanner.dart';
import 'package:playwith_core/playwith_core.dart'; // Core (AvatarWidget, NetworkManager 등)
import 'package:playwith_game_quiz/quiz_game.dart';
import 'package:qr_flutter/qr_flutter.dart';

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

  @override
  State<LobbyScreen> createState() => _LobbyScreenState();
}

class _LobbyScreenState extends State<LobbyScreen> {
  final _net = NetworkManager();
  final List<String> _logs = [];
  final ScrollController _scrollController = ScrollController();

  @override
  void initState() {
    super.initState();
    
    // 로그 리스너
    _net.logStream.listen((log) {
      if (!mounted) return;
      setState(() {
        _logs.add(log);
        if (_logs.length > 100) _logs.removeAt(0);
      });
      WidgetsBinding.instance.addPostFrameCallback((_) {
        if (_scrollController.hasClients) {
          _scrollController.animateTo(
            _scrollController.position.maxScrollExtent,
            duration: const Duration(milliseconds: 200),
            curve: Curves.easeOut,
          );
        }
      });
    });

    // 게임 시작 신호 감지
    _net.messageStream.listen((data) {
      if (data['type'] == 'GAME_START') {
        final String gameId = data['gameId'];
        if (gameId == 'quiz_ox') {
          _startGameAndNavigate(QuizGame());
        }
      }
    });
  }

  void _startGameAndNavigate(BaseGame game) {
    if (!mounted) return;
    game.onStart();

    Navigator.push(
      context,
      MaterialPageRoute(builder: (context) {
        Widget gameView;
        if (_net.role == NetworkRole.host) {
          gameView = game.buildHostView(context);
        } else {
          gameView = game.buildGuestView(context);
        }

        // 게임 위 채팅 오버레이
        return Stack(
          children: [
            gameView,
            const SafeArea(child: GameChatOverlay()),
          ],
        );
      }),
    );
  }

  @override
  Widget build(BuildContext context) {
    return ListenableBuilder(
      listenable: _net,
      builder: (context, child) {
        return Scaffold(
          appBar: AppBar(
            title: const Text('대기실'),
            centerTitle: true,
            actions: [
              // 연결된 상태라면 나가기 버튼 표시
              if (_net.role != NetworkRole.none)
                IconButton(
                  icon: const Icon(Icons.exit_to_app, color: Colors.red),
                  tooltip: "나가기",
                  onPressed: () => _net.stopNetwork(),
                )
            ],
          ),
          body: Column(
            children: [
              // 메인 바디 (연결 상태에 따라 분기)
              Expanded(flex: 3, child: _buildMainBody()),
              
              const Divider(thickness: 1, height: 1),
              
              // 하단 디버그 로그 (개발용)
              _buildDebugConsole(),
            ],
          ),
        );
      },
    );
  }

  // [Main Body] 상태에 따라 초기화면 vs 대기실 화면 분기
  Widget _buildMainBody() {
    // 1. 아직 연결 안 됨 (초기 화면)
    if (_net.role == NetworkRole.none) {
      return _buildInitView();
    }

    // 2. 연결됨 (대기실 - 방장/참가자 통합 UI)
    return _buildLobbyView();
  }

  // ------------------------------------------------------------------------
  // 1. 초기 화면 (방 만들기 / 찾기)
  // ------------------------------------------------------------------------
  Widget _buildInitView() {
    return Center(
      child: SingleChildScrollView(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const Text("게임을 시작해볼까요?", style: TextStyle(fontSize: 24, fontWeight: FontWeight.bold)),
            const SizedBox(height: 40),
            
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                _BigButton(
                  title: "방 만들기\n(Host)",
                  color: Colors.blue[100]!,
                  icon: Icons.add_home_work,
                  onTap: () {
                    _net.startHosting("${_net.me.nickname}의 방");
                    // 방장은 방 만들자마자 QR 팝업
                    Future.delayed(const Duration(milliseconds: 500), () {
                      if (mounted && _net.role == NetworkRole.host) _showHostQRDialog();
                    });
                  },
                ),
                _BigButton(
                  title: "방 찾기\n(Guest)",
                  color: Colors.green[100]!,
                  icon: Icons.search,
                  onTap: () => _showRoomListDialog(),
                ),
              ],
            ),
            const SizedBox(height: 30),
            
            ElevatedButton.icon(
              icon: const Icon(Icons.qr_code_scanner),
              label: const Text("QR 코드로 접속하기"),
              style: ElevatedButton.styleFrom(padding: const EdgeInsets.symmetric(horizontal: 30, vertical: 15)),
              onPressed: () => _openQRScanner(),
            ),
            const SizedBox(height: 10),
            TextButton(
               onPressed: () => _showManualJoinDialog(),
               child: const Text("IP 주소 직접 입력 (비상용)", style: TextStyle(color: Colors.grey)),
            ),
          ],
        ),
      ),
    );
  }

  // ------------------------------------------------------------------------
  // 2. 대기실 화면 (통합 UI)
  // ------------------------------------------------------------------------
  Widget _buildLobbyView() {
    return Column(
      children: [
        // A. 상단 정보 카드
        Container(
          width: double.infinity,
          padding: const EdgeInsets.all(20),
          decoration: BoxDecoration(
            color: Colors.grey[100],
            border: const Border(bottom: BorderSide(color: Colors.black12)),
          ),
          child: Column(
            children: [
              Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Icon(_net.role == NetworkRole.host ? Icons.wifi_tethering : Icons.wifi, color: Colors.blue),
                  const SizedBox(width: 10),
                  Text(
                    _net.role == NetworkRole.host ? "👑 방장 (나)" : "참가자 (나)",
                    style: const TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
                  ),
                ],
              ),
              
              // 방장일 경우 접속 정보 표시
              if (_net.role == NetworkRole.host) ...[
                 const SizedBox(height: 15),
                 Container(
                   padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
                   decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(20), border: Border.all(color: Colors.blue.shade100)),
                   child: Row(
                     mainAxisSize: MainAxisSize.min,
                     children: [
                       Text("IP: ${_net.hostIp}  :  ${_net.hostPort}", style: const TextStyle(fontWeight: FontWeight.bold)),
                       const SizedBox(width: 10),
                       InkWell(
                         onTap: () => _showHostQRDialog(),
                         child: const Icon(Icons.qr_code, color: Colors.black87),
                       )
                     ],
                   ),
                 ),
                 const SizedBox(height: 5),
                 const Text("QR 코드를 눌러 친구를 초대하세요!", style: TextStyle(fontSize: 12, color: Colors.grey)),
              ] else ...[
                // 참가자일 경우 방장 정보 표시
                const SizedBox(height: 10),
                Text("방장 IP: ${_net.hostIp ?? '...'}", style: const TextStyle(color: Colors.grey)),
              ]
            ],
          ),
        ),

        // B. 참가자 리스트 (나 + 게스트)
        Expanded(
          child: ListView(
            padding: const EdgeInsets.all(16),
            children: [
              const Text("대기 중인 참가자", style: TextStyle(color: Colors.grey, fontWeight: FontWeight.bold)),
              const SizedBox(height: 10),
              
              // 1. 나 (항상 맨 위)
              _buildUserTile(_net.me, isMe: true),
              
              // 2. 다른 참가자들
              ..._net.guestList.map((guest) => _buildUserTile(guest, isMe: false)),
              
              // 대기 문구
              if (_net.guestList.isEmpty && _net.role == NetworkRole.host)
                Padding(
                  padding: const EdgeInsets.only(top: 40.0),
                  child: Center(
                    child: Column(
                      children: const [
                        CircularProgressIndicator(),
                        SizedBox(height: 20),
                        Text("친구를 기다리는 중...", style: TextStyle(color: Colors.grey)),
                      ],
                    ),
                  ),
                ),
            ],
          ),
        ),

        // C. 하단 레디 버튼
        _buildReadyButton(),
      ],
    );
  }

  Widget _buildUserTile(UserInfo user, {required bool isMe}) {
    return Card(
      elevation: user.isReady ? 4 : 1,
      color: user.isReady ? Colors.green[50] : Colors.white,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(12),
        side: user.isReady ? const BorderSide(color: Colors.green, width: 2) : BorderSide.none,
      ),
      margin: const EdgeInsets.symmetric(vertical: 6),
      child: ListTile(
        contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
        leading: AvatarWidget(user: user, size: 50), // Core의 AvatarWidget 사용
        title: Text(
          user.nickname + (isMe ? " (나)" : ""),
          style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16),
        ),
        subtitle: Text(isMe ? "준비 버튼을 눌러주세요" : (user.isReady ? "준비 완료!" : "준비 중..."), style: TextStyle(color: Colors.grey[600], fontSize: 12)),
        trailing: user.isReady
            ? const Icon(Icons.check_circle, color: Colors.green, size: 32)
            : const Icon(Icons.hourglass_empty, color: Colors.grey, size: 32),
      ),
    );
  }

  Widget _buildReadyButton() {
    bool isReady = _net.me.isReady;
    // 조건: 방장이라도 게스트가 없으면 레디 불가 (혼자 게임 불가)
    // 게스트는 들어오자마자 레디 가능
    bool canReady = _net.role == NetworkRole.host ? _net.guestList.isNotEmpty : true;

    return Container(
      width: double.infinity,
      padding: const EdgeInsets.all(20),
      decoration: BoxDecoration(
        color: Colors.white,
        boxShadow: [BoxShadow(color: Colors.black12, blurRadius: 10, offset: const Offset(0, -5))],
      ),
      child: ElevatedButton(
        onPressed: canReady 
            ? () => _net.toggleReady()
            : () {
                ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text("친구를 초대해야 시작할 수 있습니다!")));
              },
        style: ElevatedButton.styleFrom(
          backgroundColor: !canReady 
              ? Colors.grey[300] 
              : (isReady ? Colors.redAccent : Colors.blueAccent),
          padding: const EdgeInsets.symmetric(vertical: 18),
          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15)),
          elevation: canReady ? 5 : 0,
        ),
        child: Text(
          isReady ? "준비 취소 (WAIT)" : "준비 완료 (READY)",
          style: TextStyle(
            fontSize: 22, 
            fontWeight: FontWeight.bold, 
            color: !canReady ? Colors.grey : Colors.white
          ),
        ),
      ),
    );
  }

  // ------------------------------------------------------------------------
  // [Components] 디버그 콘솔
  // ------------------------------------------------------------------------
  Widget _buildDebugConsole() {
    return Column(
      children: [
        GestureDetector(
          onTap: () => _scrollController.jumpTo(_scrollController.position.maxScrollExtent),
          child: Container(
            width: double.infinity,
            padding: const EdgeInsets.symmetric(vertical: 5, horizontal: 10),
            color: Colors.black87,
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: const [
                Text("DEBUG LOGS", style: TextStyle(color: Colors.white, fontWeight: FontWeight.bold, fontSize: 10)),
                Icon(Icons.keyboard_arrow_down, color: Colors.white, size: 14)
              ],
            ),
          ),
        ),
        SizedBox(
          height: 100, 
          child: Container(
            color: Colors.black,
            child: ListView.builder(
              controller: _scrollController,
              itemCount: _logs.length,
              itemBuilder: (context, index) {
                return Padding(
                  padding: const EdgeInsets.symmetric(horizontal: 8.0, vertical: 1.0),
                  child: Text(
                    _logs[index],
                    style: const TextStyle(color: Colors.greenAccent, fontSize: 10, fontFamily: 'Courier'),
                  ),
                );
              },
            ),
          ),
        ),
      ],
    );
  }

  // ------------------------------------------------------------------------
  // [Dialogs] QR, 검색, 수동입력
  // ------------------------------------------------------------------------
  void _showHostQRDialog() {
    if (_net.hostIp == null || _net.hostPort == null) return;
    final qrData = jsonEncode({'ip': _net.hostIp, 'port': _net.hostPort});
    
    showDialog(
      context: context,
      builder: (context) => Dialog(
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
        child: Padding(
          padding: const EdgeInsets.all(24.0),
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              const Text("친구 초대", style: TextStyle(fontSize: 22, fontWeight: FontWeight.bold)),
              const SizedBox(height: 20),
              Container(
                padding: const EdgeInsets.all(10),
                decoration: BoxDecoration(border: Border.all(color: Colors.black12), borderRadius: BorderRadius.circular(10)),
                child: QrImageView(data: qrData, version: QrVersions.auto, size: 220.0),
              ),
              const SizedBox(height: 20),
              SelectableText("IP: ${_net.hostIp}\nPort: ${_net.hostPort}", textAlign: TextAlign.center, style: const TextStyle(color: Colors.grey)),
              const SizedBox(height: 20),
              ElevatedButton(onPressed: () => Navigator.pop(context), child: const Text("닫기"))
            ],
          ),
        ),
      ),
    );
  }

  void _openQRScanner() {
    bool isScanCompleted = false;
    Navigator.of(context).push(MaterialPageRoute(
      builder: (context) => Scaffold(
        appBar: AppBar(title: const Text("QR 스캔")),
        body: MobileScanner(
          onDetect: (capture) {
            if (isScanCompleted) return;
            for (final barcode in capture.barcodes) {
              if (barcode.rawValue != null) {
                try {
                  final data = jsonDecode(barcode.rawValue!);
                  if (data['ip'] != null && data['port'] != null) {
                    isScanCompleted = true;
                    Navigator.pop(context);
                    ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text("접속 중...")));
                    _net.joinRoom(data['ip'], data['port']);
                    return;
                  }
                } catch (e) {}
              }
            }
          },
        ),
      ),
    ));
  }

  void _showRoomListDialog() {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text("방 찾기"),
        content: SizedBox(
          width: double.maxFinite,
          height: 300,
          child: StreamBuilder<List<BonsoirService>>(
            stream: _net.discoverRooms(),
            builder: (context, snapshot) {
              if (!snapshot.hasData || snapshot.data!.isEmpty) {
                return const Center(child: Text("검색 중...\n같은 와이파이인지 확인하세요."));
              }
              return ListView.builder(
                itemCount: snapshot.data!.length,
                itemBuilder: (context, index) {
                  final service = snapshot.data![index];
                  final ip = service.attributes?['ip'] ?? '알 수 없음';
                  return ListTile(
                    leading: const Icon(Icons.meeting_room),
                    title: Text(service.name.split('#').first),
                    subtitle: Text(ip),
                    onTap: () {
                       Navigator.pop(context);
                       if (service.attributes != null && service.attributes!['ip'] != null) {
                         _net.joinRoom(service.attributes!['ip']!, service.port);
                       }
                    },
                  );
                },
              );
            },
          ),
        ),
        actions: [TextButton(onPressed: () => Navigator.pop(context), child: const Text("닫기"))],
      ),
    );
  }

  void _showManualJoinDialog() {
    final ipCtrl = TextEditingController(text: "192.168.");
    final portCtrl = TextEditingController();
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text("직접 입력"),
        content: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            TextField(controller: ipCtrl, decoration: const InputDecoration(labelText: "IP Address")),
            TextField(controller: portCtrl, decoration: const InputDecoration(labelText: "Port")),
          ],
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: const Text("취소")),
          ElevatedButton(
            onPressed: () {
              final ip = ipCtrl.text.trim();
              final port = int.tryParse(portCtrl.text.trim());
              if (ip.isNotEmpty && port != null) {
                Navigator.pop(context);
                _net.joinRoom(ip, port);
              }
            },
            child: const Text("접속"),
          ),
        ],
      ),
    );
  }
}

class _BigButton extends StatelessWidget {
  final String title; final Color color; final IconData icon; final VoidCallback onTap;
  const _BigButton({required this.title, required this.color, required this.icon, required this.onTap});
  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: onTap,
      child: Container(
        width: 130, height: 130,
        decoration: BoxDecoration(color: color, borderRadius: BorderRadius.circular(20), boxShadow: [BoxShadow(color: Colors.black12, blurRadius: 10, offset: const Offset(0, 5))]),
        child: Column(mainAxisAlignment: MainAxisAlignment.center, children: [Icon(icon, size: 40, color: Colors.black54), const SizedBox(height: 10), Text(title, textAlign: TextAlign.center, style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold))]),
      ),
    );
  }
}