import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_inappwebview/flutter_inappwebview.dart';
import 'package:shared_preferences/shared_preferences.dart';

import '/audio/audio_manager.dart';

const String privacyKey = 'privacy_accepted_v1';

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

  @override
  State<StartScreen> createState() => _StartScreenState();
}

class _StartScreenState extends State<StartScreen>
    with SingleTickerProviderStateMixin {
  bool privacyAccepted = false;
  bool _isAcceptingPrivacy = false;
  bool _isNavigatingToGame = false;

  late final AnimationController _scaleController;
  late final Animation<double> _scaleAnimation;

  @override
  void initState() {
    super.initState();
    _initPrivacyState();
    _playBgm();

    _scaleController = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 900),
    );

    _scaleAnimation = Tween<double>(begin: 1.0, end: 1.08).animate(
      CurvedAnimation(parent: _scaleController, curve: Curves.easeInOut),
    );

    _scaleController.repeat(reverse: true);
  }

  Future<void> _initPrivacyState() async {
    try {
      final prefs = await SharedPreferences.getInstance();
      final value = prefs.getString(privacyKey);
      if (!mounted) return;
      setState(() {
        privacyAccepted = value == '1';
      });
    } catch (_) {}
  }

  Future<void> _persistPrivacyAccepted() async {
    try {
      final prefs = await SharedPreferences.getInstance();
      await prefs.setString(privacyKey, '1');
    } catch (_) {}
  }

  Future<void> _playBgm() async {
    try {
      AudioManager.instance.playBgm();
      debugPrint('BGM started');
    } catch (e) {
      debugPrint('Failed to play BGM: $e');
    }
  }

  void _goGame() {
    if (_isNavigatingToGame || !mounted) return;
    _isNavigatingToGame = true;
    Navigator.of(context).pushReplacementNamed('/game');
  }

  void onStart() {
    unawaited(_handleStart());
  }

  Future<void> _handleStart() async {
    if (_isNavigatingToGame || _isAcceptingPrivacy) return;

    if (privacyAccepted) {
      _goGame();
      return;
    }

    final agreed = await _showPrivacyConfirmDialog();
    if (!mounted || agreed != true) return;

    await _acceptPrivacyAndStart();
  }

  Future<void> _acceptPrivacyAndStart() async {
    if (_isAcceptingPrivacy || _isNavigatingToGame) return;

    setState(() {
      _isAcceptingPrivacy = true;
      privacyAccepted = true;
    });

    unawaited(_persistPrivacyAccepted());
    await Future<void>.delayed(const Duration(milliseconds: 220));
    if (!mounted) return;
    _goGame();
  }

  Future<bool?> _showPrivacyConfirmDialog() {
    return showDialog<bool>(
      context: context,
      barrierDismissible: false,
      builder: (dialogContext) {
        return Dialog(
          insetPadding: const EdgeInsets.symmetric(horizontal: 20),
          backgroundColor: Colors.transparent,
          child: Container(
            width: double.infinity,
            constraints: const BoxConstraints(maxWidth: 420),
            padding: const EdgeInsets.all(16),
            decoration: BoxDecoration(
              color: const Color.fromRGBO(20, 24, 60, 0.96),
              borderRadius: BorderRadius.circular(18),
              border: Border.all(
                color: const Color.fromRGBO(120, 255, 255, 0.25),
                width: 2,
              ),
              boxShadow: const [
                BoxShadow(
                  color: Color.fromRGBO(0, 0, 0, 0.35),
                  blurRadius: 18,
                  offset: Offset(0, 8),
                ),
              ],
            ),
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                const Text(
                  'Privacy Notice',
                  textAlign: TextAlign.center,
                  style: TextStyle(
                    fontSize: 18,
                    fontWeight: FontWeight.w900,
                    color: Colors.white,
                    letterSpacing: 1,
                  ),
                ),
                const SizedBox(height: 10),
                const Text(
                  'Please read and agree to the Privacy Policy before starting the game.',
                  textAlign: TextAlign.center,
                  style: TextStyle(
                    fontSize: 14,
                    height: 1.45,
                    color: Color.fromRGBO(255, 255, 255, 0.9),
                  ),
                ),
                const SizedBox(height: 10),
                GestureDetector(
                  onTap: () async {
                    final agreed = await _showPrivacyDialog();
                    if (!dialogContext.mounted || agreed != true) return;
                    Navigator.of(dialogContext).pop(true);
                  },
                  child: const Padding(
                    padding: EdgeInsets.symmetric(vertical: 8, horizontal: 10),
                    child: Text(
                      'View Privacy Policy',
                      style: TextStyle(
                        color: Color(0xFF56F0FF),
                        fontSize: 14,
                        fontWeight: FontWeight.w800,
                        decoration: TextDecoration.underline,
                      ),
                    ),
                  ),
                ),
                const SizedBox(height: 12),
                Row(
                  children: [
                    Expanded(
                      child: SizedBox(
                        height: 46,
                        child: OutlinedButton(
                          onPressed: () =>
                              Navigator.of(dialogContext).pop(false),
                          style: OutlinedButton.styleFrom(
                            backgroundColor: const Color.fromRGBO(
                              255,
                              255,
                              255,
                              0.08,
                            ),
                            side: const BorderSide(
                              color: Color.fromRGBO(255, 255, 255, 0.18),
                              width: 2,
                            ),
                            shape: RoundedRectangleBorder(
                              borderRadius: BorderRadius.circular(14),
                            ),
                          ),
                          child: const Text(
                            'Cancel',
                            style: TextStyle(
                              color: Colors.white,
                              fontSize: 14,
                              fontWeight: FontWeight.w900,
                              letterSpacing: 0.5,
                            ),
                          ),
                        ),
                      ),
                    ),
                    const SizedBox(width: 12),
                    Expanded(
                      child: SizedBox(
                        height: 46,
                        child: OutlinedButton(
                          onPressed: () =>
                              Navigator.of(dialogContext).pop(true),
                          style: OutlinedButton.styleFrom(
                            backgroundColor: const Color.fromRGBO(
                              50,
                              160,
                              255,
                              0.9,
                            ),
                            side: const BorderSide(
                              color: Color.fromRGBO(255, 255, 255, 0.22),
                              width: 2,
                            ),
                            shape: RoundedRectangleBorder(
                              borderRadius: BorderRadius.circular(14),
                            ),
                          ),
                          child: const Text(
                            'Agree & Start',
                            style: TextStyle(
                              color: Colors.white,
                              fontSize: 14,
                              fontWeight: FontWeight.w900,
                              letterSpacing: 0.5,
                            ),
                          ),
                        ),
                      ),
                    ),
                  ],
                ),
              ],
            ),
          ),
        );
      },
    );
  }

  Future<bool?> _showPrivacyDialog() {
    return showDialog<bool>(
      context: context,
      barrierDismissible: false,
      builder: (dialogContext) {
        return Dialog(
          insetPadding: const EdgeInsets.symmetric(
            horizontal: 16,
            vertical: 24,
          ),
          backgroundColor: Colors.transparent,
          child: ClipRRect(
            borderRadius: BorderRadius.circular(12),
            child: Container(
              color: Colors.white,
              width: double.infinity,
              height: MediaQuery.of(dialogContext).size.height * 0.82,
              child: Column(
                children: [
                  Container(
                    height: 48,
                    padding: const EdgeInsets.symmetric(horizontal: 12),
                    decoration: const BoxDecoration(
                      color: Colors.white,
                      border: Border(
                        bottom: BorderSide(
                          color: Color(0xFFDDDDDD),
                          width: 0.5,
                        ),
                      ),
                    ),
                    child: Row(
                      children: [
                        const Expanded(
                          child: Text(
                            'Privacy Policy',
                            style: TextStyle(
                              fontSize: 16,
                              fontWeight: FontWeight.w600,
                              color: Colors.black,
                            ),
                          ),
                        ),
                        GestureDetector(
                          onTap: () => Navigator.of(dialogContext).pop(false),
                          child: const Padding(
                            padding: EdgeInsets.symmetric(
                              vertical: 6,
                              horizontal: 10,
                            ),
                            child: Text(
                              'Close',
                              style: TextStyle(
                                fontSize: 14,
                                color: Color(0xFF007AFF),
                              ),
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                  const Expanded(child: _PrivacyInAppWebView()),
                  Container(
                    padding: const EdgeInsets.fromLTRB(16, 12, 16, 16),
                    decoration: const BoxDecoration(
                      color: Colors.white,
                      border: Border(
                        top: BorderSide(color: Color(0xFFDDDDDD), width: 0.5),
                      ),
                    ),
                    child: Row(
                      children: [
                        Expanded(
                          child: SizedBox(
                            height: 46,
                            child: OutlinedButton(
                              onPressed: () =>
                                  Navigator.of(dialogContext).pop(false),
                              style: OutlinedButton.styleFrom(
                                side: const BorderSide(
                                  color: Color(0xFFBFC6D4),
                                  width: 1.2,
                                ),
                                shape: RoundedRectangleBorder(
                                  borderRadius: BorderRadius.circular(12),
                                ),
                              ),
                              child: const Text(
                                'Close',
                                style: TextStyle(
                                  color: Color(0xFF3B4657),
                                  fontSize: 15,
                                  fontWeight: FontWeight.w700,
                                ),
                              ),
                            ),
                          ),
                        ),
                        const SizedBox(width: 12),
                        Expanded(
                          child: SizedBox(
                            height: 46,
                            child: FilledButton(
                              onPressed: () =>
                                  Navigator.of(dialogContext).pop(true),
                              style: FilledButton.styleFrom(
                                backgroundColor: const Color(0xFF2E8BFF),
                                shape: RoundedRectangleBorder(
                                  borderRadius: BorderRadius.circular(12),
                                ),
                              ),
                              child: const Text(
                                'Agree',
                                style: TextStyle(
                                  fontSize: 15,
                                  fontWeight: FontWeight.w800,
                                ),
                              ),
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                ],
              ),
            ),
          ),
        );
      },
    );
  }

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

  Widget _buildBackground() {
    return Positioned.fill(
      child: DecoratedBox(
        decoration: const BoxDecoration(color: Colors.black),
        child: Image.asset(
          'assets/images/bg/freecell_bg3.png',
          fit: BoxFit.cover,
          alignment: Alignment.center,
        ),
      ),
    );
  }

  Widget _buildMainContent() {
    return SafeArea(
      child: SizedBox.expand(
        child: Column(
          children: [
            const Spacer(),
            Padding(
              padding: const EdgeInsets.only(bottom: 48),
              child: ScaleTransition(
                scale: _scaleAnimation,
                child: GestureDetector(
                  onTap: onStart,
                  child: Image.asset(
                    'assets/images/bg/start.png',
                    width: 260,
                    height: 90,
                    fit: BoxFit.contain,
                  ),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.black,
      body: SizedBox.expand(
        child: Stack(
          fit: StackFit.expand,
          children: [_buildBackground(), _buildMainContent()],
        ),
      ),
    );
  }
}

class _PrivacyInAppWebView extends StatefulWidget {
  const _PrivacyInAppWebView();

  @override
  State<_PrivacyInAppWebView> createState() => _PrivacyInAppWebViewState();
}

class _PrivacyInAppWebViewState extends State<_PrivacyInAppWebView> {
  bool _isLoaded = false;

  @override
  Widget build(BuildContext context) {
    return DecoratedBox(
      decoration: const BoxDecoration(color: Colors.white),
      child: Stack(
        fit: StackFit.expand,
        children: [
          AnimatedOpacity(
            opacity: _isLoaded ? 1 : 0,
            duration: const Duration(milliseconds: 180),
            child: InAppWebView(
              initialSettings: InAppWebViewSettings(
                javaScriptEnabled: true,
                transparentBackground: false,
                supportZoom: true,
                useShouldOverrideUrlLoading: true,
              ),
              onWebViewCreated: (controller) async {
                await controller.loadFile(
                  assetFilePath: 'assets/html/privacy.html',
                );
              },
              shouldOverrideUrlLoading: (controller, navigationAction) async {
                return NavigationActionPolicy.ALLOW;
              },
              onLoadStop: (controller, url) async {
                if (!mounted) return;
                setState(() {
                  _isLoaded = true;
                });
                debugPrint('Privacy page loaded: $url');
              },
              onReceivedError: (controller, request, error) {
                if (!mounted) return;
                setState(() {
                  _isLoaded = true;
                });
                debugPrint('Privacy page load error: ${error.description}');
              },
              onConsoleMessage: (controller, consoleMessage) {
                debugPrint('WebView console: ${consoleMessage.message}');
              },
            ),
          ),
          if (!_isLoaded)
            const ColoredBox(
              color: Colors.white,
              child: Center(
                child: SizedBox(
                  width: 26,
                  height: 26,
                  child: CircularProgressIndicator(strokeWidth: 2.6),
                ),
              ),
            ),
        ],
      ),
    );
  }
}