import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:sizer/sizer.dart';

import '../../../core/app_export.dart';

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

  @override
  State<SplashScreen> createState() => _SplashScreenState();
}

class _SplashScreenState extends State<SplashScreen>
    with TickerProviderStateMixin {
  late AnimationController _logoAnimationController;
  late AnimationController _loadingAnimationController;
  late Animation<double> _logoFadeAnimation;
  late Animation<double> _logoScaleAnimation;
  late Animation<double> _loadingOpacityAnimation;

  bool _showLoading = false;
  bool _initializationComplete = false;
  String _statusMessage = 'Iniciando SIBU...';

  @override
  void initState() {
    super.initState();
    _setupAnimations();
    _startInitialization();
  }

  void _setupAnimations() {
    // Logo animation controller
    _logoAnimationController = AnimationController(
      duration: const Duration(milliseconds: 1500),
      vsync: this,
    );

    // Loading animation controller
    _loadingAnimationController = AnimationController(
      duration: const Duration(milliseconds: 800),
      vsync: this,
    );

    // Logo fade in animation
    _logoFadeAnimation = Tween<double>(
      begin: 0.0,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _logoAnimationController,
      curve: const Interval(0.0, 0.6, curve: Curves.easeOut),
    ));

    // Logo scale animation
    _logoScaleAnimation = Tween<double>(
      begin: 0.8,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _logoAnimationController,
      curve: const Interval(0.0, 0.8, curve: Curves.elasticOut),
    ));

    // Loading indicator opacity animation
    _loadingOpacityAnimation = Tween<double>(
      begin: 0.0,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _loadingAnimationController,
      curve: Curves.easeIn,
    ));

    // Start logo animation
    _logoAnimationController.forward();
  }

  Future<void> _startInitialization() async {
    try {
      // Show loading indicator after logo animation
      await Future.delayed(const Duration(milliseconds: 1000));
      setState(() {
        _showLoading = true;
      });
      _loadingAnimationController.forward();

      // Simulate initialization tasks
      await _performInitializationTasks();

      // Mark initialization as complete
      setState(() {
        _initializationComplete = true;
        _statusMessage = 'Listo para usar';
      });

      // Navigate to main screen after brief delay
      await Future.delayed(const Duration(milliseconds: 500));
      _navigateToMainScreen();
    } catch (e) {
      _handleInitializationError(e);
    }
  }

  Future<void> _performInitializationTasks() async {
    // Task 1: Check GPS permissions
    setState(() {
      _statusMessage = 'Verificando permisos GPS...';
    });
    await Future.delayed(const Duration(milliseconds: 600));

    // Task 2: Load cached route data
    setState(() {
      _statusMessage = 'Cargando datos de rutas...';
    });
    await Future.delayed(const Duration(milliseconds: 700));

    // Task 3: Fetch latest bus schedules
    setState(() {
      _statusMessage = 'Actualizando horarios...';
    });
    await Future.delayed(const Duration(milliseconds: 800));

    // Task 4: Prepare map tiles
    setState(() {
      _statusMessage = 'Preparando mapas...';
    });
    await Future.delayed(const Duration(milliseconds: 500));
  }

  void _navigateToMainScreen() {
    // Navigate to map screen (main tab)
    Navigator.pushReplacementNamed(context, '/map-screen');
  }

  void _handleInitializationError(dynamic error) {
    setState(() {
      _statusMessage = 'Error de conexión';
    });

    // Show continue offline option after 5 seconds
    Future.delayed(const Duration(seconds: 5), () {
      if (mounted && !_initializationComplete) {
        _showContinueOfflineDialog();
      }
    });
  }

  void _showContinueOfflineDialog() {
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (BuildContext context) {
        return AlertDialog(
          backgroundColor: AppTheme.lightTheme.colorScheme.surface,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(16),
          ),
          title: Text(
            'Continuar sin conexión',
            style: AppTheme.lightTheme.textTheme.titleLarge?.copyWith(
              color: AppTheme.lightTheme.colorScheme.onSurface,
            ),
          ),
          content: Text(
            'No se pudo conectar al servidor. ¿Deseas continuar con datos guardados?',
            style: AppTheme.lightTheme.textTheme.bodyMedium?.copyWith(
              color: AppTheme.lightTheme.colorScheme.onSurface,
            ),
          ),
          actions: [
            TextButton(
              onPressed: () {
                Navigator.of(context).pop();
                _startInitialization(); // Retry
              },
              child: Text(
                'Reintentar',
                style: TextStyle(
                  color: AppTheme.lightTheme.colorScheme.primary,
                ),
              ),
            ),
            ElevatedButton(
              onPressed: () {
                Navigator.of(context).pop();
                _navigateToMainScreen();
              },
              style: ElevatedButton.styleFrom(
                backgroundColor: AppTheme.accentYellow,
                foregroundColor: AppTheme.primaryBlack,
              ),
              child: const Text('Continuar'),
            ),
          ],
        );
      },
    );
  }

  Widget _buildLogo() {
    return AnimatedBuilder(
      animation: _logoAnimationController,
      builder: (context, child) {
        return Transform.scale(
          scale: _logoScaleAnimation.value,
          child: Opacity(
            opacity: _logoFadeAnimation.value,
            child: Container(
              width: 35.w,
              height: 35.w,
              decoration: BoxDecoration(
                color: AppTheme.accentYellow,
                borderRadius: BorderRadius.circular(20),
                boxShadow: [
                  BoxShadow(
                    color: AppTheme.primaryBlack.withValues(alpha: 0.2),
                    blurRadius: 20,
                    offset: const Offset(0, 8),
                  ),
                ],
              ),
              child: Center(
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    CustomIconWidget(
                      iconName: 'directions_bus',
                      color: AppTheme.primaryBlack,
                      size: 12.w,
                    ),
                    SizedBox(height: 1.h),
                    Text(
                      'SIBU',
                      style:
                          AppTheme.lightTheme.textTheme.headlineSmall?.copyWith(
                        color: AppTheme.primaryBlack,
                        fontWeight: FontWeight.bold,
                        letterSpacing: 2,
                      ),
                    ),
                  ],
                ),
              ),
            ),
          ),
        );
      },
    );
  }

  Widget _buildLoadingIndicator() {
    return _showLoading
        ? AnimatedBuilder(
            animation: _loadingAnimationController,
            builder: (context, child) {
              return Opacity(
                opacity: _loadingOpacityAnimation.value,
                child: Column(
                  children: [
                    SizedBox(height: 8.h),
                    SizedBox(
                      width: 8.w,
                      height: 8.w,
                      child: CircularProgressIndicator(
                        strokeWidth: 3,
                        valueColor: AlwaysStoppedAnimation<Color>(
                          AppTheme.accentYellow,
                        ),
                        backgroundColor:
                            AppTheme.accentYellow.withValues(alpha: 0.3),
                      ),
                    ),
                    SizedBox(height: 3.h),
                    Text(
                      _statusMessage,
                      style: AppTheme.lightTheme.textTheme.bodyMedium?.copyWith(
                        color: AppTheme.surfaceWhite.withValues(alpha: 0.8),
                      ),
                      textAlign: TextAlign.center,
                    ),
                  ],
                ),
              );
            },
          )
        : const SizedBox.shrink();
  }

  Widget _buildVersionInfo() {
    return Positioned(
      bottom: 8.h,
      left: 0,
      right: 0,
      child: Column(
        children: [
          Text(
            'Transporte Público Boquete',
            style: AppTheme.lightTheme.textTheme.bodySmall?.copyWith(
              color: AppTheme.surfaceWhite.withValues(alpha: 0.6),
            ),
          ),
          SizedBox(height: 1.h),
          Text(
            'Versión 1.0.0',
            style: AppTheme.lightTheme.textTheme.labelSmall?.copyWith(
              color: AppTheme.surfaceWhite.withValues(alpha: 0.4),
            ),
          ),
        ],
      ),
    );
  }

  @override
  void dispose() {
    _logoAnimationController.dispose();
    _loadingAnimationController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AnnotatedRegion<SystemUiOverlayStyle>(
      value: SystemUiOverlayStyle(
        statusBarColor: Colors.transparent,
        statusBarIconBrightness: Brightness.light,
        statusBarBrightness: Brightness.dark,
        systemNavigationBarColor: AppTheme.primaryBlack,
        systemNavigationBarIconBrightness: Brightness.light,
      ),
      child: Scaffold(
        backgroundColor: AppTheme.primaryBlack,
        body: SafeArea(
          child: SizedBox(
            width: double.infinity,
            height: double.infinity,
            child: Stack(
              children: [
                // Main content
                Center(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: [
                      _buildLogo(),
                      _buildLoadingIndicator(),
                    ],
                  ),
                ),
                // Version info
                _buildVersionInfo(),
              ],
            ),
          ),
        ),
      ),
    );
  }
}