import 'package:flutter/material.dart';
import 'package:google_fonts/google_fonts.dart';
import 'dart:async';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:inventory_system/services/auth_service.dart';
import 'package:inventory_system/services/session_manager.dart';
import 'package:inventory_system/screens/admin/home_screen/home_screen.dart';
import 'package:inventory_system/screens/user/home_screen/home_screen_user.dart';

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

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

class _SplashScreenState extends State<SplashScreen> with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _fadeAnimation;
  late Animation<double> _scaleAnimation;
  late Animation<Offset> _slideAnimation;

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

    _controller = AnimationController(
      duration: const Duration(milliseconds: 2000),
      vsync: this,
    );

    _fadeAnimation = Tween<double>(begin: 0.0, end: 1.0).animate(
      CurvedAnimation(
          parent: _controller,
          curve: const Interval(0.0, 0.6, curve: Curves.easeOut)),
    );

    _scaleAnimation = Tween<double>(begin: 0.5, end: 1.0).animate(
      CurvedAnimation(
          parent: _controller,
          curve: const Interval(0.0, 0.8, curve: Curves.elasticOut)),
    );

    _slideAnimation =
        Tween<Offset>(begin: const Offset(0, 0.5), end: Offset.zero).animate(
          CurvedAnimation(
              parent: _controller,
              curve: const Interval(0.3, 1.0, curve: Curves.easeOutBack)),
        );

    _controller.forward();

    _checkSession();
  }

  Future<void> _checkSession() async {
    // Wait for the animation to be mostly done so the splash isn't skipped too fast
    await Future.delayed(const Duration(seconds: 3));

    final prefs = await SharedPreferences.getInstance();
    final rememberMe = prefs.getBool('remember_me') ?? false;
    final email = prefs.getString('saved_email');
    final password = prefs.getString('saved_password');

    if (rememberMe && email != null && password != null && email.isNotEmpty && password.isNotEmpty) {
      // Attempt silent login
      try {
        final authService = AuthService();
        final result = await authService.signIn(usernameOrEmail: email, password: password);

        if (!mounted) return;

        if (result['success'] == true) {
          SessionManager.instance.startSession(result['data']);
          final bool isAdmin = result['data']?['isAdmin'] ?? false;
          
          Navigator.pushReplacement(
            context,
            MaterialPageRoute(
              builder: (context) => isAdmin ? const HomeScreen() : const UserHomeScreen(),
            ),
          );
          return;
        }
      } catch (e) {
        // Login failed, proceed to login screen
      }
    }

    if (!mounted) return;
    Navigator.pushReplacementNamed(context, '/login');
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        decoration: const BoxDecoration(
          gradient: LinearGradient(
            begin: Alignment.topLeft,
            end: Alignment.bottomRight,
            colors: [
              Color(0xFF0D47A1),
              Color(0xFF1976D2),
              Color(0xFF42A5F5),
              Color(0xFF90CAF9),
            ],
            stops: [0.0, 0.3, 0.7, 1.0],
          ),
        ),
        child: SafeArea(
          child: Center(
            child: FadeTransition(
              opacity: _fadeAnimation,
              child: Column(
                mainAxisSize: MainAxisSize.min,
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  ScaleTransition(
                    scale: _scaleAnimation,
                    child: Image.asset(
                      'assets/images/logo.png',
                      width: 380,
                      height: 380,
                      fit: BoxFit.contain,
                      gaplessPlayback: true,
                    ),
                  ),
                  Transform.translate(
                    offset: const Offset(0, -140),
                    child: SlideTransition(
                      position: _slideAnimation,
                      child: Text(
                        'INVENTORY\nSYSTEM',
                        textAlign: TextAlign.center,
                        style: GoogleFonts.roboto(
                          fontSize: 36,
                          fontWeight: FontWeight.w900,
                          letterSpacing: 4,
                          color: Colors.white,
                          height: 1.0,
                          shadows: [
                            Shadow(
                              offset: const Offset(2, 2),
                              blurRadius: 6,
                              color: Colors.black.withOpacity(0.4),
                            ),
                          ],
                        ),
                      ),
                    ),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }
}