// lib/screens/login_screen.dart

import 'dart:ui';
import '../core/utils/error_utils.dart';
import 'package:flutter/foundation.dart' show kIsWeb;
import 'package:flutter/material.dart';
import 'package:video_player/video_player.dart';
import '../features/auth/services/auth_service.dart';
import '../core/auth/auth_guard.dart';
import 'home_screen.dart';

class LoginScreen extends StatefulWidget {
  const LoginScreen({Key? key}) : super(key: key);

  @override
  State<LoginScreen> createState() => _LoginScreenState();
}

class _LoginScreenState extends State<LoginScreen> {
  final _formKey = GlobalKey<FormState>();

  final TextEditingController _emailCtrl = TextEditingController();
  final TextEditingController _passCtrl = TextEditingController();
  final FocusNode _emailFocus = FocusNode();
  final FocusNode _passFocus = FocusNode();

  final AuthService _auth = AuthService();
  bool _loading = false;
  bool _obscurePassword = true;
  bool _rememberMe = false;

  late VideoPlayerController _videoController;
  bool _videoInitialized = false;

  // Glassmorphism color palette
  static const _darkBg = Color(0xFF0A0A0A);
  static const _glassBg = Color(0x1AFFFFFF);       // 10% white
  static const _glassBorder = Color(0x33FFFFFF);    // 20% white
  static const _inputBg = Color(0x14FFFFFF);        // 8% white
  static const _inputBorder = Color(0x26FFFFFF);    // 15% white
  static const _textWhite = Colors.white;
  static const _textMuted = Color(0xFFAAAAAA);
  static const _textHint = Color(0xFF888888);

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

  Future<void> _initVideo() async {
    _videoController = VideoPlayerController.asset('assets/login-bg.mp4');
    await _videoController.initialize();
    _videoController.setLooping(true);
    _videoController.setVolume(0);
    _videoController.play();
    if (mounted) setState(() => _videoInitialized = true);
  }

  @override
  void dispose() {
    _videoController.dispose();
    _emailCtrl.dispose();
    _passCtrl.dispose();
    _emailFocus.dispose();
    _passFocus.dispose();
    super.dispose();
  }

  String? _emailValidator(String? v) {
    if (v == null || v.trim().isEmpty) return 'Enter email';
    final email = v.trim();
    final emailRegex = RegExp(r"^[^@]+@[^@]+\.[^@]+");
    if (!emailRegex.hasMatch(email)) return 'Enter a valid email';
    return null;
  }

  String? _passwordValidator(String? v) {
    if (v == null || v.trim().isEmpty) return 'Enter password';
    if (v.length < 6) return 'Password must be at least 6 characters';
    return null;
  }

  Future<void> _performLogin() async {
    final form = _formKey.currentState;
    if (form == null) return;
    if (!form.validate()) return;

    final email = _emailCtrl.text.trim();
    final password = _passCtrl.text;

    setState(() => _loading = true);

    try {
      await _auth.login(email, password);

      if (!mounted) return;
      await Future.delayed(const Duration(milliseconds: 150));

      Navigator.of(context).pushReplacement(PageRouteBuilder(
        pageBuilder: (context, a1, a2) => const HomeScreen(),
        transitionDuration: const Duration(milliseconds: 650),
        reverseTransitionDuration: const Duration(milliseconds: 350),
        transitionsBuilder: (context, animation, secondaryAnimation, child) {
          return FadeTransition(opacity: animation, child: child);
        },
      ));
    } catch (e) {
      if (!mounted) return;
      final message = userFriendlyError(e);
      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(message)));
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  void _openRegister() {
    Navigator.of(context).push(MaterialPageRoute(builder: (_) => const RegisterScreen(isDesktop: false)));
  }

  void _showComingSoon() {
    ScaffoldMessenger.of(context).showSnackBar(
      const SnackBar(content: Text('Coming soon'), duration: Duration(seconds: 1)),
    );
  }

  /// Glassmorphism pill-shaped input decoration
  InputDecoration _glassInputDecoration({
    required String hint,
    required IconData prefixIcon,
    Widget? suffixIcon,
  }) {
    const borderRadius = BorderRadius.all(Radius.circular(28));
    return InputDecoration(
      hintText: hint,
      hintStyle: const TextStyle(color: _textHint, fontSize: 14),
      prefixIcon: Padding(
        padding: const EdgeInsets.only(left: 16, right: 8),
        child: Icon(prefixIcon, color: _textMuted, size: 20),
      ),
      prefixIconConstraints: const BoxConstraints(minWidth: 44),
      suffixIcon: suffixIcon != null
          ? Padding(
              padding: const EdgeInsets.only(right: 8),
              child: suffixIcon,
            )
          : null,
      filled: true,
      fillColor: _inputBg,
      contentPadding: const EdgeInsets.symmetric(horizontal: 20, vertical: 16),
      border: OutlineInputBorder(
        borderRadius: borderRadius,
        borderSide: BorderSide(color: _inputBorder),
      ),
      enabledBorder: OutlineInputBorder(
        borderRadius: borderRadius,
        borderSide: BorderSide(color: _inputBorder),
      ),
      focusedBorder: OutlineInputBorder(
        borderRadius: borderRadius,
        borderSide: BorderSide(color: _glassBorder, width: 1.5),
      ),
      errorBorder: OutlineInputBorder(
        borderRadius: borderRadius,
        borderSide: const BorderSide(color: Colors.redAccent),
      ),
      focusedErrorBorder: OutlineInputBorder(
        borderRadius: borderRadius,
        borderSide: const BorderSide(color: Colors.redAccent, width: 1.5),
      ),
      errorStyle: const TextStyle(color: Colors.redAccent, fontSize: 11),
    );
  }

  /// Glassmorphism social button
  Widget _socialButton({
    required String label,
    required Widget icon,
    required VoidCallback onTap,
  }) {
    return Expanded(
      child: GestureDetector(
        onTap: onTap,
        child: Container(
          padding: const EdgeInsets.symmetric(vertical: 14),
          decoration: BoxDecoration(
            color: _inputBg,
            borderRadius: BorderRadius.circular(28),
            border: Border.all(color: _inputBorder),
          ),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              icon,
              const SizedBox(width: 8),
              Text(
                label,
                style: const TextStyle(
                  color: _textWhite,
                  fontSize: 13,
                  fontWeight: FontWeight.w500,
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: _darkBg,
      body: Stack(
        children: [
          // Video background
          if (_videoInitialized)
            Positioned.fill(
              child: FittedBox(
                fit: BoxFit.cover,
                child: SizedBox(
                  width: _videoController.value.size.width,
                  height: _videoController.value.size.height,
                  child: VideoPlayer(_videoController),
                ),
              ),
            ),

          // Dark gradient overlay for readability
          Positioned.fill(
            child: Container(
              decoration: BoxDecoration(
                gradient: LinearGradient(
                  begin: Alignment.topCenter,
                  end: Alignment.bottomCenter,
                  colors: [
                    Colors.black.withOpacity(0.50),
                    Colors.black.withOpacity(0.65),
                    Colors.black.withOpacity(0.70),
                  ],
                  stops: const [0.0, 0.4, 1.0],
                ),
              ),
            ),
          ),

          // Main content
          SafeArea(
            child: Center(
              child: SingleChildScrollView(
                padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 20),
                child: ConstrainedBox(
                  constraints: const BoxConstraints(maxWidth: 400),
                  child: Form(
                    key: _formKey,
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        // Brand name
                        Center(
                          child: Text(
                            'Eventify',
                            style: TextStyle(
                              color: _textWhite.withOpacity(0.7),
                              fontSize: 16,
                              fontWeight: FontWeight.w500,
                              fontStyle: FontStyle.italic,
                              letterSpacing: 1.5,
                            ),
                          ),
                        ),
                        const SizedBox(height: 12),

                        // Heading
                        const Center(
                          child: Text(
                            'Log In, Start Your\nJourney',
                            textAlign: TextAlign.center,
                            style: TextStyle(
                              color: _textWhite,
                              fontSize: 28,
                              fontWeight: FontWeight.bold,
                              fontStyle: FontStyle.italic,
                              height: 1.2,
                            ),
                          ),
                        ),
                        const SizedBox(height: 32),

                        // Email label
                        const Padding(
                          padding: EdgeInsets.only(left: 4, bottom: 8),
                          child: Text(
                            'Email',
                            style: TextStyle(color: _textMuted, fontSize: 13),
                          ),
                        ),
                        // Email input
                        TextFormField(
                          controller: _emailCtrl,
                          focusNode: _emailFocus,
                          keyboardType: TextInputType.emailAddress,
                          autofillHints: const [AutofillHints.email],
                          style: const TextStyle(color: _textWhite, fontSize: 14),
                          cursorColor: Colors.white54,
                          decoration: _glassInputDecoration(
                            hint: 'Enter your email',
                            prefixIcon: Icons.mail_outline_rounded,
                          ),
                          validator: _emailValidator,
                          textInputAction: TextInputAction.next,
                          onFieldSubmitted: (_) {
                            FocusScope.of(context).requestFocus(_passFocus);
                          },
                        ),
                        const SizedBox(height: 18),

                        // Password label
                        const Padding(
                          padding: EdgeInsets.only(left: 4, bottom: 8),
                          child: Text(
                            'Password',
                            style: TextStyle(color: _textMuted, fontSize: 13),
                          ),
                        ),
                        // Password input
                        TextFormField(
                          controller: _passCtrl,
                          focusNode: _passFocus,
                          obscureText: _obscurePassword,
                          style: const TextStyle(color: _textWhite, fontSize: 14),
                          cursorColor: Colors.white54,
                          decoration: _glassInputDecoration(
                            hint: 'Enter your password',
                            prefixIcon: Icons.lock_outline_rounded,
                            suffixIcon: IconButton(
                              icon: Icon(
                                _obscurePassword ? Icons.visibility_off_outlined : Icons.visibility_outlined,
                                color: _textMuted,
                                size: 20,
                              ),
                              onPressed: () => setState(() => _obscurePassword = !_obscurePassword),
                            ),
                          ),
                          validator: _passwordValidator,
                          textInputAction: TextInputAction.done,
                          onFieldSubmitted: (_) => _performLogin(),
                        ),
                        const SizedBox(height: 14),

                        // Remember me + Forgot Password row
                        Row(
                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
                          children: [
                            // Remember me
                            GestureDetector(
                              onTap: () => setState(() => _rememberMe = !_rememberMe),
                              child: Row(
                                mainAxisSize: MainAxisSize.min,
                                children: [
                                  Container(
                                    width: 18,
                                    height: 18,
                                    decoration: BoxDecoration(
                                      borderRadius: BorderRadius.circular(4),
                                      border: Border.all(color: _glassBorder),
                                      color: _rememberMe ? Colors.white24 : Colors.transparent,
                                    ),
                                    child: _rememberMe
                                        ? const Icon(Icons.check, size: 14, color: _textWhite)
                                        : null,
                                  ),
                                  const SizedBox(width: 8),
                                  const Text(
                                    'Remember me',
                                    style: TextStyle(color: _textMuted, fontSize: 12),
                                  ),
                                ],
                              ),
                            ),
                            // Forgot Password
                            GestureDetector(
                              onTap: _showComingSoon,
                              child: const Text(
                                'Forgot Password?',
                                style: TextStyle(color: _textMuted, fontSize: 12),
                              ),
                            ),
                          ],
                        ),
                        const SizedBox(height: 24),

                        // Login button — dark gradient pill
                        SizedBox(
                          width: double.infinity,
                          child: Container(
                            decoration: BoxDecoration(
                              borderRadius: BorderRadius.circular(28),
                              gradient: const LinearGradient(
                                colors: [Color(0xFF2A2A2A), Color(0xFF1A1A1A)],
                              ),
                              border: Border.all(color: const Color(0x33FFFFFF)),
                              boxShadow: [
                                BoxShadow(
                                  color: Colors.black.withOpacity(0.4),
                                  blurRadius: 16,
                                  offset: const Offset(0, 6),
                                ),
                              ],
                            ),
                            child: Material(
                              color: Colors.transparent,
                              child: InkWell(
                                borderRadius: BorderRadius.circular(28),
                                onTap: _loading ? null : _performLogin,
                                child: Padding(
                                  padding: const EdgeInsets.symmetric(vertical: 16),
                                  child: Center(
                                    child: _loading
                                        ? const SizedBox(
                                            height: 20,
                                            width: 20,
                                            child: CircularProgressIndicator(
                                              strokeWidth: 2,
                                              color: _textWhite,
                                            ),
                                          )
                                        : const Text(
                                            'Login',
                                            style: TextStyle(
                                              color: _textWhite,
                                              fontSize: 16,
                                              fontWeight: FontWeight.w600,
                                            ),
                                          ),
                                  ),
                                ),
                              ),
                            ),
                          ),
                        ),
                        const SizedBox(height: 24),

                        // "Or continue with" divider
                        Row(
                          children: [
                            Expanded(child: Divider(color: Colors.white.withOpacity(0.12))),
                            Padding(
                              padding: const EdgeInsets.symmetric(horizontal: 14),
                              child: Text(
                                'Or continue with',
                                style: TextStyle(
                                  color: _textMuted.withOpacity(0.7),
                                  fontSize: 12,
                                ),
                              ),
                            ),
                            Expanded(child: Divider(color: Colors.white.withOpacity(0.12))),
                          ],
                        ),
                        const SizedBox(height: 18),

                        // Social buttons — side by side
                        Row(
                          children: [
                            _socialButton(
                              label: 'Google',
                              icon: const Text(
                                'G',
                                style: TextStyle(
                                  fontSize: 18,
                                  fontWeight: FontWeight.bold,
                                  color: Color(0xFF4285F4),
                                ),
                              ),
                              onTap: _showComingSoon,
                            ),
                            const SizedBox(width: 12),
                            _socialButton(
                              label: 'Apple',
                              icon: const Icon(Icons.apple, color: _textWhite, size: 20),
                              onTap: _showComingSoon,
                            ),
                          ],
                        ),
                        const SizedBox(height: 28),

                        // Don't have an account? Create an account
                        Center(
                          child: Row(
                            mainAxisSize: MainAxisSize.min,
                            children: [
                              const Text(
                                "Don't have an account? ",
                                style: TextStyle(color: _textMuted, fontSize: 13),
                              ),
                              GestureDetector(
                                onTap: _openRegister,
                                child: const Text(
                                  'Create an account',
                                  style: TextStyle(
                                    color: _textWhite,
                                    fontSize: 13,
                                    fontWeight: FontWeight.w600,
                                    decoration: TextDecoration.underline,
                                    decorationColor: _textWhite,
                                  ),
                                ),
                              ),
                            ],
                          ),
                        ),

                        const SizedBox(height: 16),

                        // Continue as Guest
                        Center(
                          child: TextButton(
                            onPressed: () {
                              AuthGuard.setGuest(true);
                              Navigator.of(context).pushAndRemoveUntil(
                                MaterialPageRoute(builder: (_) => const HomeScreen()),
                                (route) => false,
                              );
                            },
                            style: TextButton.styleFrom(
                              padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
                            ),
                            child: const Text(
                              'Continue as Guest',
                              style: TextStyle(
                                color: Colors.white70,
                                fontSize: 15,
                                fontWeight: FontWeight.w500,
                                decoration: TextDecoration.underline,
                                decorationColor: Colors.white70,
                              ),
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}

/// Register screen calls backend register endpoint via AuthService.register
class RegisterScreen extends StatefulWidget {
  final bool isDesktop;
  const RegisterScreen({Key? key, this.isDesktop = false}) : super(key: key);

  @override
  State<RegisterScreen> createState() => _RegisterScreenState();
}

class _RegisterScreenState extends State<RegisterScreen> {
  final _formKey = GlobalKey<FormState>();
  final TextEditingController _emailCtrl = TextEditingController();
  final TextEditingController _phoneCtrl = TextEditingController();
  final TextEditingController _passCtrl = TextEditingController();
  final TextEditingController _confirmCtrl = TextEditingController();
  final AuthService _auth = AuthService();

  bool _loading = false;

  @override
  void dispose() {
    _emailCtrl.dispose();
    _phoneCtrl.dispose();
    _passCtrl.dispose();
    _confirmCtrl.dispose();
    super.dispose();
  }

  Future<void> _performRegister() async {
    if (!(_formKey.currentState?.validate() ?? false)) return;

    final email = _emailCtrl.text.trim();
    final phone = _phoneCtrl.text.trim();
    final pass = _passCtrl.text;
    final confirm = _confirmCtrl.text;

    if (pass != confirm) {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Passwords do not match')));
      return;
    }

    setState(() => _loading = true);

    try {
      await _auth.register(
        email: email,
        phoneNumber: phone,
        password: pass,
      );

      if (!mounted) return;

      Navigator.of(context).pushReplacement(MaterialPageRoute(builder: (_) => const HomeScreen()));
    } catch (e) {
      if (!mounted) return;
      final message = userFriendlyError(e);
      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(message)));
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  String? _emailValidator(String? v) {
    if (v == null || v.trim().isEmpty) return 'Enter email';
    final emailRegex = RegExp(r"^[^@]+@[^@]+\.[^@]+");
    if (!emailRegex.hasMatch(v.trim())) return 'Enter a valid email';
    return null;
  }

  String? _phoneValidator(String? v) {
    if (v == null || v.trim().isEmpty) return 'Enter phone number';
    if (v.trim().length < 7) return 'Enter a valid phone number';
    return null;
  }

  String? _passwordValidator(String? v) {
    if (v == null || v.isEmpty) return 'Enter password';
    if (v.length < 6) return 'Password must be at least 6 characters';
    return null;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Register')),
      body: SafeArea(
        child: Center(
          child: SingleChildScrollView(
            padding: const EdgeInsets.all(20),
            child: ConstrainedBox(
              constraints: const BoxConstraints(maxWidth: 520),
              child: Card(
                child: Padding(
                  padding: const EdgeInsets.all(18.0),
                  child: Form(
                    key: _formKey,
                    child: Column(
                      children: [
                        TextFormField(controller: _emailCtrl, decoration: const InputDecoration(labelText: 'Email'), validator: _emailValidator, keyboardType: TextInputType.emailAddress),
                        const SizedBox(height: 8),
                        TextFormField(controller: _phoneCtrl, decoration: const InputDecoration(labelText: 'Phone'), validator: _phoneValidator, keyboardType: TextInputType.phone),
                        const SizedBox(height: 8),
                        TextFormField(controller: _passCtrl, obscureText: true, decoration: const InputDecoration(labelText: 'Password'), validator: _passwordValidator),
                        const SizedBox(height: 8),
                        TextFormField(controller: _confirmCtrl, obscureText: true, decoration: const InputDecoration(labelText: 'Confirm password'), validator: _passwordValidator),
                        const SizedBox(height: 16),
                        SizedBox(
                          width: double.infinity,
                          child: ElevatedButton(
                            onPressed: _loading ? null : _performRegister,
                            child: _loading ? const SizedBox(width: 20, height: 20, child: CircularProgressIndicator(color: Colors.white, strokeWidth: 2)) : const Text('Register'),
                          ),
                        ),
                      ],
                    ),
                  ),
                ),
              ),
            ),
          ),
        ),
      ),
    );
  }
}
