import 'package:app/core/app/router.dart';
import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';

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

  @override
  State<LoginPage> createState() => _LoginPageState();
}

class _LoginPageState extends State<LoginPage> {
  bool _loading = false;

  Future<void> _simulateLogin() async {
    if (_loading) return;
    setState(() => _loading = true);

    // Simulate latency, perform demo login, then go home.
    await Future<void>.delayed(const Duration(milliseconds: 900));
    // await App.service<Auth>().login('demo', 'demo');

    if (!mounted) return;
    context.go(AppRoute.home.path);

    setState(() => _loading = false);
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Scaffold(
      appBar: AppBar(title: const Text('Login')),
      body: Center(
        child: ConstrainedBox(
          constraints: const BoxConstraints(maxWidth: 360),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              const FlutterLogo(size: 64),
              const SizedBox(height: 24),
              Text('Please sign in', style: theme.textTheme.titleMedium),
              const SizedBox(height: 24),
              SizedBox(
                width: double.infinity,
                child: ElevatedButton(
                  onPressed: _loading ? null : _simulateLogin,
                  child: AnimatedSwitcher(
                    duration: const Duration(milliseconds: 250),
                    transitionBuilder: (child, anim) =>
                        FadeTransition(opacity: anim, child: child),
                    child: _loading
                        ? const SizedBox(
                            key: ValueKey('loading'),
                            width: 20,
                            height: 20,
                            child: CircularProgressIndicator(strokeWidth: 2),
                          )
                        : const Text('Login', key: ValueKey('text')),
                  ),
                ),
              ),
              const SizedBox(height: 12),
              AnimatedSwitcher(
                duration: const Duration(milliseconds: 250),
                child: _loading
                    ? Padding(
                        padding: const EdgeInsets.only(top: 4),
                        child: Text(
                          'Signing you in…',
                          style: theme.textTheme.bodySmall,
                        ),
                      )
                    : const SizedBox.shrink(),
              ),
            ],
          ),
        ),
      ),
    );
  }
}