import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';

import '../../core/auth_repository.dart';
import '../../core/demo_accounts.dart';
import '../../core/session_controller.dart';
import '../../theme/toss_theme.dart';

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

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

class _LoginPageState extends ConsumerState<LoginPage> {
  final _email = TextEditingController();
  final _password = TextEditingController();
  String? _error;
  bool _busy = false;

  @override
  void dispose() {
    _email.dispose();
    _password.dispose();
    super.dispose();
  }

  void _fillDemo() {
    setState(() {
      _email.text = DemoAccounts.aliceEmail;
      _password.text = DemoAccounts.password;
      _error = null;
    });
  }

  Future<void> _submit() async {
    setState(() {
      _busy = true;
      _error = null;
    });
    try {
      final r = await ref.read(authRepositoryProvider).login(
            email: _email.text.trim(),
            password: _password.text,
          );
      await ref.read(sessionProvider.notifier).applyLogin(
            userId: r.userId,
            email: _email.text.trim(),
            defaultContextId: r.defaultContextId,
          );
      if (!mounted) return;
      context.go('/');
    } catch (e) {
      setState(() => _error = e.toString());
    } finally {
      if (mounted) setState(() => _busy = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final tt = Theme.of(context).textTheme;

    return Scaffold(
      body: SafeArea(
        child: SingleChildScrollView(
          padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 16),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              const SizedBox(height: 32),
              Center(
                child: Container(
                  width: 72,
                  height: 72,
                  decoration: BoxDecoration(
                    color: TossColors.surface,
                    borderRadius: BorderRadius.circular(22),
                    boxShadow: [
                      BoxShadow(
                        color: TossColors.blue.withValues(alpha: 0.15),
                        blurRadius: 24,
                        offset: const Offset(0, 8),
                      ),
                    ],
                  ),
                  child: const Icon(Icons.chat_bubble_rounded, size: 36, color: TossColors.blue),
                ),
              ),
              const SizedBox(height: 28),
              Text(
                'IYKYKA',
                textAlign: TextAlign.center,
                style: tt.headlineLarge?.copyWith(
                  letterSpacing: 0.5,
                  fontWeight: FontWeight.w800,
                ),
              ),
              const SizedBox(height: 6),
              Text(
                'If you know, you know.',
                textAlign: TextAlign.center,
                style: tt.bodySmall?.copyWith(color: TossColors.textSecondary),
              ),
              const SizedBox(height: 12),
              Text(
                '일상과 직장, 한 앱에서 나눠 쓰기',
                textAlign: TextAlign.center,
                style: tt.bodyMedium,
              ),
              const SizedBox(height: 40),
              Container(
                decoration: BoxDecoration(
                  color: TossColors.surface,
                  borderRadius: BorderRadius.circular(16),
                  boxShadow: [
                    BoxShadow(
                      color: Colors.black.withValues(alpha: 0.04),
                      blurRadius: 16,
                      offset: const Offset(0, 4),
                    ),
                  ],
                ),
                padding: const EdgeInsets.all(20),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text('데모로 시작하기', style: tt.titleMedium),
                    const SizedBox(height: 8),
                    Text(
                      '서버 실행 후 아래를 누르면 필드가 채워집니다. '
                      '홈에서 「데모 회사」를 고르면 직장 샘플 대화를 볼 수 있어요.',
                      style: tt.bodySmall?.copyWith(height: 1.4),
                    ),
                    const SizedBox(height: 16),
                    SizedBox(
                      width: double.infinity,
                      child: OutlinedButton(
                        onPressed: _busy ? null : _fillDemo,
                        child: const Text('데모 계정으로 채우기'),
                      ),
                    ),
                  ],
                ),
              ),
              const SizedBox(height: 28),
              TextField(
                controller: _email,
                decoration: const InputDecoration(
                  labelText: '이메일',
                  prefixIcon: Icon(Icons.mail_outline_rounded, color: TossColors.textSecondary),
                ),
                keyboardType: TextInputType.emailAddress,
                autofillHints: const [AutofillHints.email],
              ),
              const SizedBox(height: 12),
              TextField(
                controller: _password,
                decoration: const InputDecoration(
                  labelText: '비밀번호',
                  prefixIcon: Icon(Icons.lock_outline_rounded, color: TossColors.textSecondary),
                ),
                obscureText: true,
                autofillHints: const [AutofillHints.password],
              ),
              if (_error != null) ...[
                const SizedBox(height: 12),
                Text(
                  _error!,
                  style: TextStyle(color: Theme.of(context).colorScheme.error, fontSize: 13),
                ),
              ],
              const SizedBox(height: 28),
              SizedBox(
                width: double.infinity,
                height: 54,
                child: FilledButton(
                  onPressed: _busy ? null : _submit,
                  child: _busy
                      ? const SizedBox(
                          height: 22,
                          width: 22,
                          child: CircularProgressIndicator(
                            strokeWidth: 2,
                            color: Colors.white,
                          ),
                        )
                      : const Text('로그인'),
                ),
              ),
              const SizedBox(height: 8),
              TextButton(
                onPressed: _busy ? null : () => context.go('/register'),
                child: const Text('계정이 없어요'),
              ),
            ],
          ),
        ),
      ),
    );
  }
}