import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import '../../core/app_colors.dart';
import '../../di/service_locator.dart';
import '../../domain/usecase/apply_promo_code_usecase.dart';
import '../components/custom_app_bar.dart';
import '../event/promo_code_event.dart';
import '../state/promo_code_state.dart';
import '../viewmodel/promo_code_bloc.dart';

class PromoCodeScreen extends StatelessWidget {
  const PromoCodeScreen({super.key});

  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (context) => PromoCodeBloc(getIt<ApplyPromoCodeUsecase>()),
      child: const _PromoCodeScreenContent(),
    );
  }
}

class _PromoCodeScreenContent extends StatefulWidget {
  const _PromoCodeScreenContent();

  @override
  State<_PromoCodeScreenContent> createState() => _PromoCodeScreenContentState();
}

class _PromoCodeScreenContentState extends State<_PromoCodeScreenContent> {
  final TextEditingController promoController = TextEditingController();

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      resizeToAvoidBottomInset: false,
      body: Container(
        decoration: const BoxDecoration(gradient: AppColors.phoneScreenBg),
        child: SafeArea(
          child: Column(
            children: [
              Expanded(
                child: Padding(
                  padding: const EdgeInsets.symmetric(horizontal: 20),
                  child: Column(
                    children: [
                      const SizedBox(height: 16),
                      CustomAppBar(title: 'Промокоды'),
                      const SizedBox(height: 32),

                      // 🔹 LISTENER: Только сайд-эффекты (SnackBar, навигация)
                      BlocListener<PromoCodeBloc, PromoCodeState>(
                        listener: (context, state) {
                          if (state.status == PromoCodeStatus.success) {
                            ScaffoldMessenger.of(context).showSnackBar(
                              SnackBar(
                                content: Text(
                                  'Промокод активирован! Баланс: ${state.newBalance?.toStringAsFixed(2)} BYN',
                                ),
                                backgroundColor: Colors.green,
                              ),
                            );
                            // Очищаем поле визуально
                            promoController.clear();
                            // Ждем чуть меньше, чтобы пользователь увидел успех
                            Future.delayed(const Duration(milliseconds: 1200), () {
                              if (mounted) Navigator.pop(context);
                            });
                          } else if (state.status == PromoCodeStatus.failure) {
                            ScaffoldMessenger.of(context).showSnackBar(
                              SnackBar(
                                content: Text(state.errorMessage ?? 'Ошибка активации'),
                                backgroundColor: Colors.red,
                              ),
                            );
                          }
                        },
                        child: BlocBuilder<PromoCodeBloc, PromoCodeState>(
                          builder: (context, state) {
                            final bool hasError = state.status == PromoCodeStatus.failure;
                            final bool isLoading = state.status == PromoCodeStatus.loading;

                            return Container(
                              padding: const EdgeInsets.all(25),
                              decoration: BoxDecoration(
                                color: const Color(0xFF141530),
                                borderRadius: BorderRadius.circular(16),
                              ),
                              child: Column(
                                crossAxisAlignment: CrossAxisAlignment.start,
                                children: [
                                  const Text(
                                    'У вас есть промокод?',
                                    style: TextStyle(color: Colors.white, fontSize: 18, fontWeight: FontWeight.w600),
                                  ),
                                  const SizedBox(height: 24),
                                  const Text(
                                    'Введите промокод и получите скидку на поездку',
                                    style: TextStyle(color: AppColors.white70, fontSize: 16),
                                  ),
                                  const SizedBox(height: 20),

                                  TextField(
                                    controller: promoController,
                                    enabled: !isLoading,
                                    style: TextStyle(color: hasError ? Colors.red : Colors.white),
                                    decoration: InputDecoration(
                                      hintText: 'Введите промокод',
                                      hintStyle: const TextStyle(color: AppColors.white70),
                                      filled: true,
                                      fillColor: Colors.white.withOpacity(0.1),
                                      border: OutlineInputBorder(
                                        borderRadius: BorderRadius.circular(24),
                                        borderSide: BorderSide.none,
                                      ),
                                      enabledBorder: OutlineInputBorder(
                                        borderRadius: BorderRadius.circular(24),
                                        borderSide: BorderSide.none,
                                      ),
                                      focusedBorder: OutlineInputBorder(
                                        borderRadius: BorderRadius.circular(24),
                                        borderSide: BorderSide(
                                          color: hasError ? Colors.red : AppColors.smsDigit,
                                          width: 1.5,
                                        ),
                                      ),
                                      // ✅ Явно убираем ошибку при успехе
                                      errorText: hasError ? 'Неверный промокод' : null,
                                    ),
                                    onSubmitted: (_) => _submit(context),
                                  ),
                                  const SizedBox(height: 20),

                                  Row(
                                    children: [
                                      Expanded(
                                        child: OutlinedButton(
                                          onPressed: isLoading ? null : () => Navigator.pop(context),
                                          style: OutlinedButton.styleFrom(
                                            shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(24)),
                                            side: BorderSide(color: AppColors.white70.withOpacity(0.4)),
                                            padding: const EdgeInsets.symmetric(vertical: 12),
                                          ),
                                          child: const Text('Отмена', style: TextStyle(color: AppColors.white70)),
                                        ),
                                      ),
                                      const SizedBox(width: 22),
                                      Expanded(
                                        child: ElevatedButton(
                                          onPressed: isLoading ? null : () => _submit(context),
                                          style: ElevatedButton.styleFrom(
                                            shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(24)),
                                            backgroundColor: AppColors.activeButtonGradient.colors[0],
                                            padding: const EdgeInsets.symmetric(vertical: 12),
                                          ),
                                          child: isLoading
                                              ? const SizedBox(
                                            width: 20,
                                            height: 20,
                                            child: CircularProgressIndicator(color: AppColors.activeButtonText, strokeWidth: 2),
                                          )
                                              : const Text('Активировать', style: TextStyle(color: AppColors.activeButtonText)),
                                        ),
                                      ),
                                    ],
                                  ),
                                ],
                              ),
                            );
                          },
                        ),
                      ),
                      const Spacer(),
                    ],
                  ),
                ),
              ),
              Image.asset(
                'assets/promo_bottom.png',
                width: double.infinity,
                fit: BoxFit.contain,
                alignment: Alignment.center,
              ),
              const SizedBox(height: 80),
            ],
          ),
        ),
      ),
    );
  }

  void _submit(BuildContext context) {
    final code = promoController.text.trim();
    if (code.isEmpty) return;
    context.read<PromoCodeBloc>().add(PromoCodeApplyRequested(code));
  }
}