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

import 'package:arcx/app/app_theme.dart';
import 'package:arcx/features/iap/application/iap_controller.dart';

class IapUnlockDialog extends ConsumerWidget {
  const IapUnlockDialog({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final iap = ref.watch(iapControllerProvider);
    final product = iap.product;

    ref.listen(iapControllerProvider, (prev, next) {
      if (next.lastEvent != null) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text(next.lastEvent!)),
        );
        if (next.lastEvent!.contains('解锁') ||
            next.lastEvent!.contains('恢复')) {
          Navigator.of(context).pop();
        }
      } else if (next.errorMessage != null) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text(next.errorMessage!)),
        );
      }
    });

    return AlertDialog(
      title: const Text('解锁记分本'),
      content: SingleChildScrollView(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            const Text(
              '免费试用次数已用完。购买后即可永久解锁无限记分权益，无需联网即可使用。',
              style: TextStyle(fontSize: 14),
            ),
            const SizedBox(height: 16),
            _PriceRow(
              title: product?.title ?? '记分本永久解锁',
              price: iap.productsAvailable && product != null
                  ? product.price
                  : '—',
            ),
            const SizedBox(height: 8),
            _FeatureItem(text: '无限次记分训练'),
            _FeatureItem(text: '本地永久保存训练数据'),
            _FeatureItem(text: '一次购买，永久使用'),
            if (iap.isLoading) ...[
              const SizedBox(height: 12),
              const Center(child: CircularProgressIndicator()),
            ],
          ],
        ),
      ),
      actions: [
        TextButton(
          onPressed: iap.isPurchasing
              ? null
              : () => Navigator.of(context).pop(),
          child: const Text('暂不解锁'),
        ),
        TextButton(
          onPressed: iap.isPurchasing ? null : () => ref.read(iapControllerProvider.notifier).restore(),
          child: const Text('恢复购买'),
        ),
        FilledButton(
          onPressed: iap.isPurchasing || iap.isLoading
              ? null
              : () => _unlock(context, ref, iap),
          child: iap.isPurchasing
              ? const SizedBox(
                  width: 18,
                  height: 18,
                  child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white),
                )
              : const Text('立即解锁'),
        ),
      ],
    );
  }

  Future<void> _unlock(
    BuildContext context,
    WidgetRef ref,
    IapState iap,
  ) async {
    // In debug builds with no App Store product configured, fall back to a
    // dev unlock so the app remains usable for testing.
    if (kDebugMode && !iap.productsAvailable) {
      await ref.read(iapControllerProvider.notifier).debugUnlock();
      if (context.mounted) Navigator.of(context).pop();
      return;
    }
    await ref.read(iapControllerProvider.notifier).buy();
  }
}

class _PriceRow extends StatelessWidget {
  const _PriceRow({required this.title, required this.price});
  final String title;
  final String price;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
      decoration: BoxDecoration(
        color: AppTheme.surfaceMuted,
        borderRadius: BorderRadius.circular(8),
      ),
      child: Row(
        children: [
          Expanded(
            child: Text(
              title,
              style: const TextStyle(fontWeight: FontWeight.w600),
            ),
          ),
          Text(
            price,
            style: const TextStyle(
              fontSize: 18,
              fontWeight: FontWeight.w700,
              color: AppTheme.primary,
            ),
          ),
        ],
      ),
    );
  }
}

class _FeatureItem extends StatelessWidget {
  const _FeatureItem({required this.text});
  final String text;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.only(top: 8),
      child: Row(
        children: [
          const Icon(Icons.check_circle, color: AppTheme.primary, size: 18),
          const SizedBox(width: 8),
          Text(text, style: const TextStyle(fontSize: 13)),
        ],
      ),
    );
  }
}