ai_english/client/lib/shared/widgets/error_handler.dart

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../providers/error_provider.dart';

/// 全局错误处理组件
class GlobalErrorHandler extends ConsumerWidget {
  final Widget child;

  const GlobalErrorHandler({super.key, required this.child});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final errorState = ref.watch(errorProvider);
    
    // 监听错误状态变化
    ref.listen<ErrorState>(errorProvider, (previous, next) {
      if (next.currentError != null) {
        _showErrorDialog(context, next.currentError!, ref);
      }
    });

    return child;
  }

  void _showErrorDialog(BuildContext context, AppError error, WidgetRef ref) {
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (context) => ErrorDialog(
        error: error,
        onDismiss: () {
          Navigator.of(context).pop();
          ref.read(errorProvider.notifier).removeError(error.id);
        },
        onRetry: null,
      ),
    );
  }
}

/// 错误对话框
class ErrorDialog extends StatelessWidget {
  final AppError error;
  final VoidCallback onDismiss;
  final VoidCallback? onRetry;

  const ErrorDialog({
    super.key,
    required this.error,
    required this.onDismiss,
    this.onRetry,
  });

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: Row(
        children: [
          Icon(
            _getErrorIcon(),
            color: _getErrorColor(),
          ),
          const SizedBox(width: 8),
          Text(_getErrorTitle()),
        ],
      ),
      content: Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(error.message),
          if (error.details != null) ...[
            const SizedBox(height: 8),
            Text(
              error.details!,
              style: Theme.of(context).textTheme.bodySmall,
            ),
          ],
        ],
      ),
      actions: [
        if (onRetry != null)
          TextButton(
            onPressed: () {
              onDismiss();
              onRetry!();
            },
            child: const Text('重试'),
          ),
        TextButton(
          onPressed: onDismiss,
          child: const Text('确定'),
        ),
      ],
    );
  }

  IconData _getErrorIcon() {
    switch (error.type) {
      case ErrorType.network:
        return Icons.wifi_off;
      case ErrorType.authentication:
        return Icons.lock;
      case ErrorType.validation:
        return Icons.warning;
      case ErrorType.server:
        return Icons.error;
      case ErrorType.unknown:
      default:
        return Icons.help_outline;
    }
  }

  Color _getErrorColor() {
    switch (error.severity) {
      case ErrorSeverity.critical:
        return Colors.red;
      case ErrorSeverity.error:
        return Colors.orange;
      case ErrorSeverity.warning:
        return Colors.yellow[700]!;
      case ErrorSeverity.info:
        return Colors.blue;
    }
  }

  String _getErrorTitle() {
    switch (error.type) {
      case ErrorType.network:
        return '网络错误';
      case ErrorType.authentication:
        return '认证错误';
      case ErrorType.validation:
        return '验证错误';
      case ErrorType.server:
        return '服务器错误';
      case ErrorType.unknown:
      default:
        return '未知错误';
    }
  }
}

/// 错误横幅组件
class ErrorBanner extends ConsumerWidget {
  const ErrorBanner({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final errorState = ref.watch(errorProvider);
    
    if (!errorState.hasErrors) {
      return const SizedBox.shrink();
    }

    final lowSeverityErrors = errorState.errors
        .where((error) => error.severity == ErrorSeverity.info)
        .toList();

    if (lowSeverityErrors.isEmpty) {
      return const SizedBox.shrink();
    }

    return Container(
      width: double.infinity,
      padding: const EdgeInsets.all(12),
      color: Colors.blue[50],
      child: Row(
        children: [
          Icon(
            Icons.info_outline,
            color: Colors.blue[700],
            size: 20,
          ),
          const SizedBox(width: 8),
          Expanded(
            child: Text(
              lowSeverityErrors.first.message,
              style: TextStyle(
                color: Colors.blue[700],
                fontSize: 14,
              ),
            ),
          ),
          IconButton(
            onPressed: () {
              ref.read(errorProvider.notifier).removeError(lowSeverityErrors.first.id);
            },
            icon: Icon(
              Icons.close,
              color: Colors.blue[700],
              size: 20,
            ),
          ),
        ],
      ),
    );
  }
}

/// 错误重试组件
class ErrorRetryWidget extends StatelessWidget {
  final String message;
  final VoidCallback onRetry;
  final IconData? icon;

  const ErrorRetryWidget({
    super.key,
    required this.message,
    required this.onRetry,
    this.icon,
  });

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(
            icon ?? Icons.error_outline,
            size: 64,
            color: Colors.grey[400],
          ),
          const SizedBox(height: 16),
          Text(
            message,
            style: Theme.of(context).textTheme.bodyLarge?.copyWith(
              color: Colors.grey[600],
            ),
            textAlign: TextAlign.center,
          ),
          const SizedBox(height: 16),
          ElevatedButton.icon(
            onPressed: onRetry,
            icon: const Icon(Icons.refresh),
            label: const Text('重试'),
          ),
        ],
      ),
    );
  }
}