import 'package:flutter/material.dart';

/// 各主页面共用的占位内容：一个图标、一句标题和可选说明。
///
/// 页面接上真实业务后可以直接替换掉。
class EmptyState extends StatelessWidget {
  const EmptyState({
    required this.icon,
    required this.title,
    this.message,
    super.key,
  });

  final IconData icon;
  final String title;
  final String? message;

  @override
  Widget build(BuildContext context) {
    final ThemeData theme = Theme.of(context);
    final String? message = this.message;

    return Center(
      child: Padding(
        padding: const EdgeInsets.symmetric(horizontal: 32),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: <Widget>[
            Icon(icon, size: 56, color: theme.colorScheme.primary),
            const SizedBox(height: 16),
            Text(
              title,
              style: theme.textTheme.titleMedium,
              textAlign: TextAlign.center,
            ),
            if (message != null) ...<Widget>[
              const SizedBox(height: 8),
              Text(
                message,
                style: theme.textTheme.bodyMedium?.copyWith(
                  color: theme.colorScheme.onSurfaceVariant,
                ),
                textAlign: TextAlign.center,
              ),
            ],
          ],
        ),
      ),
    );
  }
}