mail-hub/lib/ui/widgets/account_avatar.dart

import 'package:flutter/material.dart';

/// 账户头像（首字母 + 主题色）
class AccountAvatar extends StatelessWidget {
  final String name;
  final Color color;
  final double size;

  const AccountAvatar({
    super.key,
    required this.name,
    required this.color,
    this.size = 32,
  });

  @override
  Widget build(BuildContext context) {
    final letter = name.trim().isNotEmpty ? name.trim()[0].toUpperCase() : '?';
    return Container(
      width: size,
      height: size,
      decoration: BoxDecoration(
        color: color,
        shape: BoxShape.circle,
      ),
      alignment: Alignment.center,
      child: Text(
        letter,
        style: TextStyle(
          color: Colors.white,
          fontWeight: FontWeight.bold,
          fontSize: size * 0.45,
        ),
      ),
    );
  }
}

/// 邮箱地址大写首字母
String avatarLetter(String email) {
  final name = email.split('@').first;
  return name.isNotEmpty ? name[0].toUpperCase() : '?';
}