class DateFormatter {
  /// 格式化日期显示
  static String formatDate(DateTime date) {
    final now = DateTime.now();
    final today = DateTime(now.year, now.month, now.day);
    final dateToCheck = DateTime(date.year, date.month, date.day);
    final difference = today.difference(dateToCheck).inDays;

    // 格式化日期部分
    String dateStr;
    if (date.year == now.year) {
      // 当年日期显示 月-日
      dateStr = '${_padZero(date.month)}-${_padZero(date.day)}';
    } else {
      // 非当年日期显示 年-月-日
      dateStr = '${date.year}-${_padZero(date.month)}-${_padZero(date.day)}';
    }

    // 获取提示文案
    String hint;
    switch (difference) {
      case 0:
        hint = '今天';
        break;
      case 1:
        hint = '昨天';
        break;
      case 2:
        hint = '前天';
        break;
      default:
        // 获取星期几
        hint = _getWeekDay(date);
    }

    return '$dateStr   $hint';
  }

  /// 数字补零
  static String _padZero(int number) {
    return number.toString().padLeft(2, '0');
  }

  /// 获取星期几
  static String _getWeekDay(DateTime date) {
    final weekDays = ['周日', '周一', '周二', '周三', '周四', '周五', '周六'];
    return weekDays[date.weekday % 7];
  }
}