php 根据日期获取星座

/**
     * 根据日期获取星座
     * 星座是按阳历来计算的
     * $month 阳历月份
     * $day  阳历日期
     */
    public static function get_xingzuo($month, $day)
    {
        // 检查参数有效性
        if ($month < 1 || $month > 12 || $day < 1 || $day > 31)
        {
            return '';
        }

        // 星座名称以及开始结束日期
        $xingzuo_data = [
            [
                'name'=>'水瓶',
                'start_time'=>'01-21',
                'end_time'=>'02-19',
            ],
            [
                'name'=>'双鱼',
                'start_time'=>'02-20',
                'end_time'=>'03-20',
            ],
            [
                'name'=>'白羊',
                'start_time'=>'03-21',
                'end_time'=>'04-20',
            ],
            [
                'name'=>'金牛',
                'start_time'=>'04-21',
                'end_time'=>'05-21',
            ],
            [
                'name'=>'双子',
                'start_time'=>'05-22',
                'end_time'=>'06-21',
            ],
            [
                'name'=>'巨蟹',
                'start_time'=>'06-22',
                'end_time'=>'07-23',
            ],
            [
                'name'=>'狮子',
                'start_time'=>'07-24',
                'end_time'=>'08-23',
            ],
            [
                'name'=>'处女',
                'start_time'=>'08-24',
                'end_time'=>'09-23',
            ],
            [
                'name'=>'天秤',
                'start_time'=>'09-24',
                'end_time'=>'10-23',
            ],
            [
                'name'=>'天蝎',
                'start_time'=>'10-24',
                'end_time'=>'11-22',
            ],
            [
                'name'=>'射手',
                'start_time'=>'11-23',
                'end_time'=>'12-21',
            ],
            [
                'name'=>'摩羯',
                'start_time'=>'12-22',
                'end_time'=>'01-20',
            ],
        ];
        $year = date('Y');
        $user_time = strtotime("{$year}-{$month}-{$day} 00:00:00");
        $xingzuo = '';
        foreach ($xingzuo_data as $val){
            if($user_time >= strtotime("{$year}-{$val['start_time']} 00:00:00") && $user_time <= strtotime("{$year}-{$val['end_time']} 00:00:00") ){
                $xingzuo = $val['name'];
            }
        }
        return $xingzuo;

    }