<?php
/**
 * Created by Liang
 * Email: 1144828910@qq.com
 * User: joila
 * Date: 2020/7/20
 * Time: 上午10:52
 */


namespace FilterData;

/**
 * 筛选身份证号码
 * Class FilterIdCard
 * @package FilterData
 */
class FilterIdCard
{

    /**
     * 调用方法
     *
     * @param string $IdCard
     *
     * @return bool
     */
    public static function MethodValidationFilterIdCard(string $IdCard) {
        if (strlen($IdCard) == 18) {
            return self::MethodIdCardChecksum18($IdCard);
        } elseif (( strlen($IdCard) == 15 )) {
            $IdCard = self::MethodIdCard15to18($IdCard);
            return self::MethodIdCardChecksum18($IdCard);
        } else {
            return false;
        }
    }

    /**
     * 计算身份证校验码，根据国家标准GB 11643-1999
     *
     * @param string $IdCardBase
     *
     * @return bool|mixed
     */
    protected static function MethodIdCardVerifyNumber(string $IdCardBase) {
        if (strlen($IdCardBase) != 17) {
            return false;
        }
        //加权因子
        $factor = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2];
        //校验码对应值
        $verify_number_list = ['1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2'];
        $checksum           = 0;
        for ($i = 0; $i < strlen($IdCardBase); $i++) {
            $checksum += substr($IdCardBase, $i, 1) * $factor[$i];
        }
        $mod = $checksum % 11;
        return $verify_number_list[$mod];
    }

    /**
     * 将15位身份证升级到18位
     *
     * @param string $IdCard
     *
     * @return bool|string
     */
    protected static function MethodIdCard15to18(string $IdCard) {
        if (strlen($IdCard) != 15) {
            return false;
        } else {
            // 如果身份证顺序码是996 997 998 999，这些是为百岁以上老人的特殊编码
            if (array_search(substr($IdCard, 12, 3), ['996', '997', '998', '999']) !== false) {
                $IdCard = substr($IdCard, 0, 6) . '18' . substr($IdCard, 6, 9);
            } else {
                $IdCard = substr($IdCard, 0, 6) . '19' . substr($IdCard, 6, 9);
            }
        }
        $IdCard = $IdCard . self::MethodIdCardVerifyNumber($IdCard);
        return $IdCard;
    }

    // 18位身份证校验码有效性检查
    protected static function MethodIdCardChecksum18(string $IdCard) {
        if (strlen($IdCard) != 18) {
            return false;
        }
        $IdCardBase = substr($IdCard, 0, 17);
        if (self::MethodIdCardVerifyNumber($IdCardBase) != strtoupper(substr($IdCard, 17, 1))) {
            return false;
        } else {
            return true;
        }
    }
}