<?php
/**
 * ZenTaoPHP的baseHelper类。
 * The baseHelper class file of ZenTaoPHP framework.
 *
 * @package framework
 *
 * The author disclaims copyright to this source code. In place of
 * a legal notice, here is a blessing:
 * 
 *  May you do good and not evil.
 *  May you find forgiveness for yourself and forgive others.
 *  May you share freely, never taking more than you give.
 */
class baseHelper
{
    /**
     * 设置一个对象的成员变量。
     * Set the member's value of one object.
     * <code>
     * <?php
     * $lang->db->user = 'wwccss';
     * helper::setMember('lang', 'db.user', 'chunsheng.wang');
     * ?>
     * </code>
     * @param string    $objName    the var name of the object.
     * @param string    $key        the key of the member, can be parent.child.
     * @param mixed     $value      the value to be set.
     * @static
     * @access public
     * @return bool
     */
    static public function setMember($objName, $key, $value)
    {
        global $$objName;
        if(!is_object($$objName) or empty($key)) return false;
        $key   = str_replace('.', '->', $key);
        $value = serialize($value);
        $code  = ("\$${objName}->{$key}=unserialize(<<<EOT\n$value\nEOT\n);");
        eval($code);
        return true;
    }

    /**
     * 生成一个模块方法的链接。control类的createLink实际上调用的是这个方法。
     * Create a link to a module's method, mapped in control class to call conveniently.
     *
     * <code>
     * <?php
     * helper::createLink('hello', 'index', 'var1=value1&var2=value2');
     * helper::createLink('hello', 'index', array('var1' => 'value1', 'var2' => 'value2');
     * ?>
     * </code>
     * @param string       $moduleName     module name, can pass appName like app.module.
     * @param string       $methodName     method name
     * @param string|array $vars           the params passed to the method, can be array('key' => 'value') or key1=value1&key2=value2) or key1=value1&key2=value2
     * @param string       $viewType       the view type
     * @param bool         $onlyBody       pass onlyBody=yes to the link thus the app can control the header and footer hide or show..
     * @static
     * @access public
     * @return string the link string.
     */
    static public function createLink($moduleName, $methodName = 'index', $vars = '', $viewType = '', $onlyBody = false, $programID = 0)
    {
        /* 设置$appName和$moduleName。Set appName and moduleName. */
        global $app, $config;
        $programID = $programID ? $programID : $app->session->program;
        if(strpos($moduleName, '.') !== false) 
        {
            list($appName, $moduleName) = explode('.', $moduleName);
        }
        else
        {
            $appName = $app->getAppName();
        }
        if(!empty($appName)) $appName .= '/';

        /* 处理$viewType和$vars。Set $viewType and $vars. */
        if(empty($viewType)) $viewType = $app->getViewType();
        if(!is_array($vars)) parse_str($vars, $vars);

        /* 生成url链接的开始部分。Set the begin parts of the link. */
        if($config->requestType == 'PATH_INFO')  $link = $config->webRoot . $appName;
        if($config->requestType != 'PATH_INFO')  $link = $config->webRoot . $appName . basename($_SERVER['SCRIPT_NAME']);
        if($config->requestType == 'PATH_INFO2') $link .= '/';

        /**
         * #1: RequestType为GET。When the requestType is GET. 
         * Input: moduleName=article&methodName=index&var1=value1. Output: ?m=article&f=index&var1=value1.
         *
         */
        if($config->requestType == 'GET')
        {
            $link .= "?{$config->moduleVar}=$moduleName&{$config->methodVar}=$methodName";
            if($viewType != 'html') $link .= "&{$config->viewVar}=" . $viewType;
            foreach($vars as $key => $value) $link .= "&$key=$value";

            $link = self::processOnlyBodyParam($link, $onlyBody);
            return self::processProgramParam($link, $programID, $onlyBody);
        }

        /**
         * #2: 方法名不是默认值或者是默认值，但有传参。MethodName equals the default method or vars not empty. 
         * Input: moduleName=article&methodName=view. Output: article-view.html
         * Input: moduleName=article&methodName=view. Output: article-index-abc.html
         *
         */
        if($methodName != $config->default->method or !empty($vars))
        {
            $link .= "$moduleName{$config->requestFix}$methodName";
            foreach($vars as $value) $link .= "{$config->requestFix}$value";
            $link .= '.' . $viewType;

            $link = self::processOnlyBodyParam($link, $onlyBody);
            return self::processProgramParam($link, $programID, $onlyBody);
        }

        /**
         * #3: 方法名为默认值且没有传参且模块名为默认值。MethodName is the default and moduleName is default and vars empty. 
         * Input: moduleName=index&methodName=index. Output: index.html
         *
         */
        if($moduleName == $config->default->module)
        {
            $link .= $config->default->method . '.' . $viewType; 
            $link  = self::processOnlyBodyParam($link, $onlyBody);
            return self::processProgramParam($link, $programID, $onlyBody);
        }

        /**
         * #4: 方法名为默认值且没有传参且模块名不为默认值，viewType和app指定的相等。MethodName is default but moduleName not and viewType equal app's viewType.. 
         * Input: moduleName=article&methodName=index&viewType=html. Output: /article/
         *
         */
        if($viewType == $app->getViewType())
        {
            $link .= $moduleName . '/';
            $link  = self::processOnlyBodyParam($link, $onlyBody);
            return self::processProgramParam($link, $programID, $onlyBody);
        }

        /**
         * #5: 方法名为默认值且没有传参且模块名不为默认值，viewType有另外指定。MethodName is default but moduleName not and viewType no equls app's viewType. 
         * Input: moduleName=article&methodName=index&viewType=json. Output: /article.json
         *
         */
        $link .= $moduleName . '.' . $viewType;
        $link  = self::processOnlyBodyParam($link, $onlyBody);
        return self::processProgramParam($link, $programID, $onlyBody);
    }

    /**
     *  处理program 参数。
     *  Process the programID param in url.
     * 
     *  如果传参的时候设定了$programID，在生成链接的时候继续追加。
     *  If $progrmID in the url, append it to the link.
     *  
     *  @param  string  $link 
     *  @param  int     $programID
     *  @param  bool    $onlybody
     *  @static
     *  @access public
     *  @return string
     */
    public static function processProgramParam($link, $programID = '', $onlybody = false)
    {
        global $config;
        if(!$programID) return $link;
        if($onlybody)
        {
            $link .= $config->requestType != 'GET' ? "&pgm=$programID" : "&pgm=$programID";
        }
        else
        {
            $link .= $config->requestType != 'GET' ? "?pgm=$programID" : "&pgm=$programID";
        }

        return $link;
    }

    /**
     * 处理onlyBody 参数。
     * Process the onlyBody param in url.
     *
     * 如果传参的时候设定了$onlyBody为真，或者当前页面请求中包含了onlybody=yes，在生成链接的时候继续追加。
     * If $onlyBody set to true or onlybody=yes in the url, append onlyBody param to the link.
     * 
     * @param  string  $link 
     * @param  bool    $onlyBody 
     * @static
     * @access public
     * @return string
     */
    public static function processOnlyBodyParam($link, $onlyBody = false)
    {
        global $config;
        if(!$onlyBody and !self::inOnlyBodyMode()) return $link;
        $onlybodyString = $config->requestType != 'GET' ? "?onlybody=yes" : "&onlybody=yes";
        return $link . $onlybodyString;
    }

    /**
     * 检查是否是onlybody模式。
     * Check in only body mode or not.
     * 
     * @access public
     * @return void
     */
    public static function inOnlyBodyMode()
    {
        return (isset($_GET['onlybody']) and $_GET['onlybody'] == 'yes');
    }

    /**
     * 使用helper::import()来引入文件，不要直接使用include或者require. 
     * Using helper::import() to import a file, instead of include or require.
     *
     * @param string    $file   the file to be imported.
     * @static
     * @access public
     * @return bool
     */
    static public function import($file)
    {
        $file = realpath($file);
        if(!is_file($file)) return false;

        static $includedFiles = array();
        if(!isset($includedFiles[$file]))
        {
            include $file;
            $includedFiles[$file] = true;
            return true;
        }

        return true;
    }

    /**
     * 将数组或者列表转化成 IN( 'a', 'b') 的形式。
     * Convert a list to  IN('a', 'b') string.
     * 
     * @param   string|array $idList   列表，可以是数组或者用逗号隔开的列表。The id lists, can be a array or a string joined with comma.
     * @static
     * @access  public
     * @return  string  the string like IN('a', 'b').
     */
    static public function dbIN($idList)
    {
        if(is_array($idList)) 
        {
            if(!function_exists('get_magic_quotes_gpc') or !get_magic_quotes_gpc())
            {
                foreach($idList as $key=>$value) $idList[$key] = addslashes($value); 
            }
            return "IN ('" . join("','", $idList) . "')";
        }

        if(!function_exists('get_magic_quotes_gpc') or !get_magic_quotes_gpc()) $idList = addslashes($idList);
        return "IN ('" . str_replace(',', "','", str_replace(' ', '', $idList)) . "')";
    }

    /**
     * 安全的Base64编码，框架对'/'字符比较敏感，转换为'.'。
     * Create safe base64 encoded string for the framework.
     * 
     * @param   string  $string   the string to encode.
     * @static
     * @access  public
     * @return  string  encoded string.
     */
    static public function safe64Encode($string)
    {
        return strtr(base64_encode($string), '/', '.');
    }

    /**
     * 解码base64，先将之前的'.' 转换回'/'
     * Decode the string encoded by safe64Encode.
     * 
     * @param   string  $string   the string to decode
     * @static
     * @access  public
     * @return  string  decoded string.
     */
    static public function safe64Decode($string)
    {
        return base64_decode(strtr($string, '.', '/'));
    }

    /**
     * JSON编码，自动处理转义的问题。
     * JSON encode, process the slashes.
     * 
     * @param   mixed  $data   the object to encode
     * @static
     * @access  public
     * @return  string  decoded string.
     */
    static public function jsonEncode($data)
    {
        return (function_exists('get_magic_quotes_gpc') and get_magic_quotes_gpc()) ? addslashes(json_encode($data)) : json_encode($data);
    }

    /**
     * 判断是否是utf8编码
     * Judge a string is utf-8 or not.
     * 
     * @author hmdker@gmail.com
     * @param  string    $string 
     * @see    http://php.net/manual/en/function.mb-detect-encoding.php
     * @static
     * @access public
     * @return bool
     */
    static public function isUTF8($string)
    {
        $c    = 0; 
        $b    = 0;
        $bits = 0;
        $len  = strlen($string);
        for($i=0; $i<$len; $i++)
        {
            $c = ord($string[$i]);
            if($c > 128)
            {
                if(($c >= 254)) return false;
                elseif($c >= 252) $bits=6;
                elseif($c >= 248) $bits=5;
                elseif($c >= 240) $bits=4;
                elseif($c >= 224) $bits=3;
                elseif($c >= 192) $bits=2;
                else return false;
                if(($i+$bits) > $len) return false;
                while($bits > 1)
                {
                    $i++;
                    $b=ord($string[$i]);
                    if($b < 128 || $b > 191) return false;
                    $bits--;
                }
            }
        }
        return true;
    }

    /**
     * 去掉UTF-8 Bom头。
     * Remove UTF-8 Bom.
     * 
     * @param  string    $string
     * @access public
     * @return string
     */
    public static function removeUTF8Bom($string)
    {
        if(substr($string, 0, 3) == pack('CCC', 239, 187, 191)) return substr($string, 3);
        return $string;
    }

    /**
     * 增强substr方法：支持多字节语言，比如中文。
     * Enhanced substr version: support multibyte languages like Chinese.
     *
     * @param string    $string
     * @param int       $length 
     * @param string    $append 
     * @return string 
     */
    public static function substr($string, $length, $append = '')
    {
        $rawString = $string;

        if(function_exists('mb_substr')) $string = mb_substr($string, 0, $length, 'utf-8');

        preg_match_all("/./su", $string, $data);
        $string = join("", array_slice($data[0],  0, $length));

        return ($string != $rawString) ? $string . $append : $string;
    }

    /**
     * Get browser name and version.
     * 
     * @access public
     * @return array
     */
    public static function getBrowser()
    {
        $browser = array('name'=>'unknown', 'version'=>'unknown');

        if(empty($_SERVER['HTTP_USER_AGENT'])) return $browser;

        $agent = $_SERVER["HTTP_USER_AGENT"];

        /* Chrome should checked before safari.*/
        if(strpos($agent, 'Firefox') !== false) $browser['name'] = "firefox";
        if(strpos($agent, 'Opera') !== false)   $browser['name'] = 'opera';
        if(strpos($agent, 'Safari') !== false)  $browser['name'] = 'safari';
        if(strpos($agent, 'Chrome') !== false)  $browser['name'] = "chrome";

        // Check the name of browser
        if(strpos($agent, 'MSIE') !== false || strpos($agent, 'rv:11.0')) $browser['name'] = 'ie';
        if(strpos($agent, 'Edge') !== false) $browser['name'] = 'edge';

        // Check the version of browser
        if(preg_match('/MSIE\s(\d+)\..*/i', $agent, $regs))       $browser['version'] = $regs[1];
        if(preg_match('/FireFox\/(\d+)\..*/i', $agent, $regs))    $browser['version'] = $regs[1];
        if(preg_match('/Opera[\s|\/](\d+)\..*/i', $agent, $regs)) $browser['version'] = $regs[1];
        if(preg_match('/Chrome\/(\d+)\..*/i', $agent, $regs))     $browser['version'] = $regs[1];

        if((strpos($agent, 'Chrome') == false) && preg_match('/Safari\/(\d+)\..*$/i', $agent, $regs)) $browser['version'] = $regs[1];
        if(preg_match('/rv:(\d+)\..*/i', $agent, $regs)) $browser['version'] = $regs[1];
        if(preg_match('/Edge\/(\d+)\..*/i', $agent, $regs)) $browser['version'] = $regs[1];

        return $browser;
    }

    /**
     * Get client os from agent info. 
     * 
     * @static
     * @access public
     * @return string
     */
    public static function getOS()
    {
        if(empty($_SERVER['HTTP_USER_AGENT'])) return 'unknow';

        $osList = array();
        $osList['/windows nt 10/i']      = 'Windows 10';
        $osList['/windows nt 6.3/i']     = 'Windows 8.1';
        $osList['/windows nt 6.2/i']     = 'Windows 8';
        $osList['/windows nt 6.1/i']     = 'Windows 7';
        $osList['/windows nt 6.0/i']     = 'Windows Vista';
        $osList['/windows nt 5.2/i']     = 'Windows Server 2003/XP x64';
        $osList['/windows nt 5.1/i']     = 'Windows XP';
        $osList['/windows xp/i']         = 'Windows XP';
        $osList['/windows nt 5.0/i']     = 'Windows 2000';
        $osList['/windows me/i']         = 'Windows ME';
        $osList['/win98/i']              = 'Windows 98';
        $osList['/win95/i']              = 'Windows 95';
        $osList['/win16/i']              = 'Windows 3.11';
        $osList['/macintosh|mac os x/i'] = 'Mac OS X';
        $osList['/mac_powerpc/i']        = 'Mac OS 9';
        $osList['/linux/i']              = 'Linux';
        $osList['/ubuntu/i']             = 'Ubuntu';
        $osList['/iphone/i']             = 'iPhone';
        $osList['/ipod/i']               = 'iPod';
        $osList['/ipad/i']               = 'iPad';
        $osList['/android/i']            = 'Android';
        $osList['/blackberry/i']         = 'BlackBerry';
        $osList['/webos/i']              = 'Mobile';

        foreach ($osList as $regex => $value)
        { 
            if(preg_match($regex, $_SERVER['HTTP_USER_AGENT'])) return $value; 
        }   

        return 'unknown';
    }
    
    /**
     *  计算两个日期相差的天数，取整。
     *  Compute the diff days of two date.
     * 
     * @param   string $date1   the first date.
     * @param   string $date2   the sencond date.
     * @access  public
     * @return  int  the diff of the two days.
     */
    static public function diffDate($date1, $date2)
    {
        return round((strtotime($date1) - strtotime($date2)) / 86400, 0);
    }

    /**
     *  获取当前时间，使用common语言文件定义的DT_DATETIME1常量。
     *  Get now time use the DT_DATETIME1 constant defined in the lang file.
     * 
     * @access  public
     * @return  datetime  now
     */
    static public function now()
    {
        return date(DT_DATETIME1);
    }

    /**
     *  获取当前日期，使用common语言文件定义的DT_DATE1常量。
     *  Get today according to the  DT_DATE1 constant defined in the lang file.
     *
     * @access  public
     * @return  date  today
     */
    static public function today()
    {
        return date(DT_DATE1);
    }

    /**
     *  获取当前日期，使用common语言文件定义的DT_TIME1常量。
     *  Get now time use the DT_TIME1 constant defined in the lang file.
     * 
     * @access  public
     * @return  date  today
     */
    static public function time()
    {
        return date(DT_TIME1);
    }

    /**
     *  判断日期是不是零。
     *  Judge a date is zero or not.
     * 
     * @access  public
     * @return  bool
     */
    static public function isZeroDate($date)
    {
        return substr($date, 0, 4) == '0000';
    }

    /**
     *  列出目录中符合该正则表达式的文件。
     *  Get files match the pattern under a directory.
     * 
     * @access  public
     * @return  array   the files match the pattern
     */
    static public function ls($dir, $pattern = '')
    {
        if(empty($dir)) return array();

        $files = array();
        $dir   = realpath($dir);
        if(is_dir($dir)) $files = glob($dir . DIRECTORY_SEPARATOR . '*' . $pattern);
        return empty($files) ? array() : $files;
    }

    /**
     * 切换目录。第一次调用的时候记录当前的路径，再次调用的时候切换回之前的路径。
     * Change directory: first call, save the $cwd, secend call, change to $cwd.
     * 
     * @param  string $path 
     * @static
     * @access public
     * @return void
     */
    static function cd($path = '')
    {
        static $cwd = '';
        if($path) $cwd = getcwd();
        !empty($path) ? chdir($path) : chdir($cwd);
    }

    /**
     * 通过域名获取站点代号。
     * Get siteCode for a domain.
     *
     * www.xirang.com => xirang
     * xirang.com     => xirang
     * xirang.com.cn  => xirang
     * xirang.cn      => xirang
     * xirang         => xirang
     *
     * @param  string $domain
     * @return string $siteCode
     **/ 
    public static function parseSiteCode($domain)
    {
        global $config;

        /* 去除域名中的端口部分。Remove the port part of the domain. */
        if(strpos($domain, ':') !== false) $domain = substr($domain, 0, strpos($domain, ':'));
        $domain = strtolower($domain);

        /* $config里面有定义或者是localhost，直接返回。 Return directly if defined in $config or is localhost. */
        if(isset($config->siteCodeList[$domain])) return $config->siteCodeList[$domain];
        if($domain == 'localhost') return $domain;

        /* 将域名中的-改为_。Replace '-' with '_' in the domain. */
        $domain = str_replace('-', '_', $domain);
        $items  = explode('.', $domain);

        /* 类似a.com的形式。 Domain like a.com. */
        $postfix = str_replace($items[0] . '.', '', $domain);
        if(isset($config->domainPostfix) and strpos($config->domainPostfix, "|$postfix|") !== false) return $items[0];

        /* 类似www.a.com的形式。 Domain like www.a.com. */
        $postfix = str_replace($items[0] . '.' . $items[1] . '.', '', $domain);
        if(isset($config->domainPostfix) and strpos($config->domainPostfix, "|$postfix|") !== false) return $items[1];

        /* 类似xxx.sub.a.com的形式。 Domain like xxx.sub.a.com. */
        $postfix = str_replace($items[0] . '.' . $items[1] . '.' . $items[2] . '.', '', $domain);
        if(isset($config->domainPostfix) and strpos($config->domainPostfix, "|$postfix|") !== false) return $items[0];

        return '';
    }

    /**
     * 检查是否是AJAX请求。
     * Check is ajax request.
     * 
     * @static
     * @access public
     * @return bool
     */
    public static function isAjaxRequest()
    {
        if(isset($_SERVER['HTTP_X_REQUESTED_WITH']) && $_SERVER['HTTP_X_REQUESTED_WITH'] == 'XMLHttpRequest') return true;
        if(isset($_GET['HTTP_X_REQUESTED_WITH'])    && $_GET['HTTP_X_REQUESTED_WITH']    == 'XMLHttpRequest') return true;
        return false;
    }

    /**
     * 301跳转。
     * Header 301 Moved Permanently.
     * 
     * @param  string    $locate 
     * @access public
     * @return void
     */
    public static function header301($locate)
    {
        header('HTTP/1.1 301 Moved Permanently');
        die(header('Location:' . $locate));
    }

    /** 
     * 获取远程IP。
     * Get remote ip. 
     * 
     * @access public
     * @return string
     */
    public static function getRemoteIp()
    {
        $ip = '';
        if(!empty($_SERVER["REMOTE_ADDR"]))          $ip = $_SERVER["REMOTE_ADDR"];
        if(!empty($_SERVER["HTTP_X_FORWARDED_FOR"])) $ip = $_SERVER["HTTP_X_FORWARDED_FOR"];
        if(!empty($_SERVER['HTTP_CLIENT_IP']))       $ip = $_SERVER['HTTP_CLIENT_IP'];

        return $ip;
    }

    /**
     * Restart session.
     * 
     * @param  string $sessionID 
     * @static
     * @access public
     * @return void
     */
    public static function restartSession($sessionID = '')
    {
        if(empty($sessionID)) $sessionID = sha1(mt_rand());

        session_write_close();
        session_id($sessionID);
        session_start();
    }
}

//------------------------------- 常用函数。Some tool functions.-------------------------------//

/**
 *  helper::createLink()的别名，方便创建本模块方法的链接。
 *  The short alias of helper::createLink() method to create link to control method of current module.
 *
 * @param  string        $methodName  the method name
 * @param  string|array  $vars        the params passed to the method, can be array('key' => 'value') or key1=value1&key2=value2)
 * @param  string        $viewType    
 * @return string the link string.
 */
function inLink($methodName = 'index', $vars = '', $viewType = '')
{
    global $app;
    return helper::createLink($app->getModuleName(), $methodName, $vars, $viewType);
}

/**
 *  通过一个静态游标，可以遍历数组。
 *  Static cycle a array.
 *
 * @param array  $items     the array to be cycled.
 * @return mixed
 */
function cycle($items)
{
    static $i = 0;
    if(!is_array($items)) $items = explode(',', $items);
    if(!isset($items[$i])) $i = 0;
    return $items[$i++];
}

/**
 * 获取当前时间的Unix时间戳，精确到微妙。
 * Get current microtime.
 * 
 * @access public
 * @return float current time.
 */
function getTime()
{
    list($usec, $sec) = explode(" ", microtime());
    return ((float)$usec + (float)$sec);
}

/**
 * 打印变量的信息
 * dump a var.
 * 
 * @param mixed $var 
 * @access public
 * @return void
 */
function a($var)
{
    echo "<xmp class='a-left'>";
    print_r($var);
    echo "</xmp>";
}

/**
 * 判断是否内外IP。
 * Judge the server ip is local or not.
 *
 * @access public
 * @return void
 */
function isLocalIP()
{
    global $config;
    if(isset($config->islocalIP)) return $config->isLocalIP;
    $serverIP = $_SERVER['SERVER_ADDR'];
    if($serverIP == '127.0.0.1' or $serverIP == '::1') return true;
    if(strpos($serverIP, '10.70') !== false) return false;
    return !filter_var($serverIP, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE);
}

/**
 * 获取webRoot。
 * Get web root. 
 * 
 * @access public
 * @return string 
 */
function getWebRoot($full = false)
{
    $path = $_SERVER['SCRIPT_NAME'];

    if(PHP_SAPI == 'cli')
    {
        if(isset($_SERVER['argv'][1]))
        {
            $url  = parse_url($_SERVER['argv'][1]);
            $path = empty($url['path']) ? '/' : rtrim($url['path'], '/');
        }
        $path = empty($path) ? '/' : preg_replace('/\/www$/', '/www/', $path);
    }
    
    if($full)
    {
        $http = (isset($_SERVER['HTTPS']) and strtolower($_SERVER['HTTPS']) != 'off') ? 'https://' : 'http://';
        return $http . $_SERVER['HTTP_HOST'] . substr($path, 0, (strrpos($path, '/') + 1));
    }

    $path = substr($path, 0, (strrpos($path, '/') + 1));
    $path = str_replace('\\', '/', $path);
    return $path;
}

/**
 * 当数组/对象变量$var存在$key项时，返回存在的对应值或设定值，否则返回$key或不存在的设定值。
 * When the $var has the $key, return it, esle result one default value.
 * 
 * @param  array|object    $var 
 * @param  string|int      $key 
 * @param  mixed           $valueWhenNone     value when the key not exits.
 * @param  mixed           $valueWhenExists   value when the key exits.
 * @access public
 * @return string
 */
function zget($var, $key, $valueWhenNone = false, $valueWhenExists = false)
{
    if(!is_array($var) and !is_object($var)) return false;

    $type = is_array($var) ? 'array' : 'object';
    $checkExists = $type == 'array' ? isset($var[$key]) : isset($var->$key);

    if($checkExists)
    {
        if($valueWhenExists !== false) return $valueWhenExists;
        return $type == 'array' ? $var[$key] : $var->$key;
    }

    if($valueWhenNone !== false) return $valueWhenNone;
    return $key;
}
