/wind/utility/WindUtility.php

<?php

/**
 * 通用工具库
 *
 * @author Qiong Wu <papa0924@gmail.com>
 * @copyright ©2003-2103 phpwind.com
 * @license http://www.windframework.com
 * @version $Id$
 * @package utility
 */

class WindUtility {



	/**
	 * 解析表达式
	 * 
	 * 表达式格式: namespace:arg1.arg2.arg3.arg4.arg5==value
	 * 返回: array($namespace, $param1, $operator, $param1)
	 * 
	 * @param string $expression 待解析的表达式
	 * @return array 返回解析后的表达式,由表达式的各项组成的数组:
	 * <ul>
	 * <li>第一个元素: 命名空间</li>
	 * <li>第二个元素: 表达式的左边操作数</li>
	 * <li>第三个元素: 表达式的操作符</li>
	 * <li>第四个元素： 表达式的右边操作数</li>
	 * </ul>
	 */

	public static function resolveExpression($expression) {

		$operators = array('==', '!=', '<', '>', '<=', '>=');

		$operatorsReplace = array('#==#', '#!=#', '#<#', '#>#', '#<=#', '#>=#');

		list($p, $o, $v2) = explode('#', str_replace($operators, $operatorsReplace, $expression));

		if (strpos($p, ":") !== false)

			list($_namespace, $p) = explode(':', trim($p, ':'));

		else

			$_namespace = '';

		return array($_namespace, $p, $o, $v2);

	}



	/**
	 * 执行简单的条件表达式
	 * 
	 * 只能执行==、！=、<、>、<=、>=简单的比较
	 * 
	 * @param string $v1 左边的操作数
	 * @param string $v2 右边的操作数
	 * @param string $operator 操作符号
	 * @return boolean 
	 */

	public static function evalExpression($v1, $v2, $operator) {

		switch ($operator) {

			case '==':

				return $v1 == $v2;

			case '!=':

				return $v1 != $v2;

			case '<':

				return $v1 < $v2;

			case '>':

				return $v1 > $v2;

			case '<=':

				return $v1 <= $v2;

			case '>=':

				return $v1 >= $v2;

			default:

				return false;

		}

		return false;

	}



	/**
	 * 递归合并两个数组
	 * 
	 * @param array $array1 数组1
	 * @param array $array2  数组2
	 * @return array 合并后的数组
	 */

	public static function mergeArray($array1, $array2) {

		foreach ($array2 as $key => $value) {

			if (empty($value)) {

				$array1[$key] = $value;

			} else if (!isset($array1[$key])) {

				$array1[$key] = $value;

			} elseif (is_array($array1[$key]) && is_array($value)) {

				$array1[$key] = self::mergeArray($array1[$key], $array2[$key]);

			} elseif (is_numeric($key) && $array1[$key] !== $array2[$key]) {

				$array1[] = $value;

			} else

				$array1[$key] = $value;

		}

		return $array1;

	}



	/**
	 * 将字符串首字母小写
	 * 
	 * @param string $str 待处理的字符串 
	 * @return string 返回处理后的字符串
	 */

	public static function lcfirst($str) {

		$str[0] = strtolower($str[0]);

		return $str;

	}



	/**
	 * 获得随机数字符串
	 * 
	 * @param int $length 随机数的长度
	 * @return string 随机获得的字串
	 */

	public static function generateRandStr($length) {

		$randstr = "";

		for ($i = 0; $i < (int) $length; $i++) {

			$randnum = mt_rand(0, 61);

			if ($randnum < 10) {

				$randstr .= chr($randnum + 48);

			} else if ($randnum < 36) {

				$randstr .= chr($randnum + 55);

			} else {

				$randstr .= chr($randnum + 61);

			}

		}

		return $randstr;

	}



	/**
	 * 通用组装测试验证规则
	 * 
	 * @param string $field	 验证字段名称
	 * @param string $validator  验证方法
	 * @param array $args        验证方法中传递的其他参数,需在待验证字段值的后面,默认为空数组
	 * @param string $default	 验证失败是设置的默认值,默认为null
	 * @param string $message	 验证失败是返回的错误信息,默认为空字串
	 * @return array 返回验证规则
	 * <ul>
	 * <li>field: 验证字段名称</li>
	 * <li>validator: 验证方法</li>
	 * <li>args: 验证方法中传递的其他参数,需在待验证字段值的后面,缺省为空数组</li>
	 * <li>default: 验证失败是设置的默认值,缺省为null</li>
	 * <li>message: 验证失败是返回的错误信息,默认为'提示：XX验证失败'</li>
	 * </ul>
	 */

	public static function buildValidateRule($field, $validator, $args = array(), $default = null, $message = '') {

		return array(

			'field' => $field, 

			'validator' => $validator, 

			'args' => (array) $args, 

			'default' => $default, 

			'message' => ($message ? $message : '提示：\'' . $field . '\'验证失败'));

	}



	/**
	 * 对字符串中的参数进行替换
	 * 
	 * 该函优化了php strtr()实现, 在进行数组方式的字符替换时支持了两种模式的字符替换:
	 * @example<pre>
	 * 1. echo WindUtility::strtr("I Love {you}",array('{you}' => 'lili')); 
	 * 结果: I Love lili
	 * 2. echo WindUtility::strtr("I Love #0,#1",array('lili','qiong')); 
	 * 结果: I Love lili,qiong
	 * <pre>
	 * @see WindLangResource::getMessage()
	 * @param string $str
	 * @param string $from
	 * @param string $to 可选参数,默认值为''
	 * @return string
	 */

	public static function strtr($str, $from, $to = '') {

		if (is_string($from)) return strtr($str, $from, $to);

		if (isset($from[0])) {

			foreach ($from as $key => $value) {

				$from['#' . $key] = $value;

				unset($from[$key]);

			}

		}

		return !empty($from) ? strtr($str, $from) : $str;

	}



	/**

	 * 错误信息处理方法

	 *

	 * @param string $file

	 * @param string $line

	 * @param array $trace

	 */

	public static function crash($file, $line, $trace) {

		$msg = '';

		$count = count($trace);

		$padLen = strlen($count);

		foreach ($trace as $key => $call) {

			if (!isset($call['file']) || $call['file'] == '') {

				$call['file'] = '~Internal Location~';

				$call['line'] = 'N/A';

			}

			$traceLine = '#' . str_pad(($count - $key), $padLen, "0", STR_PAD_LEFT) . '  ' . self::getCallLine(

				$call);

			$trace[$key] = $traceLine;

		}

		$fileLines = array();

		if (is_file($file)) {

			$currentLine = $line - 1;

			$fileLines = explode("\n", file_get_contents($file, null, null, 0, 10000000));

			$topLine = $currentLine - 5;

			$fileLines = array_slice($fileLines, $topLine > 0 ? $topLine : 0, 10, true);

			if (($count = count($fileLines)) > 0) {

				$padLen = strlen($count);

				foreach ($fileLines as $line => &$fileLine)

					$fileLine = " " . htmlspecialchars(

						str_pad($line + 1, $padLen, "0", STR_PAD_LEFT) . ": " . str_replace("\t", 

							"    ", rtrim($fileLine)), null, "UTF-8");

			}

		}

		return array($fileLines, $trace);

	}



	/**

	 * @param array $call

	 * @return string

	 */

	private static function getCallLine($call) {

		$call_signature = "";

		if (isset($call['file'])) $call_signature .= $call['file'] . " ";

		if (isset($call['line'])) $call_signature .= "(" . $call['line'] . ") ";

		if (isset($call['function'])) {

			$call_signature .= $call['function'] . "(";

			if (isset($call['args'])) {

				foreach ($call['args'] as $arg) {

					if (is_string($arg))

						$arg = '"' . (strlen($arg) <= 64 ? $arg : substr($arg, 0, 64) . "…") . '"';

					else if (is_object($arg))

						$arg = "[Instance of '" . get_class($arg) . "']";

					else if ($arg === true)

						$arg = "true";

					else if ($arg === false)

						$arg = "false";

					else if ($arg === null)

						$arg = "null";

					else

						$arg = strval($arg);

					$call_signature .= $arg . ',';

				}

			}

			$call_signature = trim($call_signature, ',') . ")";

		}

		return $call_signature;

	}

}