WordPress like shortcode parser for PHP

gistfile1.php

<?php
//The content which should be parsed
$content = '<p>Hello, my name is John an my age is [calc-age day="4" month="10" year="1991"].</p>';
$content .= '<p>Hello, my name is Carol an my age is [calc-age day="26" month="11" year="1996"].</p>';

//The array with all the shortcode handlers. This is just a regular associative array with anonymous functions as values. A very cool new feature in PHP, just like callbacks in JavaScript or delegates in C#.
$shortcodes = array(
	"calc-age" => function($data){
		$content = "";
		//Calculate the age
		if(isset($data["day"], $data["month"], $data["year"])){
			$age = date("Y") - $data["year"];
			if(date("m") < $data["month"]){
				$age--;
			}
			if(date("m") == $data["month"] && date("d") < $data["day"]){
				$age--;
			}
			$content = $age;
		}
		return $content;
	}
);
//http://stackoverflow.com/questions/18196159/regex-extract-variables-from-shortcode
function handleShortcodes($content, $shortcodes){
	//Loop through all shortcodes
	foreach($shortcodes as $key => $function){
		$dat = array();
		preg_match_all("/\[".$key." (.+?)\]/", $content, $dat);
		if(count($dat) > 0 && $dat[0] != array() && isset($dat[1])){
			$i = 0;
			$actual_string = $dat[0];
			foreach($dat[1] as $temp){
				$temp = explode(" ", $temp);
				$params = array();
				foreach ($temp as $d){
					list($opt, $val) = explode("=", $d);
					$params[$opt] = trim($val, '"');
				}
				$content = str_replace($actual_string[$i], $function($params), $content);
				$i++;
			}
		}
	}
	return $content;
}
echo handleShortcodes($content, $shortcodes);
?>

Nice little piece of code - works great with one exception. You can't create a parameter less shortcode for example. [show-list]. This won't work until you add a dummy parameter such as [show-list sc="1"]. Not a huge deal but would be nice. Took a quick look at it but wasn't sure how to make that work.

Nice code! How would this work though with spaces in attribute values such as [data att="Some Attribute"] ?

Did some modification and got it working with this
`foreach($shortcodes as $key => $function){
$dat = array();
preg_match_all("/[".$key." (.+?)]/", $content, $dat);
if(count($dat) > 0 && $dat[0] != array() && isset($dat[1])){
$i = 0;
$actual_string = $dat[0];

            foreach($dat[1] as $temp){

                $atts    = array();
                $pattern = '/([\w-]+)\s*=\s*"([^"]*)"(?:\s|$)|([\w-]+)\s*=\s*\'([^\']*)\'(?:\s|$)|([\w-]+)\s*=\s*([^\s\'"]+)(?:\s|$)|"([^"]*)"(?:\s|$)|\'([^\']*)\'(?:\s|$)|(\S+)(?:\s|$)/';
                $text    = preg_replace( "/[\x{00a0}\x{200b}]+/u", ' ', $temp );
                if ( preg_match_all( $pattern, $text, $match, PREG_SET_ORDER ) ) {
                    foreach ( $match as $m ) {
                        if ( ! empty( $m[1] ) ) {
                            $atts[ strtolower( $m[1] ) ] = stripcslashes( $m[2] );
                        } elseif ( ! empty( $m[3] ) ) {
                            $atts[ strtolower( $m[3] ) ] = stripcslashes( $m[4] );
                        } elseif ( ! empty( $m[5] ) ) {
                            $atts[ strtolower( $m[5] ) ] = stripcslashes( $m[6] );
                        } elseif ( isset( $m[7] ) && strlen( $m[7] ) ) {
                            $atts[] = stripcslashes( $m[7] );
                        } elseif ( isset( $m[8] ) && strlen( $m[8] ) ) {
                            $atts[] = stripcslashes( $m[8] );
                        } elseif ( isset( $m[9] ) ) {
                            $atts[] = stripcslashes( $m[9] );
                        }
                    }

                    // Reject any unclosed HTML elements.
                    foreach ( $atts as &$value ) {
                        if ( false !== strpos( $value, '<' ) ) {
                            if ( 1 !== preg_match( '/^[^<]*+(?:<[^>]*+>[^<]*+)*+$/', $value ) ) {
                                $value = '';
                            }
                        }
                    }
                } else {
                    $atts = ltrim( $text );
                }

                $temp = $atts;

                $params = array();
                foreach ($temp as $key => $d){
                    $params[$key] = trim($d, '"');
                }
                $content = str_replace($actual_string[$i], $function($params), $content);
                $i++;
            }
        }
    }`