src/Ease/Shared.php
public static function linkify($value, $protocols = array('http', 'mail'),
                                   array $attributes = array())
    {
        // Link attributes
        $attr = '';
        foreach ($attributes as $key => $val) {
            $attr = ' '.$key.'="'.htmlentities($val).'"';
        }

        $links = array();

        // Extract existing links and tags
        $value = preg_replace_callback('~(<a .*?>.*?</a>|<.*?>)~i',
            function ($match) use (&$links) {
            return '<'.array_push($links, $match[1]).'>';
        }, $value);

        // Extract text links for each protocol
        foreach ((array) $protocols as $protocol) {
            switch ($protocol) {
                case 'http':
                case 'https': $value = preg_replace_callback('~(?:(https?)://([^\s<]+)|(www\.[^\s<]+?\.[^\s<]+))(?<![\.,:])~i',
                        function ($match) use ($protocol, &$links, $attr) {
                        if ($match[1]) $protocol = $match[1];
                        $link     = $match[2] ?: $match[3];
                        return '<'.array_push($links,
                                "<a $attr href=\"$protocol://$link\">$link</a>").'>';
                    }, $value);
                    break;
                case 'mail': $value = preg_replace_callback('~([^\s<]+?@[^\s<]+?\.[^\s<]+)(?<![\.,:])~',
                        function ($match) use (&$links, $attr) {
                        return '<'.array_push($links,
                                "<a $attr href=\"mailto:{$match[1]}\">{$match[1]}</a>").'>';
                    }, $value);
                    break;
                case 'twitter': $value = preg_replace_callback('~(?<!\w)[@#](\w++)~',
                        function ($match) use (&$links, $attr) {
                        return '<'.array_push($links,
                                "<a $attr href=\"https://twitter.com/".($match[0][0]
                                == '@' ? '' : 'search/%23').$match[1]."\">{$match[0]}</a>").'>';
                    }, $value);
                    break;
                default: $value = preg_replace_callback('~'.preg_quote($protocol,
                            '~').'://([^\s<]+?)(?<![\.,:])~i',
                        function ($match) use ($protocol, &$links, $attr) {
                        return '<'.array_push($links,
                                "<a $attr href=\"$protocol://{$match[1]}\">{$match[1]}</a>").'>';
                    }, $value);
                    break;
            }
        }

        // Insert all link
        return preg_replace_callback('/<(\d+)>/',
            function ($match) use (&$links) {
            return $links[$match[1] - 1];
        }, $value);
    }
public static function linkify($value, $protocols = array('http', 'mail'),
                                   array $attributes = array())
    {
        // Link attributes
        $attr = '';
        foreach ($attributes as $key => $val) {
            $attr = ' '.$key.'="'.htmlentities($val).'"';
        }

        $links = array();

        // Extract existing links and tags
        $value = preg_replace_callback('~(<a .*?>.*?</a>|<.*?>)~i',
            function ($match) use (&$links) {
            return '<'.array_push($links, $match[1]).'>';
        }, $value);

        // Extract text links for each protocol
        foreach ((array) $protocols as $protocol) {
            switch ($protocol) {
                case 'http':
                case 'https': $value = preg_replace_callback('~(?:(https?)://([^\s<]+)|(www\.[^\s<]+?\.[^\s<]+))(?<![\.,:])~i',
                        function ($match) use ($protocol, &$links, $attr) {
                        if ($match[1]) $protocol = $match[1];
                        $link     = $match[2] ?: $match[3];
                        return '<'.array_push($links,
                                "<a $attr href=\"$protocol://$link\">$link</a>").'>';
                    }, $value);
                    break;
                case 'mail': $value = preg_replace_callback('~([^\s<]+?@[^\s<]+?\.[^\s<]+)(?<![\.,:])~',
                        function ($match) use (&$links, $attr) {
                        return '<'.array_push($links,
                                "<a $attr href=\"mailto:{$match[1]}\">{$match[1]}</a>").'>';
                    }, $value);
                    break;
                case 'twitter': $value = preg_replace_callback('~(?<!\w)[@#](\w++)~',
                        function ($match) use (&$links, $attr) {
                        return '<'.array_push($links,
                                "<a $attr href=\"https://twitter.com/".($match[0][0]
                                == '@' ? '' : 'search/%23').$match[1]."\">{$match[0]}</a>").'>';
                    }, $value);
                    break;
                default: $value = preg_replace_callback('~'.preg_quote($protocol,
                            '~').'://([^\s<]+?)(?<![\.,:])~i',
                        function ($match) use ($protocol, &$links, $attr) {
                        return '<'.array_push($links,
                                "<a $attr href=\"$protocol://{$match[1]}\">{$match[1]}</a>").'>';
                    }, $value);
                    break;
            }
        }

        // Insert all link
        return preg_replace_callback('/<(\d+)>/',
            function ($match) use (&$links) {
            return $links[$match[1] - 1];
        }, $value);
    }
Turn all URLs in clickable links.

@author Arnold Daniels <arnold@jasny.net>

@param string $value
@param array  $protocols  http/https, ftp, mail, twitter
@param array  $attributes
@param string $mode       normal or all

@return string