JezK

Edit File: ao-minify-html.php

<?php
/**
 * Class Minify_HTML
 * @package Minify
 */

/**
 * Compress HTML
 *
 * This is a heavy regex-based removal of whitespace, unnecessary comments and
 * tokens. IE conditional comments are preserved. There are also options to have
 * STYLE and SCRIPT blocks compressed by callback functions.
 *
 * A test suite is available.
 *
 * @package Minify
 * @author Stephen Clay <steve@mrclay.org>
 */
class AO_Minify_HTML {

/** @var string */
    private $_html;

/**
     * "Minify" an HTML page
     *
     * @param string $html
     *
     * @param array $options
     *
     * 'cssMinifier' : (optional) callback function to process content of STYLE
     * elements.
     *
     * 'jsMinifier' : (optional) callback function to process content of SCRIPT
     * elements. Note: the type attribute is ignored.
     *
     * 'xhtml' : (optional boolean) should content be treated as XHTML1.0? If
     * unset, minify will sniff for an XHTML doctype.
     *
     * 'keepComments' : (optional boolean) should the HTML comments be kept
     * in the HTML Code?
     *
     * @return string
     */
    public static function minify($html, $options = array()) {
        $min = new AO_Minify_HTML($html, $options);
        return $min->process();
    }

/**
     * Create a minifier object
     *
     * @param string $html
     *
     * @param array $options
     *
     * 'cssMinifier' : (optional) callback function to process content of STYLE
     * elements.
     *
     * 'jsMinifier' : (optional) callback function to process content of SCRIPT
     * elements. Note: the type attribute is ignored.
     *
     * 'xhtml' : (optional boolean) should content be treated as XHTML1.0? If
     * unset, minify will sniff for an XHTML doctype.
     *
     * 'xhtml' : (optional boolean) should content be treated as XHTML1.0? If
     * unset, minify will sniff for an XHTML doctype.
     *
     * @return null
     */
    public function __construct($html, $options = array())
    {
        $this->_html = str_replace("\r\n", "\n", trim($html));
        if (isset($options['xhtml'])) {
            $this->_isXhtml = (bool)$options['xhtml'];
        }
        if (isset($options['cssMinifier'])) {
            $this->_cssMinifier = $options['cssMinifier'];
        }
        if (isset($options['jsMinifier'])) {
            $this->_jsMinifier = $options['jsMinifier'];
        }
        if (isset($options['keepComments'])) {
            $this->_keepComments = $options['keepComments'];
        }
    }

/**
     * Minify the markeup given in the constructor
     *
     * @return string
     */
    public function process()
    {
        if ($this->_isXhtml === null) {
            $this->_isXhtml = (false !== strpos($this->_html, '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML'));
        }

$this->_replacementHash = 'MINIFYHTML' . bin2hex( random_bytes( 16 ) );
        $this->_placeholders = array();

// replace SCRIPTs (and minify) with placeholders
        $this->_html = preg_replace_callback(
            '/(\\s*)(<script\\b[^>]*?>)([\\s\\S]*?)<\\/script>(\\s*)/i'
            ,array($this, '_removeScriptCB')
            ,$this->_html);

// replace STYLEs (and minify) with placeholders
        $this->_html = preg_replace_callback(
            '/\\s*(<style\\b[^>]*?>)([\\s\\S]*?)<\\/style>\\s*/i'
            ,array($this, '_removeStyleCB')
            ,$this->_html);

// remove HTML comments (not containing IE conditional comments).
        if  ($this->_keepComments == false) {
            $this->_html = preg_replace_callback(
                '//'
                ,array($this, '_commentCB')
                ,$this->_html);
        }

// replace PREs with placeholders
        $this->_html = preg_replace_callback('/\\s*(<pre\\b[^>]*?>[\\s\\S]*?<\\/pre>)\\s*/i'
            ,array($this, '_removePreCB')
            ,$this->_html);

// replace TEXTAREAs with placeholders
        $this->_html = preg_replace_callback(
            '/\\s*(<textarea\\b[^>]*?>[\\s\\S]*?<\\/textarea>)\\s*/i'
            ,array($this, '_removeTextareaCB')
            ,$this->_html);

// replace data: URIs with placeholders
        $this->_html = preg_replace_callback(
            '/(=("|\')data:.*\\2)/Ui'
            ,array($this, '_removeDataURICB')
            ,$this->_html);

// trim each line.
        // replace by space instead of '' to avoid newline after opening tag getting zapped
        $this->_html = preg_replace('/^\s+|\s+$/m', ' ', $this->_html);

// remove ws around block/undisplayed elements
        $this->_html = preg_replace('/\\s+(<\\/?(?:area|article|aside|base(?:font)?|blockquote|body'
            .'|canvas|caption|center|col(?:group)?|dd|dir|div|dl|dt|fieldset|figcaption|figure|footer|form'
            .'|frame(?:set)?|h[1-6]|head|header|hgroup|hr|html|legend|li|link|main|map|menu|meta|nav'
            .'|ol|opt(?:group|ion)|output|p|param|section|t(?:able|body|head|d|h||r|foot|itle)'
            .'|ul|video)\\b[^>]*>)/i', '$1', $this->_html);

// remove ws outside of all elements
        $this->_html = preg_replace_callback(
            '/>([^<]+)</'
            ,array($this, '_outsideTagCB')
            ,$this->_html);

// use newlines before 1st attribute in open tags (to limit line lengths)
        //$this->_html = preg_replace('/(<[a-z\\-]+)\\s+([^>]+>)/i', "$1\n$2", $this->_html);

// reverse order while preserving keys to ensure the last replacement is done first, etc ...
        $this->_placeholders = array_reverse( $this->_placeholders, true );

// fill placeholders
        $this->_html = str_replace(
            array_keys($this->_placeholders)
            ,array_values($this->_placeholders)
            ,$this->_html
        );
        return $this->_html;
    }

protected function _commentCB($m)
    {
        return (0 === strpos($m[1], '[') || false !== strpos($m[1], '<!['))
            ? $m[0]
            : '';
    }

protected function _reservePlace($content)
    {
        $placeholder = '%' . $this->_replacementHash . count($this->_placeholders) . '%';
        $this->_placeholders[$placeholder] = $content;
        return $placeholder;
    }

protected $_isXhtml = null;
    protected $_replacementHash = null;
    protected $_placeholders = array();
    protected $_cssMinifier = null;
    protected $_jsMinifier = null;
    protected $_keepComments = false;

protected function _outsideTagCB($m)
    {
        return '>' . preg_replace('/^\\s+|\\s+$/', ' ', $m[1]) . '<';
    }

protected function _removePreCB($m)
    {
        return $this->_reservePlace($m[1]);
    }

protected function _removeTextareaCB($m)
    {
        return $this->_reservePlace($m[1]);
    }

protected function _removeDataURICB($m)
    {
        return $this->_reservePlace($m[1]);
    }

protected function _removeStyleCB($m)
    {
        $openStyle = $m[1];
        $css = $m[2];
        // remove HTML comments
        $css = preg_replace('/(?:^\\s*\\s*$)/', '', $css);

// remove CDATA section markers
        $css = $this->_removeCdata($css);

// minify
        $minifier = $this->_cssMinifier
            ? $this->_cssMinifier
            : 'trim';
        $css = call_user_func($minifier, $css);

return $this->_reservePlace($this->_needsCdata($css)
            ? "{$openStyle}/*<![CDATA[*/{$css}/*]]>*/</style>"
            : "{$openStyle}{$css}</style>"
        );
    }

protected function _removeScriptCB($m)
    {
        $openScript = $m[2];
        $js = $m[3];

// whitespace surrounding? preserve at least one space
        $ws1 = ($m[1] === '') ? '' : ' ';
        $ws2 = ($m[4] === '') ? '' : ' ';

if ($this->_keepComments == false) {
            // remove HTML comments (and ending "//" if present)
            $js = preg_replace('/(?:^\\s*\\s*$)/', '', $js);

// remove CDATA section markers
            $js = $this->_removeCdata($js);
        }

// minify
        $minifier = $this->_jsMinifier
            ? $this->_jsMinifier
            : 'trim';
        $js = call_user_func($minifier, $js);

return $this->_reservePlace($this->_needsCdata($js)
            ? "{$ws1}{$openScript}/*<![CDATA[*/{$js}/*]]>*/</script>{$ws2}"
            : "{$ws1}{$openScript}{$js}</script>{$ws2}"
        );
    }

protected function _removeCdata($str)
    {
        return (false !== strpos($str, '<![CDATA['))
            ? str_replace(array('/* <![CDATA[ */','/* ]]> */','/*<![CDATA[*/','/*]]>*/','<![CDATA[', ']]>'), '', $str)
            : $str;
    }

protected function _needsCdata($str)
    {
        return ($this->_isXhtml && preg_match('/(?:[<&]|\\-\\-|\\]\\]>)/', $str));
    }
}