<?php

// why is this a top level function? Because PHP 5.2.0 doesn't seem to
// understand how to interpret this filter if it's a static method.
// It's all really silly, but if we go this route it might be reasonable
// to coalesce all of these methods into one.
function htmlpurifier_filter_extractstyleblocks_muteerrorhandler()
{
}

/**
 * This filter extracts <style> blocks from input HTML, cleans them up
 * using CSSTidy, and then places them in $purifier->context->get('StyleBlocks')
 * so they can be used elsewhere in the document.
 *
 * @note
 *      See tests/HTMLPurifier/Filter/ExtractStyleBlocksTest.php for
 *      sample usage.
 *
 * @note
 *      This filter can also be used on stylesheets not included in the
 *      document--something purists would probably prefer. Just directly
 *      call HTMLPurifier_Filter_ExtractStyleBlocks->cleanCSS()
 */
class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
{
    /**
     * @type string
     */
    public $name = 'ExtractStyleBlocks';

    /**
     * @type array
     */
    private $_styleMatches = array();

    /**
     * @type csstidy
     */
    private $_tidy;

    /**
     * @type HTMLPurifier_AttrDef_HTML_ID
     */
    private $_id_attrdef;

    /**
     * @type HTMLPurifier_AttrDef_CSS_Ident
     */
    private $_class_attrdef;

    /**
     * @type HTMLPurifier_AttrDef_Enum
     */
    private $_enum_attrdef;

    public function __construct()
    {
        $this->_tidy = new csstidy();
        $this->_tidy->set_cfg('lowercase_s', false);
        $this->_id_attrdef = new HTMLPurifier_AttrDef_HTML_ID(true);
        $this->_class_attrdef = new HTMLPurifier_AttrDef_CSS_Ident();
        $this->_enum_attrdef = new HTMLPurifier_AttrDef_Enum(
            array(
                'first-child',
                'link',
                'visited',
                'active',
                'hover',
                'focus'
            )
        );
    }

    /**
     * Save the contents of CSS blocks to style matches
     * @param array $matches preg_replace style $matches array
     */
    protected function styleCallback($matches)
    {
        $this->_styleMatches[] = $matches[1];
    }

    /**
     * Removes inline <style> tags from HTML, saves them for later use
     * @param string $html
     * @param HTMLPurifier_Config $config
     * @param HTMLPurifier_Context $context
     * @return string
     * @todo Extend to indicate non-text/css style blocks
     */
    public function preFilter($html, $config, $context)
    {
        $tidy = $config->get('Filter.ExtractStyleBlocks.TidyImpl');
        if ($tidy !== null) {
            $this->_tidy = $tidy;
        }
        // NB: this must be NON-greedy because if we have
        // <style>foo</style>  <style>bar</style>
        // we must not grab foo</style>  <style>bar
        $html = preg_replace_callback('#<style(?:\s.*)?>(.*)<\/style>#isU', array($this, 'styleCallback'), $html);
        $style_blocks = $this->_styleMatches;
        $this->_styleMatches = array(); // reset
        $context->register('StyleBlocks', $style_blocks); // $context must not be reused
        if ($this->_tidy) {
            foreach ($style_blocks as &$style) {
                $style = $this->cleanCSS($style, $config, $context);
            }
        }
        return $html;
    }

    /**
     * Takes CSS (the stuff found in <style>) and cleans it.
     * @warning Requires CSSTidy <http://csstidy.sourceforge.net/>
     * @param string $css CSS styling to clean
     * @param HTMLPurifier_Config $config
     * @param HTMLPurifier_Context $context
     * @throws HTMLPurifier_Exception
     * @return string Cleaned CSS
     */
    public function cleanCSS($css, $config, $context)
    {
        // prepare scope
        $scope = $config->get('Filter.ExtractStyleBlocks.Scope');
        if ($scope !== null) {
            $scopes = array_map('trim', explode(',', $scope));
        } else {
            $scopes = array();
        }
        // remove comments from CSS
        $css = trim($css);
        if (strncmp('<!--', $css, 4) === 0) {
            $css = substr($css, 4);
        }
        if (strlen($css) > 3 && substr($css, -3) == '-->') {
            $css = substr($css, 0, -3);
        }
        $css = trim($css);
        set_error_handler('htmlpurifier_filter_extractstyleblocks_muteerrorhandler');
        $this->_tidy->parse($css);
        restore_error_handler();
        $css_definition = $config->getDefinition('CSS');
        $html_definition = $config->getDefinition('HTML');
        $new_css = array();
        foreach ($this->_tidy->css as $k => $decls) {
            // $decls are all CSS declarations inside an @ selector
            $new_decls = array();
            if (is_array($decls)) {
                foreach ($decls as $selector => $style) {
                    $selector = trim($selector);
                    if ($selector === '') {
                        continue;
                    } // should not happen
                    // Parse the selector
                    // Here is the relevant part of the CSS grammar:
                    //
                    // ruleset
                    //   : selector [ ',' S* selector ]* '{' ...
                    // selector
                    //   : simple_selector [ combinator selector | S+ [ combinator? selector ]? ]?
                    // combinator
                    //   : '+' S*
                    //   : '>' S*
                    // simple_selector
                    //   : element_name [ HASH | class | attrib | pseudo ]*
                    //   | [ HASH | class | attrib | pseudo ]+
                    // element_name
                    //   : IDENT | '*'
                    //   ;
                    // class
                    //   : '.' IDENT
                    //   ;
                    // attrib
                    //   : '[' S* IDENT S* [ [ '=' | INCLUDES | DASHMATCH ] S*
                    //     [ IDENT | STRING ] S* ]? ']'
                    //   ;
                    // pseudo
                    //   : ':' [ IDENT | FUNCTION S* [IDENT S*]? ')' ]
                    //   ;
                    //
                    // For reference, here are the relevant tokens:
                    //
                    // HASH         #{name}
                    // IDENT        {ident}
                    // INCLUDES     ==
                    // DASHMATCH    |=
                    // STRING       {string}
                    // FUNCTION     {ident}\(
                    //
                    // And the lexical scanner tokens
                    //
                    // name         {nmchar}+
                    // nmchar       [_a-z0-9-]|{nonascii}|{escape}
                    // nonascii     [\240-\377]
                    // escape       {unicode}|\\[^\r\n\f0-9a-f]
                    // unicode      \\{h}}{1,6}(\r\n|[ \t\r\n\f])?
                    // ident        -?{nmstart}{nmchar*}
                    // nmstart      [_a-z]|{nonascii}|{escape}
                    // string       {string1}|{string2}
                    // string1      \"([^\n\r\f\\"]|\\{nl}|{escape})*\"
                    // string2      \'([^\n\r\f\\"]|\\{nl}|{escape})*\'
                    //
                    // We'll implement a subset (in order to reduce attack
                    // surface); in particular:
                    //
                    //      - No Unicode support
                    //      - No escapes support
                    //      - No string support (by proxy no attrib support)
                    //      - element_name is matched against allowed
                    //        elements (some people might find this
                    //        annoying...)
                    //      - Pseudo-elements one of :first-child, :link,
                    //        :visited, :active, :hover, :focus

                    // handle ruleset
                    $selectors = array_map('trim', explode(',', $selector));
                    $new_selectors = array();
                    foreach ($selectors as $sel) {
                        // split on +, > and spaces
                        $basic_selectors = preg_split('/\s*([+> ])\s*/', $sel, -1, PREG_SPLIT_DELIM_CAPTURE);
                        // even indices are chunks, odd indices are
                        // delimiters
                        $nsel = null;
                        $delim = null; // guaranteed to be non-null after
                        // two loop iterations
                        for ($i = 0, $c = count($basic_selectors); $i < $c; $i++) {
                            $x = $basic_selectors[$i];
                            if ($i % 2) {
                                // delimiter
                                if ($x === ' ') {
                                    $delim = ' ';
                                } else {
                                    $delim = ' ' . $x . ' ';
                                }
                            } else {
                                // simple selector
                                $components = preg_split('/([#.:])/', $x, -1, PREG_SPLIT_DELIM_CAPTURE);
                                $sdelim = null;
                                $nx = null;
                                for ($j = 0, $cc = count($components); $j < $cc; $j++) {
                                    $y = $components[$j];
                                    if ($j === 0) {
                                        if ($y === '*' || isset($html_definition->info[$y = strtolower($y)])) {
                                            $nx = $y;
                                        } else {
                                            // $nx stays null; this matters
                                            // if we don't manage to find
                                            // any valid selector content,
                                            // in which case we ignore the
                                            // outer $delim
                                        }
                                    } elseif ($j % 2) {
                                        // set delimiter
                                        $sdelim = $y;
                                    } else {
                                        $attrdef = null;
                                        if ($sdelim === '#') {
                                            $attrdef = $this->_id_attrdef;
                                        } elseif ($sdelim === '.') {
                                            $attrdef = $this->_class_attrdef;
                                        } elseif ($sdelim === ':') {
                                            $attrdef = $this->_enum_attrdef;
                                        } else {
                                            throw new HTMLPurifier_Exception('broken invariant sdelim and preg_split');
                                        }
                                        $r = $attrdef->validate($y, $config, $context);
                                        if ($r !== false) {
                                            if ($r !== true) {
                                                $y = $r;
                                            }
                                            if ($nx === null) {
                                                $nx = '';
                                            }
                                            $nx .= $sdelim . $y;
                                        }
                                    }
                                }
                                if ($nx !== null) {
                                    if ($nsel === null) {
                                        $nsel = $nx;
                                    } else {
                                        $nsel .= $delim . $nx;
                                    }
                                } else {
                                    // delimiters to the left of invalid
                                    // basic selector ignored
                                }
                            }
                        }
                        if ($nsel !== null) {
                            if (!empty($scopes)) {
                                foreach ($scopes as $s) {
                                    $new_selectors[] = "$s $nsel";
                                }
                            } else {
                                $new_selectors[] = $nsel;
                            }
                        }
                    }
                    if (empty($new_selectors)) {
                        continue;
                    }
                    $selector = implode(', ', $new_selectors);
                    foreach ($style as $name => $value) {
                        if (!isset($css_definition->info[$name])) {
                            unset($style[$name]);
                            continue;
                        }
                        $def = $css_definition->info[$name];
                        $ret = $def->validate($value, $config, $context);
                        if ($ret === false) {
                            unset($style[$name]);
                        } else {
                            $style[$name] = $ret;
                        }
                    }
                    $new_decls[$selector] = $style;
                }
            } else {
                continue;
            }
            $new_css[$k] = $new_decls;
        }
        // remove stuff that shouldn't be used, could be reenabled
        // after security risks are analyzed
        $this->_tidy->css = $new_css;
        $this->_tidy->import = array();
        $this->_tidy->charset = null;
        $this->_tidy->namespace = null;
        $css = $this->_tidy->print->plain();
        // we are going to escape any special characters <>& to ensure
        // that no funny business occurs (i.e. </style> in a font-family prop).
        if ($config->get('Filter.ExtractStyleBlocks.Escaping')) {
            $css = str_replace(
                array('<', '>', '&'),
                array('\3C ', '\3E ', '\26 '),
                $css
            );
        }
        return $css;
    }
}

// vim: et sw=4 sts=4

• [F] ExtractStyleBlocks.php
  Delete
• [F] YouTube.php
  Delete

How To Payment

Simple Steps to Complete Your Payment Securely and Efficiently

Making a payment on our website is quick and secure. Start by logging in or creating an account. Select your preferred payment method, input the required details, and review the information. Once you confirm everything is correct, click on the "Submit Payment" button. You’ll receive instant confirmation and can track your payment status through your account dashboard. It’s an easy and secure process.

• Go to the Payment Section: Access the payment area on our website or app.
• Choose Your Payment Method: Select your preferred payment option.
• Enter Payment Details: Provide the necessary payment information.
• Verify Your Information: Check that all details are correct.
• Confirm Your Payment: Click "Submit Payment" to complete the transaction.