Developer
<?php
/**
* Microsoft's proprietary filter: CSS property
* @note Currently supports the alpha filter. In the future, this will
* probably need an extensible framework
*/
class HTMLPurifier_AttrDef_CSS_Filter extends HTMLPurifier_AttrDef
{
/**
* @type HTMLPurifier_AttrDef_Integer
*/
protected $intValidator;
public function __construct()
{
$this->intValidator = new HTMLPurifier_AttrDef_Integer();
}
/**
* @param string $value
* @param HTMLPurifier_Config $config
* @param HTMLPurifier_Context $context
* @return bool|string
*/
public function validate($value, $config, $context)
{
$value = $this->parseCDATA($value);
if ($value === 'none') {
return $value;
}
// if we looped this we could support multiple filters
$function_length = strcspn($value, '(');
$function = trim(substr($value, 0, $function_length));
if ($function !== 'alpha' &&
$function !== 'Alpha' &&
$function !== 'progid:DXImageTransform.Microsoft.Alpha'
) {
return false;
}
$cursor = $function_length + 1;
$parameters_length = strcspn($value, ')', $cursor);
$parameters = substr($value, $cursor, $parameters_length);
$params = explode(',', $parameters);
$ret_params = array();
$lookup = array();
foreach ($params as $param) {
list($key, $value) = explode('=', $param);
$key = trim($key);
$value = trim($value);
if (isset($lookup[$key])) {
continue;
}
if ($key !== 'opacity') {
continue;
}
$value = $this->intValidator->validate($value, $config, $context);
if ($value === false) {
continue;
}
$int = (int)$value;
if ($int > 100) {
$value = '100';
}
if ($int < 0) {
$value = '0';
}
$ret_params[] = "$key=$value";
$lookup[$key] = true;
}
$ret_parameters = implode(',', $ret_params);
$ret_function = "$function($ret_parameters)";
return $ret_function;
}
}
// vim: et sw=4 sts=4
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