<?php
/**
* Validates a color according to the HTML spec.
*/
class HTMLPurifier_AttrDef_HTML_Color extends HTMLPurifier_AttrDef
{
/**
* @param string $string
* @param HTMLPurifier_Config $config
* @param HTMLPurifier_Context $context
* @return bool|string
*/
public function validate($string, $config, $context)
{
static $colors = null;
if ($colors === null) {
$colors = $config->get('Core.ColorKeywords');
}
$string = trim($string);
if (empty($string)) {
return false;
}
$lower = strtolower($string);
if (isset($colors[$lower])) {
return $colors[$lower];
}
if ($string[0] === '#') {
$hex = substr($string, 1);
} else {
$hex = $string;
}
$length = strlen($hex);
if ($length !== 3 && $length !== 6) {
return false;
}
if (!ctype_xdigit($hex)) {
return false;
}
if ($length === 3) {
$hex = $hex[0] . $hex[0] . $hex[1] . $hex[1] . $hex[2] . $hex[2];
}
return "#$hex";
}
}
// vim: et sw=4 sts=4