isAllowedTag($tag) && !$this->isPixelTracker($tag, $attributes);
}
/**
* Return the HTML opening tag.
*
* @param string $tag Tag name
* @param string $attributes Attributes converted in html
*
* @return string
*/
public function openHtmlTag($tag, $attributes = '')
{
return '<'.$tag.(empty($attributes) ? '' : ' '.$attributes).($this->isSelfClosingTag($tag) ? '/>' : '>');
}
/**
* Return the HTML closing tag.
*
* @param string $tag Tag name
*
* @return string
*/
public function closeHtmlTag($tag)
{
return $this->isSelfClosingTag($tag) ? '' : '';
}
/**
* Return true is the tag is self-closing.
*
* @param string $tag Tag name
*
* @return bool
*/
public function isSelfClosingTag($tag)
{
return $tag === 'br' || $tag === 'img';
}
/**
* Check if a tag is on the whitelist.
*
* @param string $tag Tag name
*
* @return bool
*/
public function isAllowedTag($tag)
{
return in_array($tag, array_merge(
$this->tag_whitelist,
array_keys($this->config->getFilterWhitelistedTags(array()))
));
}
/**
* Detect if an image tag is a pixel tracker.
*
* @param string $tag Tag name
* @param array $attributes Tag attributes
*
* @return bool
*/
public function isPixelTracker($tag, array $attributes)
{
return $tag === 'img' &&
isset($attributes['height']) && isset($attributes['width']) &&
$attributes['height'] == 1 && $attributes['width'] == 1;
}
/**
* Remove script tags.
*
* @param string $data Input data
*
* @return string
*/
public function removeBlacklistedTags($data)
{
$dom = XmlParser::getDomDocument($data);
if ($dom === false) {
return '';
}
$xpath = new DOMXpath($dom);
$nodes = $xpath->query(implode(' | ', $this->tag_blacklist));
foreach ($nodes as $node) {
$node->parentNode->removeChild($node);
}
return $dom->saveXML();
}
/**
* Remove empty tags.
*
* @param string $data Input data
*
* @return string
*/
public function removeEmptyTags($data)
{
return preg_replace('/<([^<\/>]*)>([\s]*?|(?R))<\/\1>/imsU', '', $data);
}
/**
* Replace
by only one.
*
* @param string $data Input data
*
* @return string
*/
public function removeMultipleBreakTags($data)
{
return preg_replace("/(\s*)+/", '
', $data);
}
/**
* Set whitelisted tags adn attributes for each tag.
*
* @param array $values List of tags: ['video' => ['src', 'cover'], 'img' => ['src']]
*
* @return Tag
*/
public function setWhitelistedTags(array $values)
{
$this->tag_whitelist = $values ?: $this->tag_whitelist;
return $this;
}
}