<?php
/**
* Represents an individual tag within an HTML tree.
*
* @package XenForo_Html
*/
class XenForo_Html_Tag
{
/**
* Name of the tag (lower case).
*
* @var string
*/
protected $_tagName = '';
/**
* Key-value pairs of attributes for the tag
*
* @var array
*/
protected $_attributes = array();
/**
* Parent tag object.
*
* @var XenForo_Html_Tag|null Null for root tag
*/
protected $_parent = null;
/**
* List of child tags and text.
*
* @var array Values are XenForo_Html_Tag or XenForo_Html_Text elements
*/
protected $_children = array();
/**
* List of tags that are considered to be block tags.
*
* @var array
*/
protected $_blockTags = array(
'address', 'article', 'aside', 'audio', 'blockquote',
'canvas', 'dd', 'div', 'dl', 'dt', 'fieldset', 'figcaption',
'figure', 'footer', 'form', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6',
'header', 'hgroup', 'hr', 'li', 'nav', 'ol', 'output', 'p', 'pre',
'section', 'table', 'tbody', 'tfoot', 'thead', 'tr', 'ul', 'video'
// note that "" is not here
);
protected $_voidTags = array(
'area', 'base', 'br', 'col', 'command', 'embed', 'hr', 'img', 'input', 'keygen', 'link', 'meta', 'param', 'source', 'wbr'
);
/**
* Constructor.
*
* @param string $tagName
* @param array $attributes
* @param XenForo_Html_Tag $parent
*/
public function __construct($tagName, array $attributes = array(), XenForo_Html_Tag $parent = null)
{
$this->_tagName = strtolower($tagName);
$this->_attributes = $attributes;
$this->_parent = $parent;
}
/**
* Appends text to the tag. If the last child is text, it will be added
* to that child; otherwise, a new child will be created.
*
* @param string $text
*/
public function appendText($text)
{
if ($this->isVoid())
{
throw new XenForo_Exception('Void tag ' . htmlspecialchars($this->_tagName) . ' cannot have children');
}
if ($this->_children)
{
$keys = array_keys($this->_children);
$lastKey = end($keys);
if ($this->_children[$lastKey] instanceof XenForo_Html_Text)
{
$this->_children[$lastKey]->addText($text);
return;
}
}
$this->_children[] = new XenForo_Html_Text($text, $this);
}
/**
* Adds a new child tag.
*
* @param string $tagName
* @param array $attributes
*
* @return XenForo_Html_Tag New child tag
*/
public function addChildTag($tagName, array $attributes = array())
{
if ($this->isVoid())
{
throw new XenForo_Exception('Void tag ' . htmlspecialchars($this->_tagName) . ' cannot have children');
}
if (($tagName == 'li' || $tagName == 'p') && $tagName == $this->_tagName)
{
// can't child to this tag, should be a sibling
$parent = $this->parent();
if ($parent)
{
return $parent->addChildTag($tagName, $attributes);
}
}
$child = new XenForo_Html_Tag($tagName, $attributes, $this);
$this->_children[] = $child;
return $child;
}
/**
* Closes the given tag. This generally does not require modifying the tag tree,
* unless invalid nesting occurred.
*
* @param string $tagName
*
* @return XenForo_Html_Tag The new "parent" tag that should be used by the parser
*/
public function closeTag($tagName)
{
$tagName = strtolower($tagName);
if ($tagName == $this->_tagName || $this->isVoid())
{
return $this->_parent;
}
else
{
$stack = array();
for ($tag = $this; $tag && $tag->tagName() != $tagName; $tag = $tag->parent())
{
$stack[] = $tag;
}
if ($tag)
{
$newParent = $tag->closeTag($tagName);
while ($createTag = array_pop($stack))
{
$newParent = $newParent->addChildTag($createTag->tagName(), $createTag->attributes());
}
return $newParent;
}
else
{
// tag not found, ignore it
return $this->_parent;
}
}
}
/**
* Gets the tag name.
*
* @return string
*/
public function tagName()
{
return $this->_tagName;
}
/**
* Gets the attributes.
*
* @return array
*/
public function attributes()
{
return $this->_attributes;
}
/**
* Gets the named attribute.
*
* @param string $attribute
*
* @return mixed|false
*/
public function attribute($attribute)
{
return (isset($this->_attributes[$attribute]) ? $this->_attributes[$attribute] : false);
}
/**
* Gets the parent tag.
*
* @return XenForo_Html_Tag|null
*/
public function parent()
{
return $this->_parent;
}
/**
* Sets the parent tag. This does not check for circular references!
*
* @param XenForo_Html_Tag $parent
*/
public function setParent(XenForo_Html_Tag $parent)
{
$this->_parent = $parent;
}
/**
* Gets the child tags and text.
*
* @return array
*/
public function children()
{
return $this->_children;
}
/**
* Copies this tag. Does not copy any children tags or this tag's parent. The
* parent will need to be set manually later.
*
* @return XenForo_Html_Tag
*/
public function copy()
{
return new XenForo_Html_Tag($this->_tagName, $this->_attributes);
}
/**
* Determines if the tag has renderable content within.
*
* @return boolean
*/
public function isEmpty()
{
switch ($this->_tagName)
{
case 'img':
case 'br':
return false;
}
foreach ($this->children() AS $child)
{
if ($child instanceof XenForo_Html_Tag)
{
if (!$child->isEmpty())
{
return false;
}
}
else if ($child instanceof XenForo_Html_Text)
{
if (trim($child->text()) !== '')
{
return false;
}
}
}
return true;
}
/**
* Determines if this tag is a block-level tag.
*
* @return boolean
*/
public function isBlock()
{
return in_array($this->_tagName, $this->_blockTags);
}
/**
* Determines if this tag is a void tag. Void tags can't have children.
*
* @return boolean
*/
public function isVoid()
{
return in_array($this->_tagName, $this->_voidTags);
}
}