<?php
/**
* Structure that stores an HTML element definition. Used by
* HTMLPurifier_HTMLDefinition and HTMLPurifier_HTMLModule.
* @note This class is inspected by HTMLPurifier_Printer_HTMLDefinition.
* Please update that class too.
* @warning If you add new properties to this class, you MUST update
* the mergeIn() method.
*/
class HTMLPurifier_ElementDef
{
/**
* Does the definition work by itself, or is it created solely
* for the purpose of merging into another definition?
* @type bool
*/
public $standalone = true;
/**
* Associative array of attribute name to HTMLPurifier_AttrDef.
* @type array
* @note Before being processed by HTMLPurifier_AttrCollections
* when modules are finalized during
* HTMLPurifier_HTMLDefinition->setup(), this array may also
* contain an array at index 0 that indicates which attribute
* collections to load into the full array. It may also
* contain string indentifiers in lieu of HTMLPurifier_AttrDef,
* see HTMLPurifier_AttrTypes on how they are expanded during
* HTMLPurifier_HTMLDefinition->setup() processing.
*/
public $attr = array();
// XXX: Design note: currently, it's not possible to override
// previously defined AttrTransforms without messing around with
// the final generated config. This is by design; a previous version
// used an associated list of attr_transform, but it was extremely
// easy to accidentally override other attribute transforms by
// forgetting to specify an index (and just using 0.) While we
// could check this by checking the index number and complaining,
// there is a second problem which is that it is not at all easy to
// tell when something is getting overridden. Combine this with a
// codebase where this isn't really being used, and it's perfect for
// nuking.
/**
* List of tags HTMLPurifier_AttrTransform to be done before validation.
* @type array
*/
public $attr_transform_pre = array();
/**
* List of tags HTMLPurifier_AttrTransform to be done after validation.
* @type array
*/
public $attr_transform_post = array();
/**
* HTMLPurifier_ChildDef of this tag.
* @type HTMLPurifier_ChildDef
*/
public $child;
/**
* Abstract string representation of internal ChildDef rules.
* @see HTMLPurifier_ContentSets for how this is parsed and then transformed
* into an HTMLPurifier_ChildDef.
* @warning This is a temporary variable that is not available after
* being processed by HTMLDefinition
* @type string
*/
public $content_model;
/**
* Value of $child->type, used to determine which ChildDef to use,
* used in combination with $content_model.
* @warning This must be lowercase
* @warning This is a temporary variable that is not available after
* being processed by HTMLDefinition
* @type string
*/
public $content_model_type;
/**
* Does the element have a content model (#PCDATA | Inline)*? This
* is important for chameleon ins and del processing in
* HTMLPurifier_ChildDef_Chameleon. Dynamically set: modules don't
* have to worry about this one.
* @type bool
*/
public $descendants_are_inline = false;
/**
* List of the names of required attributes this element has.
* Dynamically populated by HTMLPurifier_HTMLDefinition::getElement()
* @type array
*/
public $required_attr = array();
/**
* Lookup table of tags excluded from all descendants of this tag.
* @type array
* @note SGML permits exclusions for all descendants, but this is
* not possible with DTDs or XML Schemas. W3C has elected to
* use complicated compositions of content_models to simulate
* exclusion for children, but we go the simpler, SGML-style
* route of flat-out exclusions, which correctly apply to
* all descendants and not just children. Note that the XHTML
* Modularization Abstract Modules are blithely unaware of such
* distinctions.
*/
public $excludes = array();
/**
* This tag is explicitly auto-closed by the following tags.
* @type array
*/
public $autoclose = array();
/**
* If a foreign element is found in this element, test if it is
* allowed by this sub-element; if it is, instead of closing the
* current element, place it inside this element.
* @type string
*/
public $wrap;
/**
* Whether or not this is a formatting element affected by the
* "Active Formatting Elements" algorithm.
* @type bool
*/
public $formatting;
/**
* Low-level factory constructor for creating new standalone element defs
*/
public static function create($content_model, $content_model_type, $attr)
{
$def = new HTMLPurifier_ElementDef();
$def->content_model = $content_model;
$def->content_model_type = $content_model_type;
$def->attr = $attr;
return $def;
}
/**
* Merges the values of another element definition into this one.
* Values from the new element def take precedence if a value is
* not mergeable.
* @param HTMLPurifier_ElementDef $def
*/
public function mergeIn($def)
{
// later keys takes precedence
foreach ($def->attr as $k => $v) {
if ($k === 0) {
// merge in the includes
// sorry, no way to override an include
foreach ($v as $v2) {
$this->attr[0][] = $v2;
}
continue;
}
if ($v === false) {
if (isset($this->attr[$k])) {
unset($this->attr[$k]);
}
continue;
}
$this->attr[$k] = $v;
}
$this->_mergeAssocArray($this->excludes, $def->excludes);
$this->attr_transform_pre = array_merge($this->attr_transform_pre, $def->attr_transform_pre);
$this->attr_transform_post = array_merge($this->attr_transform_post, $def->attr_transform_post);
if (!empty($def->content_model)) {
$this->content_model =
str_replace("#SUPER", $this->content_model, $def->content_model);
$this->child = false;
}
if (!empty($def->content_model_type)) {
$this->content_model_type = $def->content_model_type;
$this->child = false;
}
if (!is_null($def->child)) {
$this->child = $def->child;
}
if (!is_null($def->formatting)) {
$this->formatting = $def->formatting;
}
if ($def->descendants_are_inline) {
$this->descendants_are_inline = $def->descendants_are_inline;
}
}
/**
* Merges one array into another, removes values which equal false
* @param $a1 Array by reference that is merged into
* @param $a2 Array that merges into $a1
*/
private function _mergeAssocArray(&$a1, $a2)
{
foreach ($a2 as $k => $v) {
if ($v === false) {
if (isset($a1[$k])) {
unset($a1[$k]);
}
continue;
}
$a1[$k] = $v;
}
}
}
// vim: et sw=4 sts=4