<?php
/**
* @file
* Extendable Object Faces API. Provided by the faces module.
*/
if (!interface_exists('FacesExtenderInterface', FALSE)) {
/**
* Interface for extenders.
*/
interface FacesExtenderInterface {
/**
* Constructs an instance of the extender.
*/
public function __construct(FacesExtendable $object);
/**
* Returns the extended object.
*/
public function getExtendable();
}
/**
* The Exception thrown by the FacesExtendable.
*/
class FacesExtendableException extends ErrorException {}
}
if (!class_exists('FacesExtender', FALSE)) {
/**
* A common base class for FacesExtenders.
*
* Extenders may access protected methods and properties of the extendable
* using the property() and call() methods.
*/
abstract class FacesExtender implements FacesExtenderInterface {
/**
* @var FacesExtendable
*/
protected $object;
public function __construct(FacesExtendable $object) {
$this->object = $object;
}
/**
* Returns the extended object.
*/
public function getExtendable() {
return $this->object;
}
/**
* Makes protected properties of the extendable accessible.
*/
protected function & property($name) {
$var =& $this->object->property($name);
return $var;
}
/**
* Invokes any method on the extended object, including protected methods.
*
* @param string $name
* The method name.
* @param array $args
* An array of arguments to pass to the method.
*/
protected function call($name, array $args = array()) {
return $this->object->call($name, $args);
}
}
}
if (!class_exists('FacesExtendable', FALSE)) {
/**
* An extendable base class.
*/
abstract class FacesExtendable {
protected $facesMethods = array();
protected $faces = array();
protected $facesIncludes = array();
protected $facesClassInstances = array();
static protected $facesIncluded = array();
/**
* Wraps calls to module_load_include() to prevent multiple inclusions.
*
* @see module_load_include()
*/
protected static function load_include($args) {
$args += array('type' => 'inc', 'module' => '', 'name' => NULL);
$key = implode(':', $args);
if (!isset(self::$facesIncluded[$key])) {
self::$facesIncluded[$key] = TRUE;
module_load_include($args['type'], $args['module'], $args['name']);
}
}
/**
* Magic method: Invoke the dynamically implemented methods.
*/
public function __call($name, $arguments = array()) {
if (isset($this->facesMethods[$name])) {
$method = $this->facesMethods[$name];
// Include code, if necessary.
if (isset($this->facesIncludes[$name])) {
self::load_include($this->facesIncludes[$name]);
$this->facesIncludes[$name] = NULL;
}
if (isset($method[0])) {
// We always pass the object reference and the name of the method.
$arguments[] = $this;
$arguments[] = $name;
return call_user_func_array($method[0], $arguments);
}
// Call the method on the extender object, but don't use extender()
// for performance reasons.
if (!isset($this->facesClassInstances[$method[1]])) {
$this->facesClassInstances[$method[1]] = new $method[1]($this);
}
return call_user_func_array(array($this->facesClassInstances[$method[1]], $name), $arguments);
}
$class = check_plain(get_class($this));
throw new FacesExtendableException("There is no method $name for this instance of the class $class.");
}
/**
* Returns the extender object for the given class.
*
* May be used to explicitly invoke a specific extender, e.g. a function
* overriding a method may use that to explicitly invoke the original
* extender.
*/
public function extender($class) {
if (!isset($this->facesClassInstances[$class])) {
$this->facesClassInstances[$class] = new $class($this);
}
return $this->facesClassInstances[$class];
}
/**
* Returns whether the object can face as the given interface.
*
* Returns whether the object can face as the given interface, thus it
* returns TRUE if this object has been extended by an appropriate
* implementation.
*
* @param $interface
* (optional) An interface to test for. If it's omitted, all interfaces
* that the object can be faced as are returned.
*
* @return bool
* Whether the object can face as the interface or an array of interface
* names.
*/
public function facesAs($interface = NULL) {
if (!isset($interface)) {
return array_values($this->faces);
}
return in_array($interface, $this->faces) || $this instanceof $interface;
}
/**
* Extend the object by a class to implement the given interfaces.
*
* @param $interface
* The interface name or an array of interface names.
* @param $className
* The extender class, which has to implement the FacesExtenderInterface.
* @param array $includes
* An optional array describing the file to include before invoking the
* class. The array entries known are 'type', 'module', and 'name'
* matching the parameters of module_load_include(). Only 'module' is
* required as 'type' defaults to 'inc' and 'name' to NULL.
*/
public function extendByClass($interface, $className, array $includes = array()) {
$parents = class_implements($className);
if (!in_array('FacesExtenderInterface', $parents)) {
throw new FacesExtendableException("The class " . check_plain($className) . " doesn't implement the FacesExtenderInterface.");
}
$interfaces = is_array($interface) ? $interface : array($interface);
foreach ($interfaces as $interface) {
if (!in_array($interface, $parents)) {
throw new FacesExtendableException("The class " . check_plain($className) . " doesn't implement the interface " . check_plain($interface) . ".");
}
$this->faces[$interface] = $interface;
$this->faces += class_implements($interface);
$face_methods = get_class_methods($interface);
$this->addIncludes($face_methods, $includes);
foreach ($face_methods as $method) {
$this->facesMethods[$method] = array(1 => $className);
}
}
}
/**
* Extend the object by the given functions to implement the given
* interface. There has to be an implementation function for each method of
* the interface.
*
* @param $interface
* The interface name or FALSE to extend the object without a given
* interface.
* @param array $callbacks
* An array, where the keys are methods of the given interface and the
* values the callback functions to use.
* @param array $includes
* An optional array to describe files to include before invoking the
* callbacks. You may pass a single array describing one include for all
* callbacks or an array of arrays, keyed by the method names. Look at the
* extendByClass() $include parameter for more details about how to
* describe a single file.
*/
public function extend($interface, array $callbacks = array(), array $includes = array()) {
//UPEI added line below
$interface = class_exists($interface) ? $interface : FALSE;
$face_methods = $interface ? get_class_methods($interface) : array_keys($callbacks);
if ($interface) {
if (array_diff($face_methods, array_keys($callbacks))) {
throw new FacesExtendableException("Missing methods for implementing the interface " . check_plain($interface) . ".");
}
$this->faces[$interface] = $interface;
$this->faces += class_implements($interface);
}
$this->addIncludes($face_methods, $includes);
foreach ($face_methods as $method) {
$this->facesMethods[$method] = array(0 => $callbacks[$method]);
}
}
/**
* Override the implementation of an extended method.
*
* @param array $callbacks
* An array of methods of the interface, that should be overridden, where
* the keys are methods to override and the values the callback functions
* to use.
* @param array $includes
* An optional array to describe files to include before invoking the
* callbacks. You may pass a single array describing one include for all
* callbacks or an array of arrays, keyed by the method names. Look at the
* extendByClass() $include parameter for more details about how to
* describe a single file.
*/
public function override(array $callbacks = array(), array $includes = array()) {
if (array_diff_key($callbacks, $this->facesMethods)) {
throw new FacesExtendableException("A not implemented method is to be overridden.");
}
$this->addIncludes(array_keys($callbacks), $includes);
foreach ($callbacks as $method => $callback) {
$this->facesMethods[$method] = array(0 => $callback);
}
}
/**
* Adds in include files for the given methods while removing any old files.
*
* If a single include file is described, it's added for all methods.
*/
protected function addIncludes($methods, $includes) {
$includes = isset($includes['module']) & & is_string($includes['module']) ? array_fill_keys($methods, $includes) : $includes;
$this->facesIncludes = $includes + array_diff_key($this->facesIncludes, array_flip($methods));
}
/**
* Only serialize what is really necessary.
*/
public function __sleep() {
return array('facesMethods', 'faces', 'facesIncludes');
}
/**
* Destroys all references to created instances.
*
* Destroys all references to created instances so that PHP's garbage
* collection can do its work. This is needed as PHP's gc has troubles with
* circular references until PHP < 5.3.
*/
public function destroy() {
// Avoid circular references.
$this->facesClassInstances = array();
}
/**
* Makes protected properties accessible.
*/
public function & property($name) {
if (property_exists($this, $name)) {
return $this->$name;
}
}
/**
* Invokes any method.
*
* This also allows to pass arguments by reference, so it may be used to
* pass arguments by reference to dynamically extended methods.
*
* @param string $name
* The method name.
* @param array $args
* An array of arguments to pass to the method.
*/
public function call($name, array $args = array()) {
if (method_exists($this, $name)) {
return call_user_func_array(array($this, $name), $args);
}
return $this->__call($name, $args);
}
}
}
