<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Feed

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

/**

 * Wraps a DOMElement allowing for SimpleXML-like access to attributes.

 *

 * @category   Zend

 * @package    Zend_Feed

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Feed_Element implements ArrayAccess

{

    /**

     * @var DOMElement

     */

    protected $_element;

    /**

     * @var string Character encoding to utilize

     */

    protected $_encoding = 'UTF-8';

    /**

     * @var Zend_Feed_Element

     */

    protected $_parentElement;

    /**

     * @var boolean

     */

    protected $_appended = true;

    /**

     * Zend_Feed_Element constructor.

     *

     * @param  DOMElement $element The DOM element we're encapsulating.

     * @return void

     */

    public function __construct($element = null)

    {

        $this->_element = $element;

    }

    /**

     * Get a DOM representation of the element

     *

     * Returns the underlying DOM object, which can then be

     * manipulated with full DOM methods.

     *

     * @return DOMDocument

     */

    public function getDOM()

    {

        return $this->_element;

    }

    /**

     * Update the object from a DOM element

     *

     * Take a DOMElement object, which may be originally from a call

     * to getDOM() or may be custom created, and use it as the

     * DOM tree for this Zend_Feed_Element.

     *

     * @param  DOMElement $element

     * @return void

     */

    public function setDOM(DOMElement $element)

    {

        $this->_element = $this->_element->ownerDocument->importNode($element, true);

    }

    /**

     * Set the parent element of this object to another

     * Zend_Feed_Element.

     *

     * @param  Zend_Feed_Element $element

     * @return void

     */

    public function setParent(Zend_Feed_Element $element)

    {

        $this->_parentElement = $element;

        $this->_appended = false;

    }

    /**

     * Appends this element to its parent if necessary.

     *

     * @return void

     */

    protected function ensureAppended()

    {

        if (!$this->_appended) {

            $this->_parentElement->getDOM()->appendChild($this->_element);

            $this->_appended = true;

            $this->_parentElement->ensureAppended();

        }

    }

    /**

     * Get an XML string representation of this element

     *

     * Returns a string of this element's XML, including the XML

     * prologue.

     *

     * @return string

     */

    public function saveXml()

    {

        // Return a complete document including XML prologue.

        $doc = new DOMDocument($this->_element->ownerDocument->version,

                               $this->_element->ownerDocument->actualEncoding);

        $doc->appendChild($doc->importNode($this->_element, true));

        return $doc->saveXML();

    }

    /**

     * Get the XML for only this element

     *

     * Returns a string of this element's XML without prologue.

     *

     * @return string

     */

    public function saveXmlFragment()

    {

        return $this->_element->ownerDocument->saveXML($this->_element);

    }

    /**

     * Get encoding

     *

     * @return string

     */

    public function getEncoding()

    {

        return $this->_encoding;

    }

    /**

     * Set encoding

     *

     * @param  string $value Encoding to use

     * @return Zend_Feed_Element

     */

    public function setEncoding($value)

    {

        $this->_encoding = (string) $value;

        return $this;

    }

    /**

     * Map variable access onto the underlying entry representation.

     *

     * Get-style access returns a Zend_Feed_Element representing the

     * child element accessed. To get string values, use method syntax

     * with the __call() overriding.

     *

     * @param  string $var The property to access.

     * @return mixed

     */

    public function __get($var)

    {

        $nodes = $this->_children($var);

        $length = count($nodes);

        if ($length == 1) {

            return new Zend_Feed_Element($nodes[0]);

        } elseif ($length > 1) {

            return array_map(create_function('$e', 'return new Zend_Feed_Element($e);'), $nodes);

        } else {

            // When creating anonymous nodes for __set chaining, don't

            // call appendChild() on them. Instead we pass the current

            // element to them as an extra reference; the child is

            // then responsible for appending itself when it is

            // actually set. This way "if ($foo->bar)" doesn't create

            // a phantom "bar" element in our tree.

            if (strpos($var, ':') !== false) {

                list($ns, $elt) = explode(':', $var, 2);

                $node = $this->_element->ownerDocument->createElementNS(Zend_Feed::lookupNamespace($ns), $elt);

            } else {

                $node = $this->_element->ownerDocument->createElement($var);

            }

            $node = new self($node);

            $node->setParent($this);

            return $node;

        }

    }

    /**

     * Map variable sets onto the underlying entry representation.

     *

     * @param  string $var The property to change.

     * @param  string $val The property's new value.

     * @return void

     * @throws Zend_Feed_Exception

     */

    public function __set($var, $val)

    {

        $this->ensureAppended();

        $nodes = $this->_children($var);

        if (!$nodes) {

            if (strpos($var, ':') !== false) {

                list($ns, $elt) = explode(':', $var, 2);

                $node = $this->_element->ownerDocument->createElementNS(Zend_Feed::lookupNamespace($ns),

                    $var, htmlspecialchars($val, ENT_NOQUOTES, $this->getEncoding()));

                $this->_element->appendChild($node);

            } else {

                $node = $this->_element->ownerDocument->createElement($var,

                    htmlspecialchars($val, ENT_NOQUOTES, $this->getEncoding()));

                $this->_element->appendChild($node);

            }

        } elseif (count($nodes) > 1) {

            /**

             * @see Zend_Feed_Exception

             */

            require_once 'Zend/Feed/Exception.php';

            throw new Zend_Feed_Exception('Cannot set the value of multiple tags simultaneously.');

        } else {

            $nodes[0]->nodeValue = $val;

        }

    }

    /**

     * Map isset calls onto the underlying entry representation.

     *

     * @param  string $var

     * @return boolean

     */

    public function __isset($var)

    {

        // Look for access of the form {ns:var}. We don't use

        // _children() here because we can break out of the loop

        // immediately once we find something.

        if (strpos($var, ':') !== false) {

            list($ns, $elt) = explode(':', $var, 2);

            foreach ($this->_element->childNodes as $child) {

                if ($child->localName == $elt && $child->prefix == $ns) {

                    return true;

                }

            }

        } else {

            foreach ($this->_element->childNodes as $child) {

                if ($child->localName == $var) {

                    return true;

                }

            }

        }

    }

    /**

     * Get the value of an element with method syntax.

     *

     * Map method calls to get the string value of the requested

     * element. If there are multiple elements that match, this will

     * return an array of those objects.

     *

     * @param  string $var    The element to get the string value of.

     * @param  mixed  $unused This parameter is not used.

     * @return mixed The node's value, null, or an array of nodes.

     */

    public function __call($var, $unused)

    {

        $nodes = $this->_children($var);

        if (!$nodes) {

            return null;

        } elseif (count($nodes) > 1) {

            return $nodes;

        } else {

            return $nodes[0]->nodeValue;

        }

    }

    /**

     * Remove all children matching $var.

     *

     * @param  string $var

     * @return void

     */

    public function __unset($var)

    {

        $nodes = $this->_children($var);

        foreach ($nodes as $node) {

            $parent = $node->parentNode;

            $parent->removeChild($node);

        }

    }

    /**

     * Returns the nodeValue of this element when this object is used

     * in a string context.

     *

     * @return string

     */

    public function __toString()

    {

        return $this->_element->nodeValue;

    }

    /**

     * Finds children with tagnames matching $var

     *

     * Similar to SimpleXML's children() method.

     *

     * @param  string $var Tagname to match, can be either namespace:tagName or just tagName.

     * @return array

     */

    protected function _children($var)

    {

        $found = array();

        // Look for access of the form {ns:var}.

        if (strpos($var, ':') !== false) {

            list($ns, $elt) = explode(':', $var, 2);

            foreach ($this->_element->childNodes as $child) {

                if ($child->localName == $elt && $child->prefix == $ns) {

                    $found[] = $child;

                }

            }

        } else {

            foreach ($this->_element->childNodes as $child) {

                if ($child->localName == $var) {

                    $found[] = $child;

                }

            }

        }

        return $found;

    }

    /**

     * Required by the ArrayAccess interface.

     *

     * @param  string $offset

     * @return boolean

     */

    public function offsetExists($offset)

    {

        if (strpos($offset, ':') !== false) {

            list($ns, $attr) = explode(':', $offset, 2);

            return $this->_element->hasAttributeNS(Zend_Feed::lookupNamespace($ns), $attr);

        } else {

            return $this->_element->hasAttribute($offset);

        }

    }

    /**

     * Required by the ArrayAccess interface.

     *

     * @param  string $offset

     * @return string

     */

    public function offsetGet($offset)

    {

        if (strpos($offset, ':') !== false) {

            list($ns, $attr) = explode(':', $offset, 2);

            return $this->_element->getAttributeNS(Zend_Feed::lookupNamespace($ns), $attr);

        } else {

            return $this->_element->getAttribute($offset);

        }

    }

    /**

     * Required by the ArrayAccess interface.

     *

     * @param  string $offset

     * @param  string $value

     * @return string

     */

    public function offsetSet($offset, $value)

    {

        $this->ensureAppended();

        if (strpos($offset, ':') !== false) {

            list($ns, $attr) = explode(':', $offset, 2);

            // DOMElement::setAttributeNS() requires $qualifiedName to have a prefix

            return $this->_element->setAttributeNS(Zend_Feed::lookupNamespace($ns), $offset, $value);

        } else {

            return $this->_element->setAttribute($offset, $value);

        }

    }

    /**

     * Required by the ArrayAccess interface.

     *

     * @param  string $offset

     * @return boolean

     */

    public function offsetUnset($offset)

    {

        if (strpos($offset, ':') !== false) {

            list($ns, $attr) = explode(':', $offset, 2);

            return $this->_element->removeAttributeNS(Zend_Feed::lookupNamespace($ns), $attr);

        } else {

            return $this->_element->removeAttribute($offset);

        }

    }

}