<?php

/**
 * Class for handling the Logo metadata extensions for login and discovery user interface
 *
 * @link: http://docs.oasis-open.org/security/saml/Post2.0/sstc-saml-metadata-ui/v1.0/sstc-saml-metadata-ui-v1.0.pdf
 * @package simpleSAMLphp
 * @version $Id$
 */
class SAML2_XML_mdui_Logo {

	/**
	 * The url of this logo.
	 *
	 * @var string
	 */
	public $url;


	/**
	 * The width of this logo.
	 *
	 * @var string
	 */
	public $width;


	/**
	 * The height of this logo.
	 *
	 * @var string
	 */
	public $height;

	/**
	 * The language of this item.
	 *
	 * @var string
	 */
	public $lang;


	/**
	 * Initialize a Logo.
	 *
	 * @param DOMElement|NULL $xml  The XML element we should load.
	 */
	public function __construct(DOMElement $xml = NULL) {

		if ($xml === NULL) {
			return;
		}

		if (!$xml->hasAttribute('width')) {
			throw new Exception('Missing width of Logo.');
		}
		if (!$xml->hasAttribute('height')) {
			throw new Exception('Missing height of Logo.');
		}
		if (!is_string($xml->textContent) || !strlen($xml->textContent)) {
			throw new Exception('Missing url value for Logo.');
		}
		$this->url = $xml->textContent;
		$this->width = (int)$xml->getAttribute('width');
		$this->height = (int)$xml->getAttribute('height');
		$this->lang = $xml->hasAttribute('xml:lang') ? $xml->getAttribute('xml:lang') : NULL;
	}


	/**
	 * Convert this Logo to XML.
	 *
	 * @param DOMElement $parent  The element we should append this Logo to.
	 */
	public function toXML(DOMElement $parent) {
		assert('is_int($this->width)');
		assert('is_int($this->height)');
		assert('is_string($this->url)');

		$doc = $parent->ownerDocument;

		$e = $doc->createElementNS(SAML2_XML_mdui_UIInfo::NS, 'mdui:Logo');
		$e->nodeValue = $this->url;
		$e->setAttribute('width', (int)$this->width);
		$e->setAttribute('height', (int)$this->height);
		if (isset($this->lang)) {
			$e->setAttribute('xml:lang', $this->lang);
		}
		$parent->appendChild($e);

		return $e;
	}

}
