<?php

/**
 * @file classes/citation/XmlWebService.inc.php
 *
 * Copyright (c) 2013-2015 Simon Fraser University Library
 * Copyright (c) 2000-2015 John Willinsky
 * Distributed under the GNU GPL v2. For full terms see the file docs/COPYING.
 *
 * @class XmlWebService
 * @ingroup webservice
 *
 * @brief A web service that returns XML data.
 */


import('lib.pkp.classes.webservice.WebService');
import('lib.pkp.classes.xslt.XSLTransformer');

class XmlWebService extends WebService {
	/** @var integer */
	var $_returnType;

	/**
	 * Constructor
	 */
	function XmlWebService() {
		if (checkPhpVersion('5.0.0') && extension_loaded('dom')) {
			$this->_returnType = XSL_TRANSFORMER_DOCTYPE_DOM;
		} else {
			$this->_returnType = XSL_TRANSFORMER_DOCTYPE_STRING;
		}
	}

	/**
	 * Get the return type
	 * @return integer
	 */
	function getReturnType() {
		return $this->_returnType;
	}

	/**
	 * Set the return type
	 * @param $returnType integer
	 */
	function setReturnType($returnType) {
		if ($returnType == XSL_TRANSFORMER_DOCTYPE_DOM) {
			if (!checkPhpVersion('5.0.0') || !extension_loaded('dom')) {
				fatalError('This system does not meet minimum requirements!');
			}
		}

		$this->_returnType = $returnType;
	}


	/**
	 * @see WebService::call()
	 * @param $webServiceRequest WebServiceRequest
	 * @return DOMDocument|string the result of the web service or null in case of an error.
	 */
	function &call(&$webServiceRequest) {
		// Call the web service
		$xmlResult = parent::call($webServiceRequest);

		// Catch web service errors
		if (is_null($xmlResult)) return $xmlResult;

		if ($this->_lastResponseStatus >= 400 && $this->_lastResponseStatus <= 599) {
			$nullVar = null;
			return $nullVar;
		}

		switch ($this->_returnType) {
			case XSL_TRANSFORMER_DOCTYPE_DOM:
				// Create DOM document
				$resultDOM = new DOMDocument('1.0', Config::getVar('i18n', 'client_charset'));
				// Try to handle non-well-formed responses
				$resultDOM->recover = true;
				$resultDOM->loadXML($xmlResult);
				return $resultDOM;

			case XSL_TRANSFORMER_DOCTYPE_STRING:
				return $xmlResult;

			default:
				assert(false);
		}
	}
}
?>