<?php

/**
* ownCloud
*
* @author Frank Karlitschek
* @author Michael Gapczynski
* @copyright 2012 Frank Karlitschek frank@owncloud.org
* @copyright 2012 Michael Gapczynski mtgap@owncloud.com
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library.  If not, see <http://www.gnu.org/licenses/>.
*
*/

/**
 * Class to handle open collaboration services API requests
 *
 */
class OC_OCS {

	/**
	* reads input date from get/post/cookies and converts the date to a special data-type
	*
	* @param string HTTP method to read the key from
	* @param string Parameter to read
	* @param string Variable type to format data
	* @param mixed Default value to return if the key is not found
	* @return mixed Data or if the key is not found and no default is set it will exit with a 400 Bad request
	*/
	public static function readData($method, $key, $type = 'raw', $default = null) {
		if ($method == 'get') {
			if (isset($_GET[$key])) {
				$data = $_GET[$key];
			} else if (isset($default)) {
				return $default;
			} else {
				$data = false;
			}
		} else if ($method == 'post') {
			if (isset($_POST[$key])) {
				$data = $_POST[$key];
			} else if (isset($default)) {
				return $default;
			} else {
				$data = false;
			}
		}
		if ($data === false) {
			echo self::generateXml('', 'fail', 400, 'Bad request. Please provide a valid '.$key);
			exit();
		} else {
			// NOTE: Is the raw type necessary? It might be a little risky without sanitization
			if ($type == 'raw') return $data;
			elseif ($type == 'text') return OC_Util::sanitizeHTML($data);
			elseif ($type == 'int')  return (int) $data;
			elseif ($type == 'float') return (float) $data;
			elseif ($type == 'array') return OC_Util::sanitizeHTML($data);
			else return OC_Util::sanitizeHTML($data);
		}
	}

	public static function notFound() {
		if($_SERVER['REQUEST_METHOD'] == 'GET') {
			$method='get';
		}elseif($_SERVER['REQUEST_METHOD'] == 'PUT') {
			$method='put';
			parse_str(file_get_contents("php://input"),$put_vars);
		}elseif($_SERVER['REQUEST_METHOD'] == 'POST') {
			$method='post';
		}else{
			echo('internal server error: method not supported');
			exit();
		}
		$format = self::readData($method, 'format', 'text', '');
		$txt='Invalid query, please check the syntax. API specifications are here: http://www.freedesktop.org/wiki/Specifications/open-collaboration-services. DEBUG OUTPUT:'."\n";
		$txt.=OC_OCS::getDebugOutput();
		echo(OC_OCS::generateXml($format,'failed',999,$txt));
	}

	/**
	* generated some debug information to make it easier to find faild API calls
	* @return debug data string
	*/
	private static function getDebugOutput() {
		$txt='';
		$txt.="debug output:\n";
		if(isset($_SERVER['REQUEST_METHOD'])) $txt.='http request method: '.$_SERVER['REQUEST_METHOD']."\n";
		if(isset($_SERVER['REQUEST_URI'])) $txt.='http request uri: '.$_SERVER['REQUEST_URI']."\n";
		if(isset($_GET)) foreach($_GET as $key=>$value) $txt.='get parameter: '.$key.'->'.$value."\n";
		if(isset($_POST)) foreach($_POST as $key=>$value) $txt.='post parameter: '.$key.'->'.$value."\n";
		return($txt);
	}

	/**
	* checks if the user is authenticated
	* checks the IP whitlist, apikeys and login/password combination
	* if $forceuser is true and the authentication failed it returns an 401 http response.
	* if $forceuser is false and authentification fails it returns an empty username string
	* @param bool $forceuser
	* @return username string
	*/
	private static function checkPassword($forceuser=true) {
		//valid user account ?
		if(isset($_SERVER['PHP_AUTH_USER'])) $authuser=$_SERVER['PHP_AUTH_USER']; else $authuser='';
		if(isset($_SERVER['PHP_AUTH_PW']))   $authpw=$_SERVER['PHP_AUTH_PW']; else $authpw='';

		if(empty($authuser)) {
			if($forceuser){
				header('WWW-Authenticate: Basic realm="your valid user account or api key"');
				header('HTTP/1.0 401 Unauthorized');
				exit;
			}else{
				$identifieduser='';
			}
		}else{
			if(!OC_User::login($authuser,$authpw)){
				if($forceuser){
					header('WWW-Authenticate: Basic realm="your valid user account or api key"');
					header('HTTP/1.0 401 Unauthorized');
					exit;
				}else{
					$identifieduser='';
				}
			}else{
				$identifieduser=$authuser;
			}
		}

		return($identifieduser);
	}


	/**
	* generates the xml or json response for the API call from an multidimenional data array.
	* @param string $format
	* @param string $status
	* @param string $statuscode
	* @param string $message
	* @param array $data
	* @param string $tag
	* @param string $tagattribute
	* @param int $dimension
	* @param int $itemscount
	* @param int $itemsperpage
	* @return string xml/json
	*/
	private static function generateXml($format,$status,$statuscode,$message,$data=array(),$tag='',$tagattribute='',$dimension=-1,$itemscount='',$itemsperpage='') {
		if($format=='json') {
			$json=array();
			$json['status']=$status;
			$json['statuscode']=$statuscode;
			$json['message']=$message;
			$json['totalitems']=$itemscount;
			$json['itemsperpage']=$itemsperpage;
			$json['data']=$data;
			return(json_encode($json));
		}else{
			$txt='';
			$writer = xmlwriter_open_memory();
			xmlwriter_set_indent( $writer, 2 );
			xmlwriter_start_document($writer );
			xmlwriter_start_element($writer,'ocs');
			xmlwriter_start_element($writer,'meta');
			xmlwriter_write_element($writer,'status',$status);
			xmlwriter_write_element($writer,'statuscode',$statuscode);
			xmlwriter_write_element($writer,'message',$message);
			if($itemscount<>'') xmlwriter_write_element($writer,'totalitems',$itemscount);
			if(!empty($itemsperpage)) xmlwriter_write_element($writer,'itemsperpage',$itemsperpage);
			xmlwriter_end_element($writer);
			if($dimension=='0') {
				// 0 dimensions
				xmlwriter_write_element($writer,'data',$data);

			}elseif($dimension=='1') {
				xmlwriter_start_element($writer,'data');
				foreach($data as $key=>$entry) {
				xmlwriter_write_element($writer,$key,$entry);
				}
				xmlwriter_end_element($writer);

			}elseif($dimension=='2') {
				xmlwriter_start_element($writer,'data');
				foreach($data as $entry) {
				xmlwriter_start_element($writer,$tag);
				if(!empty($tagattribute)) {
				xmlwriter_write_attribute($writer,'details',$tagattribute);
				}
				foreach($entry as $key=>$value) {
				if(is_array($value)){
				foreach($value as $k=>$v) {
					xmlwriter_write_element($writer,$k,$v);
				}
				} else {
				xmlwriter_write_element($writer,$key,$value);
				}
				}
				xmlwriter_end_element($writer);
				}
				xmlwriter_end_element($writer);

			}elseif($dimension=='3') {
				xmlwriter_start_element($writer,'data');
				foreach($data as $entrykey=>$entry) {
				xmlwriter_start_element($writer,$tag);
				if(!empty($tagattribute)) {
				xmlwriter_write_attribute($writer,'details',$tagattribute);
				}
				foreach($entry as $key=>$value) {
				if(is_array($value)){
				xmlwriter_start_element($writer,$entrykey);
				foreach($value as $k=>$v) {
					xmlwriter_write_element($writer,$k,$v);
				}
				xmlwriter_end_element($writer);
				} else {
				xmlwriter_write_element($writer,$key,$value);
				}
				}
				xmlwriter_end_element($writer);
				}
				xmlwriter_end_element($writer);
			}elseif($dimension=='dynamic') {
				xmlwriter_start_element($writer,'data');
				OC_OCS::toxml($writer,$data,'comment');
				xmlwriter_end_element($writer);
			}

			xmlwriter_end_element($writer);

			xmlwriter_end_document( $writer );
			$txt.=xmlwriter_output_memory( $writer );
			unset($writer);
			return($txt);
		}
	}

	public static function toXml($writer,$data,$node) {
		foreach($data as $key => $value) {
			if (is_numeric($key)) {
				$key = $node;
			}
			if (is_array($value)){
				xmlwriter_start_element($writer,$key);
				OC_OCS::toxml($writer,$value,$node);
				xmlwriter_end_element($writer);
			}else{
				xmlwriter_write_element($writer,$key,$value);
			}
		}
	}


	/**
	* return the config data of this server
	* @param string $format
	* @return string xml/json
	*/
	public static function apiConfig($parameters) {
		$format = $parameters['format'];
		$user=OC_OCS::checkpassword(false);
		$url=substr(OCP\Util::getServerHost().$_SERVER['SCRIPT_NAME'],0,-11).'';

		$xml['version']='1.7';
		$xml['website']='ownCloud';
		$xml['host']=OCP\Util::getServerHost();
		$xml['contact']='';
		$xml['ssl']='false';
		echo(OC_OCS::generatexml($format,'ok',100,'',$xml,'config','',1));
	}


	/**
	* check if the provided login/apikey/password is valid
	* @param string $format
	* @param string $login
	* @param string $passwd
	* @return string xml/json
	*/
	private static function personCheck($format,$login,$passwd) {
		if($login<>''){
			if(OC_User::login($login,$passwd)){
				$xml['person']['personid']=$login;
				echo(OC_OCS::generatexml($format,'ok',100,'',$xml,'person','check',2));
			}else{
				echo(OC_OCS::generatexml($format,'failed',102,'login not valid'));
			}
		}else{
			echo(OC_OCS::generatexml($format,'failed',101,'please specify all mandatory fields'));
		}
	}


	// ACTIVITY API #############################################

	/**
	* get my activities
	* @param string $format
	* @param string $page
	* @param string $pagesize
	* @return string xml/json
	*/
	private static function activityGet($format,$page,$pagesize) {
		$user=OC_OCS::checkpassword();

			//TODO

		$txt=OC_OCS::generatexml($format,'ok',100,'',$xml,'activity','full',2,$totalcount,$pagesize);
		echo($txt);
	}

	/**
	* submit a activity
	* @param string $format
	* @param string $message
	* @return string xml/json
	*/
	private static function activityPut($format,$message) {
		// not implemented in ownCloud
		$user=OC_OCS::checkpassword();
		echo(OC_OCS::generatexml($format,'ok',100,''));
	}

	// PRIVATEDATA API #############################################

	/**
	* get private data and create the xml for ocs
	* @param string $format
	* @param string $app
	* @param string $key
	* @return string xml/json
	*/
	private static function privateDataGet($format,$app="",$key="") {
		$user=OC_OCS::checkpassword();
		$result=OC_OCS::getData($user,$app,$key);
		$xml=array();
		foreach($result as $i=>$log) {
			$xml[$i]['key']=$log['key'];
			$xml[$i]['app']=$log['app'];
			$xml[$i]['value']=$log['value'];
		}


		$txt=OC_OCS::generatexml($format, 'ok', 100, '', $xml, 'privatedata', 'full', 2, count($xml), 0);//TODO: replace 'privatedata' with 'attribute' once a new libattice has been released that works with it
		echo($txt);
	}

	/**
	* set private data referenced by $key to $value and generate the xml for ocs
	* @param string $format
	* @param string $app
	* @param string $key
	* @param string $value
	* @return string xml/json
	*/
	private static function privateDataSet($format, $app, $key, $value) {
		$user=OC_OCS::checkpassword();
		if(OC_OCS::setData($user,$app,$key,$value)){
			echo(OC_OCS::generatexml($format,'ok',100,''));
		}
	}

	/**
	* delete private data referenced by $key and generate the xml for ocs
	* @param string $format
	* @param string $app
	* @param string $key
	* @return string xml/json
	*/
	private static function privateDataDelete($format, $app, $key) {
		if($key=="" or $app==""){
			return; //key and app are NOT optional here
		}
		$user=OC_OCS::checkpassword();
		if(OC_OCS::deleteData($user,$app,$key)){
			echo(OC_OCS::generatexml($format,'ok',100,''));
		}
	}
	
	/**
	* get private data
	* @param string $user
	* @param string $app
	* @param string $key
	* @param bool $like use LIKE instead of = when comparing keys
	* @return array
	*/
	public static function getData($user,$app="",$key="") {
		if($app){
			$apps=array($app);
		}else{
			$apps=OC_Preferences::getApps($user);
		}
		if($key){
			$keys=array($key);
		}else{
			foreach($apps as $app){
				$keys=OC_Preferences::getKeys($user,$app);
			}
		}
		$result=array();
		foreach($apps as $app){
			foreach($keys as $key){
				$value=OC_Preferences::getValue($user,$app,$key);
				$result[]=array('app'=>$app,'key'=>$key,'value'=>$value);
			}
		}
		return $result;
	}

	/**
	* set private data referenced by $key to $value
	* @param string $user
	* @param string $app
	* @param string $key
	* @param string $value
	* @return bool
	*/
	public static function setData($user, $app, $key, $value) {
		return OC_Preferences::setValue($user,$app,$key,$value);
	}

	/**
	* delete private data referenced by $key
	* @param string $user
	* @param string $app
	* @param string $key
	* @return string xml/json
	*/
	public static function deleteData($user, $app, $key) {
		return OC_Preferences::deleteKey($user,$app,$key);
	}


        // CLOUD API #############################################

        /**
        * get a list of installed web apps
        * @param string $format
        * @return string xml/json
        */
        private static function systemWebApps($format) {
                $login=OC_OCS::checkpassword();
		$apps=OC_App::getEnabledApps();
		$values=array();
		foreach($apps as $app) {
			$info=OC_App::getAppInfo($app);
			if(isset($info['standalone'])) {
				$newvalue=array('name'=>$info['name'],'url'=>OC_Helper::linkToAbsolute($app,''),'icon'=>'');
				$values[]=$newvalue;
			}

		}
		$txt=OC_OCS::generatexml($format, 'ok', 100, '', $values, 'cloud', '', 2, 0, 0);
		echo($txt);

        }


        /**
        * get the quota of a user
        * @param string $format
        * @param string $user
        * @return string xml/json
        */
        private static function quotaGet($format,$user) {
                $login=OC_OCS::checkpassword();
		if(OC_Group::inGroup($login, 'admin') or ($login==$user)) {

			if(OC_User::userExists($user)){
				// calculate the disc space
				$user_dir = '/'.$user.'/files';
				OC_Filesystem::init($user_dir);
				$rootInfo=OC_FileCache::get('');
				$sharedInfo=OC_FileCache::get('/Shared');
				$used=$rootInfo['size']-$sharedInfo['size'];
				$free=OC_Filesystem::free_space();
				$total=$free+$used;
				if($total==0) $total=1;  // prevent division by zero
				$relative=round(($used/$total)*10000)/100;

				$xml=array();
				$xml['quota']=$total;
				$xml['free']=$free;
				$xml['used']=$used;
				$xml['relative']=$relative;

				$txt=OC_OCS::generatexml($format, 'ok', 100, '', $xml, 'cloud', '', 1, 0, 0);
				echo($txt);
			}else{
				echo self::generateXml('', 'fail', 300, 'User does not exist');
			}
		}else{
			echo self::generateXml('', 'fail', 300, 'You don´t have permission to access this ressource.');
		}
        }

        /**
        * set the quota of a user
        * @param string $format
        * @param string $user
        * @param string $quota
        * @return string xml/json
        */
        private static function quotaSet($format,$user,$quota) {
                $login=OC_OCS::checkpassword();
                if(OC_Group::inGroup($login, 'admin')) {

			// todo
			// not yet implemented
			// add logic here
			error_log('OCS call: user:'.$user.' quota:'.$quota);

                        $xml=array();
                        $txt=OC_OCS::generatexml($format, 'ok', 100, '', $xml, 'cloud', '', 1, 0, 0);
                        echo($txt);
                }else{
                        echo self::generateXml('', 'fail', 300, 'You don´t have permission to access this ressource.');
                }
        }

        /**
        * get the public key of a user
        * @param string $format
        * @param string $user
        * @return string xml/json
        */
        private static function publicKeyGet($format,$user) {
                $login=OC_OCS::checkpassword();

		if(OC_User::userExists($user)){
			// calculate the disc space
			$txt='this is the public key of '.$user;
			echo($txt);
		}else{
			echo self::generateXml('', 'fail', 300, 'User does not exist');
		}
	}

        /**
        * get the private key of a user
        * @param string $format
        * @param string $user
        * @return string xml/json
        */
        private static function privateKeyGet($format,$user) {
                $login=OC_OCS::checkpassword();
                if(OC_Group::inGroup($login, 'admin') or ($login==$user)) {

                        if(OC_User::userExists($user)){
                                // calculate the disc space
                                $txt='this is the private key of '.$user;
                                echo($txt);
                        }else{
                                echo self::generateXml('', 'fail', 300, 'User does not exist');
                        }
                }else{
                        echo self::generateXml('', 'fail', 300, 'You don´t have permission to access this ressource.');
                }
        }


}