<?php
  
  /**
   * ownCloud – LDAP Wrapper
   *
   * @author Arthur Schiwon
   * @copyright 2013 Arthur Schiwon blizzz@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/>.
   *
   */
  
  namespace OCA\user_ldap\lib;
  
  class LDAP implements ILDAPWrapper {
  	protected $curFunc = '';
  	protected $curArgs = array();

  	/**
  	 * @param resource $link
  	 * @param string $dn
  	 * @param string $password
  	 * @return bool|mixed
  	 */

  	public function bind($link, $dn, $password) {
  		return $this->invokeLDAPMethod('bind', $link, $dn, $password);
  	}

  	/**
  	 * @param string $host
  	 * @param string $port
  	 * @return mixed
  	 */

  	public function connect($host, $port) {
  		return $this->invokeLDAPMethod('connect', $host, $port);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param LDAP $result
  	 * @param string $cookie
  	 * @return bool|LDAP
  	 */

  	public function controlPagedResultResponse($link, $result, &$cookie) {
  		$this->preFunctionCall('ldap_control_paged_result_response',
  			array($link, $result, $cookie));
  		$result = ldap_control_paged_result_response($link, $result, $cookie);
  		$this->postFunctionCall();
  
  		return $result;
  	}

  	/**
  	 * @param LDAP $link
  	 * @param int $pageSize
  	 * @param bool $isCritical
  	 * @param string $cookie
  	 * @return mixed|true
  	 */
  	public function controlPagedResult($link, $pageSize, $isCritical, $cookie) {
  		return $this->invokeLDAPMethod('control_paged_result', $link, $pageSize,

  										$isCritical, $cookie);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param LDAP $result
  	 * @return mixed
  	 */

  	public function countEntries($link, $result) {
  		return $this->invokeLDAPMethod('count_entries', $link, $result);
  	}

  	/**
  	 * @param LDAP $link
  	 * @return mixed|string
  	 */

  	public function errno($link) {
  		return $this->invokeLDAPMethod('errno', $link);
  	}

  	/**
  	 * @param LDAP $link
  	 * @return int|mixed
  	 */

  	public function error($link) {
  		return $this->invokeLDAPMethod('error', $link);
  	}

  	/**
  	 * Splits DN into its component parts
  	 * @param string $dn
  	 * @param int @withAttrib
  	 * @return array|false
  	 * @link http://www.php.net/manual/en/function.ldap-explode-dn.php
  	 */
  	public function explodeDN($dn, $withAttrib) {

  		return $this->invokeLDAPMethod('explode_dn', $dn, $withAttrib);

  	}
  
  	/**
  	 * @param LDAP $link
  	 * @param LDAP $result
  	 * @return mixed
  	 */

  	public function firstEntry($link, $result) {
  		return $this->invokeLDAPMethod('first_entry', $link, $result);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param LDAP $result
  	 * @return array|mixed
  	 */

  	public function getAttributes($link, $result) {
  		return $this->invokeLDAPMethod('get_attributes', $link, $result);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param LDAP $result
  	 * @return mixed|string
  	 */

  	public function getDN($link, $result) {
  		return $this->invokeLDAPMethod('get_dn', $link, $result);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param LDAP $result
  	 * @return array|mixed
  	 */

  	public function getEntries($link, $result) {
  		return $this->invokeLDAPMethod('get_entries', $link, $result);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param resource $result
  	 * @return mixed|an
  	 */

  	public function nextEntry($link, $result) {
  		return $this->invokeLDAPMethod('next_entry', $link, $result);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param string $baseDN
  	 * @param string $filter
  	 * @param array $attr
  	 * @return mixed
  	 */

  	public function read($link, $baseDN, $filter, $attr) {
  		return $this->invokeLDAPMethod('read', $link, $baseDN, $filter, $attr);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param string $baseDN
  	 * @param string $filter
  	 * @param array $attr
  	 * @param int $attrsOnly
  	 * @param int $limit
  	 * @return mixed
  	 */
  	public function search($link, $baseDN, $filter, $attr, $attrsOnly = 0, $limit = 0) {
  		return $this->invokeLDAPMethod('search', $link, $baseDN, $filter, $attr, $attrsOnly, $limit);

  	}

  	/**
  	 * @param LDAP $link
  	 * @param string $option
  	 * @param int $value
  	 * @return bool|mixed
  	 */

  	public function setOption($link, $option, $value) {
  		return $this->invokeLDAPMethod('set_option', $link, $option, $value);
  	}

  	/**
  	 * @param LDAP $link
  	 * @param LDAP $result
  	 * @param string $sortFilter
  	 * @return mixed
  	 */
  	public function sort($link, $result, $sortFilter) {
  		return $this->invokeLDAPMethod('sort', $link, $result, $sortFilter);

  	}

  	/**
  	 * @param LDAP $link
  	 * @return mixed|true
  	 */

  	public function startTls($link) {
  		return $this->invokeLDAPMethod('start_tls', $link);
  	}

  	/**
  	 * @param resource $link
  	 * @return bool|mixed
  	 */

  	public function unbind($link) {
  		return $this->invokeLDAPMethod('unbind', $link);
  	}
  
  	/**

  	 * Checks whether the server supports LDAP
  	 * @return boolean if it the case, false otherwise

  	 * */
  	public function areLDAPFunctionsAvailable() {
  		return function_exists('ldap_connect');
  	}
  
  	/**

  	 * Checks whether PHP supports LDAP Paged Results
  	 * @return boolean if it the case, false otherwise

  	 * */
  	public function hasPagedResultSupport() {
  		$hasSupport = function_exists('ldap_control_paged_result')
  			&& function_exists('ldap_control_paged_result_response');
  		return $hasSupport;
  	}
  
  	/**

  	 * Checks whether the submitted parameter is a resource
  	 * @param Resource $resource the resource variable to check
  	 * @return bool true if it is a resource, false otherwise

  	 */
  	public function isResource($resource) {
  		return is_resource($resource);
  	}

  	/**
  	 * @return mixed
  	 */

  	private function invokeLDAPMethod() {
  		$arguments = func_get_args();
  		$func = 'ldap_' . array_shift($arguments);
  		if(function_exists($func)) {
  			$this->preFunctionCall($func, $arguments);
  			$result = call_user_func_array($func, $arguments);

  			if ($result === FALSE) {
  				$this->postFunctionCall();
  			}

  			return $result;
  		}
  	}

  	/**
  	 * @param string $functionName
  	 * @param array $args
  	 */

  	private function preFunctionCall($functionName, $args) {
  		$this->curFunc = $functionName;
  		$this->curArgs = $args;
  	}
  
  	private function postFunctionCall() {
  		if($this->isResource($this->curArgs[0])) {
  			$errorCode = ldap_errno($this->curArgs[0]);
  			$errorMsg  = ldap_error($this->curArgs[0]);
  			if($errorCode !== 0) {
  				if($this->curFunc === 'ldap_sort' && $errorCode === -4) {
  					//You can safely ignore that decoding error.
  					//… says https://bugs.php.net/bug.php?id=18023
  				} else if($this->curFunc === 'ldap_get_entries'
  						  && $errorCode === -4) {
  				} else if ($errorCode === 32) {
  					//for now
  				} else if ($errorCode === 10) {
  					//referrals, we switch them off, but then there is AD :)
  				} else {
  					\OCP\Util::writeLog('user_ldap',
  										'LDAP error '.$errorMsg.' (' .
  											$errorCode.') after calling '.
  											$this->curFunc,
  										\OCP\Util::DEBUG);
  				}
  			}
  		}
  
  		$this->curFunc = '';
  		$this->curArgs = array();
  	}

  }