<?php
/**
 * EGroupware: ActiveSync access: Addressbook plugin
 *
 * @link http://www.egroupware.org
 * @package addressbook
 * @subpackage activesync
 * @author Ralf Becker <rb@stylite.de>
 * @author Klaus Leithoff <kl@stylite.de>
 * @author Philip Herbert <philip@knauber.de>
 * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
 * @version $Id$
 */

/**
 * Addressbook activesync plugin
 */
class addressbook_activesync implements activesync_plugin_write, activesync_plugin_search_gal
{
	/**
	 * @var BackendEGW
	 */
	private $backend;

	/**
	 * Instance of addressbook_bo
	 *
	 * @var addressbook_bo
	 */
	private $addressbook;

	/**
	 * Mapping of ActiveSync SyncContact attributes to EGroupware contact array-keys
	 *
	 * @var array
	 */
	static public $mapping = array(
		//'anniversary'	=> '',
		'assistantname'	=> 'assistent',
		'assistnamephonenumber'	=> 'tel_assistent',
		'birthday'	=>	'bday',
		'body'	=> 'note',
		//'bodysize'	=> '',
		//'bodytruncated'	=> '',
		//'business2phonenumber'	=> '',
		'businesscity'	=>	'adr_one_locality',
		'businesscountry'	=> 'adr_one_countryname',
		'businesspostalcode'	=> 'adr_one_postalcode',
		'businessstate'	=> 'adr_one_region',
		'businessstreet'	=> 'adr_one_street',
		'businessfaxnumber'	=> 'tel_fax',
		'businessphonenumber'	=> 'tel_work',
		'carphonenumber'	=> 'tel_car',
		'categories'	=> 'cat_id',
		//'children'	=> '',
		'companyname'	=> 'org_name',
		'department'	=>	'org_unit',
		'email1address'	=> 'email',
		'email2address'	=> 'email_home',
		//'email3address'	=> '',
		'fileas'	=>	'n_fileas',
		'firstname'	=>	'n_given',
		//'home2phonenumber'	=> '',
		'homecity'	=> 'adr_two_locality',
		'homecountry'	=> 'adr_two_countryname',
		'homepostalcode'	=> 'adr_two_postalcode',
		'homestate'	=> 'adr_two_region',
		'homestreet'	=>	'adr_two_street',
		'homefaxnumber'	=> 'tel_fax_home',
		'homephonenumber'	=>	'tel_home',
		'jobtitle'	=>	'role',
		'lastname'	=> 'n_family',
		'middlename'	=> 'n_middle',
		'mobilephonenumber'	=> 'tel_cell',
		'officelocation'	=> 'room',
		//'othercity'	=> '',
		//'othercountry'	=> '',
		//'otherpostalcode'	=> '',
		//'otherstate'	=> '',
		//'otherstreet'	=> '',
		'pagernumber'	=> 'tel_pager',
		//'radiophonenumber'	=> '',
		//'spouse'	=> '',
		'suffix'	=>	'n_suffix',
		'title'	=> 'title',	// @TODO: check if n_prefix
		'webpage'	=> 'url',
		//'yomicompanyname'	=> '',
		//'yomifirstname'	=>	'',
		//'yomilastname'	=>	'',
		//'rtf'	=> '',
		'picture'	=> 'jpegphoto',
		//'nickname'	=>	'',
		//'airsyncbasebody'	=>	'',
	);
	/**
	 * ID of private addressbook
	 *
	 * @var int
	 */
	const PRIVATE_AB = 0x7fffffff;

	/**
	 * Constructor
	 *
	 * @param BackendEGW $backend
	 */
	public function __construct(BackendEGW $backend)
	{
		$this->backend = $backend;
	}

	/**
	 * Get addressbooks (no extra private one and do some caching)
	 *
	 * Takes addessbook-abs and addressbook-all-in-one preference into account.
	 *
	 * @param int $account=null account_id of addressbook or null to get array of all addressbooks
	 * @param boolean $return_all_in_one=true if false and all-in-one pref is set, return all selected abs
	 * 	if true only the all-in-one ab is returned (with id of personal ab)
	 * @return string|array addressbook name of array with int account_id => label pairs
	 */
	private function get_addressbooks($account=null,$return_all_in_one=true)
	{
		static $abs;

		if (!isset($abs) || !$resolve_all_in_one)
		{
			if ($return_all_in_one && $GLOBALS['egw_info']['user']['preferences']['activesync']['addressbook-all-in-one'])
			{
				$abs = array(
					$GLOBALS['egw_info']['user']['account_id'] => lang('All'),
				);
			}
			else
			{
				translation::add_app('addressbook');	// we need the addressbook translations

				if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();

				// error_log(print_r($this->addressbook->get_addressbooks(EGW_ACL_READ),true));
				$pref_abs = $GLOBALS['egw_info']['user']['preferences']['activesync']['addressbook-abs'];
				$pref_abs = (string)$pref_abs !== '' ? explode(',',$pref_abs) : array();

				foreach ($this->addressbook->get_addressbooks() as $account_id => $label)
				{
					if ((string)$account_id == $GLOBALS['egw_info']['user']['account_id'].'p')
					{
						$account_id = self::PRIVATE_AB;
					}
					if ($account_id && in_array($account_id,$pref_abs) || in_array('A',$pref_abs) ||
						$account_id == 0 && in_array('U',$pref_abs) ||
						$account_id == $GLOBALS['egw_info']['user']['account_id'] ||	// allways sync pers. AB
						$account_id == $GLOBALS['egw_info']['user']['account_primary_group'] && in_array('G',$pref_abs))
					{
						$abs[$account_id] = $label;
					}
				}
			}
		}
		//error_log(__METHOD__."($account) returning ".array2string(is_null($account) ? $abs : $abs[$account]));
		return is_null($account) ? $abs : $abs[$account];
	}

	/**
	 *  This function is analogous to GetMessageList.
	 *
	 *  @ToDo implement preference, include own private calendar
	 */
	public function GetFolderList()
	{
		// error_log(print_r($this->addressbook->get_addressbooks(EGW_ACL_READ),true));
		$folderlist = array();
		foreach ($this->get_addressbooks() as $account => $label)
		{
			$folderlist[] = array(
				'id'	=>	$this->backend->createID('addressbook',$account),
				'mod'	=>	$label,
				'parent'=>	'0',
			);
		}
		debugLog(__METHOD__."() returning ".array2string($folderlist));
		//error_log(__METHOD__."() returning ".array2string($folderlist));
		return $folderlist;
	}

	/**
	 * Get Information about a folder
	 *
	 * @param string $id
	 * @return SyncFolder|boolean false on error
	 */
	public function GetFolder($id)
	{
		$this->backend->splitID($id, $type, $owner);

		$folderObj = new SyncFolder();
		$folderObj->serverid = $id;
		$folderObj->parentid = '0';
		$folderObj->displayname = $this->get_addressbooks($owner);

		if ($owner == $GLOBALS['egw_info']['user']['account_id'])
		{
			$folderObj->type = SYNC_FOLDER_TYPE_CONTACT;
		}
		else
		{
			$folderObj->type = SYNC_FOLDER_TYPE_USER_CONTACT;
		}
/*
		// not existing folder requested --> return false
		if (is_null($folderObj->displayname))
		{
			$folderObj = false;
			debugLog(__METHOD__."($id) returning ".array2string($folderObj));
		}
*/
		//error_log(__METHOD__."('$id') returning ".array2string($folderObj));
		return $folderObj;
	}

	/**
	 * Return folder stats. This means you must return an associative array with the
	 * following properties:
	 *
	 * "id" => The server ID that will be used to identify the folder. It must be unique, and not too long
	 *		 How long exactly is not known, but try keeping it under 20 chars or so. It must be a string.
	 * "parent" => The server ID of the parent of the folder. Same restrictions as 'id' apply.
	 * "mod" => This is the modification signature. It is any arbitrary string which is constant as long as
	 *		  the folder has not changed. In practice this means that 'mod' can be equal to the folder name
	 *		  as this is the only thing that ever changes in folders. (the type is normally constant)
	 *
	 * @return array with values for keys 'id', 'mod' and 'parent'
	 */
	public function StatFolder($id)
	{
		$this->backend->splitID($id, $type, $owner);

		$stat = array(
			'id'	 => $id,
			'mod'	=> $this->get_addressbooks($owner),
			'parent' => '0',
		);
/*
		// not existing folder requested --> return false
		if (is_null($stat['mod']))
		{
			$stat = false;
			debugLog(__METHOD__."('$id') ".function_backtrace());
		}
*/
		//error_log(__METHOD__."('$id') returning ".array2string($stat));
		debugLog(__METHOD__."('$id') returning ".array2string($stat));
		return $stat;
	}

	/**
	 * Should return a list (array) of messages, each entry being an associative array
	 * with the same entries as StatMessage(). This function should return stable information; ie
	 * if nothing has changed, the items in the array must be exactly the same. The order of
	 * the items within the array is not important though.
	 *
	 * The cutoffdate is a date in the past, representing the date since which items should be shown.
	 * This cutoffdate is determined by the user's setting of getting 'Last 3 days' of e-mail, etc. If
	 * you ignore the cutoffdate, the user will not be able to select their own cutoffdate, but all
	 * will work OK apart from that.
	 *
	 * @todo if AB supports an extra private addressbook and AS prefs want an all-in-one AB, the private AB is always included, even if not selected in the prefs
	 * @param string $id folder id
	 * @param int $cutoffdate=null
	 * @return array
  	 */
	function GetMessageList($id, $cutoffdate=NULL)
	{
		if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();

		$this->backend->splitID($id,$type,$user);
		$filter = array('owner' => $user);

		// handle all-in-one addressbook
		if ($GLOBALS['egw_info']['user']['preferences']['activesync']['addressbook-all-in-one'] &&
			$user == $GLOBALS['egw_info']['user']['account_id'])
		{
			$filter['owner'] = array_keys($this->get_addressbooks(null,false));	// false = return all selected abs
			// translate AS private AB ID to EGroupware one
			if (($key == array_search(self::PRIVATE_AB, $filter['owner'])) !== false)
			{
				$filter['owner'][$key] = $GLOBALS['egw_info']['user']['account_id'].'p';
			}
		}
		// handle private/personal addressbooks
		elseif ($this->addressbook->private_addressbook &&
			($user == self::PRIVATE_AB || $user == $GLOBALS['egw_info']['user']['account_id']))
		{
			$filter['owner'] = $GLOBALS['egw_info']['user']['account_id'];
			$filter['private'] = (int)($user == self::PRIVATE_AB);
		}

		$messagelist = array();
		if (($contacts =& $this->addressbook->search($criteria,'contact_id,contact_etag',$order_by='',$extra_cols='',$wildcard='',
			$empty=false,$op='AND',$start=false,$filter)))
		{
			foreach($contacts as $contact)
			{
				$messagelist[] = $this->StatMessage($id, $contact);
			}
		}
		//error_log(__METHOD__."('$id', $cutoffdate) filter=".array2string($filter)." returning ".count($messagelist).' entries');
		return $messagelist;
	}

	/**
	 * Get specified item from specified folder.
	 *
	 * @param string $folderid
	 * @param string $id
	 * @param int $truncsize
	 * @param int $bodypreference
	 * @param bool $mimesupport
	 * @return $messageobject|boolean false on error
	 */
	public function GetMessage($folderid, $id, $truncsize, $bodypreference=false, $mimesupport = 0)
	{
		if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();

		debugLog (__METHOD__."('$folderid', $id, truncsize=$truncsize, bodyprefence=$bodypreference, mimesupport=$mimesupport)");
		$this->backend->splitID($folderid, $type, $account);
		if ($type != 'addressbook' || !($contact = $this->addressbook->read($id)))
		{
			error_log(__METHOD__."('$folderid',$id,...) Folder wrong (type=$type, account=$account) or contact not existing (read($id)=".array2string($contact).")! returning false");
			return false;
		}
		$message = new SyncContact();
		foreach(self::$mapping as $key => $attr)
		{
			switch ($attr)
			{
				case 'note':
					if ($bodypreference == false)
					{
						$message->body = $contact[$attr];
						$message->bodysize = strlen($message->body);
						$message->bodytruncated = 0;
					}
					else
					{
						debugLog("airsyncbasebody!");
						$message->airsyncbasebody = new SyncAirSyncBaseBody();
						$message->airsyncbasenativebodytype=1;
						$this->backend->note2messagenote($contact[$attr], $bodypreference, $message->airsyncbasebody);
					}
					break;

					case 'jpegphoto':
					if (!empty($contact[$attr])) $message->$key = base64_encode($contact[$attr]);
					break;

				case 'bday':	// zpush seems to use a timestamp in utc (at least vcard backend does)
					if (!empty($contact[$attr]))
					{
            			$tz = date_default_timezone_get();
            			date_default_timezone_set('UTC');
            			$message->birthday = strtotime($contact[$attr]);
            			date_default_timezone_set($tz);
					}
					break;

				case 'cat_id':
					$message->$key = array();
					foreach($contact[$attr] ? explode(',',$contact[$attr]) : array() as $cat_id)
					{
						$message->categories[] = categories::id2name($cat_id);
					}
					break;

				default:
					if (!empty($contact[$attr])) $message->$key = $contact[$attr];
			}
		}
		//error_log(__METHOD__."(folder='$folderid',$id,...) returning ".array2string($message));
		return $message;
	}

	/**
	 * StatMessage should return message stats, analogous to the folder stats (StatFolder). Entries are:
	 * 'id'	 => Server unique identifier for the message. Again, try to keep this short (under 20 chars)
	 * 'flags'	 => simply '0' for unread, '1' for read
	 * 'mod'	=> modification signature. As soon as this signature changes, the item is assumed to be completely
	 *			 changed, and will be sent to the PDA as a whole. Normally you can use something like the modification
	 *			 time for this field, which will change as soon as the contents have changed.
	 *
	 * @param string $folderid
	 * @param int|array $contact contact id or array
	 * @return array
	 */
	public function StatMessage($folderid, $contact)
	{
		if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();

		if (!is_array($contact)) $contact = $this->addressbook->read($contact);

		if (!$contact)
		{
			$stat = false;
		}
		else
		{
			$stat = array(
				'mod' => $contact['etag'],
				'id' => $contact['id'],
				'flags' => 1,
			);
		}
		//debugLog (__METHOD__."('$folderid',".array2string($id).") returning ".array2string($stat));
		//error_log(__METHOD__."('$folderid',$contact) returning ".array2string($stat));
		return $stat;
	}

	/**
	 *  Creates or modifies a folder
	 *
	 * @param $id of the parent folder
	 * @param $oldid => if empty -> new folder created, else folder is to be renamed
	 * @param $displayname => new folder name (to be created, or to be renamed to)
	 * @param type => folder type, ignored in IMAP
	 *
	 * @return stat | boolean false on error
	 *
	 */
	public function ChangeFolder($id, $oldid, $displayname, $type)
	{
		debugLog(__METHOD__." not implemented");
	}

	/**
	 * Deletes (really delete) a Folder
	 *
	 * @param $parentid of the folder to delete
	 * @param $id of the folder to delete
	 *
	 * @return
	 * @TODO check what is to be returned
	 *
	 */
	public function DeleteFolder($parentid, $id)
	{
		debugLog(__METHOD__." not implemented");
	}

	/**
	 * Changes or adds a message on the server
	 *
	 * @param string $folderid
	 * @param int $id for change | empty for create new
	 * @param SyncContact $message object to SyncObject to create
	 *
	 * @return array $stat whatever would be returned from StatMessage
	 *
	 * This function is called when a message has been changed on the PDA. You should parse the new
	 * message here and save the changes to disk. The return value must be whatever would be returned
	 * from StatMessage() after the message has been saved. This means that both the 'flags' and the 'mod'
	 * properties of the StatMessage() item may change via ChangeMessage().
	 * Note that this function will never be called on E-mail items as you can't change e-mail items, you
	 * can only set them as 'read'.
	 */
	public function ChangeMessage($folderid, $id, $message)
	{
		if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();

		$this->backend->splitID($folderid, $type, $account);
		// error_log(__METHOD__. " Id " .$id. " Account ". $account . " FolderID " . $folderid);
		if ($type != 'addressbook') // || !($contact = $this->addressbook->read($id)))
		{
			debugLog(__METHOD__." Folder wrong or contact not existing");
			return false;
		}
		if ($account == 0)	// as a precausion, we currently do NOT allow to change accounts
		{
			debugLog(__METHOD__." Changing of accounts denied!");
			return false;			//no changing of accounts
		}
		$contact = array();
		if ((empty($id) && ($this->addressbook->grants[$account] & EGW_ACL_EDIT)) || ( $contact = $this->addressbook->read($id) && $this->addressbook->check_perms(EGW_ACL_EDIT, $id)))
		{
			$contact = array();
			foreach (self::$mapping as $key => $attr)
			{
				switch ($attr)
				{
					case 'note':
						$contact[$attr] = $this->backend->messagenote2note($message->body, $message->rtf, $message->airsyncbasebody);
						break;

					case 'bday':	// zpush uses timestamp in servertime
						$contact[$attr] = $message->$key ? date('Y-m-d',$message->$key) : null;
						break;

					case 'jpegphoto':
						$contact[$attr] = base64_decode($message->$key);
						break;

					case 'cat_id':
						if (is_array($message->$key))
						{
							$contact[$attr] = implode(',', array_filter($this->addressbook->find_or_add_categories($message->$key, $id),'strlen'));
						}
						break;

					default:
						$contact[$attr] = $message->$key;
						break;
				}
			}
			// for all-in-one addressbook, account is meaningless and wrong!
			// addressbook_bo::save() keeps the owner or sets an appropriate one if none given
			if (!$GLOBALS['egw_info']['user']['preferences']['activesync']['addressbook-all-in-one'])
			{
				$contact['owner'] = $account;
			}
			if (!empty($id)) $contact['id'] = $id;
			$this->addressbook->fixup_contact($contact);
			$newid = $this->addressbook->save($contact);
error_log(__METHOD__."($folderid,$id) addressbook(".array2string($contact).") returning ".array2string($newid));
			return $this->StatMessage($folderid, $newid);
		}
		return false;
	}

	/**
	 * Moves a message from one folder to another
	 *
	 * @param $folderid of the current folder
	 * @param $id of the message
	 * @param $newfolderid
	 *
	 * @return $newid as a string | boolean false on error
	 *
	 * After this call, StatMessage() and GetMessageList() should show the items
	 * to have a new parent. This means that it will disappear from GetMessageList() will not return the item
	 * at all on the source folder, and the destination folder will show the new message
	 *
	 * @ToDo: If this gets implemented, we have to take into account the 'addressbook-all-in-one' pref!
	 */
	public function MoveMessage($folderid, $id, $newfolderid)
	{
		if ($GLOBALS['egw_info']['user']['preferences']['activesync']['addressbook-all-in-one'])
		{
			debugLog(__METHOD__."('$folderid', $id, $newfolderid) NOT allowed for an all-in-one addressbook --> returning false");
			return false;
		}
		debugLog(__METHOD__."('$folderid', $id, $newfolderid) NOT implemented --> returning false");
		return false;
	}


	/**
	 * Delete (really delete) a message in a folder
	 *
	 * @param $folderid
	 * @param $id
	 *
	 * @return boolean true on success, false on error, diffbackend does NOT use the returnvalue
	 *
	 * @DESC After this call has succeeded, a call to
	 * GetMessageList() should no longer list the message. If it does, the message will be re-sent to the PDA
	 * as it will be seen as a 'new' item. This means that if you don't implement this function, you will
	 * be able to delete messages on the PDA, but as soon as you sync, you'll get the item back
	 */
	public function DeleteMessage($folderid, $id)
	{
		if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();

		$ret = $this->addressbook->delete($id);
		debugLog(__METHOD__."('$folderid', $id) delete($id) returned ".array2string($ret));
		return $ret;
	}

	/**
	 * This should change the 'read' flag of a message on disk. The $flags
	 * parameter can only be '1' (read) or '0' (unread). After a call to
	 * SetReadFlag(), GetMessageList() should return the message with the
	 * new 'flags' but should not modify the 'mod' parameter. If you do
	 * change 'mod', simply setting the message to 'read' on the PDA will trigger
	 * a full resync of the item from the server
	 */
	function SetReadFlag($folderid, $id, $flags)
	{
		return false;
	}

	/**
	 * Return a changes array
	 *
	 * if changes occurr default diff engine computes the actual changes
	 *
	 * @param string $folderid
	 * @param string &$syncstate on call old syncstate, on return new syncstate
	 * @return array|boolean false if $folderid not found, array() if no changes or array(array("type" => "fakeChange"))
	 */
	function AlterPingChanges($folderid, &$syncstate)
	{
		$this->backend->splitID($folderid, $type, $owner);

		if ($type != 'addressbook') return false;

		if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();
		$ctag = $this->addressbook->get_ctag($owner);

		$changes = array();	// no change
		$syncstate_was = $syncstate;

		if ($ctag !== $syncstate)
		{
			$syncstate = $ctag;
			$changes = array(array('type' => 'fakeChange'));
		}
		//error_log(__METHOD__."('$folderid','$syncstate_was') syncstate='$syncstate' returning ".array2string($changes));
		return $changes;
	}

	/**
	 * Search global address list for a given pattern
	 *
	 * @param string $searchquery
	 * @return array with just rows (no values for keys rows, status or global_search_status!)
	 * @todo search range not verified, limits might be a good idea
	 */
	function getSearchResultsGAL($searchquery)
	{
		if (!isset($this->addressbook)) $this->addressbook = new addressbook_bo();

		$items = array();
		if (($contacts =& $this->addressbook->search($searchquery, false, false, '', '%', false, 'OR')))
		{
			foreach($contacts as $contact)
			{
			  	$item['username'] = $contact['n_family'];
				$item['fullname'] = $contact['n_fn'];
				if (!trim($item['fullname'])) $item['fullname'] = $item['username'];
				$item['emailaddress'] = $contact['email'] ? $contact['email'] : (string)$contact['email_private'] ;
				$item['nameid'] = $searchquery;
				$item['phone'] = (string)$contact['tel_work'];
				$item['homephone'] = (string)$contact['tel_home'];
				$item['mobilephone'] = (string)$contact['tel_cell'];
				$item['company'] = (string)$contact['org_name'];
				$item['office'] = $contact['room'];
				$item['title'] = $contact['title'];

			  	//do not return users without email
				if (!trim($item['emailaddress'])) continue;

				$items[] = $item;
			}
		}
		return $items;
	}

	/**
	 * Populates $settings for the preferences
	 *
	 * @param array|string $hook_data
	 * @return array
	 */
	function settings($hook_data)
	{
		$addressbooks = array();

		if (!isset($hook_data['setup']))
		{
			$user = $GLOBALS['egw_info']['user']['account_id'];
			$addressbook_bo = new addressbook_bo();
			$addressbooks = $addressbook_bo->get_addressbooks(EGW_ACL_READ);
			unset($addressbooks[$user]);	// personal addressbook is allways synced
			unset($addressbooks[$user.'p']);// private addressbook uses ID self::PRIVATE_AB
		}
		if ($GLOBALS['egw_info']['user']['preferences']['addressbook']['private_addressbook'])
		{
			$addressbooks[self::PRIVATE_AB] = lang('Private');
		}
		$addressbooks += array(
			'G'	=> lang('Primary Group'),
			'U' => lang('Accounts'),
			'A'	=> lang('All'),
		);
		// allow to force "none", to not show the prefs to the users
		if ($GLOBALS['type'] == 'forced')
		{
			$addressbooks['N'] = lang('None');
		}

		// rewriting owner=0 to 'U', as 0 get's always selected by prefs
		if (!isset($addressbooks[0]))
		{
			unset($addressbooks['U']);
		}
		else
		{
			unset($addressbooks[0]);
		}

		$settings['addressbook-abs'] = array(
			'type'   => 'multiselect',
			'label'  => 'Addressbooks to sync',
			'name'   => 'addressbook-abs',
			'help'   => 'Global address search always searches in all addressbooks, so you dont need to sync all addressbooks to be able to access them, if you are online.',
			'values' => $addressbooks,
			'xmlrpc' => True,
			'admin'  => False,
		);

		$settings['addressbook-all-in-user'] = array(
			'type'   => 'check',
			'label'  => 'Sync all addressbooks as one',
			'name'   => 'addressbook-all-in-one',
			'help'   => 'Not all devices support multiple addressbooks, so you can choose to sync all above selected addressbooks as one.',
			'xmlrpc' => true,
			'admin'  => false,
			'default' => '0',
		);
		return $settings;
	}
}