<?php
/**
 * A helper for Ship-Simu to login. This login helper first checks what setting
 * (cookie or session) the admin has choosen then overwrites it with the setting
 * from current user. The registry instance should hold an instance of this user
 * class at key 'user' else an exception will be thrown. After this the setting
 * from a login form will be taken as login method and be stored in database
 * for later usage.
 *
 * The user shall be able to choose "Default login method" or similar to use his
 * own login method.
 *
 * @author		Roland Haeder <webmaster@ship-simu.org>
 * @version		0.0.0
 * @copyright	Copyright(c) 2007, 2008 Roland Haeder, this is free software
 * @license		GNU GPL 3.0 or any newer version
 * @link		http://www.ship-simu.org
 * @todo		Find an interface name for login helper
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
class ShipSimuLoginHelper extends BaseLoginHelper {
	// Exception constants
	const EXCEPTION_INVALID_USER_INSTANCE = 0xf00;

	/**
	 * Protected constructor
	 *
	 * @return	void
	 */
	protected function __construct () {
		// Call parent constructor
		parent::__construct(__CLASS__);

		// Set part description
		$this->setObjectDescription("Login helper for Ship-Simu");

		// Create unique ID number
		$this->generateUniqueId();
	}

	/**
	 * Creates an instance of this class by given request instance
	 *
	 * @param	$requestInstance	An instance of a Requestable class
	 * @return	$helperInstance		An instance of this helper class
	 * @throws	UserInstanceMissingException	If the user instance in registry
	 *											is missing or invalid
	 */
	public final static function createShipSimuLoginHelper (Requestable $requestInstance) {
		// Get a new instance first
		$helperInstance = new ShipSimuLoginHelper();

		// Get a user instance from registry
		$userInstance = Registry::getRegistry()->getInstance('user');

		// Is this instance valid?
		if (!$userInstance instanceof ManageableUser) {
			// Thrown an exception here
			throw new UserInstanceMissingException (array($helperInstance, 'user'), self::EXCEPTION_INVALID_USER_INSTANCE);
		} // END - if

		// Get the login method from request
		$methodRequest = $requestInstance->getRequestElement('login_method');

		// Now, if that wents fine we can check if the request includes a login method entry
		if ((!is_null($methodRequest)) && ($methodRequest != "default") && ($methodRequest != $userInstance->getLoginMethod())) {
			// Okay, the login method has been choosen by user so remember it
			$helperInstance->setLoginMethod($methodRequest);

			// Remeber that we need to update the user account as well
			$userInstance->addUpdateData('login_method', $methodRequest);
		} elseif (($methodRequest == "default") && (is_string($userInstance->getLoginMethod()))) {
			// Choose default method from user
			$helperInstance->setLoginMethod($userInstance->getLoginMethod());
		} else {
			// Set default login method from config
			$helperInstance->setDefaultLoginMethod();
		}
		
		// Return the prepared instance
		return $helperInstance;
	}
}

// [EOF]
?>