<?php
/**
 * A factory class for peer states
 *
 * @author		Roland Haeder <webmaster@shipsimu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2012 Hub Developer Team
 * @license		GNU GPL 3.0 or any newer version
 * @link		http://www.shipsimu.org
 *
 * 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 PeerStateFactory extends ObjectFactory {
	/**
	 * Static lookup table instance
	 */
	private static $tableInstance = NULL;

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

	/**
	 * Singleton getter for lookup table instances, kept public if we need this
	 * table somewhere else.
	 *
	 * @return	$tableInstance	An instance of a lookup table
	 */
	public static final function getTableInstance () {
		// Is the instance null?
		if (is_null(self::$tableInstance)) {
			// Get a new one
			self::$tableInstance = self::createObjectByConfiguredName('peer_state_lookup_db_wrapper_class');
		} // END - if

		// Return it
		return self::$tableInstance;
	}

	/**
	 * Creates a peer state instance based on errorCode if no entry is found in the lookup table
	 * for the peer given in $packageData 'sender' element or it changes the state if it differs
	 * from current state.
	 *
	 * @param	$helperInstance		An instance of a ConnectionHelper class
	 * @param	$packageData		Raw package data
	 * @param	$socketResource		A valid socket resource
	 * @param	$errorCode			The last error code
	 * @return	$stateInstance		A Stateable class instance
	 */
	public static final function createPeerStateInstanceBySocketStatusCode (ConnectionHelper $helperInstance, array $packageData, $socketResource, $errorCode) {
		// Init state instance, this is better coding practice
		$stateInstance = NULL;

		// So first we need our lookup table
		$tableInstance = self::getTableInstance();

		/*
		 * Now try to purge old entries before looking an entry up. This shall
		 * make it sure that only accurate entries can be found.
		 */
		try {
			// Purge old entries
			$tableInstance->purgeOldEntriesBySocketResource($socketResource);
		} catch (InvalidSocketException $e) {
			// Just log all errors
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PEER-STATE-FACTORY[' . __LINE__ . ':] Purging of old entries failed. Message from exception: ' . $e->getMessage());
		}

		// Do we have an entry?
		if ($tableInstance->isSenderNewPeer($packageData)) {
			// Debug output
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PEER-STATE-FACTORY[' . __LINE__ . ':] errorCode=' . $errorCode);

			// Register the new peer with its session id
			$tableInstance->registerPeerByPackageData($packageData, $socketResource);

			/*
			 * It is a new peer so create the state instance based on error
			 * code and get an instance from it.
			 */
			$stateInstance = self::createObjectByConfiguredName('peer_' . $errorCode . '_state_class');

			// And register it with the lookup table
			$tableInstance->registerPeerState($stateInstance, $packageData);
		} elseif ($tableInstance->isSamePeerState($helperInstance, $packageData)) {
			// Debug output
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PEER-STATE-FACTORY[' . __LINE__ . ':] Peer state unchanged, re-generating old state ...');

			/*
			 * The peer's state has noot changed, still we have to return a
			 * state instance, so generate it here.
			 */
			$stateInstance = self::createPeerStateInstanceByName($helperInstance->getPrintableState(), $helperInstance);
		} else {
			// Debug output
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PEER-STATE-FACTORY[' . __LINE__ . ':] Updating peer state ...');

			/*
			 * It is an already known peer but with a changed state. So first
			 * get an instance of the state.
			 */
			$stateInstance = self::createObjectByConfiguredName('peer_' . $errorCode . '_state_class');

			// The peer's state has changed, update database now
			$tableInstance->registerPeerState($stateInstance, $packageData);
		}

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PEER-STATE-FACTORY[' . __LINE__ . ':] Peer state has changed from ' . $helperInstance->getPrintableState() . ' to ' . $stateInstance->getStateName() . ' (' . $stateInstance->__toString() . ').');

		// Set the state in the helper
		$helperInstance->setStateInstance($stateInstance);

		// For any purposes, return the state instance
		return $stateInstance;
	}

	/**
	 * Creates an instance of a configurable peer state and sets it in the
	 * given peer instance.
	 *
	 * @param	$stateName			Name of the state
	 * @param	$helperInstance		A ConnectionHelper class instance
	 * @return	$stateInstance		A Stateable class instance
	 */
	public static final function createPeerStateInstanceByName ($stateName, ConnectionHelper $helperInstance) {
		// Get a class from a configuration entry
		$stateInstance = self::createObjectByConfiguredName('peer_' . $stateName . '_state_class', array($helperInstance));

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PEER-STATE-FACTORY[' . __LINE__ . ':] Peer state has changed from ' . $helperInstance->getPrintableState() . ' to ' . $stateInstance->getStateName() . ' (' . $stateInstance->__toString() . ').');

		// Once we have that state, set it in the peer instance
		$helperInstance->setStateInstance($stateInstance);

		// For any purposes, return the state instance
		return $stateInstance;
	}
}

// [EOF]
?>