<?php
/**
 * A general hub node class
 *
 * @author		Roland Haeder <webmaster@ship-simu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 Hub Developer Team
 * @license		GNU GPL 3.0 or any newer version
 * @link		http://www.ship-simu.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 BaseHubNode extends BaseHubSystem implements Updateable {
	/**
	 * Node id
	 */
	private $nodeId = '';

	/**
	 * Session id
	 */
	private $sessionId = '';

	/**
	 * IP/port number of bootstrapping node
	 */
	private $bootIpPort = '';

	/**
	 * Query connector instance
	 */
	private $queryInstance = null;

	/**
	 * Listener pool instance
	 */
	private $listenerPoolInstance = null;

	/**
	 * Wether the hub is active (true/false)
	 */
	private $hubIsActive = false;

	/**
	 * Protected constructor
	 *
	 * @param	$className	Name of the class
	 * @return	void
	 */
	protected function __construct ($className) {
		// Call parent constructor
		parent::__construct($className);
	}

	/**
	 * Setter for node id
	 *
	 * @param	$nodeId		Our new node id
	 * @return	void
	 */
	private final function setNodeId ($nodeId) {
		$this->nodeId = (string) $nodeId;
	}

	/**
	 * Getter for node id
	 *
	 * @return	$nodeId		Our new node id
	 */
	private final function getNodeId () {
		return $this->nodeId;
	}

	/**
	 * Setter for listener pool instance
	 *
	 * @param	$listenerPoolInstance	Our new listener pool instance
	 * @return	void
	 */
	private final function setListenerPoolInstance (PoolableListener $listenerPoolInstance) {
		$this->listenerPoolInstance = $listenerPoolInstance;
	}

	/**
	 * Getter for listener pool instance
	 *
	 * @return	$listenerPoolInstance	Our current listener pool instance
	 */
	public final function getListenerPoolInstance () {
		return $this->listenerPoolInstance;
	}

	/**
	 * Setter for session id
	 *
	 * @param	$sessionId		Our new session id
	 * @return	void
	 */
	private final function setSessionId ($sessionId) {
		$this->sessionId = (string) $sessionId;
	}

	/**
	 * Getter for session id
	 *
	 * @return	$sessionId		Our new session id
	 */
	public final function getSessionId () {
		return $this->sessionId;
	}

	/**
	 * Setter for query instance
	 *
	 * @param	$queryInstance		Our new query instance
	 * @return	void
	 */
	private final function setQueryInstance (Queryable $queryInstance) {
		$this->queryInstance = $queryInstance;
	}

	/**
	 * Getter for query instance
	 *
	 * @return	$queryInstance		Our new query instance
	 */
	public final function getQueryInstance () {
		return $this->queryInstance;
	}

	/**
	 * Getter for boot IP/port combination
	 *
	 * @return	$bootIpPort		The IP/port combination of the boot node
	 */
	protected final function getBootIpPort () {
		return $this->bootIpPort;
	}

	/**
	 * Checks wether the given IP address matches one of the bootstrapping nodes
	 *
	 * @param	$remoteAddr		IP address to checkout against our bootstrapping list
	 * @return	$isFound		Wether the IP is found
	 */
	protected function ifAddressMatchesBootstrappingNodes ($remoteAddr) {
		// By default nothing is found
		$isFound = false;

		// Run through all configured IPs
		foreach (explode(',', $this->getConfigInstance()->getConfigEntry('hub_bootstrap_nodes')) as $ipPort) {
			// Split it up in IP/port
			$ipPortArray = explode(':', $ipPort);

			// Does it match?
			if ($ipPortArray[0] == $remoteAddr) {
				// Found it!
				$isFound = true;

				// Remember the port number
				$this->bootIpPort = $ipPort;

				// Output message
				$this->debugOutput('BOOTSTRAP: ' . __FUNCTION__ . '[' . __LINE__ . ']: IP matches remote address ' . $ipPort . '.');

				// Stop further searching
				break;
			} elseif ($ipPortArray[0] == $this->getConfigInstance()->getConfigEntry('node_listen_addr')) {
				// IP matches listen address. At this point we really don't care
				// if we can also listen on that address!
				$isFound = true;

				// Remember the port number
				$this->bootIpPort = $ipPort;

				// Output message
				$this->debugOutput('BOOTSTRAP: ' . __FUNCTION__ . '[' . __LINE__ . ']: IP matches listen address ' . $ipPort . '.');

				// Stop further searching
				break;
			}
		} // END - foreach

		// Return the result
		return $isFound;
	}

	/**
	 * Outputs the console teaser. This should only be executed on startup or
	 * full restarts. This method generates some space around the teaser.
	 *
	 * @return	void
	 */
	public function outputConsoleTeaser () {
		// Get the app instance (for shortening our code)
		$app = $this->getApplicationInstance();

		// Output all lines
		$this->debugOutput(' ');
		$this->debugOutput($app->getAppName() . ' v' . $app->getAppVersion() . ' - ' . $this->getRequestInstance()->getRequestElement('mode') . ' mode active');
		$this->debugOutput('Copyright (c) 2007 - 2008 Roland Haeder, 2009 Hub Developer Team');
		$this->debugOutput(' ');
		$this->debugOutput('This program comes with ABSOLUTELY NO WARRANTY; for details see docs/COPYING.');
		$this->debugOutput('This is free software, and you are welcome to redistribute it under certain');
		$this->debugOutput('conditions; see docs/COPYING for details.');
		$this->debugOutput(' ');
	}

	/**
	 * Generic method to acquire a hub-id. On first run this generates a new one
	 * based on many pseudo-random data. On any later run, unless the id
	 * got not removed from database, it will be restored from the database.
	 *
	 * @return	void
	 */
	public function bootstrapAcquireHubId () {
		// Get a wrapper instance
		$wrapperInstance = ObjectFactory::createObjectByConfiguredName('node_info_db_wrapper_class');

		// Now get a search criteria instance
		$searchInstance = ObjectFactory::createObjectByConfiguredName('search_criteria_class');

		// Search for the node number zero which is hard-coded the default
		$searchInstance->addCriteria(NodeInformationDatabaseWrapper::DB_COLUMN_NODE_NR, 1);
		$searchInstance->addCriteria(NodeInformationDatabaseWrapper::DB_COLUMN_NODE_TYPE, $this->getRequestInstance()->getRequestElement('mode'));
		$searchInstance->setLimit(1);

		// Get a result back
		$resultInstance = $wrapperInstance->doSelectByCriteria($searchInstance);

		// Is it valid?
		if ($resultInstance->next()) {
			// Save the result instance in this class
			$this->setResultInstance($resultInstance);

			// Get the node id from result and set it
			$this->setNodeId($this->getField(NodeInformationDatabaseWrapper::DB_COLUMN_NODE_ID));

			// Output message
			$this->debugOutput('BOOTSTRAP: Re-using found node-id: ' . $this->getNodeId() . '');
		} else {
			// Get an RNG instance (Random Number Generator)
			$rngInstance = ObjectFactory::createObjectByConfiguredName('rng_class');

			// Generate a pseudo-random string
			$randomString = $rngInstance->randomString(255) . ':' . $this->getBootIpPort()  . ':' . $this->getRequestInstance()->getRequestElement('mode');

			// Get a crypto instance
			$cryptoInstance = ObjectFactory::createObjectByConfiguredName('crypto_class');

			// Hash and encrypt the string so we become a "node id" aka Hub-Id
			$this->setNodeId($cryptoInstance->hashString($cryptoInstance->encryptString($randomString)));

			// Register the node id with our wrapper
			$wrapperInstance->registerNodeId($this, $this->getRequestInstance());

			// Output message
			$this->debugOutput('BOOTSTRAP: Created new node-id: ' . $this->getNodeId() . '');
		}
	}

	/**
	 * Generates a session id which will be sent to the other hubs and clients
	 *
	 * @return	void
	 */
	public function bootstrapGenerateSessionId () {
		// Get an RNG instance
		$rngInstance = ObjectFactory::createObjectByConfiguredName('rng_class');

		// Generate a pseudo-random string
		$randomString = $rngInstance->randomString(255) . ':' . $this->getBootIpPort() . ':' . $this->getRequestInstance()->getRequestElement('mode');

		// Get a crypto instance
		$cryptoInstance = ObjectFactory::createObjectByConfiguredName('crypto_class');

		// Hash and encrypt the string so we become a "node id" aka Hub-Id
		$this->setSessionId($cryptoInstance->hashString($cryptoInstance->encryptString($randomString)));

		// Get a wrapper instance
		$wrapperInstance = ObjectFactory::createObjectByConfiguredName('node_info_db_wrapper_class');

		// Register the node id with our wrapper
		$wrapperInstance->registerSessionId($this, $this->getRequestInstance());

		// Output message
		$this->debugOutput('BOOTSTRAP: Created new session-id: ' . $this->getSessionId() . '');
	}

	/**
	 * Initializes queues which every node needs
	 *
	 * @return	void
	 */
	protected function initGenericQueues () {
		// Debug message
		$this->debugOutput('BOOTSTRAP: Initialize queues: START');

		// Set the query connector instance
		$this->setQueryInstance(ObjectFactory::createObjectByConfiguredName('query_connector_class', array($this)));

		// Run a test query
		$this->getQueryInstance()->doTestQuery();

		// Debug message
		$this->debugOutput('BOOTSTRAP: Initialize queues: FINISHED');
	}
	
	/**
	 * Adds hub data elements to a given dataset instance
	 *
	 * @param	$criteriaInstance	An instance of a storeable criteria
	 * @param	$requestInstance	An instance of a Requestable class
	 * @return	void
	 */
	public function addElementsToDataSet (StoreableCriteria $criteriaInstance, Requestable $requestInstance) {
		// Add node number and type
		$criteriaInstance->addCriteria(NodeInformationDatabaseWrapper::DB_COLUMN_NODE_NR, 1);
		$criteriaInstance->addCriteria(NodeInformationDatabaseWrapper::DB_COLUMN_NODE_TYPE, $requestInstance->getRequestElement('mode'));

		// Add the node id
		$criteriaInstance->addCriteria(NodeInformationDatabaseWrapper::DB_COLUMN_NODE_ID, $this->getNodeId());

		// Add the session id if acquired
		if ($this->getSessionId() != '') {
			$criteriaInstance->addCriteria(NodeInformationDatabaseWrapper::DB_COLUMN_SESSION_ID, $this->getSessionId());
		} // END - if
	}

	/**
	 * Updates a given field with new value
	 *
	 * @param	$fieldName		Field to update
	 * @param	$fieldValue		New value to store
	 * @return	void
	 * @throws	DatabaseUpdateSupportException	If this class does not support database updates
	 * @todo	Try to make this method more generic so we can move it in BaseFrameworkSystem
	 */
	public function updateDatabaseField ($fieldName, $fieldValue) {
		// Unfinished
		$this->partialStub('Unfinished!');
		return;

		// Get a critieria instance
		$searchInstance = ObjectFactory::createObjectByConfiguredName('search_criteria_class');

		// Add search criteria
		$searchInstance->addCriteria(UserDatabaseWrapper::DB_COLUMN_USERNAME, $this->getUserName());
		$searchInstance->setLimit(1);

		// Now get another criteria
		$updateInstance = ObjectFactory::createObjectByConfiguredName('update_criteria_class');

		// Add criteria entry which we shall update
		$updateInstance->addCriteria($fieldName, $fieldValue);

		// Add the search criteria for searching for the right entry
		$updateInstance->setSearchInstance($searchInstance);

		// Set wrapper class name
		$updateInstance->setWrapperConfigEntry('user_db_wrapper_class');

		// Remember the update in database result
		$this->getResultInstance()->add2UpdateQueue($updateInstance);
	}

	/**
	 * Getter for $hubIsActive attribute
	 *
	 * @return	$hubIsActive	Wether the hub is activer
	 */
	public final function isHubActive () {
		return $this->hubIsActive;
	}

	/**
	 * Setter for $hubIsActive attribute
	 *
	 * @param	$hubIsActive	Wether the hub is activer
	 */
	public final function enableHubIsActive ($hubIsActive = true) {
		$this->hubIsActive = $hubIsActive;
	}

	/**
	 * Activates the hub by doing some final preparation and setting
	 * $hubIsActive to true
	 *
	 * @param	$requestInstance	A Requestable class
	 * @param	$responseInstance	A Responseable class
	 * @return	void
	 */
	public function activateHub (Requestable $requestInstance, Responseable $responseInstance) {
		// Checks wether a listener is still active and shuts it down if one
		// is still listening
		if (($this->determineIfListenerIsActive()) && ($this->isHubActive())) {
			// Shutdown them down before they can hurt anything
			$this->shutdownListenerPool();
		} // END - if

		// Get the controller here
		$controllerInstance = Registry::getRegistry()->getInstance('controller');

		// Run all filters for the hub activation
		$controllerInstance->executeActivationFilters($requestInstance, $responseInstance);

		// ----------------------- Last step from here ------------------------
		// Activate the hub. This is ALWAYS the last step in this method
		$this->enableHubIsActive();
		// ---------------------- Last step until here ------------------------
	}

	/**
	 * Initializes the listener pool (class)
	 *
	 * @return	void
	 */
	public function initializeListenerPool () {
		// Debug output
		$this->debugOutput('HUB: Initialize listener: START');

		// Get a new pool instance
		$this->setListenerPoolInstance(ObjectFactory::createObjectByConfiguredName('listener_pool_class', array($this)));

		// Get an instance of the low-level listener
		$listenerInstance = ObjectFactory::createObjectByConfiguredName('tcp_listener_class', array($this));

		// Setup address and port
		$listenerInstance->setListenAddressByConfiguration('node_listen_addr');
		$listenerInstance->setListenPortByConfiguration('node_tcp_listen_port');

		// Initialize the listener
		$listenerInstance->initListener();

		// Get a decorator class
		$decoratorInstance = ObjectFactory::createObjectByConfiguredName('hub_tcp_listener_class', array($listenerInstance));

		// Add this listener to the pool
		$this->getListenerPoolInstance()->addListener($decoratorInstance);

		// Get a decorator class
		$decoratorInstance = ObjectFactory::createObjectByConfiguredName('client_tcp_listener_class', array($listenerInstance));

		// Add this listener to the pool
		$this->getListenerPoolInstance()->addListener($decoratorInstance);

		// Get an instance of the low-level listener
		$listenerInstance = ObjectFactory::createObjectByConfiguredName('udp_listener_class', array($this));

		// Setup address and port
		$listenerInstance->setListenAddressByConfiguration('node_listen_addr');
		$listenerInstance->setListenPortByConfiguration('node_udp_listen_port');

		// Initialize the listener
		$listenerInstance->initListener();

		// Get a decorator class
		$decoratorInstance = ObjectFactory::createObjectByConfiguredName('hub_udp_listener_class', array($listenerInstance));

		// Add this listener to the pool
		$this->getListenerPoolInstance()->addListener($decoratorInstance);

		// Get a decorator class
		$decoratorInstance = ObjectFactory::createObjectByConfiguredName('client_udp_listener_class', array($listenerInstance));

		// Add this listener to the pool
		$this->getListenerPoolInstance()->addListener($decoratorInstance);

		// Debug output
		$this->debugOutput('HUB: Initialize listener: FINISHED.');
	}

	/**
	 * Restores a previously stored node list from database
	 *
	 * @return	void
	 */
	public function bootstrapRestoreNodeList () {
		// Debug output
		$this->debugOutput('HUB: Restore node list: START');

		// Get a wrapper instance
		$wrapperInstance = ObjectFactory::createObjectByConfiguredName('node_list_db_wrapper_class');

		// Now get a search criteria instance
		$searchInstance = ObjectFactory::createObjectByConfiguredName('search_criteria_class');

		// Search for the node number zero which is hard-coded the default
		// @TODO Add some criteria, e.g. if the node is active or so
		//$searchInstance->addCriteria(NodeListDatabaseWrapper::DB_COLUMN_NODE_NR, 1);
		//$searchInstance->addCriteria(NodeListDatabaseWrapper::DB_COLUMN_NODE_TYPE, $this->getRequestInstance()->getRequestElement('mode'));
		//$searchInstance->setLimit(1);

		// Get a result back
		$resultInstance = $wrapperInstance->doSelectByCriteria($searchInstance);

		// Is it valid?
		if ($resultInstance->next()) {
			$this->partialStub('Do something for restoring the list.');
			// Output message
			//$this->debugOutput('BOOTSTRAP: ');
		} // END - if

		// Debug output
		$this->debugOutput('HUB: Restore node list: FINISHED.');
	}
}

// [EOF]
?>