<?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 = '';

	/**
	 * 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;
	}

	/**
	 * 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()->readConfig('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->getDebugInstance()->output(__FUNCTION__.'['.__LINE__.']: IP matches remote address ' . $ipPort . '.');

				// Stop further searching
				break;
			} elseif ($ipPortArray[0] == $this->getConfigInstance()->readConfig('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->getDebugInstance()->output(__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->getDebugInstance()->output(' ');
		$this->getDebugInstance()->output($app->getAppName() . ' v' . $app->getAppVersion() . ' - ' . $this->getRequestInstance()->getRequestElement('mode') . ' mode active');
		$this->getDebugInstance()->output('Copyright (c) 2007 - 2008 Roland Haeder, 2009 Hub Developer Team');
		$this->getDebugInstance()->output(' ');
		$this->getDebugInstance()->output('This program comes with ABSOLUTELY NO WARRANTY; for details see docs/COPYING.');
		$this->getDebugInstance()->output('This is free software, and you are welcome to redistribute it under certain');
		$this->getDebugInstance()->output('conditions; see docs/COPYING for details.');
		$this->getDebugInstance()->output(' ');
	}

	/**
	 * Do generic things for bootup phase. This can be e.g. checking if the
	 * right node mode is selected for this hub's IP number.
	 *
	 * @return	void
	 * @todo	This method is maybe not yet finished.
	 */
	protected function doGenericBootstrapping () {
		// --------------------- Hub-id acquirement phase ---------------------
		// Acquire a hub-id. This step generates on first launch a new one and
		// on any later launches it will restore the hub-id from the database.
		// A passed 'nickname=xxx' argument will be used to add some
		// 'personality' to the hub.
		$this->bootstrapAcquireHubId();

		// ------------------- More generic bootstrap steps -------------------
		// Generate the session id which will only be stored in RAM and kept for
		// the whole "session".
		$this->bootstrapGenerateSessionId();

		// Restore a previously downloaded bootstrap-node list.
		$this->bootstrapRestoreNodeList();

		// @TODO Add some generic bootstrap steps
		$this->partialStub('Add some generic bootstrap steps here.');
	}

	/**
	 * 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
	 */
	private 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->getDebugInstance()->output('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->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->getDebugInstance()->output('BOOTSTRAP: Created new node-id: ' . $this->getNodeId() . '');
		}
	}

	/**
	 * Initializes queues which every node needs
	 *
	 * @return	void
	 */
	protected function initGenericQueues () {
		// Set it
		$this->queryInstance = ObjectFactory::createObjectByConfiguredName('query_connector_class', array($this));
	}
	
	/**
	 * 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());
	}

	/**
	 * 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;
	}

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

		// Initialize the TCP/UDP listener pool
		$this->initializeListenerPool();

		// @TODO Do some final preparation
		$this->partialStub('Do some final preparation before the hub gots activated.');

		// ----------------------- Last step from here ------------------------
		// Activate the hub. This is ALWAYS the last step in this method
		$this->hubIsActive = true;
		// ---------------------- Last step until here ------------------------
	}

	/**
	 * Initializes the listener pool (class)
	 *
	 * @return	void
	 */
	private function initializeListenerPool () {
		// Get a new pool instance
		$this->listenerPoolInstance = ObjectFactory::createObjectByConfiguredName('listener_pool_class', array($this));

		// Initialize the TCP 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();

		// Add this listener to the pool
		$this->listenerPoolInstance->addListener($listenerInstance);

		// Initialize the UDP 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();

		// Add this listener to the pool
		$this->listenerPoolInstance->addListener($listenerInstance);
	}
}

// [EOF]
?>