<?php
/**
 * A NetworkPackage class. This class implements Deliverable and Receivable
 * because all network packages should be deliverable to other nodes and
 * receivable from other nodes. It further provides methods for reading raw
 * content from template engines and feeding it to the stacker for undeclared
 * packages.
 *
 * The factory method requires you to provide a compressor class (which must
 * implement the Compressor interface). If you don't want any compression (not
 * adviceable due to increased network load), please use the NullCompressor
 * class and encode it with BASE64 for a more error-free transfer over the
 * Internet.
 *
 * For performance reasons, this class should only be instanciated once and then
 * used as a "pipe-through" class.
 *
 * @author		Roland Haeder <webmaster@shipsimu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 Hub Developer Team
 * @license		GNU GPL 3.0 or any newer version
 * @link		http://www.shipsimu.org
 * @todo		Needs to add functionality for handling the object's type
 *
 * 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 NetworkPackage extends BaseHubSystem implements Deliverable, Receivable, Registerable, Visitable {
	/**
	 * Package mask for compressing package data:
	 * 0: Compressor extension
	 * 1: Raw package data
	 * 2: Tags, seperated by semicolons, no semicolon is required if only one tag is needed
	 * 3: Checksum
	 *                     0  1  2  3
	 */
	const PACKAGE_MASK = '%s%s%s%s%s%s%s';

	/**
	 * Separator for the above mask
	 */
	const PACKAGE_MASK_SEPARATOR = '^';

	/**
	 * Size of an array created by invoking
	 * explode(NetworkPackage::PACKAGE_MASK_SEPARATOR, $content).
	 */
	const PACKAGE_CONTENT_ARRAY_SIZE = 4;

	/**
	 * Separator for checksum
	 */
	const PACKAGE_CHECKSUM_SEPARATOR = '_';

	/**
	 * Array indexes for above mask, start with zero
	 */
	const INDEX_COMPRESSOR_EXTENSION = 0;
	const INDEX_PACKAGE_DATA         = 1;
	const INDEX_TAGS                 = 2;
	const INDEX_CHECKSUM             = 3;

	/**
	 * Array indexes for raw package array
	 */
	const INDEX_PACKAGE_SENDER           = 0;
	const INDEX_PACKAGE_RECIPIENT        = 1;
	const INDEX_PACKAGE_CONTENT          = 2;
	const INDEX_PACKAGE_STATUS           = 3;
	const INDEX_PACKAGE_HASH             = 4;
	const INDEX_PACKAGE_PRIVATE_KEY_HASH = 5;

	/**
	 * Size of the decoded data array
	 */
	const DECODED_DATA_ARRAY_SIZE = 6;

	/**
	 * Named array elements for decoded package content
	 */
	const PACKAGE_CONTENT_EXTENSION        = 'compressor';
	const PACKAGE_CONTENT_MESSAGE          = 'message';
	const PACKAGE_CONTENT_TAGS             = 'tags';
	const PACKAGE_CONTENT_CHECKSUM         = 'checksum';
	const PACKAGE_CONTENT_SENDER           = 'sender';
	const PACKAGE_CONTENT_HASH             = 'hash';
	const PACKAGE_CONTENT_PRIVATE_KEY_HASH = 'pkhash';

	/**
	 * Named array elements for package data
	 */
	const PACKAGE_DATA_SENDER           = 'sender';
	const PACKAGE_DATA_RECIPIENT        = 'recipient';
	const PACKAGE_DATA_CONTENT          = 'content';
	const PACKAGE_DATA_STATUS           = 'status';
	const PACKAGE_DATA_HASH             = 'hash';
	const PACKAGE_DATA_PRIVATE_KEY_HASH = 'pkhash';

	/**
	 * All package status
	 */
	const PACKAGE_STATUS_NEW     = 'new';
	const PACKAGE_STATUS_FAILED  = 'failed';
	const PACKAGE_STATUS_DECODED = 'decoded';
	const PACKAGE_STATUS_FAKED   = 'faked';

	/**
	 * Constants for message data array
	 */
	const MESSAGE_ARRAY_DATA   = 'message_data';
	const MESSAGE_ARRAY_TYPE   = 'message_type';
	const MESSAGE_ARRAY_SENDER = 'message_sender';
	const MESSAGE_ARRAY_HASH   = 'message_hash';
	const MESSAGE_ARRAY_TAGS   = 'message_tags';

	/**
	 * Generic answer status field
	 */

	/**
	 * Tags separator
	 */
	const PACKAGE_TAGS_SEPARATOR = ';';

	/**
	 * Raw package data separator
	 */
	const PACKAGE_DATA_SEPARATOR = '#';

	/**
	 * Separator for more than one recipient
	 */
	const PACKAGE_RECIPIENT_SEPARATOR = ':';

	/**
	 * Network target (alias): 'upper nodes'
	 */
	const NETWORK_TARGET_UPPER = 'upper';

	/**
	 * Network target (alias): 'self'
	 */
	const NETWORK_TARGET_SELF = 'self';

	/**
	 * Network target (alias): 'dht'
	 */
	const NETWORK_TARGET_DHT = 'dht';

	/**
	 * TCP package size in bytes
	 */
	const TCP_PACKAGE_SIZE = 512;

	/**************************************************************************
	 *                    Stacker for out-going packages                      *
	 **************************************************************************/

	/**
	 * Stacker name for "undeclared" packages
	 */
	const STACKER_NAME_UNDECLARED = 'package_undeclared';

	/**
	 * Stacker name for "declared" packages (which are ready to send out)
	 */
	const STACKER_NAME_DECLARED = 'package_declared';

	/**
	 * Stacker name for "out-going" packages
	 */
	const STACKER_NAME_OUTGOING = 'package_outgoing';

	/**************************************************************************
	 *                     Stacker for incoming packages                      *
	 **************************************************************************/

	/**
	 * Stacker name for "incoming" decoded raw data
	 */
	const STACKER_NAME_DECODED_INCOMING = 'package_decoded_data';

	/**
	 * Stacker name for handled decoded raw data
	 */
	const STACKER_NAME_DECODED_HANDLED = 'package_handled_decoded';

	/**
	 * Stacker name for "chunked" decoded raw data
	 */
	const STACKER_NAME_DECODED_CHUNKED = 'package_chunked_decoded';

	/**************************************************************************
	 *                     Stacker for incoming messages                      *
	 **************************************************************************/

	/**
	 * Stacker name for new messages
	 */
	const STACKER_NAME_NEW_MESSAGE = 'package_new_message';

	/**
	 * Stacker name for processed messages
	 */
	const STACKER_NAME_PROCESSED_MESSAGE = 'package_processed_message';

	/**************************************************************************
	 *                      Stacker for raw data handling                     *
	 **************************************************************************/

	/**
	 * Stacker for outgoing data stream
	 */
	const STACKER_NAME_OUTGOING_STREAM = 'outgoing_stream';

	/**
	 * Array index for final hash
	 */
	const RAW_FINAL_HASH_INDEX = 'hash';

	/**
	 * Array index for encoded data
	 */
	const RAW_ENCODED_DATA_INDEX = 'data';

	/**
	 * Array index for sent bytes
	 */
	const RAW_SENT_BYTES_INDEX = 'sent';

	/**
	 * Array index for socket resource
	 */
	const RAW_SOCKET_INDEX = 'socket';

	/**
	 * Array index for buffer size
	 */
	const RAW_BUFFER_SIZE_INDEX = 'buffer';

	/**
	 * Array index for diff between buffer and sent bytes
	 */
	const RAW_DIFF_INDEX = 'diff';

	/**************************************************************************
	 *                            Protocol names                              *
	 **************************************************************************/
	const PROTOCOL_TCP = 'TCP';
	const PROTOCOL_UDP = 'UDP';

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

	/**
	 * Creates an instance of this class
	 *
	 * @param	$compressorInstance		A Compressor instance for compressing the content
	 * @return	$packageInstance		An instance of a Deliverable class
	 */
	public static final function createNetworkPackage (Compressor $compressorInstance) {
		// Get new instance
		$packageInstance = new NetworkPackage();

		// Now set the compressor instance
		$packageInstance->setCompressorInstance($compressorInstance);

		/*
		 * We need to initialize a stack here for our packages even for those
		 * which have no recipient address and stamp... ;-) This stacker will
		 * also be used for incoming raw data to handle it.
		 */
		$stackInstance = ObjectFactory::createObjectByConfiguredName('network_package_stacker_class');

		// At last, set it in this class
		$packageInstance->setStackInstance($stackInstance);

		// Init all stacker
		$packageInstance->initStacks();

		// Get a visitor instance for speeding up things and set it
		$visitorInstance = ObjectFactory::createObjectByConfiguredName('node_raw_data_monitor_visitor_class');
		$packageInstance->setVisitorInstance($visitorInstance);

		// Get crypto instance and set it, too
		$cryptoInstance = ObjectFactory::createObjectByConfiguredName('crypto_class');
		$packageInstance->setCryptoInstance($cryptoInstance);

		// Get a singleton package assembler instance from factory and set it here, too
		$assemblerInstance = PackageAssemblerFactory::createAssemblerInstance($packageInstance);
		$packageInstance->setAssemblerInstance($assemblerInstance);

		// Get node instance
		$nodeInstance = NodeObjectFactory::createNodeInstance();

		// Get pool instance from node
		$poolInstance = $nodeInstance->getListenerPoolInstance();

		// And set it here
		$packageInstance->setListenerPoolInstance($poolInstance);

		// Return the prepared instance
		return $packageInstance;
	}

	/**
	 * Initialize all stackers
	 *
	 * @param	$forceReInit	Whether to force reinitialization of all stacks
	 * @return	void
	 */
	protected function initStacks ($forceReInit = FALSE) {
		// Initialize all
		$this->getStackInstance()->initStacks(array(
			self::STACKER_NAME_UNDECLARED,
			self::STACKER_NAME_DECLARED,
			self::STACKER_NAME_OUTGOING,
			self::STACKER_NAME_DECODED_INCOMING,
			self::STACKER_NAME_DECODED_HANDLED,
			self::STACKER_NAME_DECODED_CHUNKED,
			self::STACKER_NAME_NEW_MESSAGE,
			self::STACKER_NAME_PROCESSED_MESSAGE,
			self::STACKER_NAME_OUTGOING_STREAM
		), $forceReInit);
	}

	/**
	 * Determines private key hash from given session id
	 *
	 * @param	$decodedData	Array with decoded data
	 * @return	$hash			Private key's hash
	 */
	private function determineSenderPrivateKeyHash (array $decodedData) {
		// Get DHT instance
		$dhtInstance = DhtObjectFactory::createDhtInstance('node');

		// Ask DHT for session id
		$senderData = $dhtInstance->findNodeLocalBySessionId($decodedData[self::PACKAGE_CONTENT_SENDER]);

		// Is an entry found?
		if (count($senderData) > 0) {
			// Make sure the element 'private_key_hash' is there
			//* NOISY-DEBUG */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: senderData=' . print_r($senderData, TRUE));
			assert(isset($senderData[NodeDistributedHashTableDatabaseWrapper::DB_COLUMN_PRIVATE_KEY_HASH]));

			// Return it
			return $senderData[NodeDistributedHashTableDatabaseWrapper::DB_COLUMN_PRIVATE_KEY_HASH];
		} // END - if

		// Make sure the requested element is there
		//* DEBUG-DIE */ die('decodedData=' . print_r($decodedData, TRUE));
		assert(isset($decodedData[self::PACKAGE_CONTENT_PRIVATE_KEY_HASH]));

		// Don't accept empty keys
		if (empty($decodedData[self::PACKAGE_CONTENT_PRIVATE_KEY_HASH])) {
			// This needs fixing
			die('[' . __METHOD__ . ':' . __LINE__ . ':] Empty private key hash: decodedData=' . print_r($decodedData, TRUE));
		} // END - if

		// There is no DHT entry so, accept the hash from decoded data
		return $decodedData[self::PACKAGE_CONTENT_PRIVATE_KEY_HASH];
	}

	/**
	 * "Getter" for hash from given content
	 *
	 * @param	$content	Raw package content
	 * @return	$hash		Hash for given package content
	 */
	private function getHashFromContent ($content) {
		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: content[md5]=' . md5($content) . ',sender=' . $this->getSessionId() . ',compressor=' . $this->getCompressorInstance()->getCompressorExtension());

		// Create the hash
		// @TODO md5() is very weak, but it needs to be fast
		$hash = md5(
			$content .
			self::PACKAGE_CHECKSUM_SEPARATOR .
			$this->getSessionId() .
			self::PACKAGE_CHECKSUM_SEPARATOR .
			$this->getCompressorInstance()->getCompressorExtension()
		);

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: content[md5]=' . md5($content) . ',sender=' . $this->getSessionId() . ',hash=' . $hash . ',compressor=' . $this->getCompressorInstance()->getCompressorExtension());

		// And return it
		return $hash;
	}

	/**
	 * Checks whether the checksum (sometimes called "hash") is the same
	 *
	 * @param	$decodedContent		Package raw content
	 * @param	$decodedData		Whole raw package data array
	 * @return	$isChecksumValid	Whether the checksum is the same
	 */
	private function isChecksumValid (array $decodedContent, array $decodedData) {
		// Get checksum
		$checksum = $this->getHashFromContentSessionId($decodedContent, $decodedData[self::PACKAGE_DATA_SENDER]);

		// Is it the same?
		$isChecksumValid = ($checksum == $decodedContent[self::PACKAGE_CONTENT_CHECKSUM]);

		// Return it
		return $isChecksumValid;
	}

	/**
	 * Change the package with given status in given stack
	 *
	 * @param	$packageData	Raw package data in an array
	 * @param	$stackerName	Name of the stacker
	 * @param	$newStatus		New status to set
	 * @return	void
	 */
	private function changePackageStatus (array $packageData, $stackerName, $newStatus) {
		// Skip this for empty stacks
		if ($this->getStackInstance()->isStackEmpty($stackerName)) {
			// This avoids an exception after all packages has failed
			return;
		} // END - if

		// Pop the entry (it should be it)
		$nextData = $this->getStackInstance()->popNamed($stackerName);

		// Compare both hashes
		assert($nextData[self::PACKAGE_DATA_HASH] == $packageData[self::PACKAGE_DATA_HASH]);

		// Temporary set the new status
		$packageData[self::PACKAGE_DATA_STATUS] = $newStatus;

		// And push it again
		$this->getStackInstance()->pushNamed($stackerName, $packageData);
	}

	/**
	 * "Getter" for hash from given content and sender's session id
	 *
	 * @param	$decodedContent		Raw package content
	 * @param	$sessionId			Session id of the sender
	 * @return	$hash				Hash for given package content
	 */
	public function getHashFromContentSessionId (array $decodedContent, $sessionId) {
		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: content[md5]=' . md5($decodedContent[self::PACKAGE_CONTENT_MESSAGE]) . ',sender=' . $sessionId . ',compressor=' . $decodedContent[self::PACKAGE_CONTENT_EXTENSION]);

		// Create the hash
		// @TODO md5() is very weak, but it needs to be fast
		$hash = md5(
			$decodedContent[self::PACKAGE_CONTENT_MESSAGE] .
			self::PACKAGE_CHECKSUM_SEPARATOR .
			$sessionId .
			self::PACKAGE_CHECKSUM_SEPARATOR .
			$decodedContent[self::PACKAGE_CONTENT_EXTENSION]
		);

		// And return it
		return $hash;
	}

	///////////////////////////////////////////////////////////////////////////
	//                   Delivering packages / raw data
	///////////////////////////////////////////////////////////////////////////

	/**
	 * Declares the given raw package data by discovering recipients
	 *
	 * @param	$packageData	Raw package data in an array
	 * @return	void
	 */
	private function declareRawPackageData (array $packageData) {
		// Make sure the required field is there
		assert(isset($packageData[self::PACKAGE_DATA_RECIPIENT]));

		/*
		 * We need to disover every recipient, just in case we have a
		 * multi-recipient entry like 'upper' is. 'all' may be a not so good
		 * target because it causes an overload on the network and may be
		 * abused for attacking the network with large packages.
		 */
		$discoveryInstance = PackageDiscoveryFactory::createPackageDiscoveryInstance();

		// Discover all recipients, this may throw an exception
		$discoveryInstance->discoverRecipients($packageData);

		// Now get an iterator
		$iteratorInstance = $discoveryInstance->getIterator();

		// Make sure the iterator instance is valid
		assert($iteratorInstance instanceof Iterator);

		// Rewind back to the beginning
		$iteratorInstance->rewind();

		// ... and begin iteration
		while ($iteratorInstance->valid()) {
			// Get current entry
			$currentRecipient = $iteratorInstance->current();

			// Debug message
			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Setting recipient to ' . $currentRecipient . ',previous=' . $packageData[self::PACKAGE_DATA_RECIPIENT]);

			// Set the recipient
			$packageData[self::PACKAGE_DATA_RECIPIENT] = $currentRecipient;

			// Push the declared package to the next stack.
			$this->getStackInstance()->pushNamed(self::STACKER_NAME_DECLARED, $packageData);

			// Debug message
			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Package declared for recipient ' . $currentRecipient);

			// Skip to next entry
			$iteratorInstance->next();
		} // END - while

		/*
		 * The recipient list can be cleaned up here because the package which
		 * shall be delivered has already been added for all entries from the
		 * list.
		 */
		$discoveryInstance->clearRecipients();
	}

	/**
	 * Delivers raw package data. In short, this will discover the raw socket
	 * resource through a discovery class (which will analyse the receipient of
	 * the package), register the socket with the connection (handler/helper?)
	 * instance and finally push the raw data on our outgoing queue.
	 *
	 * @param	$packageData	Raw package data in an array
	 * @return	void
	 */
	private function deliverRawPackageData (array $packageData) {
		/*
		 * This package may become big, depending on the shared object size or
		 * delivered message size which shouldn't be so long (to save
		 * bandwidth). Because of the nature of the used protocol (TCP) we need
		 * to split it up into smaller pieces to fit it into a TCP frame.
		 *
		 * So first we need (again) a discovery class but now a protocol
		 * discovery to choose the right socket resource. The discovery class
		 * should take a look at the raw package data itself and then decide
		 * which (configurable!) protocol should be used for that type of
		 * package.
		 */
		$discoveryInstance = SocketDiscoveryFactory::createSocketDiscoveryInstance();

		// Now discover the right protocol
		$socketResource = $discoveryInstance->discoverSocket($packageData, BaseConnectionHelper::CONNECTION_TYPE_OUTGOING);

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Reached line ' . __LINE__ . ' after discoverSocket() has been called.');

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: stateInstance=' . $helperInstance->getStateInstance());
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Reached line ' . __LINE__ . ' before isSocketRegistered() has been called.');

		// The socket needs to be put in a special registry that can handle such data
		$registryInstance = SocketRegistryFactory::createSocketRegistryInstance();

		// Get the connection helper from registry
		$helperInstance = Registry::getRegistry()->getInstance('connection');

		// And make sure it is valid
		assert($helperInstance instanceof ConnectionHelper);

		// Get connection info class
		$infoInstance = ConnectionInfoFactory::createConnectionInfoInstance($helperInstance->getProtocolName(), 'helper');

		// Will the info instance with connection helper data
		$infoInstance->fillWithConnectionHelperInformation($helperInstance);

		// Is it not there?
		if ((is_resource($socketResource)) && (!$registryInstance->isSocketRegistered($infoInstance, $socketResource))) {
			// Debug message
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Registering socket ' . $socketResource . ' ...');

			// Then register it
			$registryInstance->registerSocket($infoInstance, $socketResource, $packageData);
		} elseif (!$helperInstance->getStateInstance()->isPeerStateConnected()) {
			// Is not connected, then we cannot send
			self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Unexpected peer state ' . $helperInstance->getStateInstance()->__toString() . ' detected.');

			// Shutdown the socket
			$this->shutdownSocket($socketResource);
		}

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Reached line ' . __LINE__ . ' after isSocketRegistered() has been called.');

		// Make sure the connection is up
		$helperInstance->getStateInstance()->validatePeerStateConnected();

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Reached line ' . __LINE__ . ' after validatePeerStateConnected() has been called.');

		// Enqueue it again on the out-going queue, the connection is up and working at this point
		$this->getStackInstance()->pushNamed(self::STACKER_NAME_OUTGOING, $packageData);

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Reached line ' . __LINE__ . ' after pushNamed() has been called.');
	}

	/**
	 * Sends waiting packages
	 *
	 * @param	$packageData	Raw package data
	 * @return	void
	 */
	private function sendOutgoingRawPackageData (array $packageData) {
		// Init sent bytes
		$sentBytes = 0;

		// Get the right connection instance
		$infoInstance = SocketRegistryFactory::createSocketRegistryInstance()->getInfoInstanceFromPackageData($packageData);

		// Test helper instance
		assert($infoInstance instanceof ShareableInfo);

		// Get helper instance
		$helperInstance = $infoInstance->getHelperInstance();

		// Some sanity-checks on the object
		//* DEBUG-DIE: */ die('[' . __METHOD__ . ':' . __LINE__ . ']: p1=' . $infoInstance->getProtocolName() . ',p2=' . $helperInstance->getProtocolName() . ',infoInstance=' . print_r($infoInstance, TRUE));
		assert($helperInstance instanceof ConnectionHelper);
		assert($infoInstance->getProtocolName() == $helperInstance->getProtocolName());

		// Is this connection still alive?
		if ($helperInstance->isShuttedDown()) {
			// This connection is shutting down
			// @TODO We may want to do somthing more here?
			return;
		} // END - if

		// Sent out package data
		$helperInstance->sendRawPackageData($packageData);
	}

	/**
	 * Generates a secure hash for given raw package content and sender id
	 *
	 * @param	$content	Raw package data
	 * @param	$senderId	Sender id to generate a hash for
	 * @return	$hash		Hash as hex-encoded string
	 */
	private function generatePackageHash ($content, $senderId) {
		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: content()=' . strlen($content) . ',senderId=' . $senderId . ' - CALLED!');

		// Is the feature enabled?
		if (!FrameworkFeature::isFeatureAvailable('hubcoin_reward')) {
			// Feature is not enabled
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Feature "hubcoin_reward" not available, not generating package hash. Returning NULL ...');
			return NULL;
		} // END - if

		// Fake array
		$data = array(
			self::PACKAGE_CONTENT_SENDER           => $senderId,
			self::PACKAGE_CONTENT_MESSAGE          => $content,
			self::PACKAGE_CONTENT_PRIVATE_KEY_HASH => ''
		);
	
		// Hash content and sender id together, use scrypt
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: senderId=' . $senderId . ',content()=' . strlen($content));
		$hash = FrameworkFeature::callFeature('hubcoin_reward', 'generateHash', array($senderId . ':' . $content . ':' . $this->determineSenderPrivateKeyHash($data)));

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: hash=' . $hash . ' - EXIT!');

		// Return it
		return $hash;
	}

	/**
	 * Checks whether the hash of given package data is 'valid', here that
	 * means it is the same or not.
	 *
	 * @param	$decodedArray		An array with 'decoded' (explode() was mostly called) data
	 * @return	$isHashValid	Whether the hash is valid
	 * @todo	Unfinished area, hashes are currently NOT fully supported
	 */
	private function isPackageHashValid (array $decodedArray) {
		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: decodedArray=' . print_r($decodedArray, TRUE) . ' - CALLED!');

		// Make sure the required array elements are there
		assert(isset($decodedArray[self::PACKAGE_CONTENT_SENDER]));
		assert(isset($decodedArray[self::PACKAGE_CONTENT_MESSAGE]));
		assert(isset($decodedArray[self::PACKAGE_CONTENT_HASH]));
		assert(isset($decodedArray[self::PACKAGE_CONTENT_PRIVATE_KEY_HASH]));

		// Is the feature enabled?
		if (!FrameworkFeature::isFeatureAvailable('hubcoin_reward')) {
			// Feature is not enabled, so hashes are always valid
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Feature "hubcoin_reward" not available, not checking hash. Returning TRUE ...');
			return TRUE;
		} // END - if

		// Check validity
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: senderId=' . $decodedArray[self::PACKAGE_CONTENT_SENDER] . ',message()=' . strlen($decodedArray[self::PACKAGE_CONTENT_MESSAGE]) . ',hash=' . $decodedArray[self::PACKAGE_CONTENT_HASH]);
		//* DEBUG-DIE: */ die(__METHOD__ . ': decodedArray=' . print_r($decodedArray, TRUE));
		$isHashValid = FrameworkFeature::callFeature('hubcoin_reward', 'checkHash', array($decodedArray[self::PACKAGE_CONTENT_SENDER] . ':' . $decodedArray[self::PACKAGE_CONTENT_MESSAGE] . ':' . $this->determineSenderPrivateKeyHash($decodedArray), $decodedArray[self::PACKAGE_CONTENT_HASH]));

		// Return it
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: isHashValid=' . intval($isHashValid) . ' - EXIT!');
		return $isHashValid;
	}

	/**
	 * "Enqueues" raw content into this delivery class by reading the raw content
	 * from given helper's template instance and pushing it on the 'undeclared'
	 * stack.
	 *
	 * @param	$helperInstance		An instance of a HubHelper class
	 * @return	void
	 */
	public function enqueueRawDataFromTemplate (HubHelper $helperInstance) {
		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': CALLED!');

		// Get the raw content ...
		$content = $helperInstance->getTemplateInstance()->getRawTemplateData();
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('content(' . strlen($content) . ')=' . $content);

		// ... and compress it
		$compressed = $this->getCompressorInstance()->compressStream($content);

		// Add magic in front of it and hash behind it, including BASE64 encoding
		$packageContent = sprintf(self::PACKAGE_MASK,
			// 1.) Compressor's extension
			$this->getCompressorInstance()->getCompressorExtension(),
			// - separator
			self::PACKAGE_MASK_SEPARATOR,
			// 2.) Compressed raw package content, encoded with BASE64
			base64_encode($compressed),
			// - separator
			self::PACKAGE_MASK_SEPARATOR,
			// 3.) Tags
			implode(self::PACKAGE_TAGS_SEPARATOR, $helperInstance->getPackageTags()),
			// - separator
			self::PACKAGE_MASK_SEPARATOR,
			// 4.) Checksum
			$this->getHashFromContent($compressed)
		);

		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': Enqueueing package for recipientType=' . $helperInstance->getRecipientType() . ' ...');

		// Now prepare the temporary array and push it on the 'undeclared' stack
		$this->getStackInstance()->pushNamed(self::STACKER_NAME_UNDECLARED, array(
			self::PACKAGE_DATA_SENDER           => $this->getSessionId(),
			self::PACKAGE_DATA_RECIPIENT        => $helperInstance->getRecipientType(),
			self::PACKAGE_DATA_CONTENT          => $packageContent,
			self::PACKAGE_DATA_STATUS           => self::PACKAGE_STATUS_NEW,
			self::PACKAGE_DATA_HASH             => $this->generatePackageHash($content, $this->getSessionId()),
			self::PACKAGE_DATA_PRIVATE_KEY_HASH => $this->getPrivateKeyHash(),
		));

		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': EXIT!');
	}

	/**
	 * Checks whether a package has been enqueued for delivery.
	 *
	 * @return	$isEnqueued		Whether a package is enqueued
	 */
	public function isPackageEnqueued () {
		// Check whether the stacker is not empty
		$isEnqueued = (($this->getStackInstance()->isStackInitialized(self::STACKER_NAME_UNDECLARED)) && (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_UNDECLARED)));

		// Return the result
		return $isEnqueued;
	}

	/**
	 * Checks whether a package has been declared
	 *
	 * @return	$isDeclared		Whether a package is declared
	 */
	public function isPackageDeclared () {
		// Check whether the stacker is not empty
		$isDeclared = (($this->getStackInstance()->isStackInitialized(self::STACKER_NAME_DECLARED)) && (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_DECLARED)));

		// Return the result
		return $isDeclared;
	}

	/**
	 * Checks whether a package should be sent out
	 *
	 * @return	$isWaitingDelivery	Whether a package is waiting for delivery
	 */
	public function isPackageWaitingForDelivery () {
		// Check whether the stacker is not empty
		$isWaitingDelivery = (($this->getStackInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING)) && (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING)));

		// Return the result
		return $isWaitingDelivery;
	}

	/**
	 * Checks whether encoded (raw) data is pending
	 *
	 * @return	$isPending		Whether encoded data is pending
	 */
	public function isEncodedDataPending () {
		// Check whether the stacker is not empty
		$isPending = (($this->getStackInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING_STREAM)) && (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING_STREAM)));

		// Return the result
		return $isPending;
	}

	/**
	 * Delivers an enqueued package to the stated destination. If a non-session
	 * id is provided, recipient resolver is being asked (and instanced once).
	 * This allows that a single package is being delivered to multiple targets
	 * without enqueueing it for every target. If no target is provided or it
	 * can't be determined a NoTargetException is being thrown.
	 *
	 * @return	void
	 * @throws	NoTargetException	If no target can't be determined
	 */
	public function declareEnqueuedPackage () {
		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': CALLED!');

		// Make sure this method isn't working if there is no package enqueued
		if (!$this->isPackageEnqueued()) {
			// This is not fatal but should be avoided
			self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: No raw package data waiting declaration, but ' . __METHOD__ . ' has been called!');
			return;
		} // END - if

		/*
		 * Now there are for sure packages to deliver, so start with the first
		 * one.
		 */
		$packageData = $this->getStackInstance()->popNamed(self::STACKER_NAME_UNDECLARED);

		// Declare the raw package data for delivery
		$this->declareRawPackageData($packageData);

		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': EXIT!');
	}

	/**
	 * Delivers the next declared package. Only one package per time will be sent
	 * because this may take time and slows down the whole delivery
	 * infrastructure.
	 *
	 * @return	void
	 */
	public function processDeclaredPackage () {
		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': CALLED!');

		// Sanity check if we have packages declared
		if (!$this->isPackageDeclared()) {
			// This is not fatal but should be avoided
			self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: No package has been declared, but ' . __METHOD__ . ' has been called!');
			return;
		} // END - if

		// Get the package
		$packageData = $this->getStackInstance()->getNamed(self::STACKER_NAME_DECLARED);

		// Assert on it
		assert(isset($packageData[self::PACKAGE_DATA_RECIPIENT]));

		// Try to deliver the package
		try {
			// And try to send it
			$this->deliverRawPackageData($packageData);

			// And remove it finally
			$this->getStackInstance()->popNamed(self::STACKER_NAME_DECLARED);
		} catch (UnexpectedStateException $e) {
			// The state is not excepected (shall be 'connected')
			self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Caught ' . $e->__toString() . ',message=' . $e->getMessage());

			// Mark the package with status failed
			$this->changePackageStatus($packageData, self::STACKER_NAME_DECLARED, self::PACKAGE_STATUS_FAILED);
		}

		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': EXIT!');
	}

	/**
	 * Sends waiting packages out for delivery
	 *
	 * @return	void
	 */
	public function sendWaitingPackage () {
		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': CALLED!');

		// Sanity check if we have packages waiting for delivery
		if (!$this->isPackageWaitingForDelivery()) {
			// This is not fatal but should be avoided
			self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: No package is waiting for delivery, but ' . __METHOD__ . ' was called.');
			return;
		} // END - if

		// Get the package
		$packageData = $this->getStackInstance()->getNamed(self::STACKER_NAME_OUTGOING);

		try {
			// Now try to send it
			$this->sendOutgoingRawPackageData($packageData);

			// And remove it finally
			$this->getStackInstance()->popNamed(self::STACKER_NAME_OUTGOING);
		} catch (InvalidSocketException $e) {
			// Output exception message
			self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Package was not delivered: ' . $e->getMessage());

			// Mark package as failed
			$this->changePackageStatus($packageData, self::STACKER_NAME_OUTGOING, self::PACKAGE_STATUS_FAILED);
		}

		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': EXIT!');
	}

	/**
	 * Sends out encoded data to a socket
	 *
	 * @return	void
	 */
	public function sendEncodedData () {
		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': CALLED!');

		// Make sure there is pending encoded data
		assert($this->isEncodedDataPending());

		// Pop current data from stack
		$encodedDataArray = $this->getStackInstance()->popNamed(self::STACKER_NAME_OUTGOING_STREAM);

		// Init in this round sent bytes
		$sentBytes = 0;

		// Assert on socket
		assert(is_resource($encodedDataArray[self::RAW_SOCKET_INDEX]));

		// And deliver it
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CONNECTION-HELPER[' . __METHOD__ . ':' . __LINE__ . ']: Sending out ' . strlen($encodedDataArray[self::RAW_ENCODED_DATA_INDEX]) . ' bytes,rawBufferSize=' . $encodedDataArray[self::RAW_BUFFER_SIZE_INDEX] . ',diff=' . $encodedDataArray[self::RAW_DIFF_INDEX]);
		if ($encodedDataArray[self::RAW_DIFF_INDEX] >= 0) {
			// Send all out (encodedData is smaller than or equal buffer size)
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CONNECTION-HELPER[' . __METHOD__ . ':' . __LINE__ . ']: MD5=' . md5(substr($encodedDataArray[self::RAW_ENCODED_DATA_INDEX], 0, ($encodedDataArray[self::RAW_BUFFER_SIZE_INDEX] - $encodedDataArray[self::RAW_DIFF_INDEX]))));
			$sentBytes = @socket_write($encodedDataArray[self::RAW_SOCKET_INDEX], $encodedDataArray[self::RAW_ENCODED_DATA_INDEX], ($encodedDataArray[self::RAW_BUFFER_SIZE_INDEX] - $encodedDataArray[self::RAW_DIFF_INDEX]));
		} else {
			// Send buffer size out
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CONNECTION-HELPER[' . __METHOD__ . ':' . __LINE__ . ']: MD5=' . md5(substr($encodedDataArray[self::RAW_ENCODED_DATA_INDEX], 0, $encodedDataArray[self::RAW_BUFFER_SIZE_INDEX])));
			$sentBytes = @socket_write($encodedDataArray[self::RAW_SOCKET_INDEX], $encodedDataArray[self::RAW_ENCODED_DATA_INDEX], $encodedDataArray[self::RAW_BUFFER_SIZE_INDEX]);
		}

		// If there was an error, we don't continue here
		if ($sentBytes === FALSE) {
			// Handle the error with a faked recipientData array
			$this->handleSocketError(__METHOD__, __LINE__, $encodedDataArray[self::RAW_SOCKET_INDEX], array('0.0.0.0', '0'));

			// And throw it
			throw new InvalidSocketException(array($this, $encodedDataArray[self::RAW_SOCKET_INDEX], $socketError, $errorMessage), BaseListener::EXCEPTION_INVALID_SOCKET);
		} elseif (($sentBytes === 0) && (strlen($encodedDataArray[self::RAW_ENCODED_DATA_INDEX]) > 0)) {
			// Nothing sent means we are done
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CONNECTION-HELPER[' . __METHOD__ . ':' . __LINE__ . ']: All sent! (LINE=' . __LINE__ . ')');
			return;
		} else {
			// The difference between sent bytes and length of raw data should not go below zero
			assert((strlen($encodedDataArray[self::RAW_ENCODED_DATA_INDEX]) - $sentBytes) >= 0);

			// Add total sent bytes
			$encodedDataArray[self::RAW_SENT_BYTES_INDEX] += $sentBytes;

			// Cut out the last unsent bytes
			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CONNECTION-HELPER[' . __METHOD__ . ':' . __LINE__ . ']: Sent out ' . $sentBytes . ' of ' . strlen($encodedDataArray[self::RAW_ENCODED_DATA_INDEX]) . ' bytes ...');
			$encodedDataArray[self::RAW_ENCODED_DATA_INDEX] = substr($encodedDataArray[self::RAW_ENCODED_DATA_INDEX], $sentBytes);

			// Calculate difference again
			$encodedDataArray[self::RAW_DIFF_INDEX] = $encodedDataArray[self::RAW_BUFFER_SIZE_INDEX] - strlen($encodedDataArray[self::RAW_ENCODED_DATA_INDEX]);

			// Can we abort?
			if (strlen($encodedDataArray[self::RAW_ENCODED_DATA_INDEX]) <= 0) {
				// Abort here, all sent!
				//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('CONNECTION-HELPER[' . __METHOD__ . ':' . __LINE__ . ']: All sent! (LINE=' . __LINE__ . ')');
				return;
			} // END - if
		}

		// Push array back in stack
		$this->getStackInstance()->pushNamed(self::STACKER_NAME_OUTGOING_STREAM, $encodedDataArray);

		// Debug message
		//* DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . ': EXIT!');
	}

	///////////////////////////////////////////////////////////////////////////
	//                   Receiving packages / raw data
	///////////////////////////////////////////////////////////////////////////

	/**
	 * Checks whether decoded raw data is pending
	 *
	 * @return	$isPending	Whether decoded raw data is pending
	 */
	private function isRawDataPending () {
		// Just return whether the stack is not empty
		$isPending = (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_DECODED_INCOMING));

		// Return the status
		return $isPending;
	}

	/**
	 * Checks whether new raw package data has arrived at a socket
	 *
	 * @return	$hasArrived		Whether new raw package data has arrived for processing
	 */
	public function isNewRawDataPending () {
		// Visit the pool. This monitors the pool for incoming raw data.
		$this->getListenerPoolInstance()->accept($this->getVisitorInstance());

		// Check for new data arrival
		$hasArrived = $this->isRawDataPending();

		// Return the status
		return $hasArrived;
	}

	/**
	 * Handles the incoming decoded raw data. This method does not "convert" the
	 * decoded data back into a package array, it just "handles" it and pushs it
	 * on the next stack.
	 *
	 * @return	void
	 */
	public function handleIncomingDecodedData () {
		/*
		 * This method should only be called if decoded raw data is pending,
		 * so check it again.
		 */
		if (!$this->isRawDataPending()) {
			// This is not fatal but should be avoided
			self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: No raw (decoded?) data is pending, but ' . __METHOD__ . ' has been called!');
			return;
		} // END - if

		// Very noisy debug message:
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Stacker size is ' . $this->getStackInstance()->getStackCount(self::STACKER_NAME_DECODED_INCOMING) . ' entries.');

		// "Pop" the next entry (the same array again) from the stack
		$decodedData = $this->getStackInstance()->popNamed(self::STACKER_NAME_DECODED_INCOMING);

		// Make sure both array elements are there
		assert(
			(is_array($decodedData)) &&
			(isset($decodedData[BaseRawDataHandler::PACKAGE_RAW_DATA])) &&
			(isset($decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE]))
		);

		/*
		 * Also make sure the error code is SOCKET_ERROR_UNHANDLED because we
		 * only want to handle unhandled packages here.
		 */
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: errorCode=' . $decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE] . '(' . BaseRawDataHandler::SOCKET_ERROR_UNHANDLED . ')');
		assert($decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE] == BaseRawDataHandler::SOCKET_ERROR_UNHANDLED);

		// Remove the last chunk SEPARATOR (because there is no need for it)
		if (substr($decodedData[BaseRawDataHandler::PACKAGE_RAW_DATA], -1, 1) == PackageFragmenter::CHUNK_SEPARATOR) {
			// It is there and should be removed
			$decodedData[BaseRawDataHandler::PACKAGE_RAW_DATA] = substr($decodedData[BaseRawDataHandler::PACKAGE_RAW_DATA], 0, -1);
		} // END - if

		// This package is "handled" and can be pushed on the next stack
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Pushing ' . strlen($decodedData[BaseRawDataHandler::PACKAGE_RAW_DATA]) . ' bytes to stack ' . self::STACKER_NAME_DECODED_HANDLED . ' ...');
		$this->getStackInstance()->pushNamed(self::STACKER_NAME_DECODED_HANDLED, $decodedData);
	}

	/**
	 * Adds raw decoded data from the given handler instance to this receiver
	 *
	 * @param	$handlerInstance	An instance of a Networkable class
	 * @return	void
	 */
	public function addRawDataToIncomingStack (Networkable $handlerInstance) {
		/*
		 * Get the decoded data from the handler, this is an array with
		 * 'raw_data' and 'error_code' as elements.
		 */
		$decodedData = $handlerInstance->getNextRawData();

		// Very noisy debug message:
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: decodedData[' . gettype($decodedData) . ']=' . print_r($decodedData, TRUE));

		// And push it on our stack
		$this->getStackInstance()->pushNamed(self::STACKER_NAME_DECODED_INCOMING, $decodedData);
	}

	/**
	 * Checks whether incoming decoded data is handled.
	 *
	 * @return	$isHandled	Whether incoming decoded data is handled
	 */
	public function isIncomingRawDataHandled () {
		// Determine if the stack is not empty
		$isHandled = (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_DECODED_HANDLED));

		// Return it
		return $isHandled;
	}

	/**
	 * Checks whether the assembler has pending data left
	 *
	 * @return	$isHandled	Whether the assembler has pending data left
	 */
	public function ifAssemblerHasPendingDataLeft () {
		// Determine if the stack is not empty
		$isHandled = (!$this->getAssemblerInstance()->isPendingDataEmpty());

		// Return it
		return $isHandled;
	}

	/**
	 * Checks whether the assembler has multiple packages pending
	 *
	 * @return	$isPending	Whether the assembler has multiple packages pending
	 */
	public function ifMultipleMessagesPending () {
		// Determine if the stack is not empty
		$isPending = ($this->getAssemblerInstance()->ifMultipleMessagesPending());

		// Return it
		return $isPending;
	}

	/**
	 * Handles the attached assemler's pending data queue to be finally
	 * assembled to the raw package data back.
	 *
	 * @return	void
	 */
	public function handleAssemblerPendingData () {
		// Handle it
		$this->getAssemblerInstance()->handlePendingData();
	}

	/**
	 * Handles multiple messages.
	 *
	 * @return	void
	 */
	public function handleMultipleMessages () {
		// Handle it
		$this->getAssemblerInstance()->handleMultipleMessages();
	}

	/**
	 * Assembles incoming decoded data so it will become an abstract network
	 * package again. The assembler does later do it's job by an other task,
	 * not this one to keep best speed possible.
	 *
	 * @return	void
	 */
	public function assembleDecodedDataToPackage () {
		// Make sure the raw decoded package data is handled
		assert($this->isIncomingRawDataHandled());

		// Get current package content (an array with two elements; see handleIncomingDecodedData() for details)
		$packageContent = $this->getStackInstance()->getNamed(self::STACKER_NAME_DECODED_HANDLED);

		// Assert on some elements
		assert(
			(is_array($packageContent)) &&
			(isset($packageContent[BaseRawDataHandler::PACKAGE_RAW_DATA])) &&
			(isset($packageContent[BaseRawDataHandler::PACKAGE_ERROR_CODE]))
		);

		// Start assembling the raw package data array by chunking it
		$this->getAssemblerInstance()->chunkPackageContent($packageContent);

		// Remove the package from 'handled_decoded' stack ...
		$this->getStackInstance()->popNamed(self::STACKER_NAME_DECODED_HANDLED);

		// ... and push it on the 'chunked' stacker
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: Pushing ' . strlen($packageContent[BaseRawDataHandler::PACKAGE_RAW_DATA]) . ' bytes on stack ' . self::STACKER_NAME_DECODED_CHUNKED . ',packageContent=' . print_r($packageContent, TRUE));
		$this->getStackInstance()->pushNamed(self::STACKER_NAME_DECODED_CHUNKED, $packageContent);
	}

	/**
	 * Accepts the visitor to process the visit "request"
	 *
	 * @param	$visitorInstance	An instance of a Visitor class
	 * @return	void
	 */
	public function accept (Visitor $visitorInstance) {
		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: ' . $visitorInstance->__toString() . ' has visited - CALLED!');

		// Visit the package
		$visitorInstance->visitNetworkPackage($this);

		// Then visit the assembler to handle multiple packages
		$this->getAssemblerInstance()->accept($visitorInstance);

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: ' . $visitorInstance->__toString() . ' has visited - EXIT!');
	}

	/**
	 * Clears all stacks
	 *
	 * @return	void
	 */
	public function clearAllStacks () {
		// Call the init method to force re-initialization
		$this->initStacks(TRUE);

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: All stacker have been re-initialized.');
	}

	/**
	 * Removes the first failed outoging package from the stack to continue
	 * with next one (it will never work until the issue is fixed by you).
	 *
	 * @return	void
	 * @throws	UnexpectedPackageStatusException	If the package status is not 'failed'
	 * @todo	This may be enchanced for outgoing packages?
	 */
	public function removeFirstFailedPackage () {
		// Get the package again
		$packageData = $this->getStackInstance()->getNamed(self::STACKER_NAME_DECLARED);

		// Is the package status 'failed'?
		if ($packageData[self::PACKAGE_DATA_STATUS] != self::PACKAGE_STATUS_FAILED) {
			// Not failed!
			throw new UnexpectedPackageStatusException(array($this, $packageData, self::PACKAGE_STATUS_FAILED), BaseListener::EXCEPTION_UNEXPECTED_PACKAGE_STATUS);
		} // END - if

		// Remove this entry
		$this->getStackInstance()->popNamed(self::STACKER_NAME_DECLARED);
	}

	/**
	 * "Decode" the package content into the same array when it was sent.
	 *
	 * @param	$rawPackageContent	The raw package content to be "decoded"
	 * @return	$decodedData		An array with 'sender', 'recipient', 'content' and 'status' elements
	 */
	public function decodeRawContent ($rawPackageContent) {
		// Use the separator '#' to "decode" it
		$decodedArray = explode(self::PACKAGE_DATA_SEPARATOR, $rawPackageContent);

		// Assert on count (should be always 3)
		assert(count($decodedArray) == self::DECODED_DATA_ARRAY_SIZE);

		/*
		 * Create 'decodedData' array with all assoziative array elements.
		 */
		$decodedData = array(
			self::PACKAGE_DATA_SENDER           => $decodedArray[self::INDEX_PACKAGE_SENDER],
			self::PACKAGE_DATA_RECIPIENT        => $decodedArray[self::INDEX_PACKAGE_RECIPIENT],
			self::PACKAGE_DATA_CONTENT          => $decodedArray[self::INDEX_PACKAGE_CONTENT],
			self::PACKAGE_DATA_STATUS           => self::PACKAGE_STATUS_DECODED,
			self::PACKAGE_DATA_HASH             => $decodedArray[self::INDEX_PACKAGE_HASH],
			self::PACKAGE_DATA_PRIVATE_KEY_HASH => $decodedArray[self::INDEX_PACKAGE_PRIVATE_KEY_HASH]
		);

		// And return it
		return $decodedData;
	}

	/**
	 * Handles decoded data for this node by "decoding" the 'content' part of
	 * it. Again this method uses explode() for the "decoding" process.
	 *
	 * @param	$decodedData	An array with decoded raw package data
	 * @return	void
	 * @throws	InvalidDataChecksumException	If the checksum doesn't match
	 */
	public function handleRawData (array $decodedData) {
		/*
		 * "Decode" the package's content by a simple explode() call, for
		 * details of the array elements, see comments for constant
		 * PACKAGE_MASK.
		 */
		$decodedContent = explode(self::PACKAGE_MASK_SEPARATOR, $decodedData[self::PACKAGE_DATA_CONTENT]);

		// Assert on array count for a very basic validation
		assert(count($decodedContent) == self::PACKAGE_CONTENT_ARRAY_SIZE);

		/*
		 * Convert the indexed array into an associative array. This is much
		 * better to remember than plain numbers, isn't it?
		 */
		$decodedContent = array(
			// Compressor's extension used to compress the data
			self::PACKAGE_CONTENT_EXTENSION        => $decodedContent[self::INDEX_COMPRESSOR_EXTENSION],
			// Package data (aka "message") in BASE64-decoded form but still compressed
			self::PACKAGE_CONTENT_MESSAGE          => base64_decode($decodedContent[self::INDEX_PACKAGE_DATA]),
			// Tags as an indexed array for "tagging" the message
			self::PACKAGE_CONTENT_TAGS             => explode(self::PACKAGE_TAGS_SEPARATOR, $decodedContent[self::INDEX_TAGS]),
			// Checksum of the _decoded_ data
			self::PACKAGE_CONTENT_CHECKSUM         => $decodedContent[self::INDEX_CHECKSUM],
			// Sender's id
			self::PACKAGE_CONTENT_SENDER           => $decodedData[self::PACKAGE_DATA_SENDER],
			// Hash from decoded raw data
			self::PACKAGE_CONTENT_HASH             => $decodedData[self::PACKAGE_DATA_HASH],
			// Hash of private key
			self::PACKAGE_CONTENT_PRIVATE_KEY_HASH => $decodedData[self::PACKAGE_DATA_PRIVATE_KEY_HASH]
		);

		// Is the checksum valid?
		if (!$this->isChecksumValid($decodedContent, $decodedData)) {
			// Is not the same, so throw an exception here
			throw new InvalidDataChecksumException(array($this, $decodedContent, $decodedData), BaseListener::EXCEPTION_INVALID_DATA_CHECKSUM);
		} // END - if

		/*
		 * The checksum is the same, then it can be decompressed safely. The
		 * original message is at this point fully decoded.
		 */
		$decodedContent[self::PACKAGE_CONTENT_MESSAGE] = $this->getCompressorInstance()->decompressStream($decodedContent[self::PACKAGE_CONTENT_MESSAGE]);

		// And push it on the next stack
		$this->getStackInstance()->pushNamed(self::STACKER_NAME_NEW_MESSAGE, $decodedContent);
	}

	/**
	 * Checks whether a new message has arrived
	 *
	 * @return	$hasArrived		Whether a new message has arrived for processing
	 */
	public function isNewMessageArrived () {
		// Determine if the stack is not empty
		$hasArrived = (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_NEW_MESSAGE));

		// Return it
		return $hasArrived;
	}

	/**
	 * Handles newly arrived messages
	 *
	 * @return	void
	 * @todo	Implement verification of all sent tags here?
	 */
	public function handleNewlyArrivedMessage () {
		// Make sure there is at least one message
		assert($this->isNewMessageArrived());

		// Get it from the stacker, it is the full array with the decoded message
		$decodedContent = $this->getStackInstance()->popNamed(self::STACKER_NAME_NEW_MESSAGE);

		// Generate the hash of comparing it
		if (!$this->isPackageHashValid($decodedContent)) {
			// Is not valid, so throw an exception here
			exit(__METHOD__ . ':INVALID HASH! UNDER CONSTRUCTION!' . chr(10));
		} // END - if

		// Now get a filter chain back from factory with given tags array
		$chainInstance = PackageFilterChainFactory::createChainByTagsArray($decodedContent[self::PACKAGE_CONTENT_TAGS]);

		/*
		 * Process the message through all filters, note that all other
		 * elements from $decodedContent are no longer needed.
		 */
		$chainInstance->processMessage($decodedContent, $this);

		/*
		 * Post-processing of message data (this won't remove the message from
		 * the stack).
		 */
		$chainInstance->postProcessMessage($this);
	}

	/**
	 * Checks whether a processed message is pending for "interpretation"
	 *
	 * @return	$isPending	Whether a processed message is pending
	 */
	public function isProcessedMessagePending () {
		// Check it
		$isPending = (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_PROCESSED_MESSAGE));

		// Return it
		return $isPending;
	}

	/**
	 * Handle processed messages by "interpreting" the 'message_type' element
	 *
	 * @return	void
	 */
	public function handleProcessedMessage () {
		// Get it from the stacker, it is the full array with the processed message
		$messageArray = $this->getStackInstance()->popNamed(self::STACKER_NAME_PROCESSED_MESSAGE);

		// Add type for later easier handling
		$messageArray[self::MESSAGE_ARRAY_DATA][self::MESSAGE_ARRAY_TYPE] = $messageArray[self::MESSAGE_ARRAY_TYPE];

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: messageArray=' . print_r($messageArray, TRUE));

		// Create a handler instance from given message type
		$handlerInstance = MessageTypeHandlerFactory::createMessageTypeHandlerInstance($messageArray[self::MESSAGE_ARRAY_TYPE]);

		// Handle message data
		$handlerInstance->handleMessageData($messageArray[self::MESSAGE_ARRAY_DATA], $this);

		// Post-handling of message data
		$handlerInstance->postHandleMessageData($messageArray, $this);
	}

	/**
	 * Feeds the hash and sender (as recipient for the 'sender' reward) to the
	 * miner's queue, unless the message is not a "reward claim" message as this
	 * leads to an endless loop. You may wish to run the miner to get some
	 * reward ("Hubcoins") for "mining" this hash.
	 *
	 * @param	$messageData	Array with message data
	 * @return	void
	 * @todo	~10% done?
	 */
	public function feedHashToMiner (array $messageData) {
		// Is the feature enabled?
		if (!FrameworkFeature::isFeatureAvailable('hubcoin_reward')) {
			/*
			 * Feature is not enabled, don't feed the hash to the miner as it
			 *may be invalid.
			 */
			return;
		} // END - if

		// Make sure the required elements are there
		assert(isset($messageData[self::MESSAGE_ARRAY_SENDER]));
		assert(isset($messageData[self::MESSAGE_ARRAY_HASH]));
		assert(isset($messageData[self::MESSAGE_ARRAY_TAGS]));

		// Debug message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('NETWORK-PACKAGE[' . __METHOD__ . ':' . __LINE__ . ']: messageData=' . print_r($messageData, TRUE));

		// Resolve session id ('sender' is a session id) into node id
		$nodeId = HubTools::resolveNodeIdBySessionId($messageData[self::MESSAGE_ARRAY_SENDER]);

		// Is 'claim_reward' the message type?
		if (in_array('claim_reward', $messageData[self::MESSAGE_ARRAY_TAGS])) {
			/*
			 * Then don't feed this message to the miner as this causes an
			 * endless loop of mining.
			 */
			return;
		} // END - if

		$this->partialStub('@TODO nodeId=' . $nodeId . ',messageData=' . print_r($messageData, TRUE));
	}
}

// [EOF]
?>