<?php
/**
 * A general ConnectionHelper class
 *
 * @author		Roland Haeder <webmaster@ship-simu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2011 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 BaseConnectionHelper extends BaseHubHelper implements Registerable, ProtocolHandler {
	/**
	 * Protocol used
	 */
	private $protocol = 'invalid';

	/**
	 * Port number used
	 */
	private $port = 0;

	/**
	 * (IP) Adress used
	 */
	private $address = 0;

	/**
	 * Sent data in bytes
	 */
	private $sentData = 0;

	/**
	 * Difference
	 */
	private $diff = 0;

	/**
	 * Connect retries for this connection
	 */
	private $retryCount = 0;

	/**
	 * Wether this connection is shutted down
	 */
	private $shuttedDown = false;

	/**
	 * Currently queued chunks
	 */
	private $queuedChunks = array();

	/**
	 * Current final hash
	 */
	private $currentFinalHash = '';

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

		// Register this connection helper
		Registry::getRegistry()->addInstance('connection', $this);

		// Initialize output stream
		$streamInstance = ObjectFactory::createObjectByConfiguredName('node_raw_data_output_stream_class');

		// And add it to this connection helper
		$this->setOutputStreamInstance($streamInstance);
	}

	/**
	 * Getter for port number to satify ProtocolHandler
	 *
	 * @return	$port	The port number
	 */
	public final function getPort () {
		return $this->port;
	}

	/**
	 * Setter for port number to satify ProtocolHandler
	 *
	 * @param	$port	The port number
	 * @return	void
	 */
	protected final function setPort ($port) {
		$this->port = $port;
	}

	/**
	 * Getter for protocol
	 *
	 * @return	$protocol	Used protocol
	 */
	public final function getProtocol () {
		return $this->protocol;
	}

	/**
	 * Setter for protocol
	 *
	 * @param	$protocol	Used protocol
	 * @return	void
	 */
	protected final function setProtocol ($protocol) {
		$this->protocol = $protocol;
	}

	/**
	 * Getter for IP address
	 *
	 * @return	$address	The IP address
	 */
	public final function getAddress () {
		return $this->address;
	}

	/**
	 * Setter for IP address
	 *
	 * @param	$address	The IP address
	 * @return	void
	 */
	protected final function setAddress ($address) {
		$this->address = $address;
	}

	/**
	 * "Getter" for raw data from a package array. A fragmenter is used which
	 * will returns us only so many raw data which fits into the back buffer.
	 * The rest is being held in a back-buffer and waits there for the next
	 * cycle and while be then sent.
	 *
	 * This method does 4 simple steps:
	 * 1) Aquire fragmenter object instance from the factory
	 * 2) Handle over the package data array to the fragmenter
	 * 3) Request a chunk
	 * 4) Finally return the chunk (array) to the caller
	 *
	 * @param	$packageData	Raw package data array
	 * @return	$chunkData		Raw data chunk
	 */
	private function getRawDataFromPackageArray (array $packageData) {
		// Get the fragmenter instance
		$fragmenterInstance = FragmenterFactory::createFragmenterInstance('package');

		// Implode the package data array and fragement the resulting string, returns the final hash
		$finalHash = $fragmenterInstance->fragmentPackageArray($packageData, $this);
		if ($finalHash !== true) {
			$this->currentFinalHash = $finalHash;
		} // END - if

		// Debug message
		//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: currentFinalHash=' . $this->currentFinalHash);

		// Get the next raw data chunk from the fragmenter
		$rawDataChunk = $fragmenterInstance->getNextRawDataChunk($this->currentFinalHash);

		// Get chunk hashes and chunk data
		$chunkHashes = array_keys($rawDataChunk);
		$chunkData   = array_values($rawDataChunk);

		// Is the required data there?
		//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: chunkHashes[]=' . count($chunkHashes) . ',chunkData[]=' . count($chunkData));
		if ((isset($chunkHashes[0])) && (isset($chunkData[0]))) {
			// Remember this chunk as queued
			$this->queuedChunks[$chunkHashes[0]] = $chunkData[0];

			// Return the raw data
			return $chunkData[0];
		} else {
			// Return zero string
			return '';
		}
	}

	/**
	 * "Accept" a visitor by simply calling it back
	 *
	 * @param	$visitorInstance	A Visitor instance
	 * @return	void
	 */
	protected final function accept (Visitor $visitorInstance) {
		// Just call the visitor
		$visitorInstance->visitConnectionHelper($this);
	}

	/**
	 * Sends raw package data to the recipient
	 *
	 * @param	$packageData		Raw package data
	 * @return	$totalSentBytes		Total sent bytes to the peer
	 * @throws	InvalidSocketException	If we got a problem with this socket
	 */
	public function sendRawPackageData (array $packageData) {
		// Cache buffer length
		$bufferSize = $this->getConfigInstance()->getConfigEntry($this->getProtocol() . '_buffer_length');

		// Init variables
		$rawData        = '';
		$dataStream     = ' ';
		$totalSentBytes = 0;

		// Fill sending buffer with data
		while ((strlen($rawData) < $bufferSize) && (strlen($dataStream) > 0)) {
			// Convert the package data array to a raw data stream
			$dataStream = $this->getRawDataFromPackageArray($packageData);
			//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: Adding ' . strlen($dataStream) . ' bytes to the sending buffer ...');
			$rawData .= $dataStream;
		} // END - while

		// Nothing to sent is bad news!
		assert(strlen($rawData) > 0);

		// Encode the raw data with our output-stream
		$encodedData = $this->getOutputStreamInstance()->streamData($rawData);

		// Calculate difference
		$this->diff = $bufferSize - strlen($encodedData);

		// Get socket resource
		$socketResource = $this->getSocketResource();

		// Init sent bytes
		$sentBytes = 0;

		// Deliver all data
		while ($sentBytes !== false) {
			// And deliver it
			//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: Sending out ' . strlen($encodedData) . ' bytes,bufferSize=' . $bufferSize . ',diff=' . $this->diff);
			$sentBytes = @socket_write($socketResource, $encodedData, ($bufferSize - $this->diff));

			// If there was an error, we don't continue here
			if ($sentBytes === false) {
				// Get socket error code for verification
				$socketError = socket_last_error($socketResource);

				// Get error message
				$errorMessage = socket_strerror($socketError);

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

				// And throw it
				throw new InvalidSocketException(array($this, gettype($socketResource), $socketError, $errorMessage), BaseListener::EXCEPTION_INVALID_SOCKET);
			} elseif (($sentBytes == 0) && (strlen($encodedData) > 0)) {
				// Nothing sent means we are done
				//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: All sent! (' . __LINE__ . ')');
				break;
			}

			// The difference between sent bytes and length of raw data should not be below zero
			assert((strlen($encodedData) - $sentBytes) >= 0);

			// Add total sent bytes
			$totalSentBytes += $sentBytes;

			// Cut out the last unsent bytes
			//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: Sent out ' . $sentBytes . ' of ' . strlen($encodedData) . ' bytes ...');
			$encodedData = substr($encodedData, $sentBytes);

			// Calculate difference again
			$this->diff = $bufferSize - strlen($encodedData);

			// Can we abort?
			if (strlen($encodedData) <= 0) {
				// Abort here, all sent!
				//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: All sent! (' . __LINE__ . ')');
				break;
			} // END - if
		} // END - while

		// Return sent bytes
		//* NOISY-DEBUG: */ $this->debugOutput('CONNECTION: totalSentBytes=' . $totalSentBytes);
		return $totalSentBytes;
	}

	/**
	 * Getter for real class name
	 *
	 * @return	$class	Name of this class
	 */
	public function __toString () {
		// Class name representation
		$class = $this->getAddress() . ':' . $this->getPort() . ':' . parent::__toString();

		// Return it
		return $class;
	}

	/**
	 * Checks wether the connect retry is exhausted
	 *
	 * @return	$isExhaused		Wether connect retry is exchausted
	 */
	public final function isConnectRetryExhausted () {
		// Construct config entry
		$configEntry = $this->getProtocol() . '_connect_retry_max';

		// Check it out
		$isExhausted = ($this->retryCount >=  $this->getConfigInstance()->getConfigEntry($configEntry));

		// Return it
		return $isExhausted;
	}

	/**
	 * Increases the connect retry count
	 *
	 * @return	void
	 */
	public final function increaseConnectRetry () {
		$this->retryCount++;
	}

	/**
	 * Marks this connection as shutted down
	 *
	 * @return	void
	 */
	protected final function markConnectionShutdown () {
		$this->shuttedDown = true;
	}

	/**
	 * Getter for shuttedDown
	 *
	 * @return	$shuttedDown	Wether this connection is shutted down
	 */
	public final function isShuttedDown () {
		return $this->shuttedDown;
	}
}

// [EOF]
?>