<?php
/**
 * A class for handling commands to and from hubs including the master hub
 *
 * @author		Roland Haeder <webmaster@ship-simu.org>
 * @version		0.0
 * @copyright	Copyright(c) 2007, 2008 Roland Haeder, this is free software
 * @license		GNU GPL 3.0 or any newer version
 *
 * 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 HubCommandProcessor extends BaseFrameworkSystem {
	/**
	 * An instance of a HubPeer class
	 */
	private $peerInstance = null;

	/**
	 * A list of sent commands but not replied (yet)
	 */
	private $sentCommandsAwaitingAnswer = array();

	/**
	 * Queued commands from the master hub
	 */
	private $masterCommands = array();

	// Exceptions
	const EXCEPTION_COMMAND_AWAIT_INVALID	= 0xc00;

	/**
	 * The private constructor
	 *
	 * @return	void
	 */
	private function __construct () {
		// Call parent constructor
		parent::constructor(__CLASS__);

		// Set description
		$this->setObjectDescription("Hub-Command-Processor");

		// Set unique ID
		$this->createUniqueID();

		// Tidy up a little
		$this->removeSystemArray();
		$this->removeNumberFormaters();
	}

	/**
	 * Creates an instance of a HubCommandProcessor class by a HubPeer class
	 *
	 * @param		$peerInstance		An instance of a HubPeer class
	 * @return	$command			An instance of this class
	 */
	public final static function createHubCommandProcessor (HubPeer $peerInstance) {
		// Get a new instance of this class
		$command = new HubCommandProcessor();

		// Set the hub instance
		$command->setPeerInstance($peerInstance);

		// Return the instance
		return $command;
	}

	/**
	 * Setter for HubPeer instances
	 *
	 * @param		$peerInstance		An instance of a HubPeer class
	 * @return	void
	 */
	public final function setPeerInstance(HubPeer $peerInstance) {
		$this->peerInstance = $peerInstance;
	}

	/**
	 * Getter for HubPeer instances
	 *
	 * @return	$peerInstance		An instance of a HubPeer class
	 */
	public final function getPeerInstance() {
		return $this->peerInstance;
	}

	/**
	 * Handles simple commands which require an answer command from the peer without any parameters
	 *
	 * @param		$sendCommand		The command we shall send to the peer
	 * @param		$expectCommand		The command we except from the peer
	 * @return	void
	 */
	public function simpleExecute ($sendCommand, $expectCommand) {
		// Remember the command
		$this->sentCommandsAwaitingAnswer[$expectCommand] = $sendCommand;

		// Debug message
		$this->getPeerInstance()->getHubInstance()->getOutputInstance()->output(sprintf("[%s] Sending command %s to peer %s",
			$this->__toString(),
			$sendCommand,
			$this->getPeerInstance()->getValidatedIP()
		));

		// Execute the command
		$this->getPeerInstance()->sendMessage($sendCommand);
	}

	/**
	 * Awaits a specified command from the peer and returns TRUE if received or FALSE if not.
	 *
	 * @param		$exceptCommand					The command we are expecting from the peer
	 * @return	$await						Wether the awaited command has been received
	 * @throws	UnexpectedAwaitCommandException	If the awaited command is not being awaited...
	 */
	public function ifAwaitsCommand ($expectCommand) {
		$await = false;

		// Do we wait for this command?
		if (!isset($this->sentCommandsAwaitingAnswer[$expectCommand])) {
			// We are not waiting for this command
			throw new UnexpectedAwaitCommandException (
				array(
					'this'	=> $this,
					'await'	=> $expectCommand
				), self::EXCEPTION_COMMAND_AWAIT_INVALID
			);
		} // END - if

		// Then process it... :-)
		$readCommand = $this->getPeerInstance()->readFromSocket();

		// Is the command not empty?
		if (!empty($readCommand)) {
			// Debug message
			$this->getPeerInstance()->getHubInstance()->getOutputInstance()->output(sprintf("[%s] Raw command %s received from peer %s",
				$this->__toString(),
				$readCommand,
				$this->getPeerInstance()->getValidatedIP()
			));
		} // END - if

		if ($readCommand == $expectCommand) {
			// Debug message
			$this->getPeerInstance()->getHubInstance()->getOutputInstance()->output(sprintf("[%s] Awaited command %s received from peer %s",
				$this->__toString(),
				$expectCommand,
				$this->getPeerInstance()->getValidatedIP()
			));

			// Expected command has been received!
			unset($this->sentCommandsAwaitingAnswer[$expectCommand]);
			$await = true;

		} // END - if

		// Return the result
		return $await;
	}

	/**
	 * Awaits any command from the peer
	 *
	 * @return	$command		The sent command from the peer
	 */
	public function awaitAnyCommand () {
		$command = false;
		$readCommand = $this->getPeerInstance()->readFromSocket();
		if (!empty($readCommand)) {
			// Remember this command
			// TODO Add some validation here!
			$this->masterCommands[] = $readCommand;

			// A command is in the queue
			$command = true;
		} // END - if

		// Return status
		return $command;
	}

} // END - class

// [EOF]
?>