application/hub/classes/decoder/package/class_PackageDecoder.php

   1 <?php
   2 /**
   3  * A Package decoder class
   4  *
   5  * @author              Roland Haeder <webmaster@shipsimu.org>
   6  * @version             0.0.0
   7  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 Hub Developer Team
   8  * @license             GNU GPL 3.0 or any newer version
   9  * @link                http://www.shipsimu.org
  10  *
  11  * This program is free software: you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation, either version 3 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  */
  24 class PackageDecoder extends BaseDecoder implements Decodeable, Registerable {
  25         /**
  26          * Name for stacker for received packages
  27          */
  28         const STACKER_NAME_DECODED_PACKAGE = 'decoded_package';
  29
  30         /**
  31          * Protected constructor
  32          *
  33          * @return      void
  34          */
  35         protected function __construct () {
  36                 // Call parent constructor
  37                 parent::__construct(__CLASS__);
  38         }
  39
  40         /**
  41          * Creates an instance of this class
  42          *
  43          * @param       $handlerInstance        An instance of a HandleableChunks class
  44          * @return      $decoderInstance        An instance of a Decodeable class
  45          */
  46         public final static function createPackageDecoder (HandleableChunks $handlerInstance) {
  47                 // Get new instance
  48                 $decoderInstance = new PackageDecoder();
  49
  50                 // Init stacker for received packages
  51                 $handlerInstance->getStackInstance()->initStack(self::STACKER_NAME_DECODED_PACKAGE);
  52
  53                 // Set the handler instance here
  54                 $decoderInstance->setHandlerInstance($handlerInstance);
  55
  56                 // Get a singleton network package instance
  57                 $packageInstance = NetworkPackageFactory::createNetworkPackageInstance();
  58
  59                 // And set it in this decoder
  60                 $decoderInstance->setPackageInstance($packageInstance);
  61
  62                 // Return the prepared instance
  63                 return $decoderInstance;
  64         }
  65
  66         /**
  67          * Checks whether the assoziated stacker for raw package data has some entries left
  68          *
  69          * @return      $unhandledDataLeft      Whether some unhandled raw package data is left
  70          */
  71         public function ifUnhandledRawPackageDataLeft () {
  72                 // Check it
  73                 $unhandledDataLeft = (!$this->getHandlerInstance()->getStackInstance()->isStackEmpty(ChunkHandler::STACKER_NAME_ASSEMBLED_RAW_DATA));
  74
  75                 // Return it
  76                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PACKAGE-DECODER[' . __METHOD__ . ':' . __LINE__ . ']: unhandledDataLeft=' . intval($unhandledDataLeft));
  77                 return $unhandledDataLeft;
  78         }
  79
  80         /**
  81          * Handles raw package data by decoding it
  82          *
  83          * @return      void
  84          */
  85         public function handleRawPackageData () {
  86                 // Assert on it to make sure the next popNamed() call won't throw an exception
  87                 assert($this->ifUnhandledRawPackageDataLeft());
  88
  89                 // "Pop" the next raw package content
  90                 $rawPackageContent = $this->getHandlerInstance()->getStackInstance()->popNamed(ChunkHandler::STACKER_NAME_ASSEMBLED_RAW_DATA);
  91
  92                 // Debug message
  93                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PACKAGE-DECODER[' . __METHOD__ . ':' . __LINE__ . ']: Got ' . strlen($rawPackageContent) . ' bytes from stack ' . ChunkHandler::STACKER_NAME_ASSEMBLED_RAW_DATA . ', decoding it ...');
  94
  95                 // "Decode" the raw package content by using the NetworkPackage instance
  96                 $decodedData = $this->getPackageInstance()->decodeRawContent($rawPackageContent);
  97
  98                 // Some checks
  99                 assert(
 100                         (is_array($decodedData)) &&
 101                         (isset($decodedData[NetworkPackage::PACKAGE_DATA_SENDER])) &&
 102                         (isset($decodedData[NetworkPackage::PACKAGE_DATA_RECIPIENT])) &&
 103                         (isset($decodedData[NetworkPackage::PACKAGE_DATA_CONTENT])) &&
 104                         (isset($decodedData[NetworkPackage::PACKAGE_DATA_STATUS]))
 105                 );
 106
 107                 // Debug message
 108                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PACKAGE-DECODER[' . __METHOD__ . ':' . __LINE__ . ']: decodedData(' . count($decodedData) . ')=' . print_r($decodedData, TRUE));
 109
 110                 // Next get a recipient-discovery instance
 111                 $discoveryInstance = PackageDiscoveryFactory::createPackageDiscoveryInstance();
 112
 113                 // ... then disover all recipient (might be only one), this package may shall be forwarded
 114                 $discoveryInstance->discoverRawRecipients($decodedData);
 115
 116                 // Check for 'recipient' field (the 'sender' field and others are ignored here)
 117                 if ($discoveryInstance->isRecipientListEmpty()) {
 118                         // The recipient is this node so next stack it on 'decoded_package'
 119                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PACKAGE-DECODER[' . __METHOD__ . ':' . __LINE__ . ']: Pushing ' . strlen($decodedData) . ' bytes to stack ' . self::STACKER_NAME_DECODED_PACKAGE . ' ...');
 120                         $this->getHandlerInstance()->getStackInstance()->pushNamed(self::STACKER_NAME_DECODED_PACKAGE, $decodedData);
 121                 } else {
 122                         // Forward the package to the next node
 123                         $this->getPackageInstance()->forwardRawPackage($decodedData);
 124                 }
 125         }
 126
 127         /**
 128          * Checks whether decoded packages have arrived (for this peer)
 129          *
 130          * @return      $ifRawPackagesLeft      Whether decoded packages have arrived
 131          */
 132         public function ifDeocedPackagesLeft () {
 133                 // Check it ...
 134                 $ifRawPackagesLeft = (!$this->getHandlerInstance()->getStackInstance()->isStackEmpty(self::STACKER_NAME_DECODED_PACKAGE));
 135
 136                 // ... return it
 137                 return $ifRawPackagesLeft;
 138         }
 139
 140         /**
 141          * Handles received decoded packages internally (recipient is this node)
 142          *
 143          * @return      void
 144          */
 145         public function handleDecodedPackage () {
 146                 // Assert on amount
 147                 assert($this->ifDeocedPackagesLeft());
 148
 149                 // Get the next entry (assoziative array)
 150                 $decodedData = $this->getHandlerInstance()->getStackInstance()->popNamed(self::STACKER_NAME_DECODED_PACKAGE);
 151
 152                 // Handle it
 153                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('PACKAGE-DECODER[' . __METHOD__ . ':' . __LINE__ . ']: decodedData(' . count($decodedData) . ')=' . print_r($decodedData, TRUE));
 154                 $this->getPackageInstance()->handleRawData($decodedData);
 155         }
 156 }
 157
 158 // [EOF]
 159 ?>