inc/main/classes/resolver/command/class_BaseCommandResolver.php

   1 <?php
   2 // Own namespace
   3 namespace CoreFramework\Resolver\Controller;
   4
   5 // Import framework stuff
   6 use CoreFramework\Factory\ObjectFactory;
   7 use CoreFramework\Request\Requestable;
   8
   9 /**
  10  * A generic command resolver class
  11  *
  12  * @author              Roland Haeder <webmaster@shipsimu.org>
  13  * @version             0.0.0
  14  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  15  * @license             GNU GPL 3.0 or any newer version
  16  * @link                http://www.shipsimu.org
  17  *
  18  * This program is free software: you can redistribute it and/or modify
  19  * it under the terms of the GNU General Public License as published by
  20  * the Free Software Foundation, either version 3 of the License, or
  21  * (at your option) any later version.
  22  *
  23  * This program is distributed in the hope that it will be useful,
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  * GNU General Public License for more details.
  27  *
  28  * You should have received a copy of the GNU General Public License
  29  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  30  */
  31 class BaseCommandResolver extends BaseResolver {
  32         /**
  33          * Protected constructor
  34          *
  35          * @param       $className      Name of the class
  36          * @return      void
  37          */
  38         protected function __construct ($className) {
  39                 // Call parent constructor
  40                 parent::__construct($className);
  41         }
  42
  43         /**
  44          * "Loads" a given command and instances it if not yet cached
  45          *
  46          * @param       $commandName                            A command name we shall look for
  47          * @return      $commandInstance                        A loaded command instance
  48          * @throws      InvalidCommandException         Thrown if even the default
  49          *                                                                              command class is missing (bad!)
  50          */
  51         protected function loadCommand ($commandName) {
  52                 // Init command instance
  53                 $commandInstance = NULL;
  54
  55                 // Create class name
  56                 $className = $this->getCapitalizedClassPrefix() . self::convertToClassName($commandName) . 'Command';
  57
  58                 // Create command class name
  59                 $this->setClassName($className);
  60
  61                 // Is this class loaded?
  62                 if (!class_exists($this->getClassName())) {
  63                         // Class not found, so throw an exception
  64                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
  65                 } // END - if
  66
  67                 // Initiate the command
  68                 $commandInstance = ObjectFactory::createObjectByName($this->getClassName(), array($this));
  69
  70                 // Return the result
  71                 return $commandInstance;
  72         }
  73
  74         /**
  75          * Returns an command instance for a given request class or null if
  76          * it was not found
  77          *
  78          * @param       $requestInstance        An instance of a Requestable class
  79          * @return      $commandInstance        An instance of the resolved command
  80          * @throws      InvalidCommandException                         Thrown if $commandName is
  81          *                                                                                              invalid
  82          * @throws      InvalidCommandInstanceException         Thrown if $commandInstance
  83          *                                                                                              is an invalid instance
  84          */
  85         public function resolveCommandByRequest (Requestable $requestInstance) {
  86                 // Init variables
  87                 $commandName = '';
  88                 $commandInstance = NULL;
  89
  90                 // This goes fine so let's resolve the command
  91                 $commandName = $requestInstance->getRequestElement('command');
  92
  93                 // Is the command empty? Then fall back to default command
  94                 if (empty($commandName)) {
  95                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
  96                 } // END - if
  97
  98                 // Check if command is valid
  99                 if ($this->isCommandValid($commandName) === FALSE) {
 100                         // This command is invalid!
 101                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 102                 } // END - if
 103
 104                 // Get the command
 105                 $commandInstance = $this->loadCommand($commandName);
 106
 107                 // And validate it
 108                 if ((!is_object($commandInstance)) || (!$commandInstance instanceof Commandable)) {
 109                         // This command has an invalid instance!
 110                         throw new InvalidCommandInstanceException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 111                 } // END - if
 112
 113                 // Set last command
 114                 $this->setResolvedInstance($commandInstance);
 115
 116                 // Return the resolved command instance
 117                 return $commandInstance;
 118         }
 119
 120         /**
 121          * Resolves the command by its direct name and returns an instance of its class
 122          *
 123          * @param       $commandName            The direct command name we shall resolve
 124          * @return      $commandInstance        An instance of the command class
 125          * @throws      InvalidCommandException         Thrown if $commandName is invalid
 126          */
 127         public function resolveCommand ($commandName) {
 128                 // Initiate the instance variable
 129                 $commandInstance = NULL;
 130
 131                 // Is the command empty? Then fall back to default command
 132                 if (empty($commandName)) {
 133                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
 134                 } // END - if
 135
 136                 // Check if command is valid
 137                 if ($this->isCommandValid($commandName) === FALSE) {
 138                         // This command is invalid!
 139                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 140                 } // END - if
 141
 142                 // Get the command
 143                 $commandInstance = $this->loadCommand($commandName);
 144
 145                 // Return the instance
 146                 return $commandInstance;
 147         }
 148
 149         /**
 150          * Checks whether the given command is valid
 151          *
 152          * @param       $commandName    The default command we shall execute
 153          * @return      $isValid                Whether the given command is valid
 154          * @throws      EmptyVariableException  Thrown if given command is not set
 155          */
 156         public function isCommandValid ($commandName) {
 157                 // By default nothing shall be valid
 158                 $isValid = FALSE;
 159
 160                 // Is a command set?
 161                 if (empty($commandName)) {
 162                         // Then thrown an exception here
 163                         throw new EmptyVariableException(array($this, 'commandName'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
 164                 } // END - if
 165
 166                 // Create the full class name
 167                 $className = $this->getCapitalizedClassPrefix() . self::convertToClassName($commandName) . 'Command';
 168
 169                 // Now, let us create the full name of the command class
 170                 $this->setClassName($className);
 171
 172                 // Is this class already loaded?
 173                 if (class_exists($this->getClassName())) {
 174                         // This class does exist. :-)
 175                         $isValid = TRUE;
 176                 } // END - if
 177
 178                 // Set command name
 179                 $this->setCommandName($commandName);
 180
 181                 // Return the result
 182                 return $isValid;
 183         }
 184
 185 }