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 use CoreFramework\Resolver\BaseResolver;
   9
  10 /**
  11  * A generic command resolver class
  12  *
  13  * @author              Roland Haeder <webmaster@shipsimu.org>
  14  * @version             0.0.0
  15  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  16  * @license             GNU GPL 3.0 or any newer version
  17  * @link                http://www.shipsimu.org
  18  *
  19  * This program is free software: you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation, either version 3 of the License, or
  22  * (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  31  */
  32 class BaseCommandResolver extends BaseResolver {
  33         /**
  34          * Protected constructor
  35          *
  36          * @param       $className      Name of the class
  37          * @return      void
  38          */
  39         protected function __construct ($className) {
  40                 // Call parent constructor
  41                 parent::__construct($className);
  42         }
  43
  44         /**
  45          * "Loads" a given command and instances it if not yet cached
  46          *
  47          * @param       $commandName                            A command name we shall look for
  48          * @return      $commandInstance                        A loaded command instance
  49          * @throws      InvalidCommandException         Thrown if even the default
  50          *                                                                              command class is missing (bad!)
  51          */
  52         protected function loadCommand ($commandName) {
  53                 // Init command instance
  54                 $commandInstance = NULL;
  55
  56                 // Create class name
  57                 $className = $this->getCapitalizedClassPrefix() . self::convertToClassName($commandName) . 'Command';
  58
  59                 // Create command class name
  60                 $this->setClassName($className);
  61
  62                 // Is this class loaded?
  63                 if (!class_exists($this->getClassName())) {
  64                         // Class not found, so throw an exception
  65                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
  66                 } // END - if
  67
  68                 // Initiate the command
  69                 $commandInstance = ObjectFactory::createObjectByName($this->getClassName(), array($this));
  70
  71                 // Return the result
  72                 return $commandInstance;
  73         }
  74
  75         /**
  76          * Returns an command instance for a given request class or null if
  77          * it was not found
  78          *
  79          * @param       $requestInstance        An instance of a Requestable class
  80          * @return      $commandInstance        An instance of the resolved command
  81          * @throws      InvalidCommandException                         Thrown if $commandName is
  82          *                                                                                              invalid
  83          * @throws      InvalidCommandInstanceException         Thrown if $commandInstance
  84          *                                                                                              is an invalid instance
  85          */
  86         public function resolveCommandByRequest (Requestable $requestInstance) {
  87                 // Init variables
  88                 $commandName = '';
  89                 $commandInstance = NULL;
  90
  91                 // This goes fine so let's resolve the command
  92                 $commandName = $requestInstance->getRequestElement('command');
  93
  94                 // Is the command empty? Then fall back to default command
  95                 if (empty($commandName)) {
  96                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
  97                 } // END - if
  98
  99                 // Check if command is valid
 100                 if ($this->isCommandValid($commandName) === FALSE) {
 101                         // This command is invalid!
 102                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 103                 } // END - if
 104
 105                 // Get the command
 106                 $commandInstance = $this->loadCommand($commandName);
 107
 108                 // And validate it
 109                 if ((!is_object($commandInstance)) || (!$commandInstance instanceof Commandable)) {
 110                         // This command has an invalid instance!
 111                         throw new InvalidCommandInstanceException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 112                 } // END - if
 113
 114                 // Set last command
 115                 $this->setResolvedInstance($commandInstance);
 116
 117                 // Return the resolved command instance
 118                 return $commandInstance;
 119         }
 120
 121         /**
 122          * Resolves the command by its direct name and returns an instance of its class
 123          *
 124          * @param       $commandName            The direct command name we shall resolve
 125          * @return      $commandInstance        An instance of the command class
 126          * @throws      InvalidCommandException         Thrown if $commandName is invalid
 127          */
 128         public function resolveCommand ($commandName) {
 129                 // Initiate the instance variable
 130                 $commandInstance = NULL;
 131
 132                 // Is the command empty? Then fall back to default command
 133                 if (empty($commandName)) {
 134                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
 135                 } // END - if
 136
 137                 // Check if command is valid
 138                 if ($this->isCommandValid($commandName) === FALSE) {
 139                         // This command is invalid!
 140                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 141                 } // END - if
 142
 143                 // Get the command
 144                 $commandInstance = $this->loadCommand($commandName);
 145
 146                 // Return the instance
 147                 return $commandInstance;
 148         }
 149
 150         /**
 151          * Checks whether the given command is valid
 152          *
 153          * @param       $commandName    The default command we shall execute
 154          * @return      $isValid                Whether the given command is valid
 155          * @throws      EmptyVariableException  Thrown if given command is not set
 156          */
 157         public function isCommandValid ($commandName) {
 158                 // By default nothing shall be valid
 159                 $isValid = FALSE;
 160
 161                 // Is a command set?
 162                 if (empty($commandName)) {
 163                         // Then thrown an exception here
 164                         throw new EmptyVariableException(array($this, 'commandName'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
 165                 } // END - if
 166
 167                 // Create the full class name
 168                 $className = $this->getCapitalizedClassPrefix() . self::convertToClassName($commandName) . 'Command';
 169
 170                 // Now, let us create the full name of the command class
 171                 $this->setClassName($className);
 172
 173                 // Is this class already loaded?
 174                 if (class_exists($this->getClassName())) {
 175                         // This class does exist. :-)
 176                         $isValid = TRUE;
 177                 } // END - if
 178
 179                 // Set command name
 180                 $this->setCommandName($commandName);
 181
 182                 // Return the result
 183                 return $isValid;
 184         }
 185
 186 }