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

   1 <?php
   2 // Own namespace
   3 namespace CoreFramework\Resolver\Command;
   4
   5 // Import framework stuff
   6 use CoreFramework\Command\Commandable;
   7 use CoreFramework\Command\InvalidCommandException;
   8 use CoreFramework\Factory\ObjectFactory;
   9 use CoreFramework\Request\Requestable;
  10 use CoreFramework\Resolver\BaseResolver;
  11
  12 /**
  13  * A generic command resolver class
  14  *
  15  * @author              Roland Haeder <webmaster@shipsimu.org>
  16  * @version             0.0.0
  17  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  18  * @license             GNU GPL 3.0 or any newer version
  19  * @link                http://www.shipsimu.org
  20  *
  21  * This program is free software: you can redistribute it and/or modify
  22  * it under the terms of the GNU General Public License as published by
  23  * the Free Software Foundation, either version 3 of the License, or
  24  * (at your option) any later version.
  25  *
  26  * This program is distributed in the hope that it will be useful,
  27  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  29  * GNU General Public License for more details.
  30  *
  31  * You should have received a copy of the GNU General Public License
  32  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  33  */
  34 class BaseCommandResolver extends BaseResolver {
  35         /**
  36          * Protected constructor
  37          *
  38          * @param       $className      Name of the class
  39          * @return      void
  40          */
  41         protected function __construct ($className) {
  42                 // Call parent constructor
  43                 parent::__construct($className);
  44         }
  45
  46         /**
  47          * "Loads" a given command and instances it if not yet cached
  48          *
  49          * @param       $commandName                            A command name we shall look for
  50          * @return      $commandInstance                        A loaded command instance
  51          * @throws      InvalidCommandException         Thrown if even the default
  52          *                                                                              command class is missing (bad!)
  53          */
  54         protected function loadCommand ($commandName) {
  55                 // Init command instance
  56                 $commandInstance = NULL;
  57
  58                 // Create class name
  59                 $className = sprintf(
  60                         '%s\%s%sCommand',
  61                         $this->getNamespace(),
  62                         $this->getCapitalizedClassPrefix(),
  63                         self::convertToClassName($commandName)
  64                 );
  65
  66                 // Create command class name
  67                 $this->setClassName($className);
  68
  69                 // Is this class loaded?
  70                 if (!class_exists($this->getClassName())) {
  71                         // Class not found, so throw an exception
  72                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
  73                 } // END - if
  74
  75                 // Initiate the command
  76                 $commandInstance = ObjectFactory::createObjectByName($this->getClassName(), array($this));
  77
  78                 // Return the result
  79                 return $commandInstance;
  80         }
  81
  82         /**
  83          * Returns an command instance for a given request class or null if
  84          * it was not found
  85          *
  86          * @param       $requestInstance        An instance of a Requestable class
  87          * @return      $commandInstance        An instance of the resolved command
  88          * @throws      InvalidCommandException                         Thrown if $commandName is
  89          *                                                                                              invalid
  90          * @throws      InvalidCommandInstanceException         Thrown if $commandInstance
  91          *                                                                                              is an invalid instance
  92          */
  93         public function resolveCommandByRequest (Requestable $requestInstance) {
  94                 // Init variables
  95                 $commandName = '';
  96                 $commandInstance = NULL;
  97
  98                 // This goes fine so let's resolve the command
  99                 $commandName = $requestInstance->getRequestElement('command');
 100
 101                 // Is the command empty? Then fall back to default command
 102                 if (empty($commandName)) {
 103                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
 104                 } // END - if
 105
 106                 // Check if command is valid
 107                 if ($this->isCommandValid($commandName) === FALSE) {
 108                         // This command is invalid!
 109                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 110                 } // END - if
 111
 112                 // Get the command
 113                 $commandInstance = $this->loadCommand($commandName);
 114
 115                 // And validate it
 116                 if ((!is_object($commandInstance)) || (!$commandInstance instanceof Commandable)) {
 117                         // This command has an invalid instance!
 118                         throw new InvalidCommandInstanceException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 119                 } // END - if
 120
 121                 // Set last command
 122                 $this->setResolvedInstance($commandInstance);
 123
 124                 // Return the resolved command instance
 125                 return $commandInstance;
 126         }
 127
 128         /**
 129          * Resolves the command by its direct name and returns an instance of its class
 130          *
 131          * @param       $commandName            The direct command name we shall resolve
 132          * @return      $commandInstance        An instance of the command class
 133          * @throws      InvalidCommandException         Thrown if $commandName is invalid
 134          */
 135         public function resolveCommand ($commandName) {
 136                 // Initiate the instance variable
 137                 $commandInstance = NULL;
 138
 139                 // Is the command empty? Then fall back to default command
 140                 if (empty($commandName)) {
 141                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
 142                 } // END - if
 143
 144                 // Check if command is valid
 145                 if ($this->isCommandValid($commandName) === FALSE) {
 146                         // This command is invalid!
 147                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 148                 } // END - if
 149
 150                 // Get the command
 151                 $commandInstance = $this->loadCommand($commandName);
 152
 153                 // Return the instance
 154                 return $commandInstance;
 155         }
 156
 157         /**
 158          * Checks whether the given command is valid
 159          *
 160          * @param       $namespace              Namespace to look in
 161          * @param       $commandName    The default command we shall execute
 162          * @return      $isValid                Whether the given command is valid
 163          * @throws      EmptyVariableException  Thrown if given command is not set
 164          */
 165         protected function isCommandValid ($namespace, $commandName) {
 166                 // By default nothing shall be valid
 167                 $isValid = FALSE;
 168
 169                 // Is namespace and command name set?
 170                 if (empty($namespace)) {
 171                         // Then thrown an exception here
 172                         throw new EmptyVariableException(array($this, 'namespace'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
 173                 } elseif (empty($commandName)) {
 174                         // Then thrown an exception here
 175                         throw new EmptyVariableException(array($this, 'commandName'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
 176                 } // END - if
 177
 178                 // Create the full class name
 179                 $className = sprintf(
 180                         '%s\%s%sCommand',
 181                         $namespace,
 182                         $this->getCapitalizedClassPrefix(),
 183                         self::convertToClassName($commandName)
 184                 );
 185
 186                 // Now, let us create the full name of the command class
 187                 $this->setClassName($className);
 188
 189                 // Is this class already loaded?
 190                 if (class_exists($this->getClassName())) {
 191                         // This class does exist. :-)
 192                         $isValid = TRUE;
 193                 } // END - if
 194
 195                 // Set command name
 196                 $this->setCommandName($commandName);
 197
 198                 // Return the result
 199                 return $isValid;
 200         }
 201
 202 }