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