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\Generic\EmptyVariableException;
  10 use CoreFramework\Request\Requestable;
  11 use CoreFramework\Resolver\BaseResolver;
  12
  13 /**
  14  * A generic command resolver class
  15  *
  16  * @author              Roland Haeder <webmaster@shipsimu.org>
  17  * @version             0.0.0
  18  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  19  * @license             GNU GPL 3.0 or any newer version
  20  * @link                http://www.shipsimu.org
  21  *
  22  * This program is free software: you can redistribute it and/or modify
  23  * it under the terms of the GNU General Public License as published by
  24  * the Free Software Foundation, either version 3 of the License, or
  25  * (at your option) any later version.
  26  *
  27  * This program is distributed in the hope that it will be useful,
  28  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  29  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  30  * GNU General Public License for more details.
  31  *
  32  * You should have received a copy of the GNU General Public License
  33  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  34  */
  35 class BaseCommandResolver extends BaseResolver {
  36         /**
  37          * Protected constructor
  38          *
  39          * @param       $className      Name of the class
  40          * @return      void
  41          */
  42         protected function __construct ($className) {
  43                 // Call parent constructor
  44                 parent::__construct($className);
  45         }
  46
  47         /**
  48          * "Loads" a given command and instances it if not yet cached
  49          *
  50          * @param       $commandName                            A command name we shall look for
  51          * @return      $commandInstance                        A loaded command instance
  52          * @throws      InvalidCommandException         Thrown if even the default
  53          *                                                                              command class is missing (bad!)
  54          */
  55         protected function loadCommand ($commandName) {
  56                 // Init command instance
  57                 $commandInstance = NULL;
  58
  59                 // Create class name
  60                 $className = sprintf(
  61                         '%s\%s%sCommand',
  62                         $this->getNamespace(),
  63                         $this->getCapitalizedClassPrefix(),
  64                         self::convertToClassName($commandName)
  65                 );
  66
  67                 // Create command class name
  68                 $this->setClassName($className);
  69
  70                 // Is this class loaded?
  71                 if (!class_exists($this->getClassName())) {
  72                         // Class not found, so throw an exception
  73                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
  74                 } // END - if
  75
  76                 // Initiate the command
  77                 $commandInstance = ObjectFactory::createObjectByName($this->getClassName(), array($this));
  78
  79                 // Return the result
  80                 return $commandInstance;
  81         }
  82
  83         /**
  84          * Returns an command instance for a given request class or null if
  85          * it was not found
  86          *
  87          * @param       $requestInstance        An instance of a Requestable class
  88          * @return      $commandInstance        An instance of the resolved command
  89          * @throws      InvalidCommandException                         Thrown if $commandName is
  90          *                                                                                              invalid
  91          * @throws      InvalidCommandInstanceException         Thrown if $commandInstance
  92          *                                                                                              is an invalid instance
  93          */
  94         public function resolveCommandByRequest (Requestable $requestInstance) {
  95                 // Init variables
  96                 $commandName = '';
  97                 $commandInstance = NULL;
  98
  99                 // This goes fine so let's resolve the command
 100                 $commandName = $requestInstance->getRequestElement('command');
 101
 102                 // Is the command empty? Then fall back to default command
 103                 if (empty($commandName)) {
 104                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
 105                 } // END - if
 106
 107                 // Check if command is valid
 108                 if ($this->isCommandValid($this->getNamespace(), $commandName) === FALSE) {
 109                         // This command is invalid!
 110                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 111                 } // END - if
 112
 113                 // Get the command
 114                 $commandInstance = $this->loadCommand($commandName);
 115
 116                 // And validate it
 117                 if ((!is_object($commandInstance)) || (!$commandInstance instanceof Commandable)) {
 118                         // This command has an invalid instance!
 119                         throw new InvalidCommandInstanceException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 120                 } // END - if
 121
 122                 // Set last command
 123                 $this->setResolvedInstance($commandInstance);
 124
 125                 // Return the resolved command instance
 126                 return $commandInstance;
 127         }
 128
 129         /**
 130          * Resolves the command by its direct name and returns an instance of its class
 131          *
 132          * @param       $commandName            The direct command name we shall resolve
 133          * @return      $commandInstance        An instance of the command class
 134          * @throws      InvalidCommandException         Thrown if $commandName is invalid
 135          */
 136         public function resolveCommand ($commandName) {
 137                 // Initiate the instance variable
 138                 $commandInstance = NULL;
 139
 140                 // Is the command empty? Then fall back to default command
 141                 if (empty($commandName)) {
 142                         $commandName = $this->getConfigInstance()->getConfigEntry('default_' . self::getResponseTypeFromSystem() . '_command');
 143                 } // END - if
 144
 145                 // Check if command is valid
 146                 if ($this->isCommandValid($commandName) === FALSE) {
 147                         // This command is invalid!
 148                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 149                 } // END - if
 150
 151                 // Get the command
 152                 $commandInstance = $this->loadCommand($commandName);
 153
 154                 // Return the instance
 155                 return $commandInstance;
 156         }
 157
 158         /**
 159          * Checks whether the given command is valid
 160          *
 161          * @param       $namespace              Namespace to look in
 162          * @param       $commandName    The default command we shall execute
 163          * @return      $isValid                Whether the given command is valid
 164          * @throws      EmptyVariableException  Thrown if given command is not set
 165          */
 166         protected function isCommandValid ($namespace, $commandName) {
 167                 // By default nothing shall be valid
 168                 $isValid = FALSE;
 169
 170                 // Is namespace and command name set?
 171                 if (empty($namespace)) {
 172                         // Then thrown an exception here
 173                         throw new EmptyVariableException(array($this, 'namespace'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
 174                 } elseif (empty($commandName)) {
 175                         // Then thrown an exception here
 176                         throw new EmptyVariableException(array($this, 'commandName'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
 177                 } // END - if
 178
 179                 // Create the full class name
 180                 $className = sprintf(
 181                         '%s\%s%sCommand',
 182                         $namespace,
 183                         $this->getCapitalizedClassPrefix(),
 184                         self::convertToClassName($commandName)
 185                 );
 186
 187                 // Now, let us create the full name of the command class
 188                 $this->setClassName($className);
 189
 190                 // Is this class already loaded?
 191                 if (class_exists($this->getClassName())) {
 192                         // This class does exist. :-)
 193                         $isValid = TRUE;
 194                 } // END - if
 195
 196                 // Set command name
 197                 $this->setCommandName($commandName);
 198
 199                 // Return the result
 200                 return $isValid;
 201         }
 202
 203 }