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

   1 <?php
   2 /**
   3  * A generic command resolver class
   4  *
   5  * @author              Roland Haeder <webmaster@shipsimu.org>
   6  * @version             0.0.0
   7  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 Core Developer Team
   8  * @license             GNU GPL 3.0 or any newer version
   9  * @link                http://www.shipsimu.org
  10  *
  11  * This program is free software: you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation, either version 3 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  23  */
  24 class BaseCommandResolver extends BaseResolver {
  25         /**
  26          * Validated command name
  27          */
  28         private $commandName = '';
  29
  30         /**
  31          * Protected constructor
  32          *
  33          * @param       $className      Name of the class
  34          * @return      void
  35          */
  36         protected function __construct ($className) {
  37                 // Call parent constructor
  38                 parent::__construct($className);
  39         }
  40
  41         /**
  42          * Setter for command name
  43          *
  44          * @param       $commandName    Last validated command name
  45          * @return      void
  46          */
  47         protected final function setCommandName ($commandName) {
  48                 $this->commandName = $commandName;
  49         }
  50
  51         /**
  52          * Getter for command name
  53          *
  54          * @return      $commandName    Last validated command name
  55          */
  56         protected final function getCommandName () {
  57                 return $this->commandName;
  58         }
  59
  60         /**
  61          * "Loads" a given command and instances it if not yet cached
  62          *
  63          * @param       $commandName                            A command name we shall look for
  64          * @return      $commandInstance                        A loaded command instance
  65          * @throws      InvalidCommandException         Thrown if even the default
  66          *                                                                              command class is missing (bad!)
  67          */
  68         protected function loadCommand ($commandName) {
  69                 // Init command instance
  70                 $commandInstance = NULL;
  71
  72                 // Create class name
  73                 $className = $this->getCapitalizedClassPrefix() . $this->convertToClassName($commandName) . 'Command';
  74
  75                 // Create command class name
  76                 $this->setClassName($className);
  77
  78                 // Is this class loaded?
  79                 if (!class_exists($this->getClassName())) {
  80                         // Class not found, so throw an exception
  81                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
  82                 } // END - if
  83
  84                 // Initiate the command
  85                 $commandInstance = ObjectFactory::createObjectByName($this->getClassName(), array($this));
  86
  87                 // Return the result
  88                 return $commandInstance;
  89         }
  90
  91         /**
  92          * Returns an command instance for a given request class or null if
  93          * it was not found
  94          *
  95          * @param       $requestInstance        An instance of a request class
  96          * @return      $commandInstance        An instance of the resolved command
  97          * @throws      InvalidCommandException                         Thrown if $commandName is
  98          *                                                                                              invalid
  99          * @throws      InvalidCommandInstanceException         Thrown if $commandInstance
 100          *                                                                                              is an invalid instance
 101          */
 102         public function resolveCommandByRequest (Requestable $requestInstance) {
 103                 // Init variables
 104                 $commandName = '';
 105                 $commandInstance = NULL;
 106
 107                 // This goes fine so let's resolve the command
 108                 $commandName = $requestInstance->getRequestElement('command');
 109
 110                 // Is the command empty? Then fall back to default command
 111                 if (empty($commandName)) {
 112                         $commandName = $this->getConfigInstance()->getConfigEntry('default_html_command');
 113                 } // END - if
 114
 115                 // Check if command is valid
 116                 if ($this->isCommandValid($commandName) === FALSE) {
 117                         // This command is invalid!
 118                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 119                 } // END - if
 120
 121                 // Get the command
 122                 $commandInstance = $this->loadCommand($commandName);
 123
 124                 // And validate it
 125                 if ((!is_object($commandInstance)) || (!$commandInstance instanceof Commandable)) {
 126                         // This command has an invalid instance!
 127                         throw new InvalidCommandInstanceException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 128                 } // END - if
 129
 130                 // Set last command
 131                 $this->setResolvedInstance($commandInstance);
 132
 133                 // Return the resolved command instance
 134                 return $commandInstance;
 135         }
 136
 137         /**
 138          * Resolves the command by its direct name and returns an instance of its class
 139          *
 140          * @param       $commandName            The direct command name we shall resolve
 141          * @return      $commandInstance        An instance of the command class
 142          * @throws      InvalidCommandException         Thrown if $commandName is invalid
 143          */
 144         public function resolveCommand ($commandName) {
 145                 // Initiate the instance variable
 146                 $commandInstance = NULL;
 147
 148                 // Is the command empty? Then fall back to default command
 149                 if (empty($commandName)) {
 150                         $commandName = $this->getConfigInstance()->getConfigEntry('default_html_command');
 151                 } // END - if
 152
 153                 // Check if command is valid
 154                 if ($this->isCommandValid($commandName) === FALSE) {
 155                         // This command is invalid!
 156                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
 157                 } // END - if
 158
 159                 // Get the command
 160                 $commandInstance = $this->loadCommand($commandName);
 161
 162                 // Return the instance
 163                 return $commandInstance;
 164         }
 165
 166         /**
 167          * Checks whether the given command is valid
 168          *
 169          * @param       $commandName    The default command we shall execute
 170          * @return      $isValid                Whether the given command is valid
 171          * @throws      EmptyVariableException  Thrown if given command is not set
 172          */
 173         public function isCommandValid ($commandName) {
 174                 // By default nothing shall be valid
 175                 $isValid = FALSE;
 176
 177                 // Is a command set?
 178                 if (empty($commandName)) {
 179                         // Then thrown an exception here
 180                         throw new EmptyVariableException(array($this, 'commandName'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
 181                 } // END - if
 182
 183                 // Create the full class name
 184                 $className = $this->getCapitalizedClassPrefix() . $this->convertToClassName($commandName) . 'Command';
 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
 203 // [EOF]
 204 ?>