Host name fixed (a redirect causes an error), duplicate code rewrriten to be more...
[core.git] / inc / classes / main / resolver / command / web / class_WebCommandResolver.php
1 <?php
2 /**
3  * A command resolver for local (non-hubbed) web commands
4  *
5  * @author              Roland Haeder <webmaster@ship-simu.org>
6  * @version             0.0.0
7  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009, 2010 Core Developer Team
8  * @license             GNU GPL 3.0 or any newer version
9  * @link                http://www.ship-simu.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 WebCommandResolver extends BaseCommandResolver implements CommandResolver {
25         /**
26          * Last successfull resolved command
27          */
28         private $lastCommandInstance = null;
29
30         /**
31          * Protected constructor
32          *
33          * @return      void
34          */
35         protected function __construct () {
36                 // Call parent constructor
37                 parent::__construct(__CLASS__);
38
39                 // Set prefix to "Web"
40                 $this->setClassPrefix('Web');
41         }
42
43         /**
44          * Creates an instance of a Web command resolver with a given default command
45          *
46          * @param       $commandName                            The default command we shall execute
47          * @param       $appInstance                            An instance of a manageable application helper class
48          * @return      $resolverInstance                       The prepared command resolver instance
49          * @throws      EmptyVariableException          Thrown if default command is not set
50          * @throws      InvalidCommandException         Thrown if default command is invalid
51          */
52         public static final function createWebCommandResolver ($commandName, ManageableApplication $appInstance) {
53                 // Create the new instance
54                 $resolverInstance = new WebCommandResolver();
55
56                 // Is the variable $commandName set and the command is valid?
57                 if (empty($commandName)) {
58                         // Then thrown an exception here
59                         throw new EmptyVariableException(array($resolverInstance, 'commandName'), self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
60                 } elseif ($resolverInstance->isCommandValid($commandName) === false) {
61                         // Invalid command found
62                         throw new InvalidCommandException(array($resolverInstance, $commandName), self::EXCEPTION_INVALID_COMMAND);
63                 }
64
65                 // Set the application instance
66                 $resolverInstance->setApplicationInstance($appInstance);
67
68                 // Return the prepared instance
69                 return $resolverInstance;
70         }
71
72         /**
73          * Returns an command instance for a given request class or null if
74          * it was not found
75          *
76          * @param       $requestInstance        An instance of a request class
77          * @return      $commandInstance        An instance of the resolved command
78          * @throws      InvalidCommandException                         Thrown if $commandName is
79          *                                                                                              invalid
80          * @throws      InvalidCommandInstanceException         Thrown if $commandInstance
81          *                                                                                              is an invalid instance
82          */
83         public function resolveCommandByRequest (Requestable $requestInstance) {
84                 // Init variables
85                 $commandName = '';
86                 $commandInstance = null;
87
88                 // This goes fine so let's resolve the command
89                 $commandName = $requestInstance->getRequestElement('page');
90
91                 // Is the command empty? Then fall back to default command
92                 if (empty($commandName)) {
93                         $commandName = $this->getConfigInstance()->getConfigEntry('default_web_command');
94                 } // END - if
95
96                 // Check if command is valid
97                 if ($this->isCommandValid($commandName) === false) {
98                         // This command is invalid!
99                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
100                 } // END - if
101
102                 // Get the command
103                 $commandInstance = $this->loadCommand($commandName);
104
105                 // And validate it
106                 if ((!is_object($commandInstance)) || (!$commandInstance instanceof Commandable)) {
107                         // This command has an invalid instance!
108                         throw new InvalidCommandInstanceException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
109                 } // END - if
110
111                 // Set last command
112                 $this->setResolvedInstance($commandInstance);
113
114                 // Return the resolved command instance
115                 return $commandInstance;
116         }
117
118         /**
119          * Resolves the command by its direct name and returns an instance of its class
120          *
121          * @param       $commandName            The direct command name we shall resolve
122          * @return      $commandInstance        An instance of the command class
123          * @throws      InvalidCommandException         Thrown if $commandName is invalid
124          */
125         public function resolveCommand ($commandName) {
126                 // Initiate the instance variable
127                 $commandInstance = null;
128
129                 // Is the command empty? Then fall back to default command
130                 if (empty($commandName)) {
131                         $commandName = $this->getConfigInstance()->getConfigEntry('default_web_command');
132                 } // END - if
133
134                 // Check if command is valid
135                 if ($this->isCommandValid($commandName) === false) {
136                         // This command is invalid!
137                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
138                 } // END - if
139
140                 // Get the command
141                 $commandInstance = $this->loadCommand($commandName);
142
143                 // Return the instance
144                 return $commandInstance;
145         }
146
147         /**
148          * "Loads" a given command and instances it if not yet cached
149          *
150          * @param       $commandName                            A command name we shall look for
151          * @return      $commandInstance                        A loaded command instance
152          * @throws      InvalidCommandException         Thrown if even the default
153          *                                                                              command class is missing (bad!)
154          */
155         private function loadCommand ($commandName) {
156                 // Init command instance
157                 $commandInstance = null;
158
159                 // Is this class loaded?
160                 if (!class_exists($this->getClassName())) {
161                         // Class not found, so throw an exception
162                         throw new InvalidCommandException(array($this, $commandName), self::EXCEPTION_INVALID_COMMAND);
163                 } // END - if
164
165                 // Initiate the command
166                 $commandInstance = ObjectFactory::createObjectByName($this->getClassName(), array($this));
167
168                 // Return the result
169                 return $commandInstance;
170         }
171 }
172
173 // [EOF]
174 ?>