includes/skins/SkinFactory.php

   1 <?php
   2
   3 /**
   4  * Copyright 2014
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  * http://www.gnu.org/copyleft/gpl.html
  20  *
  21  * @file
  22  */
  23
  24 /**
  25  * Factory class to create Skin objects
  26  *
  27  * @since 1.24
  28  */
  29 class SkinFactory {
  30
  31         /**
  32          * Map of name => callback
  33          * @var array
  34          */
  35         private $factoryFunctions = array();
  36         /**
  37          * Map of name => fallback human-readable name, used when the 'skinname-<skin>' message is not
  38          * available
  39          *
  40          * @var array
  41          */
  42         private $displayNames = array();
  43
  44         /**
  45          * @var SkinFactory
  46          */
  47         private static $self;
  48
  49         public static function getDefaultInstance() {
  50                 if ( !self::$self ) {
  51                         self::$self = new self;
  52                 }
  53
  54                 return self::$self;
  55         }
  56
  57         /**
  58          * Register a new Skin factory function.
  59          *
  60          * Will override if it's already registered.
  61          *
  62          * @param string $name Internal skin name. Should be all-lowercase (technically doesn't have
  63          *     to be, but doing so would change the case of i18n message keys).
  64          * @param string $displayName For backwards-compatibility with old skin loading system. This is
  65          *     the text used as skin's human-readable name when the 'skinname-<skin>' message is not
  66          *     available. It should be the same as the skin name provided in $wgExtensionCredits.
  67          * @param callable $callback Callback that takes the skin name as an argument
  68          * @throws InvalidArgumentException If an invalid callback is provided
  69          */
  70         public function register( $name, $displayName, $callback ) {
  71                 if ( !is_callable( $callback ) ) {
  72                         throw new InvalidArgumentException( 'Invalid callback provided' );
  73                 }
  74                 $this->factoryFunctions[$name] = $callback;
  75                 $this->displayNames[$name] = $displayName;
  76         }
  77
  78         /**
  79          * Returns an associative array of:
  80          *  skin name => human readable name
  81          *
  82          * @return array
  83          */
  84         public function getSkinNames() {
  85                 return $this->displayNames;
  86         }
  87
  88         /**
  89          * Create a given Skin using the registered callback for $name.
  90          * @param string $name Name of the skin you want
  91          * @throws SkinException If a factory function isn't registered for $name
  92          * @throws UnexpectedValueException If the factory function returns a non-Skin object
  93          * @return Skin
  94          */
  95         public function makeSkin( $name ) {
  96                 if ( !isset( $this->factoryFunctions[$name] ) ) {
  97                         throw new SkinException( "No registered builder available for $name." );
  98                 }
  99                 $skin = call_user_func( $this->factoryFunctions[$name], $name );
 100                 if ( $skin instanceof Skin ) {
 101                         return $skin;
 102                 } else {
 103                         throw new UnexpectedValueException( "The builder for $name returned a non-Skin object." );
 104                 }
 105         }
 106 }