includes/resourceloader/ResourceLoaderImageModule.php

   1 <?php
   2 /**
   3  * Resource loader module for generated and embedded images.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Trevor Parscal
  22  */
  23
  24 /**
  25  * Resource loader module for generated and embedded images.
  26  *
  27  * @since 1.25
  28  */
  29 class ResourceLoaderImageModule extends ResourceLoaderModule {
  30
  31         protected $definition = null;
  32
  33         /**
  34          * Local base path, see __construct()
  35          * @var string
  36          */
  37         protected $localBasePath = '';
  38
  39         protected $origin = self::ORIGIN_CORE_SITEWIDE;
  40
  41         protected $images = array();
  42         protected $variants = array();
  43         protected $prefix = null;
  44         protected $selectorWithoutVariant = '.{prefix}-{name}';
  45         protected $selectorWithVariant = '.{prefix}-{name}-{variant}';
  46         protected $targets = array( 'desktop', 'mobile' );
  47
  48         /** @var string Position on the page to load this module at */
  49         protected $position = 'bottom';
  50
  51         /**
  52          * Constructs a new module from an options array.
  53          *
  54          * @param array $options List of options; if not given or empty, an empty module will be
  55          *     constructed
  56          * @param string $localBasePath Base path to prepend to all local paths in $options. Defaults
  57          *     to $IP
  58          *
  59          * Below is a description for the $options array:
  60          * @par Construction options:
  61          * @code
  62          *     array(
  63          *         // Base path to prepend to all local paths in $options. Defaults to $IP
  64          *         'localBasePath' => [base path],
  65          *         // Path to JSON file that contains any of the settings below
  66          *         'data' => [file path string]
  67          *         // CSS class prefix to use in all style rules
  68          *         'prefix' => [CSS class prefix],
  69          *         // Alternatively: Format of CSS selector to use in all style rules
  70          *         'selector' => [CSS selector template, variables: {prefix} {name} {variant}],
  71          *         // Alternatively: When using variants
  72          *         'selectorWithoutVariant' => [CSS selector template, variables: {prefix} {name}],
  73          *         'selectorWithVariant' => [CSS selector template, variables: {prefix} {name} {variant}],
  74          *         // List of variants that may be used for the image files
  75          *         'variants' => array(
  76          *             [theme name] => array(
  77          *                 [variant name] => array(
  78          *                     'color' => [color string, e.g. '#ffff00'],
  79          *                     'global' => [boolean, if true, this variant is available
  80          *                                  for all images of this type],
  81          *                 ),
  82          *                 ...
  83          *             ),
  84          *             ...
  85          *         ),
  86          *         // List of image files and their options
  87          *         'images' => array(
  88          *             [theme name] => array(
  89          *                 [file path string],
  90          *                 [file path string] => array(
  91          *                     'name' => [image name string, defaults to file name],
  92          *                     'variants' => [array of variant name strings, variants
  93          *                                    available for this image],
  94          *                 ),
  95          *                 ...
  96          *             ),
  97          *             ...
  98          *         ),
  99          *     )
 100          * @endcode
 101          * @throws InvalidArgumentException
 102          */
 103         public function __construct( $options = array(), $localBasePath = null ) {
 104                 $this->localBasePath = self::extractLocalBasePath( $options, $localBasePath );
 105
 106                 $this->definition = $options;
 107         }
 108
 109         /**
 110          * Parse definition and external JSON data, if referenced.
 111          */
 112         protected function loadFromDefinition() {
 113                 if ( $this->definition === null ) {
 114                         return;
 115                 }
 116
 117                 $options = $this->definition;
 118                 $this->definition = null;
 119
 120                 if ( isset( $options['data'] ) ) {
 121                         $dataPath = $this->localBasePath . '/' . $options['data'];
 122                         $data = json_decode( file_get_contents( $dataPath ), true );
 123                         $options = array_merge( $data, $options );
 124                 }
 125
 126                 // Accepted combinations:
 127                 // * prefix
 128                 // * selector
 129                 // * selectorWithoutVariant + selectorWithVariant
 130                 // * prefix + selector
 131                 // * prefix + selectorWithoutVariant + selectorWithVariant
 132
 133                 $prefix = isset( $options['prefix'] ) && $options['prefix'];
 134                 $selector = isset( $options['selector'] ) && $options['selector'];
 135                 $selectorWithoutVariant = isset( $options['selectorWithoutVariant'] ) && $options['selectorWithoutVariant'];
 136                 $selectorWithVariant = isset( $options['selectorWithVariant'] ) && $options['selectorWithVariant'];
 137
 138                 if ( $selectorWithoutVariant && !$selectorWithVariant ) {
 139                         throw new InvalidArgumentException( "Given 'selectorWithoutVariant' but no 'selectorWithVariant'." );
 140                 }
 141                 if ( $selectorWithVariant && !$selectorWithoutVariant ) {
 142                         throw new InvalidArgumentException( "Given 'selectorWithVariant' but no 'selectorWithoutVariant'." );
 143                 }
 144                 if ( $selector && $selectorWithVariant ) {
 145                         throw new InvalidArgumentException( "Incompatible 'selector' and 'selectorWithVariant'+'selectorWithoutVariant' given." );
 146                 }
 147                 if ( !$prefix && !$selector && !$selectorWithVariant ) {
 148                         throw new InvalidArgumentException( "None of 'prefix', 'selector' or 'selectorWithVariant'+'selectorWithoutVariant' given." );
 149                 }
 150
 151                 foreach ( $options as $member => $option ) {
 152                         switch ( $member ) {
 153                                 case 'images':
 154                                 case 'variants':
 155                                         if ( !is_array( $option ) ) {
 156                                                 throw new InvalidArgumentException(
 157                                                         "Invalid list error. '$option' given, array expected."
 158                                                 );
 159                                         }
 160                                         if ( !isset( $option['default'] ) ) {
 161                                                 // Backwards compatibility
 162                                                 $option = array( 'default' => $option );
 163                                         }
 164                                         foreach ( $option as $skin => $data ) {
 165                                                 if ( !is_array( $option ) ) {
 166                                                         throw new InvalidArgumentException(
 167                                                                 "Invalid list error. '$option' given, array expected."
 168                                                         );
 169                                                 }
 170                                         }
 171                                         $this->{$member} = $option;
 172                                         break;
 173
 174                                 case 'position':
 175                                         $this->isPositionDefined = true;
 176                                 case 'prefix':
 177                                 case 'selectorWithoutVariant':
 178                                 case 'selectorWithVariant':
 179                                         $this->{$member} = (string)$option;
 180                                         break;
 181
 182                                 case 'selector':
 183                                         $this->selectorWithoutVariant = $this->selectorWithVariant = (string)$option;
 184                         }
 185                 }
 186         }
 187
 188         /**
 189          * Get CSS class prefix used by this module.
 190          * @return string
 191          */
 192         public function getPrefix() {
 193                 $this->loadFromDefinition();
 194                 return $this->prefix;
 195         }
 196
 197         /**
 198          * Get CSS selector templates used by this module.
 199          * @return string
 200          */
 201         public function getSelectors() {
 202                 $this->loadFromDefinition();
 203                 return array(
 204                         'selectorWithoutVariant' => $this->selectorWithoutVariant,
 205                         'selectorWithVariant' => $this->selectorWithVariant,
 206                 );
 207         }
 208
 209         /**
 210          * Get a ResourceLoaderImage object for given image.
 211          * @param string $name Image name
 212          * @return ResourceLoaderImage|null
 213          */
 214         public function getImage( $name, ResourceLoaderContext $context ) {
 215                 $this->loadFromDefinition();
 216                 $images = $this->getImages( $context );
 217                 return isset( $images[$name] ) ? $images[$name] : null;
 218         }
 219
 220         /**
 221          * Get ResourceLoaderImage objects for all images.
 222          * @return ResourceLoaderImage[] Array keyed by image name
 223          */
 224         public function getImages( ResourceLoaderContext $context ) {
 225                 $skin = $context->getSkin();
 226                 if ( !isset( $this->imageObjects ) ) {
 227                         $this->loadFromDefinition();
 228                         $this->imageObjects = array();
 229                 }
 230                 if ( !isset( $this->imageObjects[ $skin ] ) ) {
 231                         $this->imageObjects[ $skin ] = array();
 232                         if ( !isset( $this->images[ $skin ] ) ) {
 233                                 $this->images[ $skin ] = isset( $this->images[ 'default' ] ) ?
 234                                         $this->images[ 'default' ] :
 235                                         array();
 236                         }
 237                         foreach ( $this->images[ $skin ] as $name => $options ) {
 238                                 $fileDescriptor = is_string( $options ) ? $options : $options['file'];
 239
 240                                 $allowedVariants = array_merge(
 241                                         is_array( $options ) && isset( $options['variants'] ) ? $options['variants'] : array(),
 242                                         $this->getGlobalVariants( $context )
 243                                 );
 244                                 if ( isset( $this->variants[ $skin ] ) ) {
 245                                         $variantConfig = array_intersect_key(
 246                                                 $this->variants[ $skin ],
 247                                                 array_fill_keys( $allowedVariants, true )
 248                                         );
 249                                 } else {
 250                                         $variantConfig = array();
 251                                 }
 252
 253                                 $image = new ResourceLoaderImage(
 254                                         $name,
 255                                         $this->getName(),
 256                                         $fileDescriptor,
 257                                         $this->localBasePath,
 258                                         $variantConfig
 259                                 );
 260                                 $this->imageObjects[ $skin ][ $image->getName() ] = $image;
 261                         }
 262                 }
 263
 264                 return $this->imageObjects[ $skin ];
 265         }
 266
 267         /**
 268          * Get list of variants in this module that are 'global', i.e., available
 269          * for every image regardless of image options.
 270          * @return string[]
 271          */
 272         public function getGlobalVariants( ResourceLoaderContext $context ) {
 273                 $skin = $context->getSkin();
 274                 if ( !isset( $this->globalVariants ) ) {
 275                         $this->loadFromDefinition();
 276                         $this->globalVariants = array();
 277                 }
 278                 if ( !isset( $this->globalVariants[ $skin ] ) ) {
 279                         $this->globalVariants[ $skin ] = array();
 280                         if ( !isset( $this->variants[ $skin ] ) ) {
 281                                 $this->variants[ $skin ] = isset( $this->variants[ 'default' ] ) ?
 282                                         $this->variants[ 'default' ] :
 283                                         array();
 284                         }
 285                         foreach ( $this->variants[ $skin ] as $name => $config ) {
 286                                 if ( isset( $config['global'] ) && $config['global'] ) {
 287                                         $this->globalVariants[ $skin ][] = $name;
 288                                 }
 289                         }
 290                 }
 291
 292                 return $this->globalVariants[ $skin ];
 293         }
 294
 295         /**
 296          * @param ResourceLoaderContext $context
 297          * @return array
 298          */
 299         public function getStyles( ResourceLoaderContext $context ) {
 300                 $this->loadFromDefinition();
 301
 302                 // Build CSS rules
 303                 $rules = array();
 304                 $script = $context->getResourceLoader()->getLoadScript( $this->getSource() );
 305                 $selectors = $this->getSelectors();
 306
 307                 foreach ( $this->getImages( $context ) as $name => $image ) {
 308                         $declarations = $this->getCssDeclarations(
 309                                 $image->getDataUri( $context, null, 'original' ),
 310                                 $image->getUrl( $context, $script, null, 'rasterized' )
 311                         );
 312                         $declarations = implode( "\n\t", $declarations );
 313                         $selector = strtr(
 314                                 $selectors['selectorWithoutVariant'],
 315                                 array(
 316                                         '{prefix}' => $this->getPrefix(),
 317                                         '{name}' => $name,
 318                                         '{variant}' => '',
 319                                 )
 320                         );
 321                         $rules[] = "$selector {\n\t$declarations\n}";
 322
 323                         foreach ( $image->getVariants() as $variant ) {
 324                                 $declarations = $this->getCssDeclarations(
 325                                         $image->getDataUri( $context, $variant, 'original' ),
 326                                         $image->getUrl( $context, $script, $variant, 'rasterized' )
 327                                 );
 328                                 $declarations = implode( "\n\t", $declarations );
 329                                 $selector = strtr(
 330                                         $selectors['selectorWithVariant'],
 331                                         array(
 332                                                 '{prefix}' => $this->getPrefix(),
 333                                                 '{name}' => $name,
 334                                                 '{variant}' => $variant,
 335                                         )
 336                                 );
 337                                 $rules[] = "$selector {\n\t$declarations\n}";
 338                         }
 339                 }
 340
 341                 $style = implode( "\n", $rules );
 342                 return array( 'all' => $style );
 343         }
 344
 345         /**
 346          * SVG support using a transparent gradient to guarantee cross-browser
 347          * compatibility (browsers able to understand gradient syntax support also SVG).
 348          * http://pauginer.tumblr.com/post/36614680636/invisible-gradient-technique
 349          *
 350          * Keep synchronized with the .background-image-svg LESS mixin in
 351          * /resources/src/mediawiki.less/mediawiki.mixins.less.
 352          *
 353          * @param string $primary Primary URI
 354          * @param string $fallback Fallback URI
 355          * @return string[] CSS declarations to use given URIs as background-image
 356          */
 357         protected function getCssDeclarations( $primary, $fallback ) {
 358                 return array(
 359                         "background-image: url($fallback);",
 360                         "background-image: -webkit-linear-gradient(transparent, transparent), url($primary);",
 361                         "background-image: linear-gradient(transparent, transparent), url($primary);",
 362                         "background-image: -o-linear-gradient(transparent, transparent), url($fallback);",
 363                 );
 364         }
 365
 366         /**
 367          * @return bool
 368          */
 369         public function supportsURLLoading() {
 370                 return false;
 371         }
 372
 373         /**
 374          * Get the definition summary for this module.
 375          *
 376          * @param ResourceLoaderContext $context
 377          * @return array
 378          */
 379         public function getDefinitionSummary( ResourceLoaderContext $context ) {
 380                 $this->loadFromDefinition();
 381                 $summary = parent::getDefinitionSummary( $context );
 382                 foreach ( array(
 383                         'localBasePath',
 384                         'images',
 385                         'variants',
 386                         'prefix',
 387                         'selectorWithoutVariant',
 388                         'selectorWithVariant',
 389                 ) as $member ) {
 390                         $summary[$member] = $this->{$member};
 391                 };
 392                 return $summary;
 393         }
 394
 395         /**
 396          * Get the last modified timestamp of this module.
 397          *
 398          * @param ResourceLoaderContext $context Context in which to calculate
 399          *     the modified time
 400          * @return int UNIX timestamp
 401          */
 402         public function getModifiedTime( ResourceLoaderContext $context ) {
 403                 $this->loadFromDefinition();
 404                 $files = array();
 405                 foreach ( $this->getImages( $context ) as $name => $image ) {
 406                         $files[] = $image->getPath( $context );
 407                 }
 408
 409                 $files = array_values( array_unique( $files ) );
 410                 $filesMtime = max( array_map( array( __CLASS__, 'safeFilemtime' ), $files ) );
 411
 412                 return max(
 413                         $filesMtime,
 414                         $this->getDefinitionMtime( $context )
 415                 );
 416         }
 417
 418         /**
 419          * Extract a local base path from module definition information.
 420          *
 421          * @param array $options Module definition
 422          * @param string $localBasePath Path to use if not provided in module definition. Defaults
 423          *     to $IP
 424          * @return string Local base path
 425          */
 426         public static function extractLocalBasePath( $options, $localBasePath = null ) {
 427                 global $IP;
 428
 429                 if ( $localBasePath === null ) {
 430                         $localBasePath = $IP;
 431                 }
 432
 433                 if ( array_key_exists( 'localBasePath', $options ) ) {
 434                         $localBasePath = (string)$options['localBasePath'];
 435                 }
 436
 437                 return $localBasePath;
 438         }
 439
 440         /**
 441          * @return string
 442          */
 443         public function getPosition() {
 444                 $this->loadFromDefinition();
 445                 return $this->position;
 446         }
 447
 448         public function isPositionDefault() {
 449                 $this->loadFromDefinition();
 450                 return parent::isPositionDefault();
 451         }
 452 }