includes/resourceloader/ResourceLoaderImageModule.php

   1 <?php
   2 /**
   3  * ResourceLoader 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  * ResourceLoader 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 = [];
  42         protected $variants = [];
  43         protected $prefix = null;
  44         protected $selectorWithoutVariant = '.{prefix}-{name}';
  45         protected $selectorWithVariant = '.{prefix}-{name}-{variant}';
  46         protected $targets = [ 'desktop', 'mobile' ];
  47
  48         /**
  49          * Constructs a new module from an options array.
  50          *
  51          * @param array $options List of options; if not given or empty, an empty module will be
  52          *     constructed
  53          * @param string $localBasePath Base path to prepend to all local paths in $options. Defaults
  54          *     to $IP
  55          *
  56          * Below is a description for the $options array:
  57          * @par Construction options:
  58          * @code
  59          *     [
  60          *         // Base path to prepend to all local paths in $options. Defaults to $IP
  61          *         'localBasePath' => [base path],
  62          *         // Path to JSON file that contains any of the settings below
  63          *         'data' => [file path string]
  64          *         // CSS class prefix to use in all style rules
  65          *         'prefix' => [CSS class prefix],
  66          *         // Alternatively: Format of CSS selector to use in all style rules
  67          *         'selector' => [CSS selector template, variables: {prefix} {name} {variant}],
  68          *         // Alternatively: When using variants
  69          *         'selectorWithoutVariant' => [CSS selector template, variables: {prefix} {name}],
  70          *         'selectorWithVariant' => [CSS selector template, variables: {prefix} {name} {variant}],
  71          *         // List of variants that may be used for the image files
  72          *         'variants' => [
  73          *             // This level of nesting can be omitted if you use the same images for every skin
  74          *             [skin name (or 'default')] => [
  75          *                 [variant name] => [
  76          *                     'color' => [color string, e.g. '#ffff00'],
  77          *                     'global' => [boolean, if true, this variant is available
  78          *                                  for all images of this type],
  79          *                 ],
  80          *                 ...
  81          *             ],
  82          *             ...
  83          *         ],
  84          *         // List of image files and their options
  85          *         'images' => [
  86          *             // This level of nesting can be omitted if you use the same images for every skin
  87          *             [skin name (or 'default')] => [
  88          *                 [icon name] => [
  89          *                     'file' => [file path string or array whose values are file path strings
  90          *                                    and whose keys are 'default', 'ltr', 'rtl', a single
  91          *                                    language code like 'en', or a list of language codes like
  92          *                                    'en,de,ar'],
  93          *                     'variants' => [array of variant name strings, variants
  94          *                                    available for this image],
  95          *                 ],
  96          *                 ...
  97          *             ],
  98          *             ...
  99          *         ],
 100          *     ]
 101          * @endcode
 102          * @throws InvalidArgumentException
 103          */
 104         public function __construct( $options = [], $localBasePath = null ) {
 105                 $this->localBasePath = self::extractLocalBasePath( $options, $localBasePath );
 106
 107                 $this->definition = $options;
 108         }
 109
 110         /**
 111          * Parse definition and external JSON data, if referenced.
 112          */
 113         protected function loadFromDefinition() {
 114                 if ( $this->definition === null ) {
 115                         return;
 116                 }
 117
 118                 $options = $this->definition;
 119                 $this->definition = null;
 120
 121                 if ( isset( $options['data'] ) ) {
 122                         $dataPath = $this->localBasePath . '/' . $options['data'];
 123                         $data = json_decode( file_get_contents( $dataPath ), true );
 124                         $options = array_merge( $data, $options );
 125                 }
 126
 127                 // Accepted combinations:
 128                 // * prefix
 129                 // * selector
 130                 // * selectorWithoutVariant + selectorWithVariant
 131                 // * prefix + selector
 132                 // * prefix + selectorWithoutVariant + selectorWithVariant
 133
 134                 $prefix = isset( $options['prefix'] ) && $options['prefix'];
 135                 $selector = isset( $options['selector'] ) && $options['selector'];
 136                 $selectorWithoutVariant = isset( $options['selectorWithoutVariant'] )
 137                         && $options['selectorWithoutVariant'];
 138                 $selectorWithVariant = isset( $options['selectorWithVariant'] )
 139                         && $options['selectorWithVariant'];
 140
 141                 if ( $selectorWithoutVariant && !$selectorWithVariant ) {
 142                         throw new InvalidArgumentException(
 143                                 "Given 'selectorWithoutVariant' but no 'selectorWithVariant'."
 144                         );
 145                 }
 146                 if ( $selectorWithVariant && !$selectorWithoutVariant ) {
 147                         throw new InvalidArgumentException(
 148                                 "Given 'selectorWithVariant' but no 'selectorWithoutVariant'."
 149                         );
 150                 }
 151                 if ( $selector && $selectorWithVariant ) {
 152                         throw new InvalidArgumentException(
 153                                 "Incompatible 'selector' and 'selectorWithVariant'+'selectorWithoutVariant' given."
 154                         );
 155                 }
 156                 if ( !$prefix && !$selector && !$selectorWithVariant ) {
 157                         throw new InvalidArgumentException(
 158                                 "None of 'prefix', 'selector' or 'selectorWithVariant'+'selectorWithoutVariant' given."
 159                         );
 160                 }
 161
 162                 foreach ( $options as $member => $option ) {
 163                         switch ( $member ) {
 164                                 case 'images':
 165                                 case 'variants':
 166                                         if ( !is_array( $option ) ) {
 167                                                 throw new InvalidArgumentException(
 168                                                         "Invalid list error. '$option' given, array expected."
 169                                                 );
 170                                         }
 171                                         if ( !isset( $option['default'] ) ) {
 172                                                 // Backwards compatibility
 173                                                 $option = [ 'default' => $option ];
 174                                         }
 175                                         foreach ( $option as $skin => $data ) {
 176                                                 if ( !is_array( $option ) ) {
 177                                                         throw new InvalidArgumentException(
 178                                                                 "Invalid list error. '$option' given, array expected."
 179                                                         );
 180                                                 }
 181                                         }
 182                                         $this->{$member} = $option;
 183                                         break;
 184
 185                                 case 'prefix':
 186                                 case 'selectorWithoutVariant':
 187                                 case 'selectorWithVariant':
 188                                         $this->{$member} = (string)$option;
 189                                         break;
 190
 191                                 case 'selector':
 192                                         $this->selectorWithoutVariant = $this->selectorWithVariant = (string)$option;
 193                         }
 194                 }
 195         }
 196
 197         /**
 198          * Get CSS class prefix used by this module.
 199          * @return string
 200          */
 201         public function getPrefix() {
 202                 $this->loadFromDefinition();
 203                 return $this->prefix;
 204         }
 205
 206         /**
 207          * Get CSS selector templates used by this module.
 208          * @return string
 209          */
 210         public function getSelectors() {
 211                 $this->loadFromDefinition();
 212                 return [
 213                         'selectorWithoutVariant' => $this->selectorWithoutVariant,
 214                         'selectorWithVariant' => $this->selectorWithVariant,
 215                 ];
 216         }
 217
 218         /**
 219          * Get a ResourceLoaderImage object for given image.
 220          * @param string $name Image name
 221          * @param ResourceLoaderContext $context
 222          * @return ResourceLoaderImage|null
 223          */
 224         public function getImage( $name, ResourceLoaderContext $context ) {
 225                 $this->loadFromDefinition();
 226                 $images = $this->getImages( $context );
 227                 return isset( $images[$name] ) ? $images[$name] : null;
 228         }
 229
 230         /**
 231          * Get ResourceLoaderImage objects for all images.
 232          * @param ResourceLoaderContext $context
 233          * @return ResourceLoaderImage[] Array keyed by image name
 234          */
 235         public function getImages( ResourceLoaderContext $context ) {
 236                 $skin = $context->getSkin();
 237                 if ( !isset( $this->imageObjects ) ) {
 238                         $this->loadFromDefinition();
 239                         $this->imageObjects = [];
 240                 }
 241                 if ( !isset( $this->imageObjects[$skin] ) ) {
 242                         $this->imageObjects[$skin] = [];
 243                         if ( !isset( $this->images[$skin] ) ) {
 244                                 $this->images[$skin] = isset( $this->images['default'] ) ?
 245                                         $this->images['default'] :
 246                                         [];
 247                         }
 248                         foreach ( $this->images[$skin] as $name => $options ) {
 249                                 $fileDescriptor = is_string( $options ) ? $options : $options['file'];
 250
 251                                 $allowedVariants = array_merge(
 252                                         ( is_array( $options ) && isset( $options['variants'] ) ) ? $options['variants'] : [],
 253                                         $this->getGlobalVariants( $context )
 254                                 );
 255                                 if ( isset( $this->variants[$skin] ) ) {
 256                                         $variantConfig = array_intersect_key(
 257                                                 $this->variants[$skin],
 258                                                 array_fill_keys( $allowedVariants, true )
 259                                         );
 260                                 } else {
 261                                         $variantConfig = [];
 262                                 }
 263
 264                                 $image = new ResourceLoaderImage(
 265                                         $name,
 266                                         $this->getName(),
 267                                         $fileDescriptor,
 268                                         $this->localBasePath,
 269                                         $variantConfig
 270                                 );
 271                                 $this->imageObjects[$skin][$image->getName()] = $image;
 272                         }
 273                 }
 274
 275                 return $this->imageObjects[$skin];
 276         }
 277
 278         /**
 279          * Get list of variants in this module that are 'global', i.e., available
 280          * for every image regardless of image options.
 281          * @param ResourceLoaderContext $context
 282          * @return string[]
 283          */
 284         public function getGlobalVariants( ResourceLoaderContext $context ) {
 285                 $skin = $context->getSkin();
 286                 if ( !isset( $this->globalVariants ) ) {
 287                         $this->loadFromDefinition();
 288                         $this->globalVariants = [];
 289                 }
 290                 if ( !isset( $this->globalVariants[$skin] ) ) {
 291                         $this->globalVariants[$skin] = [];
 292                         if ( !isset( $this->variants[$skin] ) ) {
 293                                 $this->variants[$skin] = isset( $this->variants['default'] ) ?
 294                                         $this->variants['default'] :
 295                                         [];
 296                         }
 297                         foreach ( $this->variants[$skin] as $name => $config ) {
 298                                 if ( isset( $config['global'] ) && $config['global'] ) {
 299                                         $this->globalVariants[$skin][] = $name;
 300                                 }
 301                         }
 302                 }
 303
 304                 return $this->globalVariants[$skin];
 305         }
 306
 307         /**
 308          * @param ResourceLoaderContext $context
 309          * @return array
 310          */
 311         public function getStyles( ResourceLoaderContext $context ) {
 312                 $this->loadFromDefinition();
 313
 314                 // Build CSS rules
 315                 $rules = [];
 316                 $script = $context->getResourceLoader()->getLoadScript( $this->getSource() );
 317                 $selectors = $this->getSelectors();
 318
 319                 foreach ( $this->getImages( $context ) as $name => $image ) {
 320                         $declarations = $this->getStyleDeclarations( $context, $image, $script );
 321                         $selector = strtr(
 322                                 $selectors['selectorWithoutVariant'],
 323                                 [
 324                                         '{prefix}' => $this->getPrefix(),
 325                                         '{name}' => $name,
 326                                         '{variant}' => '',
 327                                 ]
 328                         );
 329                         $rules[] = "$selector {\n\t$declarations\n}";
 330
 331                         foreach ( $image->getVariants() as $variant ) {
 332                                 $declarations = $this->getStyleDeclarations( $context, $image, $script, $variant );
 333                                 $selector = strtr(
 334                                         $selectors['selectorWithVariant'],
 335                                         [
 336                                                 '{prefix}' => $this->getPrefix(),
 337                                                 '{name}' => $name,
 338                                                 '{variant}' => $variant,
 339                                         ]
 340                                 );
 341                                 $rules[] = "$selector {\n\t$declarations\n}";
 342                         }
 343                 }
 344
 345                 $style = implode( "\n", $rules );
 346                 return [ 'all' => $style ];
 347         }
 348
 349         /**
 350          * @param ResourceLoaderContext $context
 351          * @param ResourceLoaderImage $image Image to get the style for
 352          * @param string $script URL to load.php
 353          * @param string|null $variant Variant to get the style for
 354          * @return string
 355          */
 356         private function getStyleDeclarations(
 357                 ResourceLoaderContext $context,
 358                 ResourceLoaderImage $image,
 359                 $script,
 360                 $variant = null
 361         ) {
 362                 $imageDataUri = $image->getDataUri( $context, $variant, 'original' );
 363                 $primaryUrl = $imageDataUri ?: $image->getUrl( $context, $script, $variant, 'original' );
 364                 $declarations = $this->getCssDeclarations(
 365                         $primaryUrl,
 366                         $image->getUrl( $context, $script, $variant, 'rasterized' )
 367                 );
 368                 return implode( "\n\t", $declarations );
 369         }
 370
 371         /**
 372          * SVG support using a transparent gradient to guarantee cross-browser
 373          * compatibility (browsers able to understand gradient syntax support also SVG).
 374          * http://pauginer.tumblr.com/post/36614680636/invisible-gradient-technique
 375          *
 376          * Keep synchronized with the .background-image-svg LESS mixin in
 377          * /resources/src/mediawiki.less/mediawiki.mixins.less.
 378          *
 379          * @param string $primary Primary URI
 380          * @param string $fallback Fallback URI
 381          * @return string[] CSS declarations to use given URIs as background-image
 382          */
 383         protected function getCssDeclarations( $primary, $fallback ) {
 384                 $primaryUrl = CSSMin::buildUrlValue( $primary );
 385                 $fallbackUrl = CSSMin::buildUrlValue( $fallback );
 386                 return [
 387                         "background-image: $fallbackUrl;",
 388                         "background-image: linear-gradient(transparent, transparent), $primaryUrl;",
 389                 ];
 390         }
 391
 392         /**
 393          * @return bool
 394          */
 395         public function supportsURLLoading() {
 396                 return false;
 397         }
 398
 399         /**
 400          * Get the definition summary for this module.
 401          *
 402          * @param ResourceLoaderContext $context
 403          * @return array
 404          */
 405         public function getDefinitionSummary( ResourceLoaderContext $context ) {
 406                 $this->loadFromDefinition();
 407                 $summary = parent::getDefinitionSummary( $context );
 408
 409                 $options = [];
 410                 foreach ( [
 411                         'localBasePath',
 412                         'images',
 413                         'variants',
 414                         'prefix',
 415                         'selectorWithoutVariant',
 416                         'selectorWithVariant',
 417                 ] as $member ) {
 418                         $options[$member] = $this->{$member};
 419                 };
 420
 421                 $summary[] = [
 422                         'options' => $options,
 423                         'fileHashes' => $this->getFileHashes( $context ),
 424                 ];
 425                 return $summary;
 426         }
 427
 428         /**
 429          * Helper method for getDefinitionSummary.
 430          * @param ResourceLoaderContext $context
 431          * @return array
 432          */
 433         protected function getFileHashes( ResourceLoaderContext $context ) {
 434                 $this->loadFromDefinition();
 435                 $files = [];
 436                 foreach ( $this->getImages( $context ) as $name => $image ) {
 437                         $files[] = $image->getPath( $context );
 438                 }
 439                 $files = array_values( array_unique( $files ) );
 440                 return array_map( [ __CLASS__, 'safeFileHash' ], $files );
 441         }
 442
 443         /**
 444          * Extract a local base path from module definition information.
 445          *
 446          * @param array $options Module definition
 447          * @param string $localBasePath Path to use if not provided in module definition. Defaults
 448          *     to $IP
 449          * @return string Local base path
 450          */
 451         public static function extractLocalBasePath( $options, $localBasePath = null ) {
 452                 global $IP;
 453
 454                 if ( $localBasePath === null ) {
 455                         $localBasePath = $IP;
 456                 }
 457
 458                 if ( array_key_exists( 'localBasePath', $options ) ) {
 459                         $localBasePath = (string)$options['localBasePath'];
 460                 }
 461
 462                 return $localBasePath;
 463         }
 464
 465         /**
 466          * @return string
 467          */
 468         public function getType() {
 469                 return self::LOAD_STYLES;
 470         }
 471 }