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