/* * This file is part of the MediaWiki extension MultimediaViewer. * * MultimediaViewer is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 2 of the License, or * (at your option) any later version. * * MultimediaViewer is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with MultimediaViewer. If not, see . */ const { getMediaHash } = require( 'mmv.head' ); const ViewLogger = require( './logging/mmv.logging.ViewLogger.js' ); const Api = require( './provider/mmv.provider.Api.js' ); const FileRepoInfo = require( './provider/mmv.provider.FileRepoInfo.js' ); const GuessedThumbnailInfo = require( './provider/mmv.provider.GuessedThumbnailInfo.js' ); const ImageProvider = require( './provider/mmv.provider.Image.js' ); const ImageInfo = require( './provider/mmv.provider.ImageInfo.js' ); const ThumbnailInfo = require( './provider/mmv.provider.ThumbnailInfo.js' ); const ImageModel = require( './model/mmv.model.Image.js' ); const IwTitle = require( './model/mmv.model.IwTitle.js' ); const License = require( './model/mmv.model.License.js' ); const { Repo, ForeignApiRepo, ForeignDbRepo } = require( './model/mmv.model.Repo.js' ); const TaskQueue = require( './model/mmv.model.TaskQueue.js' ); const Thumbnail = require( './model/mmv.model.Thumbnail.js' ); const ThumbnailWidth = require( './model/mmv.model.ThumbnailWidth.js' ); const Canvas = require( './ui/mmv.ui.canvas.js' ); const CanvasButtons = require( './ui/mmv.ui.canvasButtons.js' ); const Description = require( './ui/mmv.ui.description.js' ); const Dialog = require( './ui/mmv.ui.dialog.js' ); const UiElement = require( './ui/mmv.ui.js' ); const MetadataPanel = require( './ui/mmv.ui.metadataPanel.js' ); const MetadataPanelScroller = require( './ui/mmv.ui.metadataPanelScroller.js' ); const Permission = require( './ui/mmv.ui.permission.js' ); const ProgressBar = require( './ui/mmv.ui.progressBar.js' ); const StripeButtons = require( './ui/mmv.ui.stripeButtons.js' ); const TruncatableTextField = require( './ui/mmv.ui.truncatableTextField.js' ); const OptionsDialog = require( './ui/mmv.ui.viewingOptions.js' ); const LightboxInterface = require( './mmv.lightboxinterface.js' ); const ThumbnailWidthCalculator = require( './mmv.ThumbnailWidthCalculator.js' ); const router = require( 'mediawiki.router' ); let comingFromHashChange = false; /** * Analyses the page, looks for image content and sets up the hooks * to manage the viewing experience of such content. */ class MultimediaViewer { /** * @param {Config} config Config object */ constructor( config ) { const apiCacheMaxAge = 86400; // one day (24 hours * 60 min * 60 sec) const apiCacheFiveMinutes = 300; // 5 min * 60 sec const api = new mw.Api(); /** * @property {Config} * @private */ this.config = config; /** * @property {ImageProvider} * @private */ this.imageProvider = new ImageProvider( this.config.imageQueryParameter() ); /** * @property {ImageInfo} * @private */ this.imageInfoProvider = new ImageInfo( api, { language: this.config.language(), maxage: apiCacheFiveMinutes } ); /** * @property {FileRepoInfo} * @private */ this.fileRepoInfoProvider = new FileRepoInfo( api, { maxage: apiCacheMaxAge } ); /** * @property {ThumbnailInfo} * @private */ this.thumbnailInfoProvider = new ThumbnailInfo( api, { maxage: apiCacheMaxAge } ); /** * @property {ThumbnailInfo} * @private */ this.guessedThumbnailInfoProvider = new GuessedThumbnailInfo(); /** * Image index on page. * * @property {number} */ this.currentIndex = 0; /** * @property {OO.Router} router */ this.router = router; this.setupRouter(); comingFromHashChange = false; /** * UI object used to display the pictures in the page. * * @property {LightboxInterface} * @private */ this.ui = new LightboxInterface(); /** * How many sharp images have been displayed in Media Viewer since the pageload * * @property {number} */ this.imageDisplayedCount = 0; /** * How many data-filled metadata panels have been displayed in Media Viewer since the pageload * * @property {number} */ this.metadataDisplayedCount = 0; /** @property {string} documentTitle base document title, MediaViewer will expand this */ this.documentTitle = document.title; /** * @property {ViewLogger} view - */ this.viewLogger = new ViewLogger( this.config, window ); /** * Stores whether the real image was loaded and displayed already. * This is reset when paging, so it is not necessarily accurate. * * @property {boolean} */ this.realThumbnailShown = false; } /** * Initialize the lightbox interface given an array of thumbnail * objects. * * @param {LightboxImage[]} thumbs */ initWithThumbs( thumbs ) { this.thumbs = thumbs; } /** * Handles resize events in viewer. * * @protected * @param {LightboxInterface} ui lightbox that got resized */ resize( ui ) { const image = this.thumbs[ this.currentIndex ]; const ext = this.thumbs[ this.currentIndex ].filePageTitle.getExtension().toLowerCase(); this.preloadThumbnails(); if ( image ) { const imageWidths = ui.canvas.getCurrentImageWidths(); this.fetchThumbnailForLightboxImage( image, imageWidths.real ).then( ( thumbnail, image2 ) => { // eslint-disable-next-line mediawiki/class-doc image2.className = ext; this.setImage( ui, thumbnail, image2, imageWidths ); }, ( error ) => { this.ui.canvas.showError( error ); } ); } this.updateControls(); } /** * Updates positioning of controls, usually after a resize event. */ updateControls() { const numImages = this.thumbs ? this.thumbs.length : 0; const showNextButton = this.currentIndex < ( numImages - 1 ); const showPreviousButton = this.currentIndex > 0; this.ui.updateControls( showNextButton, showPreviousButton ); } /** * Loads and sets the specified image. It also updates the controls. * * @param {LightboxInterface} ui image container * @param {Thumbnail} thumbnail thumbnail information * @param {HTMLImageElement} imageElement * @param {ThumbnailWidth} imageWidths */ setImage( ui, thumbnail, imageElement, imageWidths ) { ui.canvas.setImageAndMaxDimensions( thumbnail, imageElement, imageWidths ); this.updateControls(); } /** * Loads a specified image. * * @param {LightboxImage} image */ loadImage( image ) { const $initialImage = $( image.thumbnail ).clone(); const pluginsPromise = this.loadExtensionPlugins( image.filePageTitle.getExtension().toLowerCase() ); this.currentIndex = image.index; this.currentImageFileTitle = image.filePageTitle; if ( !this.isOpen ) { $( document ).trigger( $.Event( 'mmv-setup-overlay' ) ); this.ui.open(); this.isOpen = true; } else { this.ui.empty(); } this.setTitle(); // At this point we can't show the thumbnail because we don't // know what size it should be. We still assign it to allow for // size calculations in getCurrentImageWidths, which needs to know // the aspect ratio // eslint-disable-next-line mediawiki/class-doc $initialImage.hide() .removeAttr( 'style' ) .removeClass() .addClass( `mw-mmv-placeholder-image ${ image.filePageTitle.getExtension().toLowerCase() }` ); this.ui.canvas.set( image, $initialImage ); this.preloadImagesMetadata(); this.preloadThumbnails(); // this.preloadFullscreenThumbnail( image ); // disabled - #474 const imageWidths = this.ui.canvas.getCurrentImageWidths(); const start = Date.now(); const imagePromise = this.fetchThumbnailForLightboxImage( image, imageWidths.real ); if ( imagePromise.state() === 'pending' ) { this.displayPlaceholderThumbnail( image, $initialImage, imageWidths ); } this.resetThumbnailStates(); this.setupProgressBar( image, imagePromise, imageWidths.real ); const metadataPromise = this.fetchSizeIndependentLightboxInfo( image.filePageTitle ); imagePromise.then( // done ( thumbnail, imageElement ) => { if ( this.currentIndex !== image.index ) { return; } // eslint-disable-next-line mediawiki/class-doc imageElement.className = `mw-mmv-final-image ${ image.filePageTitle.getExtension().toLowerCase() }`; imageElement.alt = image.alt; $.when( metadataPromise, pluginsPromise ).then( ( metadata ) => { $( document ).trigger( $.Event( 'mmv-metadata', { viewer: this, image: image, imageInfo: metadata[ 0 ] } ) ); } ); this.displayRealThumbnail( thumbnail, imageElement, imageWidths, Date.now() - start ); return $.Deferred().resolve( thumbnail, imageElement ); }, // fail ( error ) => { this.ui.canvas.showError( error ); return $.Deferred().reject( error ); } ); metadataPromise.then( // done ( imageInfo, repoInfo ) => { if ( this.currentIndex !== image.index ) { return; } this.ui.panel.setImageInfo( image, imageInfo, repoInfo ); // File reuse steals a bunch of information from the DOM, so do it last this.ui.setFileReuseData( imageInfo, repoInfo, image.caption, image.alt ); return $.Deferred().resolve( imageInfo, repoInfo ); }, // fail ( error ) => { if ( this.currentIndex === image.index ) { // Set title to caption or file name if caption is not available; // see setTitle() in mmv.ui.metadataPanel for extended caption fallback this.ui.panel.showError( image.caption || image.filePageTitle.getNameText(), error ); } return $.Deferred().reject( error ); } ); $.when( imagePromise, metadataPromise ).then( () => { if ( this.currentIndex !== image.index ) { return; } this.ui.panel.scroller.animateMetadataOnce(); } ); } /** * Loads an image by its title * * @param {mw.Title} title * @param {number} [position] */ loadImageByTitle( title, position ) { if ( !this.thumbs || !this.thumbs.length ) { return; } const thumb = this.thumbs.find( ( t ) => t.filePageTitle.getPrefixedText() === title.getPrefixedText() && ( !position || t.position === position ) ); if ( !thumb ) { this.onTitleNotFound( title ); return; } this.loadImage( thumb ); } /** * When the image to load is not present on the current page, * a notification is shown to the user and the MMV is closed. * * @param {mw.Title} title * @private */ onTitleNotFound( title ) { this.close(); const text = mw.msg( 'multimediaviewer-file-not-found-error', title.getMainText() ); const $link = $( '' ).text( mw.msg( 'multimediaviewer-file-page' ) ).prop( 'href', title.getUrl() ); const $message = $( '
' ).text( text ).append( $( '
' ) ).append( $link ); mw.notify( $message ); } /** * Resets the cross-request states needed to handle the thumbnail logic. */ resetThumbnailStates() { this.realThumbnailShown = false; } /** * Display the real, full-resolution, thumbnail that was fetched with fetchThumbnail * * @param {Thumbnail} thumbnail * @param {HTMLImageElement} imageElement * @param {ThumbnailWidth} imageWidths */ displayRealThumbnail( thumbnail, imageElement, imageWidths ) { this.realThumbnailShown = true; this.setImage( this.ui, thumbnail, imageElement, imageWidths ); this.viewLogger.attach( thumbnail.url ); } /** * Display the thumbnail from the page * * @param {LightboxImage} image * @param {jQuery} $initialImage The thumbnail from the page * @param {ThumbnailWidth} imageWidths * @param {boolean} [recursion=false] for internal use, never set this when calling from outside */ displayPlaceholderThumbnail( image, $initialImage, imageWidths, recursion ) { const size = { width: image.originalWidth, height: image.originalHeight }; // If the actual image has already been displayed, there's no point showing the thumbnail. // This can happen if the API request to get the original image size needed to show the // placeholder thumbnail takes longer then loading the actual thumbnail. if ( this.realThumbnailShown ) { return; } // Width/height of the original image are added to the HTML by MediaViewer via a PHP hook, // and can be missing in exotic circumstances, e. g. when the extension has only been // enabled recently and the HTML cache has not cleared yet. If that is the case, we need // to fetch the size from the API first. if ( !size.width || !size.height ) { if ( recursion ) { // this should not be possible, but an infinite recursion is nasty // business, so we make a sense check throw new Error( 'MediaViewer internal error: displayPlaceholderThumbnail recursion' ); } this.imageInfoProvider.get( image.filePageTitle ).done( ( imageInfo ) => { // Make sure the user has not navigated away while we were waiting for the size if ( this.currentIndex === image.index ) { image.originalWidth = imageInfo.width; image.originalHeight = imageInfo.height; this.displayPlaceholderThumbnail( image, $initialImage, imageWidths, true ); } } ); } else { this.ui.canvas.maybeDisplayPlaceholder( size, $initialImage, imageWidths ); } } /** * Displays a progress bar for the image loading, if necessary, and sets up handling of * all the related callbacks. * * @param {LightboxImage} image * @param {jQuery.Promise.} imagePromise * @param {number} imageWidth needed for caching progress (FIXME) */ setupProgressBar( image, imagePromise, imageWidth ) { const progressBar = this.ui.panel.progressBar; const key = `${ image.filePageTitle.getPrefixedDb() }|${ imageWidth }`; if ( !this.progressCache[ key ] ) { // Animate progress bar to 5 to give a sense that something is happening, and make sure // the progress bar is noticeable, even if we're sitting at 0% stuck waiting for // server-side processing, such as thumbnail (re)generation progressBar.jumpTo( 0 ); progressBar.animateTo( 5 ); this.progressCache[ key ] = 5; } else { progressBar.jumpTo( this.progressCache[ key ] ); } // FIXME would be nice to have a "filtered" promise which does not fire when the image is not visible imagePromise.then( // done ( thumbnail, imageElement ) => { this.progressCache[ key ] = 100; if ( this.currentIndex === image.index ) { // Fallback in case the browser doesn't have fancy progress updates progressBar.animateTo( 100 ); // Hide progress bar, we're done // TODO not really needed, but testcase depends on it progressBar.hide(); } return $.Deferred().resolve( thumbnail, imageElement ); }, // fail ( error ) => { this.progressCache[ key ] = 100; if ( this.currentIndex === image.index ) { // Hide progress bar on error progressBar.hide(); } return $.Deferred().reject( error ); }, // progress ( progress ) => { // We pretend progress is always at least 5%, so progress events below 5% should be ignored // 100 will be handled by the done handler, do not mix two animations if ( progress >= 5 && progress < 100 ) { this.progressCache[ key ] = progress; // Touch the UI only if the user is looking at this image if ( this.currentIndex === image.index ) { progressBar.animateTo( progress ); } } return progress; } ); } /** * Orders lightboximage indexes for preloading. Works similar to $.each, except it only takes * the callback argument. Calls the callback with each lightboximage index in some sequence * that is ideal for preloading. * * @private * @param {function(number, LightboxImage)} callback */ eachPreloadableLightboxIndex( callback ) { for ( let i = 0; i <= this.preloadDistance; i++ ) { if ( this.currentIndex + i < this.thumbs.length ) { callback( this.currentIndex + i, this.thumbs[ this.currentIndex + i ] ); } if ( i && this.currentIndex - i >= 0 ) { // skip duplicate for i==0 callback( this.currentIndex - i, this.thumbs[ this.currentIndex - i ] ); } } } /** * A helper function to fill up the preload queues. * taskFactory(lightboxImage) should return a preload task for the given lightboximage. * * @private * @param {function(LightboxImage)} taskFactory * @return {TaskQueue} */ pushLightboxImagesIntoQueue( taskFactory ) { const queue = new TaskQueue(); this.eachPreloadableLightboxIndex( ( i, lightboxImage ) => { queue.push( taskFactory( lightboxImage ) ); } ); return queue; } /** * Cancels in-progress image metadata preloading. */ cancelImageMetadataPreloading() { if ( this.metadataPreloadQueue ) { this.metadataPreloadQueue.cancel(); } } /** * Cancels in-progress image thumbnail preloading. */ cancelThumbnailsPreloading() { if ( this.thumbnailPreloadQueue ) { this.thumbnailPreloadQueue.cancel(); } } /** * Preload metadata for next and prev N image (N = MMVP.preloadDistance). * Two images will be loaded at a time (one forward, one backward), with closer images * being loaded sooner. */ preloadImagesMetadata() { this.cancelImageMetadataPreloading(); this.metadataPreloadQueue = this.pushLightboxImagesIntoQueue( ( lightboxImage ) => { return () => this.fetchSizeIndependentLightboxInfo( lightboxImage.filePageTitle ); } ); this.metadataPreloadQueue.execute(); } /** * Preload thumbnails for next and prev N image (N = MMVP.preloadDistance). * Two images will be loaded at a time (one forward, one backward), with closer images * being loaded sooner. */ preloadThumbnails() { this.cancelThumbnailsPreloading(); this.thumbnailPreloadQueue = this.pushLightboxImagesIntoQueue( ( lightboxImage ) => { return () => { // viewer.ui.canvas.getLightboxImageWidths needs the viewer to be open // because it needs to read the size of visible elements if ( !this.isOpen ) { return; } const imageWidths = this.ui.canvas.getLightboxImageWidths( lightboxImage ); return this.fetchThumbnailForLightboxImage( lightboxImage, imageWidths.real ); }; } ); this.thumbnailPreloadQueue.execute(); } /** * Preload the fullscreen size of the current image. * * @param {LightboxImage} image */ preloadFullscreenThumbnail( image ) { const imageWidths = this.ui.canvas.getLightboxImageWidthsForFullscreen( image ); this.fetchThumbnailForLightboxImage( image, imageWidths.real ); } /** * Loads all the size-independent information needed by the lightbox (image metadata, repo * information). * * @param {mw.Title} fileTitle Title of the file page for the image. * @return {jQuery.Promise.} */ fetchSizeIndependentLightboxInfo( fileTitle ) { const imageInfoPromise = this.imageInfoProvider.get( fileTitle ); const repoInfoPromise = this.fileRepoInfoProvider.get( fileTitle ); return $.when( imageInfoPromise, repoInfoPromise ).then( ( imageInfo, repoInfoHash ) => { return $.Deferred().resolve( imageInfo, repoInfoHash[ imageInfo.repo ] ); } ); } /** * Loads size-dependent components of a lightbox - the thumbnail model and the image itself. * * @param {LightboxImage} image * @param {number} width the width of the requested thumbnail * @return {jQuery.Promise.} */ fetchThumbnailForLightboxImage( image, width ) { return this.fetchThumbnail( image.filePageTitle, width, image.src, image.originalWidth, image.originalHeight ); } /** * Loads size-dependent components of a lightbox - the thumbnail model and the image itself. * * @param {mw.Title} fileTitle * @param {number} width the width of the requested thumbnail * @param {string} [sampleUrl] a thumbnail URL for the same file (but with different size) (might be missing) * @param {number} [originalWidth] the width of the original, full-sized file (might be missing) * @param {number} [originalHeight] the height of the original, full-sized file (might be missing) * @return {jQuery.Promise.} A promise resolving to * a thumbnail model and an element. It might or might not have progress events which * return a single number. */ fetchThumbnail( fileTitle, width, sampleUrl, originalWidth, originalHeight ) { let guessing = false; const combinedDeferred = $.Deferred(); let thumbnailPromise; let imagePromise; if ( fileTitle.getExtension().toLowerCase() !== 'svg' && originalWidth && width > originalWidth ) { // Do not request images larger than the original image width = originalWidth; } if ( sampleUrl && originalWidth && originalHeight && this.config.useThumbnailGuessing() ) { guessing = true; thumbnailPromise = this.guessedThumbnailInfoProvider.get( fileTitle, sampleUrl, width, originalWidth, originalHeight ).then( null, () => this.thumbnailInfoProvider.get( fileTitle, width ) ); } else { thumbnailPromise = this.thumbnailInfoProvider.get( fileTitle, width ); } imagePromise = thumbnailPromise.then( ( thumbnail ) => this.imageProvider.get( thumbnail.url ) ); if ( guessing ) { // If we guessed wrong, need to retry with real URL on failure. // As a side effect this introduces an extra (harmless) retry of a failed thumbnailInfoProvider.get call // because thumbnailInfoProvider.get is already called above when guessedThumbnailInfoProvider.get fails. imagePromise = imagePromise .then( null, () => this.thumbnailInfoProvider.get( fileTitle, width ) .then( ( thumbnail ) => this.imageProvider.get( thumbnail.url ) ) ); } // In jQuery<3, $.when used to also relay notify, but that is no longer // the case - but we still want to pass it along... $.when( thumbnailPromise, imagePromise ).then( combinedDeferred.resolve, combinedDeferred.reject ); imagePromise.then( null, null, ( arg, progress ) => { combinedDeferred.notify( progress ); } ); return combinedDeferred; } /** * Loads an image at a specified index in the viewer's thumbnail array. * * @param {number} index */ loadIndex( index ) { if ( index < this.thumbs.length && index >= 0 ) { this.viewLogger.recordViewDuration(); const thumb = this.thumbs[ index ]; this.loadImage( thumb ); router.navigateTo( null, { path: getMediaHash( thumb.filePageTitle, thumb.position ), useReplaceState: true } ); } } /** * Opens the last image */ firstImage() { this.loadIndex( 0 ); } /** * Opens the last image */ lastImage() { this.loadIndex( this.thumbs.length - 1 ); } /** * Opens the next image */ nextImage() { this.loadIndex( this.currentIndex + 1 ); } /** * Opens the previous image */ prevImage() { this.loadIndex( this.currentIndex - 1 ); } /** * Handles close event coming from the lightbox */ close() { this.viewLogger.recordViewDuration(); this.viewLogger.unattach(); if ( comingFromHashChange ) { comingFromHashChange = false; } else { this.router.back(); } // update title after route change, see T225387 document.title = this.createDocumentTitle( null ); // This has to happen after the hash reset, because setting the hash to # will reset the page scroll $( document ).trigger( $.Event( 'mmv-cleanup-overlay' ) ); this.isOpen = false; } /** * Sets up the route handlers */ setupRouter() { // handle empty hashes, and anchor links (page sections) this.router.addRoute( /^[^/]*$/, () => { if ( this.isOpen ) { comingFromHashChange = true; document.title = this.createDocumentTitle( null ); if ( this.ui ) { // FIXME triggers mmv-close event, which calls viewer.close() this.ui.unattach(); } else { this.close(); } } } ); } /** * Updates the page title to reflect the current title. */ setTitle() { // update title after route change, see T225387 document.title = this.createDocumentTitle( this.currentImageFileTitle ); } /** * Creates a string which can be shown as document title (the text at the top of the browser window). * * @param {mw.Title|null} imageTitle the title object for the image which is displayed; null when the * viewer is being closed * @return {string} */ createDocumentTitle( imageTitle ) { if ( imageTitle ) { return `${ imageTitle.getNameText() } - ${ this.documentTitle }`; } else { return this.documentTitle; } } /** * Fired when the viewer is closed. This is used by the lightbox to notify the main app. * * @event MultimediaViewer#mmv-close */ /** * Fired when the user requests the next image. * * @event MultimediaViewer#mmv-next */ /** * Fired when the user requests the previous image. * * @event MultimediaViewer#mmv-prev */ /** * Fired when the screen size changes. Debounced to avoid continuous triggering while resizing with a mouse. * * @event MultimediaViewer#mmv-resize-end */ /** * Used by components to request a thumbnail URL for the current thumbnail, with a given size. * * @event MultimediaViewer#mmv-request-thumbnail * @param {number} size */ /** * Registers all event handlers */ setupEventHandlers() { this.ui.connect( this, { first: 'firstImage', last: 'lastImage', next: 'nextImage', prev: 'prevImage' } ); $( document ).on( 'mmv-close.mmvp', () => { this.close(); } ).on( 'mmv-resize-end.mmvp', () => { this.resize( this.ui ); } ).on( 'mmv-request-thumbnail.mmvp', ( e, size ) => { if ( this.currentImageFileTitle ) { return this.thumbnailInfoProvider.get( this.currentImageFileTitle, size ); } else { return $.Deferred().reject(); } } ).on( 'mmv-viewfile.mmvp', () => { this.imageInfoProvider.get( this.currentImageFileTitle ).done( ( imageInfo ) => { document.location = imageInfo.url; } ); } ); } /** * Unregisters all event handlers. Currently only used in tests. */ cleanupEventHandlers() { $( document ).off( 'mmv-close.mmvp mmv-resize-end.mmvp' ); this.ui.disconnect( this ); } /** * Loads the RL module defined for a given file extension, if any * * @param {string} extension File extension * @return {jQuery.Promise} */ loadExtensionPlugins( extension ) { const deferred = $.Deferred(); const config = this.config.extensions(); if ( !( extension in config ) || config[ extension ] === 'default' ) { return deferred.resolve(); } mw.loader.using( config[ extension ], () => { deferred.resolve(); } ); return deferred; } } /** * Image loading progress. Keyed by image (database) name + '|' + thumbnail width in pixels, * value is a number between 0-100. * * @private * @property {Object.} */ MultimediaViewer.prototype.progressCache = {}; /** * Preload this many prev/next images to speed up navigation. * (E.g. preloadDistance = 3 means that the previous 3 and the next 3 images will be loaded.) * Preloading only happens when the viewer is open. * * @property {number} */ MultimediaViewer.prototype.preloadDistance = 1; /** * Stores image metadata preloads, so they can be cancelled. * * @property {TaskQueue} */ MultimediaViewer.prototype.metadataPreloadQueue = null; /** * Stores image thumbnail preloads, so they can be cancelled. * * @property {TaskQueue} */ MultimediaViewer.prototype.thumbnailPreloadQueue = null; module.exports = { Api, Canvas, CanvasButtons, Description, Dialog, FileRepoInfo, ForeignApiRepo, ForeignDbRepo, GuessedThumbnailInfo, ImageInfo, ImageModel, ImageProvider, IwTitle, License, LightboxInterface, MetadataPanel, MetadataPanelScroller, MultimediaViewer, OptionsDialog, Permission, ProgressBar, Repo, StripeButtons, TaskQueue, Thumbnail, ThumbnailInfo, ThumbnailWidth, ThumbnailWidthCalculator, TruncatableTextField, UiElement, ViewLogger };