/* # ----------------------------------------------------------------------------- # ~/assets/themes/j1/modules/backstretch/js/backstretch.js # Backstretch v.2.1.16 implementation for J1 Theme. # # Product/Info: # https://jekyll.one # http://srobbin.com/jquery-plugins/backstretch/ # # Copyright (C) 2023 Juergen Adams # Copyright (C) 2017 Daniel Cohen Gindi # Copyright (C) 2012 Scott Robbin # # J1 Theme is licensed under the MIT License. # See: https://github.com/jekyll-one-org/j1-template/blob/main/LICENSE.md # Backstretch is licensed under the MIT License. # See: https://github.com/danielgindi/jquery-backstretch # ----------------------------------------------------------------------------- */ // ----------------------------------------------------------------------------- // ESLint shimming // ----------------------------------------------------------------------------- /* eslint indent: "off" */ /* eslint no-unused-vars: "off" */ /* eslint no-undef: "off" */ /* eslint no-useless-escape: "off" */ /* eslint no-prototype-builtins: "off" */ /* eslint no-shadow-restricted-names: "off" */ // ----------------------------------------------------------------------------- // Version 2.1.16 'use strict'; (function ($, window, undefined) { /** @const */ var YOUTUBE_REGEXP = /^.*(youtu\.be\/|youtube\.com\/v\/|youtube\.com\/embed\/|youtube\.com\/watch\?v=|youtube\.com\/watch\?.*\&v=)([^#\&\?]*).*/i; var logText; /* PLUGIN DEFINITION * ========================= */ $.fn.backstretch = function (images, options) { var args = arguments; // var debug = false; /* * Scroll the page one pixel to get the right window height on iOS * Pretty harmless for everyone else */ if ($(window).scrollTop() === 0) { window.scrollTo(0, 0); } var returnValues; this.each(function (eachIndex) { var $this = $(this), obj = $this.data('backstretch'); // Do we already have an instance attached to this element? if (obj) { // Is this a method they're trying to execute? if (typeof args[0] === 'string' && typeof obj[args[0]] === 'function') { // Call the method var returnValue = obj[args[0]].apply(obj, Array.prototype.slice.call(args, 1)); if (returnValue === obj) { // If a method is chaining returnValue = undefined; } if (returnValue !== undefined) { returnValues = returnValues || []; returnValues[eachIndex] = returnValue; } return; // Nothing further to do } // Merge the old options with the new options = $.extend(obj.options, options); // Remove the old instance if (obj.hasOwnProperty('destroy')) { obj.destroy(true); } } // We need at least one image if (!images || (images && images.length === 0)) { var cssBackgroundImage = $this.css('background-image'); if (cssBackgroundImage && cssBackgroundImage !== 'none') { images = [{ url: $this.css('backgroundImage').replace(/url\(|\)|"|'/g, '') }]; } else { $.error('No images were supplied for Backstretch, or element must have a CSS-defined background image.'); } } obj = new Backstretch(this, images, options || {}); $this.data('backstretch', obj); }); return returnValues ? returnValues.length === 1 ? returnValues[0] : returnValues : this; }; // If no element is supplied, we'll attach to body $.backstretch = function (images, options) { // Return the instance return $('body') .backstretch(images, options) .data('backstretch'); }; // Custom selector $.expr[':'].backstretch = function (elem) { return $(elem).data('backstretch') !== undefined; }; /* DEFAULTS * ========================= */ $.fn.backstretch.defaults = { debug: false , duration: 5000 // Amount of time in between slides (if slideshow) , transition: 'fade' // Type of transition between slides , transitionDuration: 0 // Duration of transition between slides , animateFirst: true // Animate the transition of first image of slideshow in? , alignX: 0.5 // The x-alignment for the image, can be 'left'|'center'|'right' or any number between 0.0 and 1.0 , alignY: 0.5 // The y-alignment for the image, can be 'top'|'center'|'bottom' or any number between 0.0 and 1.0 , paused: false // Whether the images should slide after given duration , start: 0 // Index of the first image to show , preload: 2 // How many images preload at a time? , preloadSize: 1 // How many images can we preload in parallel? , resolutionRefreshRate: 2500 // How long to wait before switching resolution? , resolutionChangeRatioThreshold: 0.1 // How much a change should it be before switching resolution? }; /* STYLES * * Baked-in styles that we'll apply to our elements. * In an effort to keep the plugin simple, these are not exposed as options. * That said, anyone can override these in their own stylesheet. * ========================= */ var styles = { wrap: { left: 0, top: 0, overflow: 'hidden', margin: 0, padding: 0, height: '100%', width: '100%', zIndex: -999999 }, itemWrapper: { position: 'absolute', display: 'none', margin: 0, padding: 0, border: 'none', width: '100%', height: '100%', zIndex: -999999 }, item: { position: 'absolute', margin: 0, padding: 0, border: 'none', width: '100%', height: '100%', maxWidth: 'none' } }; /* Given an array of different options for an image, * choose the optimal image for the container size. * * Given an image template (a string with {{ width }} and/or * {{height}} inside) and a container object, returns the * image url with the exact values for the size of that * container. * * Returns an array of urls optimized for the specified resolution. * */ var optimalSizeImages = (function () { /* Sorts the array of image sizes based on width */ var widthInsertSort = function (arr) { for (var i = 1; i < arr.length; i++) { var tmp = arr[i], j = i; while (arr[j - 1] && parseInt(arr[j - 1].width, 10) > parseInt(tmp.width, 10)) { arr[j] = arr[j - 1]; --j; } arr[j] = tmp; } return arr; }; /* Given an array of various sizes of the same image and a container width, * return the best image. */ var selectBest = function (containerWidth, containerHeight, imageSizes) { var devicePixelRatio = window.devicePixelRatio || 1; var deviceOrientation = getDeviceOrientation(); var windowOrientation = getWindowOrientation(); var wrapperOrientation = (containerHeight > containerWidth) ? 'portrait' : (containerWidth > containerHeight ? 'landscape' : 'square'); var lastAllowedImage = 0; var testWidth; for (var j = 0, image; j < imageSizes.length; j++) { image = imageSizes[j]; // In case a new image was pushed in, process it: if (typeof image === 'string') { image = imageSizes[j] = { url: image }; } if (image.pixelRatio && image.pixelRatio !== 'auto' && parseFloat(image.pixelRatio) !== devicePixelRatio) { // We disallowed choosing this image for current device pixel ratio, // So skip this one. continue; } if (image.deviceOrientation && image.deviceOrientation !== deviceOrientation) { // We disallowed choosing this image for current device orientation, // So skip this one. continue; } if (image.windowOrientation && image.windowOrientation !== deviceOrientation) { // We disallowed choosing this image for current window orientation, // So skip this one. continue; } if (image.orientation && image.orientation !== wrapperOrientation) { // We disallowed choosing this image for current element's orientation, // So skip this one. continue; } // Mark this one as the last one we investigated // which does not violate device pixel ratio rules. // We may choose this one later if there's no match. lastAllowedImage = j; // For most images, we match the specified width against element width, // And enforcing a limit depending on the "pixelRatio" property if specified. // But if a pixelRatio="auto", then we consider the width as the physical width of the image, // And match it while considering the device's pixel ratio. testWidth = containerWidth; if (image.pixelRatio === 'auto') { containerWidth *= devicePixelRatio; } // Stop when the width of the image is larger or equal to the container width if (image.width >= testWidth) { break; } } // Use the image located at where we stopped return imageSizes[Math.min(j, lastAllowedImage)]; }; var replaceTagsInUrl = function (url, templateReplacer) { if (typeof url === 'string') { url = url.replace(/{{(width|height)}}/g, templateReplacer); } else if (url instanceof Array) { for (var i = 0; i < url.length; i++) { if (url[i].src) { url[i].src = replaceTagsInUrl(url[i].src, templateReplacer); } else { url[i] = replaceTagsInUrl(url[i], templateReplacer); } } } return url; }; return function ($container, images) { var containerWidth = $container.width(), containerHeight = $container.height(); var chosenImages = []; var templateReplacer = function (match, key) { if (key === 'width') { return containerWidth; } if (key === 'height') { return containerHeight; } return match; }; for (var i = 0; i < images.length; i++) { if ($.isArray(images[i])) { images[i] = widthInsertSort(images[i]); var chosen = selectBest(containerWidth, containerHeight, images[i]); chosenImages.push(chosen); } else { // In case a new image was pushed in, process it: if (typeof images[i] === 'string') { images[i] = { url: images[i] }; } var item = $.extend({}, images[i]); item.url = replaceTagsInUrl(item.url, templateReplacer); chosenImages.push(item); } } return chosenImages; }; })(); var isVideoSource = function (source) { return YOUTUBE_REGEXP.test(source.url) || source.isVideo; }; /* Preload images */ var preload = (function (sources, startAt, count, batchSize, callback) { // Plugin cache var cache = []; // Wrapper for cache var caching = function (image) { for (var i = 0; i < cache.length; i++) { if (cache[i].src === image.src) { return cache[i]; } } cache.push(image); return image; }; // Execute callback var exec = function (sources, callback, last) { if (typeof callback === 'function') { callback.call(sources, last); } }; // Closure to hide cache return function preload(sources, startAt, count, batchSize, callback) { // Check input data if (typeof sources === 'undefined') { return; } if (!$.isArray(sources)) { sources = [sources]; } if (arguments.length < 5 && typeof arguments[arguments.length - 1] === 'function') { callback = arguments[arguments.length - 1]; } startAt = (typeof startAt === 'function' || !startAt) ? 0 : startAt; count = (typeof count === 'function' || !count || count < 0) ? sources.length : Math.min(count, sources.length); batchSize = (typeof batchSize === 'function' || !batchSize) ? 1 : batchSize; if (startAt >= sources.length) { startAt = 0; count = 0; } if (batchSize < 0) { batchSize = count; } batchSize = Math.min(batchSize, count); var next = sources.slice(startAt + batchSize, count - batchSize); sources = sources.slice(startAt, batchSize); count = sources.length; // If sources array is empty if (!count) { exec(sources, callback, true); return; } // Image loading callback var countLoaded = 0; var loaded = function () { countLoaded++; if (countLoaded !== count) { return; } exec(sources, callback, !next); preload(next, 0, 0, batchSize, callback); }; // Loop sources to preload var image; for (var i = 0; i < sources.length; i++) { if (isVideoSource(sources[i])) { // Do not preload videos. There are issues with that. // First - we need to keep an instance of the preloaded and use that exactly, not a copy. // Second - there are memory issues. // If there will be a requirement from users - I'll try to implement this. continue; } else { image = new Image(); image.src = sources[i].url; image = caching(image); if (image.complete) { loaded(); } else { $(image).on('load error', loaded); } } } }; })(); /* Process images array */ var processImagesArray = function (images) { var processed = []; for (var i = 0; i < images.length; i++) { if (typeof images[i] === 'string') { processed.push({ url: images[i] }); } else if ($.isArray(images[i])) { processed.push(processImagesArray(images[i])); } else { processed.push(processOptions(images[i])); } } return processed; }; /* Process options */ var processOptions = function (options, required) { // Convert old options // centeredX/centeredY are deprecated if (options.centeredX || options.centeredY) { if (window.console && window.console.log) { window.console.log('jquery.backstretch: `centeredX`/`centeredY` is deprecated, please use `alignX`/`alignY`'); } if (options.centeredX) { options.alignX = 0.5; } if (options.centeredY) { options.alignY = 0.5; } } // Deprecated spec if (options.speed !== undefined) { if (window.console && window.console.log) { window.console.log('jquery.backstretch: `speed` is deprecated, please use `transitionDuration`'); } options.transitionDuration = options.speed; options.transition = 'fade'; } // Typo if (options.resolutionChangeRatioTreshold !== undefined) { window.console.log('jquery.backstretch: `treshold` is a typo!'); options.resolutionChangeRatioThreshold = options.resolutionChangeRatioTreshold; } // Current spec that needs processing if (options.fadeFirst !== undefined) { options.animateFirst = options.fadeFirst; } if (options.fade !== undefined) { options.transitionDuration = options.fade; options.transition = 'fade'; } if (options.scale) { options.scale = validScale(options.scale); } return processAlignOptions(options); }; /* Process align options */ var processAlignOptions = function (options, required) { if (options.alignX === 'left') { options.alignX = 0.0; } else if (options.alignX === 'center') { options.alignX = 0.5; } else if (options.alignX === 'right') { options.alignX = 1.0; } else { if (options.alignX !== undefined || required) { options.alignX = parseFloat(options.alignX); if (isNaN(options.alignX)) { options.alignX = 0.5; } } } if (options.alignY === 'top') { options.alignY = 0.0; } else if (options.alignY === 'center') { options.alignY = 0.5; } else if (options.alignY === 'bottom') { options.alignY = 1.0; } else { if (options.alignX !== undefined || required) { options.alignY = parseFloat(options.alignY); if (isNaN(options.alignY)) { options.alignY = 0.5; } } } return options; }; var SUPPORTED_SCALE_OPTIONS = { 'cover': 'cover', 'fit': 'fit', 'fit-smaller': 'fit-smaller', 'fill': 'fill' }; function validScale(scale) { if (!SUPPORTED_SCALE_OPTIONS.hasOwnProperty(scale)) { return 'cover'; } return scale; } /* CLASS DEFINITION * ========================= */ var Backstretch = function (container, images, options) { this.options = $.extend({}, $.fn.backstretch.defaults, options || {}); this.firstShow = true; // Process options processOptions(this.options, true); /* In its simplest form, we allow Backstretch to be called on an image path. * e.g. $.backstretch('/path/to/image.jpg') * So, we need to turn this back into an array. */ this.images = processImagesArray($.isArray(images) ? images : [images]); /** * Paused-Option */ if (this.options.paused) { this.paused = true; } /** * Start-Option (Index) */ if (this.options.start >= this.images.length) { this.options.start = this.images.length - 1; } if (this.options.start < 0) { this.options.start = 0; } // Convenience reference to know if the container is body. this.isBody = container === document.body; /* We're keeping track of a few different elements * * Container: the element that Backstretch was called on. * Wrap: a DIV that we place the image into, so we can hide the overflow. * Root: Convenience reference to help calculate the correct height. */ var $window = $(window); this.$container = $(container); this.$root = this.isBody ? supportsFixedPosition ? $window : $(document) : this.$container; this.originalImages = this.images; this.images = optimalSizeImages( this.options.alwaysTestWindowResolution ? $window : this.$root, this.originalImages); /** * Pre-Loading. * This is the first image, so we will preload a minimum of 1 images. */ preload(this.images, this.options.start || 0, this.options.preload || 1); // Don't create a new wrap if one already exists (from a previous instance of Backstretch) var $existing = this.$container.children('.backstretch').first(); this.$wrap = $existing.length ? $existing : $('
') .css(this.options.bypassCss ? {} : styles.wrap) .appendTo(this.$container); if (!this.options.bypassCss) { // Non-body elements need some style adjustments if (!this.isBody) { // If the container is statically positioned, we need to make it relative, // and if no zIndex is defined, we should set it to zero. var position = this.$container.css('position'), zIndex = this.$container.css('zIndex'); this.$container.css({ position: position === 'static' ? 'relative' : position, zIndex: zIndex === 'auto' ? 0 : zIndex }); // Needs a higher z-index this.$wrap.css({ zIndex: -999998 }); } // Fixed or absolute positioning? this.$wrap.css({ position: this.isBody && supportsFixedPosition ? 'fixed' : 'absolute' }); } // Set the first image this.index = this.options.start; this.show(this.index); // Listen for resize $window.on('resize.backstretch', $.proxy(this.resize, this)) .on('orientationchange.backstretch', $.proxy(function () { // Need to do this in order to get the right window height if (this.isBody && window.pageYOffset === 0) { window.scrollTo(0, 1); this.resize(); } }, this)); }; var performTransition = function (options) { var transition = options.transition || 'fade'; // Look for multiple options if (typeof transition === 'string' && transition.indexOf('|') > -1) { transition = transition.split('|'); } if (transition instanceof Array) { transition = transition[Math.round(Math.random() * (transition.length - 1))]; } var $new = options['new']; var $old = options['old'] ? options['old'] : $([]); switch (transition.toString().toLowerCase()) { default: case 'fade': $new.fadeIn({ duration: options.duration, complete: options.complete, easing: options.easing || undefined }); break; case 'fadeinout': case 'fade_in_out': var fadeInNew = function () { $new.fadeIn({ duration: options.duration / 2, complete: options.complete, easing: options.easing || undefined }); }; if ($old.length) { $old.fadeOut({ duration: options.duration / 2, complete: fadeInNew, easing: options.easing || undefined }); } else { fadeInNew(); } break; case 'pushleft': case 'push_left': case 'pushright': case 'push_right': case 'pushup': case 'push_up': case 'pushdown': case 'push_down': case 'coverleft': case 'cover_left': case 'coverright': case 'cover_right': case 'coverup': case 'cover_up': case 'coverdown': case 'cover_down': var transitionParts = transition.match(/^(cover|push)_?(.*)$/); var animProp = transitionParts[2] === 'left' ? 'right' : transitionParts[2] === 'right' ? 'left' : transitionParts[2] === 'down' ? 'top' : transitionParts[2] === 'up' ? 'bottom' : 'right'; var newCssStart = { 'display': '' }, newCssAnim = {}; newCssStart[animProp] = '-100%'; newCssAnim[animProp] = 0; $new .css(newCssStart) .animate(newCssAnim, { duration: options.duration, complete: function () { $new.css(animProp, ''); options.complete.apply(this, arguments); }, easing: options.easing || undefined }); if (transitionParts[1] === 'push' && $old.length) { var oldCssAnim = {}; oldCssAnim[animProp] = '100%'; $old .animate(oldCssAnim, { duration: options.duration, complete: function () { $old.css('display', 'none'); }, easing: options.easing || undefined }); } break; } }; /* PUBLIC METHODS * ========================= */ Backstretch.prototype = { resize: function () { try { // var debug = false; var logger = log4javascript.getLogger('j1.core.attic'); // Check for a better suited image after the resize var $resTest = this.options.alwaysTestWindowResolution ? $(window) : this.$root; var newContainerWidth = $resTest.width(); var newContainerHeight = $resTest.height(); var changeRatioW = newContainerWidth / (this._lastResizeContainerWidth || 0); var changeRatioH = newContainerHeight / (this._lastResizeContainerHeight || 0); var resolutionChangeRatioThreshold = this.options.resolutionChangeRatioThreshold || 0.0; // check for big changes in container size if ((newContainerWidth !== this._lastResizeContainerWidth || newContainerHeight !== this._lastResizeContainerHeight) && ((Math.abs(changeRatioW - 1) >= resolutionChangeRatioThreshold || isNaN(changeRatioW)) || (Math.abs(changeRatioH - 1) >= resolutionChangeRatioThreshold || isNaN(changeRatioH)))) { this._lastResizeContainerWidth = newContainerWidth; this._lastResizeContainerHeight = newContainerHeight; // Big change: rebuild the entire images array this.images = optimalSizeImages($resTest, this.originalImages); // Preload them (they will be automatically inserted on the next cycle) if (this.options.preload) { preload(this.images, (this.index + 1) % this.images.length, this.options.preload); } // In case there is no cycle and the new source is different than the current if (this.images.length === 1 && this._currentImage.url !== this.images[0].url) { // Wait a little an update the image being showed var that = this; clearTimeout(that._selectAnotherResolutionTimeout); that._selectAnotherResolutionTimeout = setTimeout(function () { that.show(0); }, this.options.resolutionRefreshRate); } } var bgCSS = { left: 0, top: 0, right: 'auto', bottom: 'auto' } , boxWidth = this.isBody ? this.$root.width() : this.$root.innerWidth(), boxHeight = this.isBody ? (window.innerHeight ? window.innerHeight : this.$root.height()) : this.$root.innerHeight() , naturalWidth = this.$itemWrapper.data('width'), naturalHeight = this.$itemWrapper.data('height') , ratio = (naturalWidth / naturalHeight) || 1 , alignX = this._currentImage.alignX === undefined ? this.options.alignX : this._currentImage.alignX, alignY = this._currentImage.alignY === undefined ? this.options.alignY : this._currentImage.alignY, scale = validScale(this._currentImage.scale || this.options.scale); // jadams, 2017-12-07: Added log for testing if(this.options.debug) { logText = '\n' + 'resize: boxHeight x boxWidth: ' + boxHeight + ' x ' + boxWidth; logger.debug(logText); } // if ( boxHeight == 0 || boxWidth == 0 ) { // logText = '\n' + 'Kacke am Schuh'; // logger.warn(logText); // } var width, height; if (scale === 'fit' || scale === 'fit-smaller') { width = naturalWidth; height = naturalHeight; if (width > boxWidth || height > boxHeight || scale === 'fit-smaller') { var boxRatio = boxWidth / boxHeight; if (boxRatio > ratio) { width = Math.floor(boxHeight * ratio); height = boxHeight; } else if (boxRatio < ratio) { width = boxWidth; height = Math.floor(boxWidth / ratio); } else { width = boxWidth; height = boxHeight; } } } else if (scale === 'fill') { width = boxWidth; height = boxHeight; } else { // 'cover' width = Math.max(boxHeight * ratio, boxWidth); height = Math.max(width / ratio, boxHeight); } // Make adjustments based on image ratio bgCSS.top = -(height - boxHeight) * alignY; bgCSS.left = -(width - boxWidth) * alignX; bgCSS.width = width; bgCSS.height = height; if (!this.options.bypassCss) { this.$wrap .css({ width: boxWidth, height: boxHeight }) .find('>.backstretch-item').not('.deleteable') .each(function () { var $wrapper = $(this); $wrapper.find('img,video,iframe') .css(bgCSS); }); } var evt = $.Event('backstretch.resize', { relatedTarget: this.$container[0] }); this.$container.trigger(evt, this); } catch (err) { // IE7 seems to trigger resize before the image is loaded. // This try/catch block is a hack to let it fail gracefully. logText = 'resize: jadams, IE7 hack to let it fail gracefully: ' + err; logger.warn(logText); } return this; } // Show the slide at a certain position , show: function (newIndex, overrideOptions) { var logger = log4javascript.getLogger('j1.core.attic'); // Validate index if (Math.abs(newIndex) > this.images.length - 1) { return; } // Vars var that = this, $oldItemWrapper = that.$wrap.find('>.backstretch-item').addClass('deleteable'), oldVideoWrapper = that.videoWrapper, evtOptions = { relatedTarget: that.$container[0] }; // Trigger the "before" event that.$container.trigger($.Event('backstretch.before', evtOptions), [that, newIndex]); // Set the new frame index this.index = newIndex; var selectedImage = that.images[newIndex]; // Pause the slideshow clearTimeout(that._cycleTimeout); // New image delete that.videoWrapper; // Current item may not be a video var isVideo = isVideoSource(selectedImage); if (isVideo) { that.videoWrapper = new VideoWrapper(selectedImage); that.$item = that.videoWrapper.$video.css('pointer-events', 'none'); } else { that.$item = $(''); } that.$itemWrapper = $('