ableplayer/scripts/buildplayer.js at develop · ableplayer/ableplayer

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import $ from 'jquery';

import DOMPurify from 'dompurify';

import validate from './validate';

import AccessibleSlider from './slider';

function addBuildplayerFunctions(AblePlayer) {

AblePlayer.prototype.injectPlayerCode = function() {

// create and inject surrounding HTML structure

// If iOS & video:

// iOS does not support any of the player's functionality - everything plays in its own player

// Therefore, AblePlayer is not loaded & all functionality is disabled

// (this all determined. If this is iOS && video, this function is never called)

var captionsContainer;

// Wrappers, from inner to outer:

// $mediaContainer - contains the original media element

// $ableDiv - contains the media player and all its objects (e.g., captions, controls, descriptions)

// $ableWrapper - contains additional widgets (e.g., transcript window, sign window)

this.$mediaContainer = this.$media.wrap('<div class="able-media-container"></div>').parent();

this.$ableDiv = this.$mediaContainer.wrap('<div class="able"></div>').parent();

this.$ableWrapper = this.$ableDiv.wrap('<div class="able-wrapper"></div>').parent();

this.$ableWrapper.addClass('able-skin-' + this.skin);

if (this.mediaType === 'video') {

// youtube adds its own big play button

// don't show ours *unless* video has a poster attribute

// (which obstructs the YouTube poster & big play button)

if (this.player !== 'youtube' || this.hasPoster) {

this.injectBigPlayButton();

}

// add container that captions or description will be appended to

// Note: new Jquery object must be assigned _after_ wrap, hence the temp captionsContainer variable

captionsContainer = $('<div>');

if (this.mediaType === 'video') {

captionsContainer.addClass('able-vidcap-container');

} else if (this.mediaType === 'audio') {

captionsContainer.addClass('able-audcap-container');

// hide this by default. It will be shown if captions are available

captionsContainer.addClass('captions-off');

}

this.injectPlayerControlArea(); // this may need to be injected after captions???

this.$captionsContainer = this.$mediaContainer.wrap(captionsContainer).parent();

this.injectAlert(this.$ableDiv);

this.injectPlaylist();

this.injectAudioPoster();

// Do this last, as it should be prepended to the top of this.$ableDiv

// after everything else has prepended

this.injectOffscreenHeading();

};

AblePlayer.prototype.injectAudioPoster = function() {

if ( this.mediaType === 'audio' && this.hasPoster ) {

const audioPoster = DOMPurify.sanitize(this.audioPoster);

const audioPosterAlt = DOMPurify.sanitize(this.audioPosterAlt);

let audioPosterImg = document.createElement( 'img' );

audioPosterImg.setAttribute( 'src', audioPoster );

audioPosterImg.setAttribute( 'alt', audioPosterAlt );

this.$audioWrapper = this.$playerDiv.wrap( '<div class="able-audio-wrapper">' ).parent();

this.$audioWrapper.prepend( audioPosterImg );

}

AblePlayer.prototype.injectOffscreenHeading = function () {

// Inject an offscreen heading to the media container.

// If heading hasn't already been manually defined via data-heading-level,

// automatically assign a level that is one level deeper than the closest parent heading

// as determined by getNextHeadingLevel()

var headingType;

if (this.playerHeadingLevel == '0') {

// do NOT inject a heading (at author's request)

} else {

if (typeof this.playerHeadingLevel === 'undefined') {

this.playerHeadingLevel = this.getNextHeadingLevel(this.$ableDiv); // returns in integer 1-6

}

headingType = 'h' + this.playerHeadingLevel.toString();

this.$headingDiv = $('<' + headingType + '>');

this.$ableDiv.prepend(this.$headingDiv);

this.$headingDiv.addClass('able-offscreen');

this.$headingDiv.text( this.translate( 'playerHeading', 'Media player' ) );

}

};

AblePlayer.prototype.injectBigPlayButton = function () {

var thisObj = this;

this.$bigPlayButton = $('<button>', {

'class': 'able-big-play-button',

'aria-hidden': false,

'aria-label': this.translate( 'play', 'Play' ),

'type': 'button',

'tabindex': 0

});

this.getIcon( this.$bigPlayButton, 'play' );

this.$bigPlayButton.on( 'click', function () {

thisObj.handlePlay();

});

this.$mediaContainer.append(this.$bigPlayButton);

};

AblePlayer.prototype.injectPlayerControlArea = function () {

this.$playerDiv = $('<div>', {

'class' : 'able-player',

'role' : 'region',

'aria-label' : ( 'audio' === this.mediaType ) ? this.translate( 'audioPlayer', 'audio player' ) : this.translate( 'videoPlayer', 'video player' )

});

this.$playerDiv.addClass('able-' + this.mediaType);

if (this.hasPlaylist && this.showNowPlaying) {

this.$nowPlayingDiv = $('<div>',{

'class' : 'able-now-playing',

'aria-live' : 'assertive',

'aria-atomic': 'true'

});

}

this.$controllerDiv = $('<div>',{

'class' : 'able-controller'

});

this.$controllerDiv.addClass('able-' + this.iconColor + '-controls');

this.$statusBarDiv = $('<div>',{

'class' : 'able-status-bar'

});

this.$timer = $('<span>',{

'class' : 'able-timer'

});

this.$elapsedTimeContainer = $('<span>',{

'class': 'able-elapsedTime',

text: '0:00'

});

this.$durationContainer = $('<span>',{

'class': 'able-duration'

});

this.$timer.append(this.$elapsedTimeContainer).append(this.$durationContainer);

this.$speed = $('<span>',{

'class' : 'able-speed',

'aria-live' : 'assertive',

'aria-atomic' : 'true'

}).text(this.translate( 'speed', 'Speed' ) + ': 1x');

this.$status = $('<span>',{

'class' : 'able-status',

'aria-live' : 'polite'

});

// Put everything together.

this.$statusBarDiv.append(this.$timer, this.$speed, this.$status);

if (this.showNowPlaying) {

this.$playerDiv.append(this.$nowPlayingDiv, this.$controllerDiv, this.$statusBarDiv);

} else {

this.$playerDiv.append(this.$controllerDiv, this.$statusBarDiv);

}

if (this.mediaType === 'video') {

// the player controls go after the media & captions

this.$ableDiv.append(this.$playerDiv);

} else {

// the player controls go before the media & captions

this.$ableDiv.prepend(this.$playerDiv);

}

};

AblePlayer.prototype.injectTextDescriptionArea = function () {

// create a div for writing description text

this.$descDiv = $('<div>',{

'class': 'able-descriptions'

});

// Add ARIA so description will be announced by screen readers

// Later (in description.js > showDescription()),

// if browser supports Web Speech API and this.descMethod === 'browser'

// these attributes will be removed

this.$descDiv.attr({

'aria-live': 'assertive',

'aria-atomic': 'true'

});

// Start off with description hidden.

// It will be exposed conditionally within description.js > initDescription()

this.$descDiv.hide();

this.$ableDiv.append(this.$descDiv);

};

AblePlayer.prototype.getDefaultWidth = function(which) {

let viewportMaxwidth = window.innerWidth;

// return default width of resizable elements

// these values are somewhat arbitrary, but seem to result in good usability

// if users disagree, they can resize (and resposition) them

if (which === 'transcript') {

return ( viewportMaxwidth <= 450 ) ? viewportMaxwidth : 450;

} else if (which === 'sign') {

return ( viewportMaxwidth <= 400 ) ? viewportMaxwidth : 400;

}

};

/**

* Reposition draggable windows when switched into fullscreen.

* @param {string} which 'transcript' or 'sign'.

AblePlayer.prototype.rePositionDraggableWindow = function (which) {

let preferences, $window;

preferences = this.getPref();

$window = ( which === 'transcript' ) ? this.$transcriptArea : this.$signWindow;

console.log( $window );

if ( which === 'transcript' && $window ) {

if (typeof preferences.transcript !== 'undefined') {

this.prevTranscriptPosition = preferences.transcript;

}

$window.css({

'top': 0,

'left': 0

});

} else if ( 'sign' === which && $window ) {

if (typeof preferences.sign !== 'undefined') {

this.prevSignPosition = preferences.sign;

}

$window.css({

'top': 0,

'right': 0,

'left': 'auto'

});

}

AblePlayer.prototype.positionDraggableWindow = function (which, width) {

// which is either 'transcript' or 'sign'

var preferences, preferencePos, $window, windowPos, viewportWidth, windowWidth;

preferences = this.getPref();

$window = ( which === 'transcript' ) ? this.$transcriptArea : this.$signWindow;

if ( ! $window ) {

return;

}

if (which === 'transcript') {

if (typeof preferences.transcript !== 'undefined') {

preferencePos = preferences.transcript;

}

if ( this.prevTranscriptPosition ) {

preferencePos = this.prevTranscriptPosition;

this.prevTranscriptPosition = false;

}

} else if (which === 'sign') {

if (typeof preferences.sign !== 'undefined') {

preferencePos = preferences.sign;

}

if ( this.prevSignPosition ) {

preferencePos = this.prevSignPosition;

this.prevSignPosition = false;

}

if (typeof preferencePos !== 'undefined' && !($.isEmptyObject(preferencePos))) {

// position window using stored values from preferences

$window.css({

'position': preferencePos['position'],

'width': preferencePos['width'],

'z-index': preferencePos['zindex']

});

if (preferencePos['position'] === 'absolute') {

$window.css({

'top': preferencePos['top'],

'left': preferencePos['left']

});

// Check whether the window is above the top of the viewport.

let topPosition = $window.offset().top;

let leftPosition = $window.offset().left;

viewportWidth = window.innerWidth;

windowWidth = $window.width();

if ( topPosition < 0 ) {

$window.css({

'top': preferencePos['top'] - topPosition

});

}

// If draggable window is off screen to the left.

if ( leftPosition < 0 && ! this.restoringAfterFullscreen ) {

console.log( leftPosition );

$window.css({

'left': preferencePos['left'] - leftPosition

});

}

// If draggable window is off screen to the right.

if ( viewportWidth - leftPosition < 30 ) {

$window.css({

'left': viewportWidth - windowWidth

});

}

// since preferences are not page-specific, z-index needs may vary across different pages

this.updateZIndex(which);

} else {

// position window using default values

windowPos = this.getOptimumPosition(which, width);

if (typeof width === 'undefined') {

width = this.getDefaultWidth(which);

}

$window.css({

'position': windowPos[0],

'width': width,

'z-index': windowPos[3]

});

if (windowPos[0] === 'absolute') {

$window.css({

'top': windowPos[1] + 'px',

'left': windowPos[2] + 'px',

});

}

};

AblePlayer.prototype.getOptimumPosition = function (targetWindow, targetWidth) {

// returns optimum position for targetWindow, as an array with the following structure:

// 0 - CSS position ('absolute' or 'relative')

// 1 - top

// 2 - left

// 3 - zindex (if not default)

// targetWindow is either 'transcript' or 'sign'

// if there is room to the right of the player, position element there

// else if there is room the left of the player, position element there

// else position element beneath player

var gap, position, ableWidth, ableOffset, ableLeft, windowWidth, otherWindowWidth;

if (typeof targetWidth === 'undefined') {

targetWidth = this.getDefaultWidth(targetWindow);

}

gap = 5; // number of pixels to preserve between Able Player objects

position = []; // position, top, left

ableWidth = this.$ableDiv.width();

ableOffset = this.$ableDiv.offset();

ableLeft = ableOffset.left;

windowWidth = $(window).width();

otherWindowWidth = 0; // width of other visiable draggable windows will be added to this

if (targetWindow === 'transcript') {

// If placing the transcript window, check position of sign window first.

if (typeof this.$signWindow !== 'undefined' && (this.$signWindow.is(':visible'))) {

otherWindowWidth = this.$signWindow.width() + gap;

}

} else if (targetWindow === 'sign') {

// If placing the sign window, check position of transcript window first.

if (typeof this.$transcriptArea !== 'undefined' && (this.$transcriptArea.is(':visible'))) {

otherWindowWidth = this.$transcriptArea.width() + gap;

}

if (targetWidth < (windowWidth - (ableLeft + ableWidth + gap + otherWindowWidth))) {

// there's room to the left of $ableDiv

position[0] = 'absolute';

position[1] = 0;

position[2] = ableWidth + otherWindowWidth + gap;

} else if (targetWidth + gap < ableLeft) {

// there's room to the right of $ableDiv

position[0] = 'absolute';

position[1] = 0;

position[2] = ableLeft - targetWidth - gap;

} else {

// position element below $ableDiv

position[0] = 'relative';

// no need to define top, left, or z-index

}

return position;

};

AblePlayer.prototype.injectAlert = function ($container) {

// inject two alerts, one visible for all users and one for screen reader users only

this.$alertBox = $('<div role="alert"></div>');

this.$alertBox.addClass('able-alert');

this.$alertBox.hide();

var $alertText = $( '<span></span>' );

$alertText.appendTo(this.$alertBox);

var $alertDismiss = $('<button type="button"></button>' );

$alertDismiss.attr( 'aria-label', this.translate( 'dismissButton', 'Dismiss' ) );

$alertDismiss.text( '×' );

$alertDismiss.appendTo(this.$alertBox);

$alertDismiss.on( 'click', function(e) {

$(this).parent('div').hide();

});

this.$alertBox.appendTo($container);

if ( ! this.$srAlertBox ) {

this.$srAlertBox = $('<div role="alert"></div>');

this.$srAlertBox.addClass('able-screenreader-alert');

this.$srAlertBox.appendTo($container);

}

};

AblePlayer.prototype.injectPlaylist = function () {

if (this.playlistEmbed === true) {

// move playlist into player, immediately before statusBarDiv

var playlistClone = this.$playlistDom.clone();

playlistClone.insertBefore(this.$statusBarDiv);

// Update to the new playlist copy.

this.$playlist = playlistClone.find('li');

}

};

AblePlayer.prototype.createPopup = function (which, tracks) {

// Create popup menu and append to player

// 'which' parameter is either 'captions', 'chapters', 'prefs', 'transcript-window' or 'sign-window'

// 'tracks', if provided, is a list of tracks to be used as menu items

var thisObj, $menu, includeMenuItem, i, $menuItem, prefCat, whichPref, hasDefault, track,

windowOptions, $thisItem, $prevItem, $nextItem, hasDescription, hasTranscript;

thisObj = this;

$menu = $('<ul>',{

'id': this.mediaId + '-' + which + '-menu',

'class': 'able-popup',

'role': 'menu'

}).hide();

if (which === 'captions') {

$menu.addClass('able-popup-captions');

}

// Populate menu with menu items

if (which === 'prefs') {

if (this.prefCats.length > 1) {

for (i = 0; i < this.prefCats.length; i++) {

prefCat = this.prefCats[i];

hasDescription = ( thisObj.hasDescTracks || thisObj.hasOpenDesc || thisObj.hasClosedDesc ) ? true : false;

hasTranscript = ( thisObj.transcriptType === null ) ? false : true;

// If this player does not have descriptions or transcripts, do not output that option preferences.

if ( prefCat === 'descriptions' && ! hasDescription || prefCat === 'transcript' && ! hasTranscript ) {

continue;

}

$menuItem = $('<li></li>',{

'role': 'menuitem',

'tabindex': '-1'

});

if (prefCat === 'captions') {

$menuItem.text( this.translate( 'prefMenuCaptions', 'Captions' ) );

} else if (prefCat === 'descriptions') {

$menuItem.text( this.translate( 'prefMenuDescriptions', 'Descriptions' ) );

} else if (prefCat === 'keyboard') {

$menuItem.text( this.translate( 'prefMenuKeyboard', 'Keyboard' ) );

} else if (prefCat === 'transcript') {

$menuItem.text( this.translate( 'prefMenuTranscript', 'Transcript' ) );

}

$menuItem.on('click',function() {

whichPref = $(this).text();

thisObj.showingPrefsDialog = true;

thisObj.setFullscreen(false);

if (whichPref === thisObj.tt.prefMenuCaptions) {

thisObj.captionPrefsDialog.show();

} else if (whichPref === thisObj.tt.prefMenuDescriptions) {

thisObj.descPrefsDialog.show();

} else if (whichPref === thisObj.tt.prefMenuKeyboard) {

thisObj.keyboardPrefsDialog.show();

} else if (whichPref === thisObj.tt.prefMenuTranscript) {

thisObj.transcriptPrefsDialog.show();

}

thisObj.closePopups();

thisObj.showingPrefsDialog = false;

});

$menu.append($menuItem);

}

this.$prefsButton.attr('data-prefs-popup','menu');

} else if (this.prefCats.length == 1) {

// only 1 category, so don't create a popup menu.

// Instead, open dialog directly when user clicks Prefs button

this.$prefsButton.attr('data-prefs-popup',this.prefCats[0]);

}

} else if (which === 'captions' || which === 'chapters') {

hasDefault = false;

for (i = 0; i < tracks.length; i++) {

track = tracks[i];

if (which === 'captions' && this.player === 'html5' && typeof track.cues === 'undefined') {

includeMenuItem = false;

} else {

includeMenuItem = true;

}

if (includeMenuItem) {

$menuItem = $('<li></li>',{

'role': 'menuitemradio',

'tabindex': '-1',

'lang': track.language

});

if (track.def && this.prefCaptions == 1) {

$menuItem.attr('aria-checked','true');

hasDefault = true;

} else {

$menuItem.attr('aria-checked','false');

}

// Get a label using track data

if (which == 'captions') {

$menuItem.text(track.label);

$menuItem.on('click',this.getCaptionClickFunction(track));

} else if (which == 'chapters') {

$menuItem.text(this.flattenCueForCaption(track) + ' - ' + this.formatSecondsAsColonTime(track.start));

$menuItem.on('click',this.getChapterClickFunction(track.start));

}

$menu.append($menuItem);

}

if (which === 'captions') {

// add a 'captions off' menu item

$menuItem = $('<li></li>',{

'role': 'menuitemradio',

'tabindex': '-1',

}).text( this.translate( 'captionsOff', 'Captions off' ) );

if (this.prefCaptions === 0) {

$menuItem.attr('aria-checked','true');

hasDefault = true;

} else {

$menuItem.attr('aria-checked','false');

}

$menuItem.on('click',this.getCaptionOffFunction());

$menu.append($menuItem);

}

} else if (which === 'transcript-window' || which === 'sign-window') {

windowOptions = [];

windowOptions.push({

'name': 'move',

'label': this.translate( 'windowMove', 'Move' )

});

windowOptions.push({

'name': 'resize',

'label': this.translate( 'windowResize', 'Resize' )

});

windowOptions.push({

'name': 'close',

'label': this.translate( 'windowClose', 'Close' )

});

for (i = 0; i < windowOptions.length; i++) {

$menuItem = $('<li></li>',{

'role': 'menuitem',

'tabindex': '-1',

'data-choice': windowOptions[i].name

});

$menuItem.text(windowOptions[i].label);

$menuItem.on('click',function(e) {

e.stopPropagation();

if (typeof e.button !== 'undefined' && e.button !== 0) {

// this was a mouse click (if click is triggered by keyboard, e.button is undefined)

// and the button was not a left click (left click = 0)

// therefore, ignore this click

return false;

}

if (!thisObj.windowMenuClickRegistered && !thisObj.finishingDrag) {

thisObj.windowMenuClickRegistered = true;

thisObj.handleMenuChoice(which.substring(0, which.indexOf('-')), $(this).attr('data-choice'), e);

}

});

$menu.append($menuItem);

}

// assign default item, if there isn't one already

if (which === 'captions' && !hasDefault) {

// check the menu item associated with the default language

// as determined in control.js > syncTrackLanguages()

if ($menu.find('li[lang=' + this.captionLang + ']')) {

// a track exists for the default language. Check that item in the menu

$menu.find('li[lang=' + this.captionLang + ']').attr('aria-checked','true');

} else {

// check the last item (captions off)

$menu.find('li').last().attr('aria-checked','true');

}

} else if (which === 'chapters') {

if ($menu.find('li:contains("' + this.defaultChapter + '")')) {

$menu.find('li:contains("' + this.defaultChapter + '")').attr('aria-checked','true').addClass('able-focus');

} else {

$menu.find('li').first().attr('aria-checked','true').addClass('able-focus');

}

// add keyboard handlers for navigating within popups

$menu.on('keydown',function (e) {

$thisItem = $(this).find('li:focus');

if ($thisItem.is(':first-child')) {

// this is the first item in the menu

$prevItem = $(this).find('li').last(); // wrap to bottom

$nextItem = $thisItem.next();

} else if ($thisItem.is(':last-child')) {

// this is the last Item

$prevItem = $thisItem.prev();

$nextItem = $(this).find('li').first(); // wrap to top

} else {

$prevItem = $thisItem.prev();

$nextItem = $thisItem.next();

}

if (e.key === 'Tab') {

if (e.shiftKey) {