import { isBlacklisted, isEnabled } from './playlist.js';
/**
* Enable/disable playlist function. It is intended to have the first two
* arguments partially-applied in order to create the final per-playlist
* function.
*
* @param {PlaylistLoader} playlist - The rendition or media-playlist
* @param {Function} changePlaylistFn - A function to be called after a
* playlist's enabled-state has been changed. Will NOT be called if a
* playlist's enabled-state is unchanged
* @param {Boolean=} enable - Value to set the playlist enabled-state to
* or if undefined returns the current enabled-state for the playlist
* @return {Boolean} The current enabled-state of the playlist
*/
const enableFunction = (loader, playlistUri, changePlaylistFn, enable) => {
const playlist = loader.master.playlists[playlistUri];
const blacklisted = isBlacklisted(playlist);
const currentlyEnabled = isEnabled(playlist);
if (typeof enable === 'undefined') {
return currentlyEnabled;
}
if (enable) {
delete playlist.disabled;
} else {
playlist.disabled = true;
}
if (enable !== currentlyEnabled && !blacklisted) {
// Ensure the outside world knows about our changes
changePlaylistFn();
}
return enable;
};
/**
* The representation object encapsulates the publicly visible information
* in a media playlist along with a setter/getter-type function (enabled)
* for changing the enabled-state of a particular playlist entry
*
* @class Representation
*/
class Representation {
constructor(hlsHandler, playlist, id) {
// Get a reference to a bound version of fastQualityChange_
let fastChangeFunction = hlsHandler
.masterPlaylistController_
.fastQualityChange_
.bind(hlsHandler.masterPlaylistController_);
// Carefully descend into the playlist's attributes since most
// properties are optional
if (playlist.attributes) {
let attributes = playlist.attributes;
if (attributes.RESOLUTION) {
let resolution = attributes.RESOLUTION;
this.width = resolution.width;
this.height = resolution.height;
}
this.bandwidth = attributes.BANDWIDTH;
}
// The id is simply the ordinality of the media playlist
// within the master playlist
this.id = id;
// Partially-apply the enableFunction to create a playlist-
// specific variant
this.enabled = enableFunction.bind(this,
hlsHandler.playlists,
playlist.uri,
fastChangeFunction);
}
}
/**
* A mixin function that adds the `representations` api to an instance
* of the HlsHandler class
* @param {HlsHandler} hlsHandler - An instance of HlsHandler to add the
* representation API into
*/
let renditionSelectionMixin = function(hlsHandler) {
let playlists = hlsHandler.playlists;
// Add a single API-specific function to the HlsHandler instance
hlsHandler.representations = () => {
return playlists
.master
.playlists
.filter((media) => !isBlacklisted(media))
.map((e, i) => new Representation(hlsHandler, e, e.uri));
};
};
export default renditionSelectionMixin;