/**
* @license
* Copyright 2016 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
goog.provide('shaka.util.IDestroyable');
/**
* An interface to standardize how objects are destroyed.
* @interface
* @exportInterface
*/
shaka.util.IDestroyable = function() {};
/**
* Destroys the object, releasing all resources and shutting down all
* operations. Returns a Promise which is resolved when destruction is
* complete. This Promise should never be rejected.
*
* @return {!Promise}
* @exportInterface
*/
shaka.util.IDestroyable.prototype.destroy = function() {};
/**
* A helper function that will destroy a group of destroyable object once the
* callback (and its promises) complete. The destroyable object will be
* destroyed regardless of whether or not the callback (and its promises) get
* resolved or rejected.
*
* @param {!Array.<!shaka.util.IDestroyable>} objs A list of destroyable object
* that should be destroyed
* after the callback completes.
* @param {function():!Promise<T>|function():T} callback
* @return {!Promise.<T>}
* @template T
*/
shaka.util.IDestroyable.with = function(objs, callback) {
let cleanup = () => {
return Promise.all(objs.map((obj) => obj.destroy()));
};
return Promise.resolve(callback()).then(
(r) => cleanup().then(() => r),
(e) => cleanup().then(() => { throw e; }));
};