/**
 * @internalapi
 * @module vanilla
 */
/** */
import { isArray, isObject } from '../common/index';
/**
 * An angular1-like promise api
 *
 * This object implements four methods similar to the
 * [angular 1 promise api](https://docs.angularjs.org/api/ng/service/$q)
 *
 * UI-Router evolved from an angular 1 library to a framework agnostic library.
 * However, some of the `@uirouter/core` code uses these ng1 style APIs to support ng1 style dependency injection.
 *
 * This API provides native ES6 promise support wrapped as a $q-like API.
 * Internally, UI-Router uses this $q object to perform promise operations.
 * The `angular-ui-router` (ui-router for angular 1) uses the $q API provided by angular.
 *
 * $q-like promise api
 */
export var $q = {
    /** Normalizes a value as a promise */
    when: function (val) { return new Promise(function (resolve, reject) { return resolve(val); }); },
    /** Normalizes a value as a promise rejection */
    reject: function (val) { return new Promise(function (resolve, reject) { reject(val); }); },
    /** @returns a deferred object, which has `resolve` and `reject` functions */
    defer: function () {
        var deferred = {};
        deferred.promise = new Promise(function (resolve, reject) {
            deferred.resolve = resolve;
            deferred.reject = reject;
        });
        return deferred;
    },
    /** Like Promise.all(), but also supports object key/promise notation like $q */
    all: function (promises) {
        if (isArray(promises)) {
            return Promise.all(promises);
        }
        if (isObject(promises)) {
            // Convert promises map to promises array.
            // When each promise resolves, map it to a tuple { key: key, val: val }
            var chain = Object.keys(promises)
                .map(function (key) { return promises[key].then(function (val) { return ({ key: key, val: val }); }); });
            // Then wait for all promises to resolve, and convert them back to an object
            return $q.all(chain).then(function (values) {
                return values.reduce(function (acc, tuple) { acc[tuple.key] = tuple.val; return acc; }, {});
            });
        }
    },
};
//# sourceMappingURL=q.js.map