import { Operator } from '../Operator';
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import { Subscriber } from '../Subscriber';
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import { Observable } from '../Observable';
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import { OuterSubscriber } from '../OuterSubscriber';
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import { InnerSubscriber } from '../InnerSubscriber';
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import { subscribeToResult } from '../util/subscribeToResult';
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import { ObservableInput, OperatorFunction, ObservedValueOf } from '../types';
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/* tslint:disable:max-line-length */
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export function withLatestFrom<T, R>(project: (v1: T) => R): OperatorFunction<T, R>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, R>(source2: O2, project: (v1: T, v2: ObservedValueOf<O2>) => R): OperatorFunction<T, R>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, R>(v2: O2, v3: O3, project: (v1: T, v2: ObservedValueOf<O2>, v3: ObservedValueOf<O3>) => R): OperatorFunction<T, R>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, R>(v2: O2, v3: O3, v4: O4, project: (v1: T, v2: ObservedValueOf<O2>, v3: ObservedValueOf<O3>, v4: ObservedValueOf<O4>) => R): OperatorFunction<T, R>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>, R>(v2: O2, v3: O3, v4: O4, v5: O5, project: (v1: T, v2: ObservedValueOf<O2>, v3: ObservedValueOf<O3>, v4: ObservedValueOf<O4>, v5: ObservedValueOf<O5>) => R): OperatorFunction<T, R>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>, O6 extends ObservableInput<any>, R>(v2: O2, v3: O3, v4: O4, v5: O5, v6: O6, project: (v1: T, v2: ObservedValueOf<O2>, v3: ObservedValueOf<O3>, v4: ObservedValueOf<O4>, v5: ObservedValueOf<O5>, v6: ObservedValueOf<O6>) => R): OperatorFunction<T, R>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>>(source2: O2): OperatorFunction<T, [T, ObservedValueOf<O2>]>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>>(v2: O2, v3: O3): OperatorFunction<T, [T, ObservedValueOf<O2>, ObservedValueOf<O3>]>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>>(v2: O2, v3: O3, v4: O4): OperatorFunction<T, [T, ObservedValueOf<O2>, ObservedValueOf<O3>, ObservedValueOf<O4>]>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>>(v2: O2, v3: O3, v4: O4, v5: O5): OperatorFunction<T, [T, ObservedValueOf<O2>, ObservedValueOf<O3>, ObservedValueOf<O4>, ObservedValueOf<O5>]>;
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export function withLatestFrom<T, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>, O6 extends ObservableInput<any>>(v2: O2, v3: O3, v4: O4, v5: O5, v6: O6): OperatorFunction<T, [T, ObservedValueOf<O2>, ObservedValueOf<O3>, ObservedValueOf<O4>, ObservedValueOf<O5>, ObservedValueOf<O6>]>;
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export function withLatestFrom<T, R>(...observables: Array<ObservableInput<any> | ((...values: Array<any>) => R)>): OperatorFunction<T, R>;
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export function withLatestFrom<T, R>(array: ObservableInput<any>[]): OperatorFunction<T, R>;
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export function withLatestFrom<T, R>(array: ObservableInput<any>[], project: (...values: Array<any>) => R): OperatorFunction<T, R>;
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/* tslint:enable:max-line-length */
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/**
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* Combines the source Observable with other Observables to create an Observable
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* whose values are calculated from the latest values of each, only when the
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* source emits.
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*
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* <span class="informal">Whenever the source Observable emits a value, it
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* computes a formula using that value plus the latest values from other input
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* Observables, then emits the output of that formula.</span>
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*
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* 
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*
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* `withLatestFrom` combines each value from the source Observable (the
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* instance) with the latest values from the other input Observables only when
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* the source emits a value, optionally using a `project` function to determine
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* the value to be emitted on the output Observable. All input Observables must
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* emit at least one value before the output Observable will emit a value.
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*
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* ## Example
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* On every click event, emit an array with the latest timer event plus the click event
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* ```ts
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* import { fromEvent, interval } from 'rxjs';
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* import { withLatestFrom } from 'rxjs/operators';
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*
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* const clicks = fromEvent(document, 'click');
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* const timer = interval(1000);
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* const result = clicks.pipe(withLatestFrom(timer));
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* result.subscribe(x => console.log(x));
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* ```
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*
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* @see {@link combineLatest}
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*
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* @param {ObservableInput} other An input Observable to combine with the source
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* Observable. More than one input Observables may be given as argument.
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* @param {Function} [project] Projection function for combining values
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* together. Receives all values in order of the Observables passed, where the
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* first parameter is a value from the source Observable. (e.g.
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* `a.pipe(withLatestFrom(b, c), map(([a1, b1, c1]) => a1 + b1 + c1))`). If this is not
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* passed, arrays will be emitted on the output Observable.
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* @return {Observable} An Observable of projected values from the most recent
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* values from each input Observable, or an array of the most recent values from
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* each input Observable.
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* @method withLatestFrom
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* @owner Observable
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*/
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export function withLatestFrom<T, R>(...args: Array<ObservableInput<any> | ((...values: Array<any>) => R)>): OperatorFunction<T, R> {
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return (source: Observable<T>) => {
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let project: any;
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if (typeof args[args.length - 1] === 'function') {
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project = args.pop();
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}
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const observables = <Observable<any>[]>args;
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return source.lift(new WithLatestFromOperator(observables, project));
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};
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}
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class WithLatestFromOperator<T, R> implements Operator<T, R> {
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constructor(private observables: Observable<any>[],
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private project?: (...values: any[]) => Observable<R>) {
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}
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call(subscriber: Subscriber<R>, source: any): any {
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return source.subscribe(new WithLatestFromSubscriber(subscriber, this.observables, this.project));
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}
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}
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/**
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* We need this JSDoc comment for affecting ESDoc.
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* @ignore
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* @extends {Ignored}
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*/
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class WithLatestFromSubscriber<T, R> extends OuterSubscriber<T, R> {
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private values: any[];
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private toRespond: number[] = [];
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constructor(destination: Subscriber<R>,
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private observables: Observable<any>[],
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private project?: (...values: any[]) => Observable<R>) {
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super(destination);
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const len = observables.length;
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this.values = new Array(len);
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for (let i = 0; i < len; i++) {
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this.toRespond.push(i);
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}
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for (let i = 0; i < len; i++) {
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let observable = observables[i];
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this.add(subscribeToResult<T, R>(this, observable, undefined, i));
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}
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}
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notifyNext(_outerValue: T, innerValue: R,
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outerIndex: number): void {
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this.values[outerIndex] = innerValue;
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const toRespond = this.toRespond;
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if (toRespond.length > 0) {
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const found = toRespond.indexOf(outerIndex);
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if (found !== -1) {
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toRespond.splice(found, 1);
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}
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}
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}
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notifyComplete() {
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// noop
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}
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protected _next(value: T) {
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if (this.toRespond.length === 0) {
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const args = [value, ...this.values];
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if (this.project) {
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this._tryProject(args);
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} else {
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this.destination.next!(args);
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}
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}
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}
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private _tryProject(args: any[]) {
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let result: any;
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try {
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result = this.project!.apply(this, args);
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} catch (err) {
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this.destination.error!(err);
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return;
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}
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this.destination.next!(result);
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}
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}
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