Method connect

libs/state/src/lib/rx-state.service.ts:542–665

* @internal

(
    keyOrInputOrSlice$:
      | Key
      | Observable<Partial<State> | Value>
      | Signal<Partial<State> | Value>,
    projectOrSlices$?:
      | ProjectStateReducer<State, Value>
      | Observable<State[Key] | Value>
      | Signal<State[Key] | Value>,
    projectValueFn?: ProjectValueReducer<State, Key, Value>,
  )

   * @internal
   */
  connect<Key extends keyof State, Value extends Partial<State>>(
    keyOrInputOrSlice$:
      | Key
      | Observable<Partial<State> | Value>
      | Signal<Partial<State> | Value>,
    projectOrSlices$?:
      | ProjectStateReducer<State, Value>
      | Observable<State[Key] | Value>
      | Signal<State[Key] | Value>,
    projectValueFn?: ProjectValueReducer<State, Key, Value>,
  ): void {
    /**
     * From top to bottom the overloads are handled.
     */
    if (
      isObservable(keyOrInputOrSlice$) &&
      !projectOrSlices$ &&
      !projectValueFn
    ) {
      this.accumulator.nextSliceObservable(keyOrInputOrSlice$);
      return;
    }

    if (isSignal(keyOrInputOrSlice$) && !projectOrSlices$ && !projectValueFn) {
      this.accumulator.nextSliceObservable(
        toObservableMicrotaskInternal(keyOrInputOrSlice$, {
          injector: this.injector,
        }),
      );
      return;
    }

    if (
      isObservable(keyOrInputOrSlice$) &&
      projectOrSlices$ &&
      typeof projectOrSlices$ === 'function' &&
      !projectValueFn
    ) {
      const projectionStateFn = projectOrSlices$;
      const slice$ = keyOrInputOrSlice$.pipe(
        map((v) => projectionStateFn(this.accumulator.state, v as Value)),
      );
      this.accumulator.nextSliceObservable(slice$ as Observable<Value>);
      return;
    }

    if (
      isSignal(keyOrInputOrSlice$) &&
      projectOrSlices$ &&
      typeof projectOrSlices$ === 'function' &&
      !projectValueFn
    ) {
      const projectionStateFn = projectOrSlices$;
      const slice$ = toObservableMicrotaskInternal(keyOrInputOrSlice$, {
        injector: this.injector,
      }).pipe(
        map((v) => projectionStateFn(this.accumulator.state, v as Value)),
      );