*/

import {Compiler, InjectFlags, InjectionToken, Injector, NgModuleFactory, NgModuleFactoryLoader} from '@angular/core';

import {from, Observable, of} from 'rxjs';

import {map, mergeMap} from 'rxjs/operators';

import {ConnectableObservable, from, Observable, of, Subject} from 'rxjs';

import {catchError, map, mergeMap, refCount, tap} from 'rxjs/operators';

import {LoadChildren, LoadedRouterConfig, Route} from './config';

import {flatten, wrapIntoObservable} from './utils/collection';

private onLoadEndListener?: (r: Route) => void) {}

load(parentInjector: Injector, route: Route): Observable<LoadedRouterConfig> {

if (route._loader$) {

return route._loader$;

}

if (this.onLoadStartListener) {

this.onLoadStartListener(route);

}

const moduleFactory$ = this.loadModuleFactory(route.loadChildren!);

return moduleFactory$.pipe(map((factory: NgModuleFactory<any>) => {

if (this.onLoadEndListener) {

this.onLoadEndListener(route);

}

const module = factory.create(parentInjector);

// When loading a module that doesn't provide `RouterModule.forChild()` preloader will get

// stuck in an infinite loop. The child module's Injector will look to its parent `Injector`

// when it doesn't find any ROUTES so it will return routes for it's parent module instead.

return new LoadedRouterConfig(

flatten(module.injector.get(ROUTES, undefined, InjectFlags.Self | InjectFlags.Optional))

.map(standardizeConfig),

module);

}));

const loadRunner = moduleFactory$.pipe(

map((factory: NgModuleFactory<any>) => {

if (this.onLoadEndListener) {

this.onLoadEndListener(route);

}

const module = factory.create(parentInjector);

// When loading a module that doesn't provide `RouterModule.forChild()` preloader

// will get stuck in an infinite loop. The child module's Injector will look to

// its parent `Injector` when it doesn't find any ROUTES so it will return routes

// for it's parent module instead.

return new LoadedRouterConfig(

flatten(

module.injector.get(ROUTES, undefined, InjectFlags.Self | InjectFlags.Optional))

.map(standardizeConfig),

module);

}),

catchError((err) => {

route._loader$ = undefined;

throw err;

}),

);

// Use custom ConnectableObservable as share in runners pipe increasing the bundle size too much

route._loader$ = new ConnectableObservable(loadRunner, () => new Subject<LoadedRouterConfig>())

.pipe(refCount());

return route._loader$;

}

private loadModuleFactory(loadChildren: LoadChildren): Observable<NgModuleFactory<any>> {