Asymmetrik/ngx-starter

import { ViewportScroller } from '@angular/common';
import { APP_INITIALIZER, Provider, makeEnvironmentProviders } from '@angular/core';
import { toSignal } from '@angular/core/rxjs-interop';

import { firstValueFrom } from 'rxjs';
import { tap } from 'rxjs/operators';

import { SessionService } from './auth';
import { ConfigService } from './config.service';
import { CustomViewportScroller, SCROLL_ELEMENT } from './custom_viewport_scroller';
import { NavigationService } from './navigation.service';
import { APP_CONFIG, APP_SESSION } from './tokens';

export function provideAppConfig() {
    return makeEnvironmentProviders([
        {
            provide: APP_INITIALIZER,
            useFactory: (configService: ConfigService) => {
                return () =>
                    firstValueFrom(
                        configService.getConfig().pipe(
                            tap((config) => {
                                if (config === null) {
                                    throw new Error('Error loading application configuration.');
                                }
                            })
                        )
                    );
            },
            deps: [ConfigService],
            multi: true
        },
        {
            provide: APP_CONFIG,
            useFactory: (configService: ConfigService) => {
                return toSignal(configService.getConfig());
            },
            deps: [ConfigService]
        }
    ]);
}

export function provideNavigationService() {
    return makeEnvironmentProviders([
        {
            provide: APP_INITIALIZER,
            useFactory: (navigationService: NavigationService) => {
                return () => {
                    navigationService.init();
                };
            },
            deps: [NavigationService],
            multi: true
        }
    ]);
}

export function provideViewportScroller(scrollElementID?: string) {
    const providers: Provider[] = [
        {
            provide: ViewportScroller,
            useClass: CustomViewportScroller
        }
    ];
    if (scrollElementID) {
        providers.push({
            provide: SCROLL_ELEMENT,
            useValue: scrollElementID
        });
    }

    return makeEnvironmentProviders(providers);
}

export function provideSession() {
    return makeEnvironmentProviders([
        {
            provide: APP_SESSION,
            useFactory: (sessionService: SessionService) => {
                return sessionService.session;
            },
            deps: [SessionService]
        }
    ]);
}