Asymmetrik/ngx-starter

import { NgIf } from '@angular/common';
import {
    Directive,
    Injector,
    OnInit,
    booleanAttribute,
    effect,
    inject,
    input
} from '@angular/core';

import { APP_SESSION } from '../../tokens';

@Directive({
    selector: '[isAuthenticated]',
    hostDirectives: [
        {
            directive: NgIf,
            inputs: ['ngIfElse: isAuthenticatedElse', 'ngIfThen: isAuthenticatedThen']
        }
    ],
    standalone: true
})
export class IsAuthenticatedDirective implements OnInit {
    readonly #ngIfDirective = inject(NgIf);
    readonly #injector = inject(Injector);
    readonly #session = inject(APP_SESSION);

    readonly isAuthenticated = input(true, { transform: booleanAttribute });
    readonly andCondition = input(true, { alias: 'isAuthenticatedAnd' });
    readonly orCondition = input(false, { alias: 'isAuthenticatedOr' });

    ngOnInit() {
        effect(
            () => {
                this.updateNgIf();
            },
            { injector: this.#injector }
        );
    }

    private updateNgIf() {
        this.#ngIfDirective.ngIf =
            this.orCondition() || (this.andCondition() && this.#session().isAuthenticated());
    }
}