import { Directive, Input, TemplateRef, ViewContainerRef, OnInit, AfterViewInit } from '@angular/core';
import { FeatureService } from '../services/feature.service';

/**
 * Add the template content to the DOM when feature is enabled
 * Usage:
 *  <div *feature="'exampleFeature'"></div>
 */
@Directive({ selector: '[feature]' })
export class FeatureDirective implements OnInit {
  @Input() feature: string;
  constructor(
    private templateRef: TemplateRef<any>,
    private viewContainer: ViewContainerRef,
    private featureService: FeatureService,
  ) {}

  ngOnInit() {
    this.featureService.changes().subscribe((features: any) => {
      if (this.featureService.hasFeature(this.feature)) {
        this.viewContainer.createEmbeddedView(this.templateRef);
      } else {
        this.viewContainer.clear();
      }
    });
  }
}