import { Injectable, TemplateRef, signal } from '@angular/core';

/**
 * Bridges per-page action controls into the shared system header rendered by
 * UserPortalComponent. A child route cannot project content into its parent
 * shell through <router-outlet>, so pages register a TemplateRef here and the
 * shell renders it in the header's right-side actions slot.
 */
@Injectable({ providedIn: 'root' })
export class PageHeaderService {
  /** The current page's action controls, or null when the page has none. */
  readonly actions = signal<TemplateRef<unknown> | null>(null);

  /** Called by a page (typically in ngAfterViewInit) to publish its actions. */
  public setActions(actionsTemplate: TemplateRef<unknown> | null): void {
    this.actions.set(actionsTemplate);
  }

  /** Called by a page in ngOnDestroy so its actions do not leak to the next page. */
  public clear(): void {
    this.actions.set(null);
  }
}