import { Component, computed, effect, inject } from '@angular/core';
import { PageShellComponent } from '@shared/layout/page-shell/page-shell.component';
import { AlertComponent } from '@shared/ui/alert/alert.component';
import { ButtonComponent } from '@shared/ui/button/button.component';
import { SkeletonComponent } from '@shared/ui/skeleton/skeleton.component';
import { ASYNC } from '@shared/ui/async/async.component';
import { AccessStore } from '@shared/application/access.store';
import { WerkvoorraadStore } from '@behandeling/application/werkvoorraad.store';
import { WerkvoorraadListComponent } from '@behandeling/ui/werkvoorraad-list/werkvoorraad-list.component';

/**
 * Page: the behandelaar's werkvoorraad (WP-64) — the behandelportal's landing page.
 * Deny-by-default capability gate (`aanvraag:beoordelen`), same idiom as ssp's
 * AdminCasesPage: a denial alert for a non-behandelaar, the queue for one. Opening
 * a case's detail is out of scope here (WP-65).
 */
@Component({
  selector: 'app-werkvoorraad-page',
  imports: [
    PageShellComponent,
    AlertComponent,
    ButtonComponent,
    SkeletonComponent,
    WerkvoorraadListComponent,
    ...ASYNC,
  ],
  template: `
    <app-page-shell [heading]="heading" [intro]="intro">
      @if (!access.ready()) {
        <!-- wait for /me before deciding — avoids flashing the denial to a behandelaar -->
      } @else if (!canBeoordelen()) {
        <app-alert type="error">{{ deniedText }}</app-alert>
      } @else {
        <app-async [data]="store.items()" (retryClicked)="store.reload()">
          <ng-template appAsyncLoading>
            <app-skeleton height="2.5rem" [count]="4" />
          </ng-template>
          <ng-template appAsyncError>
            <app-alert type="error">{{ failedText }}</app-alert>
            <app-button variant="secondary" (click)="store.reload()">{{ retryText }}</app-button>
          </ng-template>
          <ng-template appAsyncLoaded>
            @if (items().length === 0) {
              <app-alert type="info">{{ emptyText }}</app-alert>
            } @else {
              <app-werkvoorraad-list [items]="items()" />
            }
          </ng-template>
        </app-async>
      }
    </app-page-shell>
  `,
})
export class WerkvoorraadPage {
  protected store = inject(WerkvoorraadStore);
  protected access = inject(AccessStore);

  protected canBeoordelen = computed(() => this.access.can('aanvraag:beoordelen'));
  protected items = computed(() => {
    const rd = this.store.items();
    return rd.tag === 'Success' ? rd.value : [];
  });

  protected heading = $localize`:@@werkvoorraad.heading:Werkvoorraad`;
  protected intro = $localize`:@@werkvoorraad.intro:Aanvragen die op beoordeling wachten.`;
  protected deniedText = $localize`:@@werkvoorraad.denied:U hebt geen rechten om de werkvoorraad te bekijken.`;
  protected failedText = $localize`:@@werkvoorraad.failed:De werkvoorraad kon niet worden geladen.`;
  protected emptyText = $localize`:@@werkvoorraad.empty:Er staan geen aanvragen open.`;
  protected retryText = $localize`:@@werkvoorraad.retry:Opnieuw proberen`;

  private loadRequested = false;
  constructor() {
    // Load once the capability resolves to allowed (a 403 GET would be wasted otherwise) —
    // same guard-against-the-loop idiom as AdminCasesPage (WP-26 lesson).
    effect(() => {
      if (this.canBeoordelen() && !this.loadRequested) {
        this.loadRequested = true;
        void this.store.load();
      }
    });
  }
}