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 { DataBlockComponent } from '@shared/ui/data-block/data-block.component';
import { DataRowComponent } from '@shared/ui/data-row/data-row.component';
import { ASYNC } from '@shared/ui/async/async.component';
import { AccessStore } from '@shared/application/access.store';
import { formatDatumNl } from '@shared/kernel/datum';
import { Aanvraag } from '@registratie/domain/aanvraag';
import { TYPE_LABELS, statusLabel, referentie } from '@registratie/domain/aanvraag-view';
import { AdminCasesStore } from '@registratie/application/admin-cases.store';

/**
 * Admin page: every case across all owners, with an admin delete (WP-36). Lives in
 * `registratie` (which owns the Aanvraag aggregate) — the back-office counterpart of the
 * user's dashboard, reusing the same view labels + trust-boundary parse. Deny-by-default
 * capability gate (`cases:manage`): a denial alert for non-admins, the list for admins.
 * Delete is guarded by a native confirm — it is irreversible and may remove submitted cases.
 */
@Component({
  selector: 'app-admin-cases-page',
  imports: [
    PageShellComponent,
    AlertComponent,
    ButtonComponent,
    DataBlockComponent,
    DataRowComponent,
    ...ASYNC,
  ],
  styles: [
    `
      .case {
        margin-block-end: var(--rhc-space-max-lg);
      }
    `,
  ],
  template: `
    <app-page-shell [heading]="heading" [intro]="intro" backLink="/dashboard">
      @if (!access.ready()) {
        <!-- wait for /me before deciding — avoids flashing the denial to an admin -->
      } @else if (!canManage()) {
        <app-alert type="error">{{ deniedText }}</app-alert>
      } @else {
        <app-async [data]="store.cases()">
          <ng-template appAsyncError>
            <app-alert type="error">{{ failedText }}</app-alert>
            <app-button variant="secondary" (click)="reload()">{{ retryText }}</app-button>
          </ng-template>
          <ng-template appAsyncLoaded>
            @if (cases().length === 0) {
              <app-alert type="info">{{ emptyText }}</app-alert>
            } @else {
              @for (c of cases(); track c.id) {
                <div class="case">
                  <app-data-block [heading]="typeLabel(c)" [level]="2">
                    @for (row of rows(c); track row.key) {
                      <div app-data-row [key]="row.key" [value]="row.value"></div>
                    }
                  </app-data-block>
                  <app-button variant="secondary" (click)="confirmDelete(c)">{{
                    deleteText
                  }}</app-button>
                </div>
              }
            }
          </ng-template>
        </app-async>
      }
    </app-page-shell>
  `,
})
export class AdminCasesPage {
  protected store = inject(AdminCasesStore);
  protected access = inject(AccessStore);

  protected canManage = computed(() => this.access.can('cases:manage'));
  protected cases = computed(() => {
    const rd = this.store.cases();
    return rd.tag === 'Success' ? rd.value : [];
  });

  protected heading = $localize`:@@adminCases.heading:Aanvragen beheren`;
  protected intro = $localize`:@@adminCases.intro:Alle aanvragen in het register. Een aanvraag verwijderen kan niet ongedaan worden gemaakt.`;
  protected deniedText = $localize`:@@adminCases.denied:U hebt geen rechten om aanvragen te beheren.`;
  protected failedText = $localize`:@@adminCases.failed:De aanvragen konden niet worden geladen.`;
  protected emptyText = $localize`:@@adminCases.empty:Er zijn geen aanvragen.`;
  protected retryText = $localize`:@@adminCases.retry:Opnieuw proberen`;
  protected deleteText = $localize`:@@adminCases.delete:Verwijderen`;

  private ownerKey = $localize`:@@adminCases.owner:Eigenaar (BSN)`;
  private statusKey = $localize`:@@adminCases.status:Status`;
  private refKey = $localize`:@@adminCases.referentie:Referentie`;
  private ingediendKey = $localize`:@@adminCases.ingediend:Ingediend op`;

  protected typeLabel = (c: Aanvraag) => TYPE_LABELS[c.type];

  /** Key/value rows for one case (owner + lifecycle facts; the type is the block heading). */
  protected rows(c: Aanvraag): { key: string; value: string }[] {
    return [
      { key: this.ownerKey, value: c.owner ?? '—' },
      { key: this.statusKey, value: statusLabel(c.status) },
      { key: this.refKey, value: referentie(c.status) || '—' },
      { key: this.ingediendKey, value: c.submittedAt ? formatDatumNl(c.submittedAt) : '—' },
    ];
  }

  private loadRequested = false;
  constructor() {
    // Load once the capability resolves to allowed (a 403 GET would be wasted otherwise).
    // Depends only on canManage() + a plain flag — never the store model (WP-26 loop lesson).
    effect(() => {
      if (this.canManage() && !this.loadRequested) {
        this.loadRequested = true;
        void this.store.load();
      }
    });
  }

  protected reload() {
    void this.store.load();
  }

  /** Native confirm — no dialog component exists, and admin delete is irreversible. */
  protected confirmDelete(c: Aanvraag) {
    const msg = $localize`:@@adminCases.confirm:Deze aanvraag definitief verwijderen?`;
    if (confirm(msg)) void this.store.delete(c.id);
  }
}