import { Component, computed, inject, input, signal } from '@angular/core';
import { I18nService } from '@core/i18n.service';
import { DialogsService, type ChmodRequest } from '@core/dialogs.service';
import { FocusService } from '@core/focus.service';

const ROLES = ['roleOwner', 'roleGroup', 'roleOthers'] as const;
const PERMS = ['r', 'w', 'x'] as const;

@Component({
  selector: 'app-chmod-dialog',
  template: `
    <div class="fixed inset-0 z-40 grid place-items-center bg-black/40" (mousedown)="cancel()">
      <div
        class="w-80 border border-border bg-card p-4 text-card-foreground shadow-xl"
        (mousedown)="$event.stopPropagation()"
        (keydown.escape)="cancel()"
      >
        <h2 class="text-sm font-semibold">{{ i18n.t('dialogs.chmodTitle') }}</h2>
        <p class="mt-1 truncate text-xs text-muted-foreground">{{ targetLabel() }}</p>

        <table class="mt-3 w-full text-xs">
          <thead>
            <tr class="text-muted-foreground">
              <th class="pb-1 text-left font-normal"></th>
              <th class="pb-1 font-normal">{{ i18n.t('dialogs.read') }}</th>
              <th class="pb-1 font-normal">{{ i18n.t('dialogs.write') }}</th>
              <th class="pb-1 font-normal">{{ i18n.t('dialogs.execute') }}</th>
            </tr>
          </thead>
          <tbody>
            @for (role of roles; track role; let r = $index) {
              <tr>
                <td class="py-1 pr-2 text-muted-foreground">{{ i18n.t('dialogs.' + role) }}</td>
                @for (perm of perms; track perm; let p = $index) {
                  <td class="py-1 text-center">
                    <input
                      type="checkbox"
                      [checked]="hasBit(r, p)"
                      (change)="toggleBit(r, p)"
                      class="size-3.5"
                    />
                  </td>
                }
              </tr>
            }
          </tbody>
        </table>

        <div class="mt-3 flex items-center gap-2">
          <label class="text-xs text-muted-foreground">{{ i18n.t('dialogs.octal') }}</label>
          <input
            [value]="octal()"
            (input)="setOctal($any($event.target).value)"
            maxlength="4"
            spellcheck="false"
            class="h-7 w-20 border border-input bg-transparent px-2 font-mono text-xs outline-none focus:ring-2 focus:ring-ring"
          />
        </div>

        <div class="mt-4 flex justify-end gap-2">
          <button
            (click)="cancel()"
            class="px-3 py-1.5 text-xs font-medium hover:bg-accent"
          >
            {{ i18n.t('common.cancel') }}
          </button>
          <button
            (click)="submit()"
            class="bg-primary px-3 py-1.5 text-xs font-medium text-primary-foreground hover:bg-primary/90"
          >
            {{ i18n.t('common.apply') }}
          </button>
        </div>
      </div>
    </div>
  `,
})
export class ChmodDialog {
  readonly i18n = inject(I18nService);
  readonly request = input.required<ChmodRequest>();

  readonly roles = ROLES;
  readonly perms = PERMS;

  private readonly dialogs = inject(DialogsService);
  private readonly focus = inject(FocusService);

  // mode is initialized lazily from the request on first read
  private readonly modeOverride = signal<number | null>(null);
  readonly mode = computed(() => this.modeOverride() ?? this.request().initialMode & 0o777);
  readonly octal = computed(() => this.mode().toString(8).padStart(3, '0'));

  targetLabel(): string {
    const targets = this.request().targets;
    return targets.length === 1
      ? targets[0]
      : this.i18n.t('dialogs.chmodItems', { count: targets.length });
  }

  hasBit(role: number, perm: number): boolean {
    return !!(this.mode() & (0o400 >> (role * 3 + perm)));
  }

  toggleBit(role: number, perm: number): void {
    this.modeOverride.set(this.mode() ^ (0o400 >> (role * 3 + perm)));
  }

  setOctal(text: string): void {
    if (/^[0-7]{1,4}$/.test(text)) {
      this.modeOverride.set(parseInt(text, 8) & 0o777);
    }
  }

  submit(): void {
    const req = this.request();
    const mode = this.mode();
    this.close();
    req.onConfirm(mode);
  }

  cancel(): void {
    this.close();
  }

  private close(): void {
    this.dialogs.chmod.set(null);
    this.focus.bump();
  }
}