/**
 * useCrawledPages Hook
 *
 * TanStack Query hook for fetching discovered pages (crawled pages) for a tenant.
 * Provides automatic caching, request deduplication, and background refetching.
 *
 * @layer Presentation
 */

import { useQuery } from '@tanstack/react-query';
import { queryKeys } from '@/lib/query-keys';
import { infoCenterApi } from '@/infrastructure/http/api/info-center';
import type { DiscoveredPage } from '@/domain/entities/DiscoveredPage';

/**
 * useCrawledPages Hook Options
 */
export interface UseCrawledPagesOptions {
  /**
   * Tenant ID to fetch pages for
   */
  tenantId?: string;

  /**
   * Page number (1-indexed)
   * @default 1
   */
  page?: number;

  /**
   * Number of items per page
   * @default 50
   */
  limit?: number;

  /**
   * Enable/disable the query
   * @default true (when tenantId is provided)
   */
  enabled?: boolean;
}

/**
 * useCrawledPages Hook Return Type
 */
export interface UseCrawledPagesReturn {
  /**
   * Discovered pages array
   */
  pages: DiscoveredPage[];

  /**
   * Loading state
   */
  isLoading: boolean;

  /**
   * Error state
   */
  error: Error | null;

  /**
   * Total count of pages
   */
  total: number;

  /**
   * Total number of pages
   */
  totalPages: number;

  /**
   * Current page number
   */
  page: number;

  /**
   * Items per page
   */
  limit: number;

  /**
   * Has next page
   */
  hasNext: boolean;

  /**
   * Has previous page
   */
  hasPrevious: boolean;

  /**
   * Refetch function
   */
  refetch: () => void;
}

/**
 * Fetch discovered pages for a tenant
 *
 * Uses TanStack Query for automatic caching, request deduplication,
 * and background refetching.
 *
 * @param options - Query options
 * @returns Discovered pages with loading/error states
 *
 * @example
 * ```tsx
 * function PagesList() {
 *   const { pages, isLoading, error, page, totalPages } = useCrawledPages({
 *     tenantId: 'tenant-123',
 *     page: 1,
 *     limit: 50,
 *   });
 *
 *   if (isLoading) return <Spinner />;
 *   if (error) return <Error message={error.message} />;
 *
 *   return (
 *     <div>
 *       <ul>
 *         {pages.map(page => (
 *           <li key={page.id}>{page.url}</li>
 *         ))}
 *       </ul>
 *       <Pagination page={page} totalPages={totalPages} />
 *     </div>
 *   );
 * }
 * ```
 */
export function useCrawledPages(options: UseCrawledPagesOptions = {}): UseCrawledPagesReturn {
  const { tenantId, page = 1, limit = 50, enabled } = options;

  // Query
  const query = useQuery({
    queryKey: queryKeys.infoCenter.pages(tenantId ?? '', { page, limit }),
    queryFn: async () => {
      if (!tenantId) {
        throw new Error('tenantId is required');
      }

      const result = await infoCenterApi.listPages(tenantId, { page, limit });
      return result;
    },
    enabled: enabled !== undefined ? enabled : !!tenantId,
    staleTime: 5 * 60 * 1000, // 5 minutes
    gcTime: 10 * 60 * 1000, // 10 minutes
  });

  const pagination = query.data?.pagination ?? { total: 0, page: 1, limit: 50, totalPages: 0 };

  return {
    pages: query.data?.pages ?? [],
    isLoading: query.isLoading,
    error: query.error as Error | null,
    total: pagination.total,
    totalPages: pagination.totalPages,
    page: pagination.page,
    limit: pagination.limit,
    hasNext: pagination.page < pagination.totalPages,
    hasPrevious: pagination.page > 1,
    refetch: query.refetch,
  };
}