import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
import { adminFetch } from './admin-api';

export interface OpenSearchStatus {
  reachable: boolean;
  clusterHealth: string;
  version: string;
  nodeCount: number;
  host: string;
}

export interface PipelineStats {
  queueDepth: number;
  maxQueueSize: number;
  indexedCount: number;
  failedCount: number;
  debounceMs: number;
  indexingRate: number;
  lastIndexedAt: string | null;
}

export interface IndexInfo {
  name: string;
  health: string;
  docCount: number;
  size: string;
  sizeBytes: number;
  primaryShards: number;
  replicaShards: number;
}

export interface IndicesPageResponse {
  indices: IndexInfo[];
  totalIndices: number;
  totalDocs: number;
  totalSize: string;
  page: number;
  pageSize: number;
  totalPages: number;
}

export interface PerformanceStats {
  queryCacheHitRate: number;
  requestCacheHitRate: number;
  searchLatencyMs: number;
  indexingLatencyMs: number;
  jvmHeapUsedBytes: number;
  jvmHeapMaxBytes: number;
}

export interface IndicesParams {
  search?: string;
  page?: number;
  size?: number;
}

export function useOpenSearchStatus() {
  return useQuery({
    queryKey: ['admin', 'opensearch', 'status'],
    queryFn: () => adminFetch<OpenSearchStatus>('/opensearch/status'),
  });
}

export function usePipelineStats() {
  return useQuery({
    queryKey: ['admin', 'opensearch', 'pipeline'],
    queryFn: () => adminFetch<PipelineStats>('/opensearch/pipeline'),
    refetchInterval: 15000,
  });
}

export function useIndices(params: IndicesParams) {
  const query = new URLSearchParams();
  if (params.search) query.set('search', params.search);
  if (params.page !== undefined) query.set('page', String(params.page));
  if (params.size !== undefined) query.set('size', String(params.size));
  const qs = query.toString();

  return useQuery({
    queryKey: ['admin', 'opensearch', 'indices', params],
    queryFn: () =>
      adminFetch<IndicesPageResponse>(
        `/opensearch/indices${qs ? `?${qs}` : ''}`,
      ),
  });
}

export function usePerformanceStats() {
  return useQuery({
    queryKey: ['admin', 'opensearch', 'performance'],
    queryFn: () => adminFetch<PerformanceStats>('/opensearch/performance'),
    refetchInterval: 15000,
  });
}

export function useDeleteIndex() {
  const qc = useQueryClient();
  return useMutation({
    mutationFn: async (indexName: string) => {
      await adminFetch<void>(`/opensearch/indices/${encodeURIComponent(indexName)}`, {
        method: 'DELETE',
      });
    },
    onSuccess: () => qc.invalidateQueries({ queryKey: ['admin', 'opensearch', 'indices'] }),
  });
}