// Admin domain — TanStack Query hooks + query keys (the only public surface).
// State-transition mutations invalidate the proposals/lineItems domain keys
// (rule 3 — cross-domain invalidation via the sibling key objects) and carry
// the same toasts the AdminWorkspace page shows today. Page-specific side
// effects (dialog close, dirty reset, window.open, navigate) stay at the
// call site via the mutation's callbacks.
import { useMutation, useQuery, useQueryClient, type QueryClient } from '@tanstack/react-query';
import { toast } from 'react-toastify';
import { adminApi } from './api';
import { lineItemsApi } from '../lineItems/api';
import { proposalsKeys } from '../proposals/use-cases';
import { lineItemsKeys } from '../lineItems/use-cases';
import type { UpdateLineItemEntry } from '../lineItems/types';

export const adminKeys = {
  all: ['admin'] as const,
  dashboard: () => [...adminKeys.all, 'dashboard'] as const,
  similar: (proposalId: string) => [...adminKeys.all, 'similar', proposalId] as const,
};

/**
 * Every state transition must refresh every view of the proposal: the
 * workspace (detail + line items) AND the cached queue/list/stats/KPI
 * queries — lists sit under the global 5-minute staleTime, so without the
 * broad invalidation an admin returning to the queue after approving sees
 * stale statuses.
 */
function invalidateProposalViews(queryClient: QueryClient, proposalId: string) {
  queryClient.invalidateQueries({ queryKey: proposalsKeys.detail(proposalId) });
  queryClient.invalidateQueries({ queryKey: lineItemsKeys.byProposal(proposalId) });
  queryClient.invalidateQueries({ queryKey: proposalsKeys.lists() });
  queryClient.invalidateQueries({ queryKey: proposalsKeys.stats() });
  queryClient.invalidateQueries({ queryKey: adminKeys.dashboard() });
}

/** Admin dashboard KPIs (AdminDashboard). */
export function useAdminDashboard() {
  return useQuery({
    queryKey: adminKeys.dashboard(),
    queryFn: adminApi.getDashboard,
  });
}

/** RAG similarity results (AdminWorkspace, SimilarProposalsPanel). */
export function useSimilarProposals(proposalId: string | undefined) {
  return useQuery({
    queryKey: adminKeys.similar(proposalId ?? ''),
    queryFn: () => adminApi.getSimilar(proposalId!),
    enabled: !!proposalId,
  });
}

export interface SaveWorkspaceVariables {
  refinedScope: string;
  lineItems: UpdateLineItemEntry[];
}

/**
 * The workspace "Save" action: persist the refined scope, then replace the
 * proposal's line items (mirrors AdminWorkspace saveMutation exactly).
 */
export function useSaveProposalWorkspace(proposalId: string) {
  const queryClient = useQueryClient();
  return useMutation({
    mutationFn: async ({ refinedScope, lineItems }: SaveWorkspaceVariables) => {
      await adminApi.updateProposal(proposalId, { refinedScope });
      await lineItemsApi.bulkUpdate(proposalId, lineItems);
    },
    onSuccess: () => {
      invalidateProposalViews(queryClient, proposalId);
      toast.success('Changes saved');
    },
    onError: (error: Error) => {
      toast.error(`Save failed: ${error.message}`);
    },
  });
}

export function useApproveProposal(proposalId: string) {
  const queryClient = useQueryClient();
  return useMutation({
    mutationFn: () => adminApi.approveProposal(proposalId),
    onSuccess: () => {
      invalidateProposalViews(queryClient, proposalId);
      toast.success('Proposal approved');
    },
    onError: (error: Error) => {
      toast.error(`Approval failed: ${error.message}`);
    },
  });
}

export function useSendProposal(proposalId: string) {
  const queryClient = useQueryClient();
  return useMutation({
    mutationFn: () => adminApi.sendProposal(proposalId),
    onSuccess: () => {
      invalidateProposalViews(queryClient, proposalId);
      toast.success('Proposal marked as sent');
    },
    // Fix: WEB-H5 — mutation must surface failures to the user (relocated
    // from AdminWorkspace during the domain-layer refactor)
    onError: (error: Error) => {
      toast.error(`Send failed: ${error.message}`);
    },
  });
}

export function useReviseProposal(proposalId: string) {
  const queryClient = useQueryClient();
  return useMutation({
    mutationFn: () => adminApi.reviseProposal(proposalId),
    onSuccess: () => {
      invalidateProposalViews(queryClient, proposalId);
      toast.success('Revision created');
    },
    // Fix: WEB-H6 — mutation must surface failures to the user (relocated
    // from AdminWorkspace during the domain-layer refactor)
    onError: (error: Error) => {
      toast.error(`Revision failed: ${error.message}`);
    },
  });
}

export function useReturnToReview(proposalId: string) {
  const queryClient = useQueryClient();
  return useMutation({
    mutationFn: () => adminApi.returnToReview(proposalId),
    onSuccess: () => {
      invalidateProposalViews(queryClient, proposalId);
      toast.success('Proposal returned to review');
    },
    onError: (error: Error) => {
      toast.error(`Return to review failed: ${error.message}`);
    },
  });
}

export function useGenerateSuggestions(proposalId: string) {
  return useMutation({
    mutationFn: () => adminApi.generateSuggestions(proposalId),
    onSuccess: () => {
      toast.info('AI suggestion generation started');
    },
    onError: (error: Error) => {
      toast.error(`Regeneration failed: ${error.message}`);
    },
  });
}

/**
 * Fetch (or queue generation of) the branded PDF. Resolves null while
 * generation is queued (202). Success handling — open the download and
 * toast — is page behavior and belongs at the call site.
 */
export function useProposalPdf(proposalId: string) {
  return useMutation({
    mutationFn: (regenerate?: boolean) => adminApi.getPdf(proposalId, regenerate ?? false),
    onError: () => {
      toast.error('Failed to generate PDF');
    },
  });
}