import { useCallback, useEffect, useRef, useState } from "react";
import { useLocation } from "react-router-dom";
import SetupHelpWidget from "./SetupHelpWidget.tsx";
import { AssistantPanel } from "./AssistantPanel.tsx";
import { assistantSubject, useAssistantConversation } from "./useAssistantConversation.ts";
import { useAuthServiceContext } from "../../services";
import { useSupportTicketRequests, type SupportTicketOutcome, type SupportTicketRequest } from "./supportTicketRequest.ts";

/**
 * Where the setup & help widget meets the app.
 *
 * THE SEAM IS DELIBERATE AND THIN: the container knows nothing about what it holds, and this joins it
 * to the assistant. That boundary is what kept the shell still when the onboarding checklist came out
 * of this surface - the piece that changed was this file and the contract, not the widget.
 *
 * IT USED TO ASSEMBLE THE ONBOARDING CHECKLIST HERE, through `useSetupGuidance`: locations,
 * practitioners, schedules, the public-form count and a resolved task list, so the widget could name an
 * admin's next step and count the rest. The steps live on the overview page, which is the one place
 * that survives - so the assembly went with the checklist, and with it three list fetches that ran
 * behind every screen an admin opened.
 *
 * ONE RENDER FOR EVERY VIEWER, and that is the fix a previous version of this file needed rather than a
 * simplification for its own sake. It used to branch on whether the viewer could reach the setup
 * surface, because the affordance ended in `navigate("/dashboard/organization")` - and a signed-in
 * PATIENT clicked "Setup and help" and landed on their practice's admin screen (observed in a browser
 * 2026-08-19). The server held and nothing was disclosed, but a patient who believes they have seen
 * somebody else's admin screen has been harmed whether or not data crossed. The assistant is a help
 * destination that belongs to everybody, so there is no navigate left to gate and no branch left to
 * take.
 */

// Held above the panel, which unmounts on close, so reopening on the same page keeps the conversation.
export const SetupHelpWidgetMount = () => {
  const conversation = useAssistantConversation(assistantSubject(useLocation()));
  const { currentUser, currentOrganization } = useAuthServiceContext();
  const viewer = currentUser?.fhir?.id;
  const organizationId = currentOrganization?.id;
  const [ticketRequest, setTicketRequest] = useState<SupportTicketRequest | undefined>();
  const [openRequests, setOpenRequests] = useState(0);
  // Who is told what became of the request being held: only the asker of that exact opening.
  const answer = useRef<{ opening: string; tell?: (outcome: SupportTicketOutcome) => void } | undefined>();
  const settle = useCallback((outcome: SupportTicketOutcome, opening?: string) => {
    const waiting = answer.current;
    if (!waiting || (opening !== undefined && waiting.opening !== opening)) return;
    answer.current = undefined;
    setTicketRequest(undefined);
    waiting.tell?.(outcome);
  }, []);

  // A request names the viewer and practice it was made for: another's is refused, and a change of either drops it.
  useEffect(() => {
    answer.current = undefined;
    setTicketRequest(undefined);
  }, [viewer, organizationId]);
  const take = useCallback((request: SupportTicketRequest, tell?: (outcome: SupportTicketOutcome) => void) => {
    if (!viewer || !organizationId || request.viewer !== viewer || request.organizationId !== organizationId) return false;
    // One opening's reference is never replaced by another's before the panel has taken it.
    if (answer.current && answer.current.opening !== request.opening) return false;
    answer.current = { opening: request.opening, tell };
    setTicketRequest((current) => current ?? request);
    setOpenRequests((count) => count + 1);
    return true;
  }, [viewer, organizationId]);
  useSupportTicketRequests(take);

  return (
    <SetupHelpWidget openRequests={openRequests} onOpenRefused={() => settle("refused")}>
      <AssistantPanel
        store={conversation}
        ticketRequest={ticketRequest}
        requestOwner={viewer && organizationId ? `${viewer}|${organizationId}` : undefined}
        onTicketRequestTaken={(outcome, opening) => settle(outcome, opening)}
      />
    </SetupHelpWidget>
  );
};

export default SetupHelpWidgetMount;