import type { RelatedPerson } from "fhir/r4";
import { splitTeamsByOwner, type TeamWithMembers } from "../../../utils/collaborationTeamSides";

/**
 * The quiet quantity beside three doors. Each number comes from the list its destination page reads,
 * and stays undefined until that list has answered: no number is better than a wrong zero.
 */
export interface PatientHomeDoorCounts {
  practices?: number;
  family?: number;
  collaboration?: number;
}

export const doorQuantity = (doorId: string, counts: PatientHomeDoorCounts): string | undefined => {
  const count = counts[doorId as keyof PatientHomeDoorCounts];
  // A practice is listed only once the patient has booked and authorized it, so a new patient's true zero sat
  // under the header of the practice whose portal they had just joined. My practices says why; the door waits.
  if (doorId === "practices" && count === 0) return undefined;
  return count === undefined ? undefined : String(count);
};

// Both tabs of Family & caregivers, each deduplicated the way the page lists it: who can access me, and the
// people I help. Unknown until each has answered, so a half-read count never shows.
export const familyCount = (source: {
  patientId: string | undefined;
  answeredFor: string | undefined;
  loading: boolean;
  error: string | undefined;
  relatedPersons: RelatedPerson[];
  helping?: { loading: boolean; error?: unknown; subjects: string[] };
}): number | undefined => {
  const { patientId, answeredFor, loading, error, relatedPersons, helping } = source;
  if (!patientId || answeredFor !== patientId || loading || error) return undefined;
  if (helping && (helping.loading || helping.error)) return undefined;
  return new Set(relatedPersons.map((person) => person.id)).size + new Set(helping?.subjects ?? []).size;
};

// The patient's own teams that are still open; a dissolved team is not counted anywhere.
export const ownTeamCount = (source: {
  patientId: string | undefined;
  openTeams: TeamWithMembers[];
  loading: boolean;
  error: string | null;
}): number | undefined => {
  const { patientId, openTeams, loading, error } = source;
  if (!patientId || loading || error) return undefined;
  return splitTeamsByOwner(openTeams, patientId, []).mine.length;
};