// Patient domain types + data access for the temetro chat.
//
// The types below are the canonical record shape (also mirrored by the backend
// at backend/src/types/patient.ts). The data functions call the backend's
// org-scoped patient API; the session cookie is sent automatically by the
// shared fetch wrapper.

import { ApiError, apiFetch } from "@/lib/api-client";

export type AllergySeverity = "mild" | "moderate" | "severe";
export type LabFlag = "normal" | "high" | "low" | "critical";

export type Allergy = {
  substance: string;
  reaction: string;
  severity: AllergySeverity;
};

export type Medication = {
  name: string;
  dose: string;
  frequency: string;
};

export type Problem = {
  label: string;
  since: string;
};

export type Vitals = {
  bp: string;
  hr: string;
  temp: string;
  spo2: string;
  takenAt: string;
};

export type Lab = {
  name: string;
  value: string;
  flag: LabFlag;
  takenAt: string;
};

export type Encounter = {
  date: string;
  type: string;
  provider: string;
  summary: string;
};

// A short series for a sparkline. `points` are most-recent-last, so the
// latest reading is points.at(-1).
export type Trend = {
  label: string;
  unit: string;
  points: number[];
};

export type Patient = {
  fileNumber: string; // MRN / file number, e.g. "10293"
  name: string;
  age: number;
  sex: "M" | "F";
  pcp: string; // primary care provider (display name)
  primaryProviderId?: string | null; // user id of the responsible clinician
  status: "active" | "inpatient" | "discharged";
  initials: string; // for AvatarFallback
  allergies: Allergy[];
  alerts: string[];
  medications: Medication[];
  problems: Problem[];
  vitals: Vitals;
  vitalsTrend: Trend; // headline vital plotted as a sparkline
  labs: Lab[];
  labTrend: Trend; // headline lab plotted as a sparkline
  encounters: Encounter[];
};

// Fetch one patient in the active clinic. Returns null when not found (404).
export async function getPatient(fileNumber: string): Promise<Patient | null> {
  try {
    return await apiFetch<Patient>(
      `/api/patients/${encodeURIComponent(fileNumber.trim())}`,
    );
  } catch (err) {
    if (err instanceof ApiError && err.status === 404) return null;
    throw err;
  }
}

// Every patient in the active clinic.
export async function listPatients(): Promise<Patient[]> {
  return apiFetch<Patient[]>("/api/patients");
}

// Create a new patient. Throws ApiError(409) if the file number is taken.
export async function createPatient(patient: Patient): Promise<Patient> {
  return apiFetch<Patient>("/api/patients", {
    method: "POST",
    body: JSON.stringify(patient),
  });
}

// Replace an existing patient's full record.
export async function updatePatient(patient: Patient): Promise<Patient> {
  return apiFetch<Patient>(
    `/api/patients/${encodeURIComponent(patient.fileNumber)}`,
    {
      method: "PUT",
      body: JSON.stringify(patient),
    },
  );
}

// Reassign a patient to another clinician (sets their primary provider + PCP).
export async function transferPatient(
  fileNumber: string,
  providerId: string,
): Promise<Patient> {
  return apiFetch<Patient>(
    `/api/patients/${encodeURIComponent(fileNumber)}/transfer`,
    {
      method: "POST",
      body: JSON.stringify({ providerId }),
    },
  );
}

// Suggest a unique-ish 5-digit file number for new charts. The server is the
// source of truth and rejects collisions with a 409.
export function generateFileNumber(): string {
  return String(10000 + Math.floor(Math.random() * 89999));
}
