const BASE = "/api";
let token = "";

// Current user info populated after auth
export let currentUser = { username: "", role: "", pages: [] };

export function setCurrentUser(u) {
  currentUser = u;
}

export function setToken(t) {
  token = t;
  if (t) localStorage.setItem("token", t);
  else localStorage.removeItem("token");
}

export function getToken() {
  return token;
}

// Refresh token is cookie-managed server-side.
export function setRefreshToken() {}

let refreshPromise = null;

function getLegacyRefreshToken() {
  return localStorage.getItem("refresh_token") || "";
}

function clearLegacyRefreshToken() {
  localStorage.removeItem("refresh_token");
}

async function requestRefresh(body) {
  const r = await fetch(BASE + "/auth/refresh", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    credentials: "same-origin",
    body: body ? JSON.stringify(body) : undefined,
  });
  if (!r.ok) return false;
  const data = await r.json();
  setToken(data.access_token || "");
  return !!data.access_token;
}

export async function tryRefreshSession() {
  if (refreshPromise) return refreshPromise;
  refreshPromise = (async () => {
    try {
      const cookieRefreshed = await requestRefresh();
      if (cookieRefreshed) {
        clearLegacyRefreshToken();
        return true;
      }

      const legacyRefreshToken = getLegacyRefreshToken();
      if (!legacyRefreshToken) return false;
      const legacyRefreshed = await requestRefresh({ refresh_token: legacyRefreshToken });
      if (legacyRefreshed) {
        clearLegacyRefreshToken();
        return true;
      }
      clearLegacyRefreshToken();
      return false;
    } catch {
      return false;
    } finally {
      refreshPromise = null;
    }
  })();
  return refreshPromise;
}

async function request(path, opts = {}) {
  const headers = opts.headers || {};
  if (token) headers["Authorization"] = `Bearer ${token}`;

  if (opts.json) {
    headers["Content-Type"] = "application/json";
    opts.body = JSON.stringify(opts.json);
    delete opts.json;
  }

  const fetchOpts = { ...opts, headers };
  if (path.startsWith("/auth/")) fetchOpts.credentials = "same-origin";

  try {
    let r = await fetch(BASE + path, fetchOpts);

    if (r.status === 401 && !path.includes("/auth/refresh")) {
      const refreshed = await tryRefreshSession();
      if (refreshed) {
        headers["Authorization"] = `Bearer ${token}`;
        r = await fetch(BASE + path, fetchOpts);
      }
    }

    if (r.status === 401) {
      setToken("");
      throw new Error("Unauthorized");
    }

    if (!r.ok) {
      const error = new Error(`HTTP ${r.status}`);
      error.status = r.status;
      try { error.body = await r.json(); } catch {}
      throw error;
    }
    return r.json();
  } catch (e) {
    console.error(`API ${opts.method || "GET"} ${path}:`, e);
    throw e;
  }
}

export function get(path) {
  return request(path);
}

export function post(path, data) {
  return request(path, { method: "POST", json: data });
}

export function del(path) {
  return request(path, { method: "DELETE" });
}

export async function upload(path, file) {
  const headers = {};
  if (token) headers["Authorization"] = `Bearer ${token}`;

  const form = new FormData();
  form.append("file", file);

  const r = await fetch(`${BASE}/files/upload?path=${encodeURIComponent(path)}`, {
    method: "POST",
    headers,
    body: form,
  });

  if (!r.ok) throw new Error(`HTTP ${r.status}`);
  return r.json();
}

export function login(creds) {
  return request("/auth/login", { method: "POST", json: creds });
}

export function checkAuth() {
  return request("/auth/me");
}

export function logout() {
  return request("/auth/logout", { method: "POST" });
}

export function getPreferences() {
  return get("/auth/preferences");
}

export function savePreferences(data) {
  return request("/auth/preferences", { method: "PUT", json: data });
}

export function getLiteLLMHealth() {
  return get("/litellm/health");
}

export function getCcConnectHealth() {
  return get("/cc-connect/health");
}

export function startCcConnect() {
  return post("/cc-connect/start");
}

export function stopCcConnect() {
  return post("/cc-connect/stop");
}

export function getInfoEngineItems(params = {}) {
  const query = new URLSearchParams();
  if (params.limit !== undefined) query.set("limit", String(params.limit));
  if (params.offset !== undefined) query.set("offset", String(params.offset));
  if (params.source) query.set("source", params.source);
  if (params.tag) query.set("tag", params.tag);
  if (params.since) query.set("since", params.since);
  const suffix = query.toString() ? `?${query.toString()}` : "";
  return get(`/info-engine/items${suffix}`);
}

export function getInfoEngineItem(id) {
  return get(`/info-engine/items/${id}`);
}

export function put(path, data) {
  return request(path, { method: "PUT", json: data });
}