"use client";

// Lightweight client-side session bridge for the Meshkee customer account.
//
// This storefront has no login form of its own — signing in happens on the
// separate customer portal (CUSTOMER_PORTAL_URL). What's implemented here is
// the "come back logged in" half of that flow:
//
//   1. The customer portal sends the shopper back to this site with
//      `?token=<accessToken>&refreshToken=<refreshToken>` in the URL.
//   2. On first render we pick those up, store them, and strip them from
//      the address bar.
//   3. From then on we call `GET /auth/me` with the stored access token to
//      know who's signed in (and to detect an admin, for "مدیریت وبسایت").
//
// NOTE: the exact hand-back mechanism isn't published in the public API
// docs (auth is plain Bearer-JWT, not a shared cookie), so this is the
// standard "redirect back with tokens in the query string" pattern. If
// Meshkee's customer portal actually bridges sessions a different way
// (shared cookie, postMessage, …), swap the implementation in this file —
// everything that reads auth state goes through the hooks below.

import { useCallback, useEffect, useState } from "react";
import { API_BASE } from "./meshkee";

const ACCESS_TOKEN_KEY = "meshkee_access_token";
const REFRESH_TOKEN_KEY = "meshkee_refresh_token";

export function getStoredAccessToken() {
  if (typeof window === "undefined") return null;
  try {
    return window.localStorage.getItem(ACCESS_TOKEN_KEY);
  } catch {
    return null;
  }
}

function storeTokens({ accessToken, refreshToken }) {
  try {
    if (accessToken) window.localStorage.setItem(ACCESS_TOKEN_KEY, accessToken);
    if (refreshToken) window.localStorage.setItem(REFRESH_TOKEN_KEY, refreshToken);
  } catch {
    /* localStorage unavailable (private mode, etc.) — session just won't persist */
  }
}

export function clearStoredTokens() {
  try {
    window.localStorage.removeItem(ACCESS_TOKEN_KEY);
    window.localStorage.removeItem(REFRESH_TOKEN_KEY);
  } catch {
    /* noop */
  }
}

/** Picks up `?token=&refreshToken=` from a customer-portal hand-back, once. */
function captureTokenFromUrl() {
  const params = new URLSearchParams(window.location.search);
  const token = params.get("token") || params.get("accessToken");
  const refreshToken = params.get("refreshToken");
  if (!token) return false;

  storeTokens({ accessToken: token, refreshToken });
  params.delete("token");
  params.delete("accessToken");
  params.delete("refreshToken");
  const query = params.toString();
  const cleanUrl = window.location.pathname + (query ? `?${query}` : "") + window.location.hash;
  window.history.replaceState({}, "", cleanUrl);
  return true;
}

async function fetchCurrentUser(accessToken) {
  const res = await fetch(`${API_BASE}/auth/me`, {
    headers: { Authorization: `Bearer ${accessToken}` },
  });
  if (!res.ok) return null;
  const data = await res.json().catch(() => null);
  return data?.user ?? data ?? null;
}

/** True when the account object looks like a business admin, not a regular customer. */
export function isAdminUser(user) {
  if (!user) return false;
  const role = String(user.role || user.type || "").toLowerCase();
  return Boolean(user.isAdmin) || role.includes("admin") || role.includes("owner");
}

/**
 * Session state for the header: `{ status: 'loading' | 'guest' | 'in', user, logout }`.
 */
export function useMeshkeeSession() {
  const [state, setState] = useState({ status: "loading", user: null });

  const load = useCallback(async () => {
    captureTokenFromUrl();
    const token = getStoredAccessToken();
    if (!token) {
      setState({ status: "guest", user: null });
      return;
    }
    const user = await fetchCurrentUser(token);
    if (user) {
      setState({ status: "in", user });
    } else {
      clearStoredTokens();
      setState({ status: "guest", user: null });
    }
  }, []);

  useEffect(() => {
    load();
  }, [load]);

  const logout = useCallback(() => {
    clearStoredTokens();
    setState({ status: "guest", user: null });
  }, []);

  return { ...state, logout };
}