import axios from "axios";

import { API_BASE_URL } from "@/constants/apiConfig";
import {
  AUTH_TOKEN_COOKIE,
  REFRESH_TOKEN_COOKIE,
  clearSessionCookies,
  getCookie,
  setCookie,
} from "./cookies";
import type { AuthTokens } from "./types";

type RetriableRequest = {
  _retry?: boolean;
  headers?: Record<string, string>;
  url?: string;
};

const api = axios.create({
  baseURL: `${API_BASE_URL}/api`,
  withCredentials: true,
});

let refreshPromise: Promise<AuthTokens> | null = null;

const applyTokens = ({ token, refreshToken }: AuthTokens) => {
  setCookie(AUTH_TOKEN_COOKIE, token);
  setCookie(REFRESH_TOKEN_COOKIE, refreshToken);
};

api.interceptors.request.use((config) => {
  const token = getCookie(AUTH_TOKEN_COOKIE);

  if (token) {
    config.headers.Authorization = `Bearer ${token}`;
  }

  return config;
});

api.interceptors.response.use(
  (response) => {
    if (
      response.data &&
      typeof response.data === "object" &&
      "success" in response.data &&
      "data" in response.data
    ) {
      response.data = response.data.data;
    }

    return response;
  },
  async (error) => {
    const originalRequest = error.config as RetriableRequest | undefined;

    if (
      error.response?.status !== 401 ||
      !originalRequest ||
      originalRequest._retry ||
      originalRequest.url?.includes("/auth/login") ||
      originalRequest.url?.includes("/auth/mfa-verify") ||
      originalRequest.url?.includes("/auth/refresh-token")
    ) {
      return Promise.reject(error);
    }

    const refreshToken = getCookie(REFRESH_TOKEN_COOKIE);
    if (!refreshToken) {
      clearSessionCookies();
      return Promise.reject(error);
    }

    originalRequest._retry = true;

    try {
      refreshPromise ??= api
        .post<AuthTokens>("/auth/refresh-token", { refreshToken })
        .then((response) => response.data)
        .finally(() => {
          refreshPromise = null;
        });

      const tokens = await refreshPromise;
      applyTokens(tokens);
      originalRequest.headers = {
        ...originalRequest.headers,
        Authorization: `Bearer ${tokens.token}`,
      };

      return api(originalRequest);
    } catch (refreshError) {
      clearSessionCookies();
      window.location.replace("/auth");
      return Promise.reject(refreshError);
    }
  },
);

export { api, applyTokens };
