import axios, { type InternalAxiosRequestConfig } from "axios";
import { authBridge } from "./auth-bridge";
import { getClientCookie } from "./cookies";
import { isLocale } from "../translations/config";

const PROXY_PATH_PARAM = "__proxyPath";
const LOCALHOST_HOSTNAMES = new Set(["localhost", "127.0.0.1", "::1"]);

function isAbsoluteUrl(url: string) {
  return /^[a-z][a-z\d+\-.]*:\/\//i.test(url);
}

function shouldUseProxy() {
  if (process.env.NEXT_PUBLIC_DISABLE_PROXY === "true") {
    return false;
  }

  if (typeof window === "undefined") {
    return false;
  }

  return true;
}

function withProxyPathParam(
  params: InternalAxiosRequestConfig["params"],
  proxyPath: string,
) {
  if (params instanceof URLSearchParams) {
    const nextParams = new URLSearchParams(params);
    nextParams.set(PROXY_PATH_PARAM, proxyPath);
    return nextParams;
  }

  if (typeof params === "string") {
    const nextParams = new URLSearchParams(params);
    nextParams.set(PROXY_PATH_PARAM, proxyPath);
    return nextParams;
  }

  return {
    ...(params && typeof params === "object" ? params : {}),
    [PROXY_PATH_PARAM]: proxyPath,
  };
}

export function getApiRequestUrl(path: string) {
  if (!isAbsoluteUrl(path) && shouldUseProxy()) {
    const searchParams = new URLSearchParams({
      [PROXY_PATH_PARAM]: path,
    });

    return `/api/proxy?${searchParams.toString()}`;
  }

  return `${process.env.NEXT_PUBLIC_API_BASE_URL}${path}`;
}

export const http = axios.create({
  baseURL: shouldUseProxy()
    ? "/api/proxy"
    : process.env.NEXT_PUBLIC_API_BASE_URL,
  headers: {
    Accept: "application/json",
    "Content-Type": "application/json",
  },
  withCredentials: true,
});

http.interceptors.request.use((config) => {
  if (shouldUseProxy() && config.url && !isAbsoluteUrl(config.url)) {
    config.params = withProxyPathParam(config.params, config.url);
    config.url = "";
  }

  // Cache-busting: add timestamp to GET requests so browser never serves stale data
  if (!config.method || config.method.toLowerCase() === "get") {
    config.params = {
      ...(config.params && typeof config.params === "object"
        ? config.params
        : {}),
      _t: Date.now(),
    };
  }

  // Tell browser not to cache API responses
  config.headers["Cache-Control"] = "no-cache, no-store, must-revalidate";
  config.headers["Pragma"] = "no-cache";

  const stripNoToken = (v: string | null) =>
    v && v !== "NO_TOKEN" ? v : null;

  const token =
    authBridge.getToken() ??
    stripNoToken(getClientCookie("HABIB_TOKEN")) ??
    stripNoToken(getClientCookie("habib_token"));

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

  let lang: string | undefined =
    getClientCookie("HABIB_LANGUAGE") ??
    getClientCookie("habib_language") ??
    undefined;
  if (!isLocale(lang)) {
    const pathSegment =
      typeof window !== "undefined"
        ? window.location.pathname.split("/")[1]
        : undefined;
    if (isLocale(pathSegment)) {
      lang = pathSegment;
    } else {
      const docLang =
        typeof document !== "undefined"
          ? document.documentElement.lang
          : undefined;
      lang = isLocale(docLang) ? docLang : "fa";
    }
  }

  config.headers["Accept-Language"] = lang;
  config.headers["X-User-Language"] = lang;

  return config;
});

http.interceptors.response.use(
  (response) => response,
  (error) => Promise.reject(error),
);