import axios from "axios";
import { useAuthStore } from "@/stores/auth";

const AUTH_ERROR_CODE = 401;
const SESSION_REPLACED_CODE = 40101;

const http = axios.create({
  baseURL: import.meta.env.VITE_API_BASE_URL || "/api",
  timeout: 15000,
  headers: {
    Accept: "application/json",
    "Content-Type": "application/json",
  },
});

let redirectingToLogin = false;

function redirectToLogin(reason) {
  const currentPath = window.location.pathname.replace(/\/+$/, "") || "/";
  if (currentPath === "/login" || redirectingToLogin) return;

  redirectingToLogin = true;
  const redirect = `${window.location.pathname}${window.location.search}${window.location.hash}`;
  const query = new URLSearchParams({ redirect });
  if (reason) query.set("reason", reason);
  window.location.assign(`/login?${query.toString()}`);
}

function isAuthenticationError(code) {
  return code === AUTH_ERROR_CODE || code === SESSION_REPLACED_CODE;
}

function handleUnauthorized(code) {
  const authStore = useAuthStore();
  authStore.clearSession();
  redirectToLogin(code === SESSION_REPLACED_CODE ? "session-replaced" : "expired");
}

http.interceptors.request.use((config) => {
  const authStore = useAuthStore();

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

  return config;
});

http.interceptors.response.use(
  (response) => {
    const payload = response.data;

    if (payload?.code === undefined) return payload;
    const result = {
      ...payload,
      success: payload.code === 0,
    };
    if (result.success) return result;

    if (isAuthenticationError(result.code)) handleUnauthorized(result.code);

    const error = new Error(result.message || "请求失败");
    error.code = result.code;
    error.data = result.data;
    error.success = result.success;
    throw error;
  },
  (error) => {
    const status = error.response?.status;
    const payload = error.response?.data;

    const authenticationCode = payload?.code ?? status;
    if (isAuthenticationError(authenticationCode)) handleUnauthorized(authenticationCode);

    const requestError = new Error(
      payload?.message ||
        (error.code === "ECONNABORTED" ? "请求超时，请稍后重试" : "网络异常，请检查服务是否正常"),
    );
    requestError.code = payload?.code ?? status;
    requestError.data = payload?.data;
    requestError.success = false;
    throw requestError;
  },
);

export function post(path, data, config) {
  return http.post(path, data, config);
}

export default http;