import axios, { AxiosError, AxiosInstance, AxiosRequestConfig, AxiosResponse } from "axios";
import { ElMessage } from "element-plus";
import router from "../router";
import { getToken } from "../utils/auth";
import { useAuthStore } from "../store/auth";
import type { ApiError } from "../types/api";
import { useStudyStore } from "../store/study";
import { TEXT } from "../locales";

let unauthorizedNotified = false;

const instance: AxiosInstance = axios.create({
  baseURL: "/",
  timeout: 15000,
});

instance.interceptors.request.use((config: AxiosRequestConfig) => {
  const token = getToken();
  if (token) {
    config.headers = config.headers || {};
    config.headers.Authorization = `Bearer ${token}`;
  }
  return config;
});

instance.interceptors.response.use(
  (response: AxiosResponse) => response,
  async (error: AxiosError<ApiError>) => {
    const status = error.response?.status;
    const data = error.response?.data;
    const reqUrl = error.config?.url || "";
    const isAuthEndpoint = reqUrl.includes("/api/v1/auth/login") || reqUrl.includes("/api/v1/auth/register");
    if (isAuthEndpoint) {
      // 认证相关的错误由具体页面自行处理，避免重复提示
      return Promise.reject(error);
    }
    // 401 统一处理：同步清理本地 token，并防止重复弹窗
    const handleUnauthorized = () => {
      const auth = useAuthStore();
      auth.logout();
      if (!unauthorizedNotified) {
        unauthorizedNotified = true;
        ElMessage.error(data?.message || TEXT.common.messages.sessionExpired);
        setTimeout(() => {
          unauthorizedNotified = false;
        }, 1000);
      }
      router.push("/login");
    };
    // 如果当前项目不存在或已失效，清理项目并跳到工作台
    if (status === 404 && typeof data?.message === "string" && data.message.toLowerCase().includes("study")) {
      try {
        const studyStore = useStudyStore();
        studyStore.clearCurrentStudy();
      } catch {
        /* ignore */
      }
      router.push("/workbench");
    }
    if (status === 401) {
      handleUnauthorized();
    } else if (data?.message) {
      ElMessage.error(data.message);
    } else {
      ElMessage.error(TEXT.common.messages.requestFailed);
    }
    return Promise.reject(error);
  }
);

export const apiGet = <T = unknown>(url: string, config?: AxiosRequestConfig) => instance.get<T>(url, config);
export const apiPost = <T = unknown>(url: string, data?: unknown, config?: AxiosRequestConfig) =>
  instance.post<T>(url, data, config);
export const apiPatch = <T = unknown>(url: string, data?: unknown, config?: AxiosRequestConfig) =>
  instance.patch<T>(url, data, config);
export const apiDelete = <T = unknown>(url: string, config?: AxiosRequestConfig) =>
  instance.delete<T>(url, config);

export default instance;