import axios from 'axios';
import { message } from 'antd';
import { getRequestErrorMessage, isAuthSessionFailure } from './authSessionPolicy';
import { requestDesktopSessionRenewal } from '../utils/desktopEmbedSession';

const DEFAULT_REQUEST_TIMEOUT_MS = Math.max(
  Number(import.meta.env.VITE_API_REQUEST_TIMEOUT_MS) || 120000,
  15000
);

const request = axios.create({
  baseURL: '', // Proxy handles the base URL
  timeout: DEFAULT_REQUEST_TIMEOUT_MS,
});
const AUTH_USER_STORAGE_KEY = 'auth_user';

function clearAuthSession() {
  localStorage.removeItem('token');
  localStorage.removeItem(AUTH_USER_STORAGE_KEY);
}

function parseJwtPayload(token) {
  if (!token) {
    return null;
  }

  try {
    const [, payload] = token.split('.');
    if (!payload) {
      return null;
    }

    const normalized = payload.replace(/-/g, '+').replace(/_/g, '/');
    const padded = normalized.padEnd(normalized.length + ((4 - normalized.length % 4) % 4), '=');
    return JSON.parse(window.atob(padded));
  } catch {
    return null;
  }
}

function isLocalPreviewSession() {
  const isLocalHost = ['localhost', '127.0.0.1'].includes(window.location.hostname);
  if (!isLocalHost) {
    return false;
  }

  const payload = parseJwtPayload(localStorage.getItem('token'));
  return payload?.authSource === 'local-preview';
}

function isPublicAuthPage() {
  return ['/login', '/callback', '/install'].includes(window.location.pathname);
}

function shouldBypass401Redirect(error) {
  const url = error?.config?.url || '';
  return url.includes('/api/auth/verify') || isLocalPreviewSession();
}

// Request interceptor
request.interceptors.request.use(
  (config) => {
    const token = localStorage.getItem('token');
    if (token) {
      config.headers['Authorization'] = `Bearer ${token}`;
    }
    return config;
  },
  (error) => {
    return Promise.reject(error);
  }
);

// Response interceptor
request.interceptors.response.use(
  (response) => {
    const res = response.data;
    // Compatible with backend interfaces that don't return code
    if (res && res.code && res.code !== 200) {
      const shouldBypassRedirect = res.code === 401 && shouldBypass401Redirect(response);

      if (!shouldBypassRedirect && !response.config?.silentError) {
        message.error(res.message || 'Error');
      }
      
      if (res.code === 401 && !shouldBypassRedirect) {
        // Handle unauthorized - 但如果已在登录页则不重定向
        clearAuthSession();
        if (!isPublicAuthPage()) {
          if (!requestDesktopSessionRenewal('api-unauthorized')) {
            window.location.href = '/login';
          }
        }
      }
      return Promise.reject(new Error(res.message || 'Error'));
    }
    return res;
  },
  (error) => {
    const authSessionFailure = isAuthSessionFailure(error.response);
    if (!authSessionFailure && !error.config?.silentError) {
      message.error(getRequestErrorMessage(error));
    }
    if (authSessionFailure && !shouldBypass401Redirect(error)) {
      clearAuthSession();
      // 如果已在登录页则不重定向，避免无限循环
      if (!isPublicAuthPage()) {
        if (!requestDesktopSessionRenewal('api-unauthorized')) {
          window.location.href = '/login';
        }
      }
    }
    return Promise.reject(error);
  }
);

export default request;