import axios from 'axios';
import { toast } from 'sonner';
import { useUserStore } from '../store/userStore';

const getBaseURL = () => {
  if (process.env.NEXT_PUBLIC_API_URL) return process.env.NEXT_PUBLIC_API_URL;
  if (typeof window === 'undefined') {
    return 'http://127.0.0.1:4400/api';
  }
  return process.env.NODE_ENV === 'development' ? 'http://localhost:4400/api' : '/api';
};

const baseURL = getBaseURL();
export const BASE_DOMAIN = process.env.NEXT_PUBLIC_API_URL?.replace('/api', '') || (typeof window !== 'undefined' && process.env.NODE_ENV === 'development' ? 'http://localhost:4400' : '');

export interface ApiErrorPayload {
  success: boolean;
  statusCode: number;
  message: string;
  code: string;
  details?: Array<{ field: string; message: string }> | Record<string, unknown>;
  timestamp?: string;
  path?: string;
}

const api = axios.create({
  baseURL,
  timeout: 10000,
  headers: {
    'Content-Type': 'application/json',
  },
});

// Interceptor to add auth token in request headers
api.interceptors.request.use(
  (config) => {
    let token: string | null = null;
    if (typeof window !== 'undefined' && window.localStorage) {
      try {
        token = localStorage.getItem('accessToken');
      } catch (e) {
        console.warn('Storage access restricted:', e);
      }
    }
    if (token && config.headers) {
      config.headers.Authorization = `Bearer ${token}`;
    }
    return config;
  },
  (error) => Promise.reject(error)
);

// Interceptor to handle 401/403, automatic refresh token rotation, and standardized toasts
let isRefreshing = false;
let failedQueue: Array<{
  resolve: (value: unknown) => void;
  reject: (reason?: unknown) => void;
}> = [];

const processQueue = (error: unknown, token: string | null = null) => {
  failedQueue.forEach((prom) => {
    if (error) {
      prom.reject(error);
    } else {
      prom.resolve(token);
    }
  });
  failedQueue = [];
};

api.interceptors.response.use(
  (response) => response,
  async (error) => {
    const originalRequest = error.config;

    // Handle 401 Unauthorized with token refresh retry
    if (
      typeof window !== 'undefined' &&
      error.response?.status === 401 &&
      !originalRequest?._retry &&
      !originalRequest?.url?.includes('/auth/')
    ) {
      if (isRefreshing) {
        return new Promise((resolve, reject) => {
          failedQueue.push({ resolve, reject });
        })
          .then((token) => {
            originalRequest.headers.Authorization = `Bearer ${token}`;
            return api(originalRequest);
          })
          .catch((err) => Promise.reject(err));
      }

      originalRequest._retry = true;
      isRefreshing = true;

      const refreshToken = localStorage.getItem('refreshToken');
      if (refreshToken) {
        try {
          const res = await axios.post(
            `${baseURL}/auth/refresh-token`,
            { refreshToken },
            { headers: { 'Content-Type': 'application/json' } }
          );

          const { accessToken, refreshToken: newRefreshToken } = res.data?.data || {};
          if (accessToken) {
            localStorage.setItem('accessToken', accessToken);
            if (newRefreshToken) {
              localStorage.setItem('refreshToken', newRefreshToken);
            }
            api.defaults.headers.common.Authorization = `Bearer ${accessToken}`;
            originalRequest.headers.Authorization = `Bearer ${accessToken}`;
            processQueue(null, accessToken);
            isRefreshing = false;
            return api(originalRequest);
          }
        } catch (refreshErr) {
          processQueue(refreshErr, null);
          isRefreshing = false;
        }
      } else {
        isRefreshing = false;
      }

      // If refresh failed or no refresh token exists, clear state and logout
      if (window.localStorage) {
        try {
          localStorage.removeItem('accessToken');
          localStorage.removeItem('refreshToken');
        } catch {}
      }
      try {
        useUserStore.getState().logout();
      } catch {}
    }

    if (typeof window !== 'undefined') {
      const responseData = error.response?.data as ApiErrorPayload | undefined;
      const status = error.response?.status;
      const farsiMessage = responseData?.message || 'خطایی در ارتباط با سرور رخ داده است.';

      if (status === 403) {
        if (window.localStorage) {
          try {
            localStorage.removeItem('accessToken');
            localStorage.removeItem('refreshToken');
          } catch {}
        }
        try {
          useUserStore.getState().logout();
        } catch {
          // Ignore if store not ready
        }
      }

      // Show formatted Farsi toast if not explicitly suppressed and not 401/403/404
      if (!error.config?.hideErrorToast && status !== 401 && status !== 403 && status !== 404) {
        let fullMessage = farsiMessage;
        if (responseData?.details && Array.isArray(responseData.details) && responseData.details.length > 0) {
          const detailStrings = responseData.details
            .map((d: unknown) => typeof d === 'string' ? d : ((d as Record<string, string>)?.message || (d as Record<string, string>)?.field))
            .filter(Boolean);
          if (detailStrings.length > 0) {
            const joinedDetails = detailStrings.join('، ');
            if (!farsiMessage.includes(joinedDetails)) {
              fullMessage = `${farsiMessage} (${joinedDetails})`;
            }
          }
        }
        toast.error(fullMessage, { id: fullMessage });
        (error as unknown as Record<string, boolean>)._toastShown = true;
      }
    }
    return Promise.reject(error);
  }
);

export default api;