/**
 * API Service
 *
 * Axios configuration and API client for backend communication
 */

import axios, { AxiosInstance, InternalAxiosRequestConfig } from 'axios';

const API_URL = process.env.REACT_APP_API_URL || 'http://localhost:8000/api/v1';

// Create axios instance
const apiClient: AxiosInstance = axios.create({
  baseURL: API_URL,
  headers: {
    'Content-Type': 'application/json',
  },
});

// Request interceptor to add auth token
apiClient.interceptors.request.use(
  (config: InternalAxiosRequestConfig) => {
    const token = localStorage.getItem('access_token');

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

    return config;
  },
  (error) => {
    return Promise.reject(error);
  }
);

// Response interceptor for error handling
apiClient.interceptors.response.use(
  (response) => response,
  async (error) => {
    const originalRequest = error.config;

    // Handle 401 errors (token expired)
    if (error.response?.status === 401 && !originalRequest._retry) {
      originalRequest._retry = true;

      try {
        const refreshToken = localStorage.getItem('refresh_token');

        if (refreshToken) {
          const response = await axios.post(`${API_URL}/auth/refresh`, {
            refresh_token: refreshToken,
          });

          const { access_token } = response.data;
          localStorage.setItem('access_token', access_token);

          // Retry original request with new token
          originalRequest.headers.Authorization = `Bearer ${access_token}`;
          return apiClient(originalRequest);
        }
      } catch (refreshError) {
        // Refresh failed, clear tokens and redirect to login
        localStorage.removeItem('access_token');
        localStorage.removeItem('refresh_token');
        window.location.href = '/';
        return Promise.reject(refreshError);
      }
    }

    return Promise.reject(error);
  }
);

export default apiClient;

// API methods
export const authAPI = {
  login: (idToken: string) =>
    apiClient.post('/auth/login', { id_token: idToken }),

  loginSimple: (email: string, password: string) =>
    apiClient.post('/auth/login/simple', { email, password }),

  logout: () =>
    apiClient.post('/auth/logout'),

  getCurrentUser: () =>
    apiClient.get('/auth/me'),

  refreshToken: (refreshToken: string) =>
    apiClient.post('/auth/refresh', { refresh_token: refreshToken }),
};

export const conversationAPI = {
  list: (includeArchived: boolean = false, skip: number = 0, limit: number = 50) =>
    apiClient.get('/conversations', {
      params: { include_archived: includeArchived, skip, limit },
    }),

  create: (title?: string) =>
    apiClient.post('/conversations', { title }),

  get: (id: string) =>
    apiClient.get(`/conversations/${id}`),

  update: (id: string, title: string) =>
    apiClient.put(`/conversations/${id}`, { title }),

  archive: (id: string) =>
    apiClient.post(`/conversations/${id}/archive`),

  delete: (id: string) =>
    apiClient.delete(`/conversations/${id}`),
};

export const messageAPI = {
  list: (conversationId: string, skip: number = 0, limit: number = 100) =>
    apiClient.get(`/conversations/${conversationId}/messages`, {
      params: { skip, limit },
    }),

  send: (conversationId: string, content: string) =>
    apiClient.post(`/conversations/${conversationId}/messages`, { content }),
};

export const tokenAPI = {
  getUsage: (days: number = 30) =>
    apiClient.get('/tokens/usage', { params: { days } }),

  getUsersUsage: (days: number = 30) =>
    apiClient.get('/tokens/users', { params: { days } }),

  getDailyUsageByUser: (days: number = 30) =>
    apiClient.get('/tokens/daily-users', { params: { days } }),
};

export const adminAPI = {
  // User management
  listUsers: (skip: number = 0, limit: number = 100) =>
    apiClient.get('/admin/users', { params: { skip, limit } }),

  updateUserRole: (userId: string, role: string) =>
    apiClient.put(`/admin/users/${userId}/role`, { role }),

  activateUser: (userId: string) =>
    apiClient.put(`/admin/users/${userId}/activate`),

  deactivateUser: (userId: string) =>
    apiClient.put(`/admin/users/${userId}/deactivate`),

  // Analytics
  getSystemAnalytics: () =>
    apiClient.get('/admin/analytics/system'),

  getUsersAnalytics: (days: number = 30, limit: number = 50) =>
    apiClient.get('/admin/analytics/users', { params: { days, limit } }),

  getAllConversations: (skip: number = 0, limit: number = 50) =>
    apiClient.get('/admin/conversations/all', { params: { skip, limit } }),
};