import axios, { AxiosResponse, AxiosError } from 'axios';
import { toast } from 'react-hot-toast';
import {
  Todo,
  TodoCreate,
  TodoUpdate,
  TodoFilter,
  TodosResponse,
  User,
  UserPreferences,
  LdapUser,
  LoginRequest,
  LoginResponse,
  FireEmailRequest,
  FireEmailQuota,
  ImportJob,
} from '@/types';

const API_BASE_URL = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:5000';

// Create axios instance
const api = axios.create({
  baseURL: API_BASE_URL,
  timeout: 30000,
});

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

// Response interceptor for error handling
api.interceptors.response.use(
  (response) => response,
  async (error: AxiosError) => {
    const originalRequest = error.config as any;

    if (error.response?.status === 401 && !originalRequest._retry) {
      originalRequest._retry = true;

      try {
        const refreshToken = localStorage.getItem('refresh_token');
        if (refreshToken) {
          const response = await api.post('/api/auth/refresh', {}, {
            headers: { Authorization: `Bearer ${refreshToken}` },
          });
          
          const { access_token } = response.data;
          localStorage.setItem('access_token', access_token);
          
          // Retry original request (mark it to skip toast on failure)
          originalRequest._isRetry = true;
          return api(originalRequest);
        }
      } catch (refreshError) {
        // Refresh failed, redirect to login
        localStorage.removeItem('access_token');
        localStorage.removeItem('refresh_token');
        localStorage.removeItem('user');
        window.location.href = '/login';
        return Promise.reject(refreshError);
      }
    }

    // Show error toast (skip for retry requests to avoid duplicates)
    if (!originalRequest._isRetry) {
      const errorData = (error as any).response?.data;
      const status = (error as any).response?.status;
      let errorMessage = 'An error occurred';
      
      if (errorData?.message) {
        errorMessage = errorData.message;
      } else if (errorData?.error) {
        errorMessage = errorData.error;
      } else if ((error as any).message) {
        errorMessage = (error as any).message;
      }
      
      // Special handling for database connection errors
      if (status === 503) {
        toast.error(errorMessage, {
          duration: 5000,
          style: {
            backgroundColor: '#fef3c7',
            color: '#92400e',
          },
        });
      } else if (status === 504) {
        toast.error(errorMessage, {
          duration: 4000,
          style: {
            backgroundColor: '#fee2e2',
            color: '#991b1b',
          },
        });
      } else if (status !== 401) {
        toast.error(errorMessage);
      }
    }

    return Promise.reject(error);
  }
);

// Auth API
export const authApi = {
  login: async (credentials: LoginRequest): Promise<LoginResponse> => {
    const response = await api.post('/api/auth/login', credentials);
    return response.data;
  },

  logout: async (): Promise<void> => {
    await api.post('/api/auth/logout');
    localStorage.removeItem('access_token');
    localStorage.removeItem('refresh_token');
    localStorage.removeItem('user');
  },

  getCurrentUser: async (): Promise<User> => {
    const response = await api.get('/api/auth/me');
    return response.data;
  },

  validateToken: async (): Promise<boolean> => {
    try {
      await api.get('/api/auth/validate');
      return true;
    } catch {
      return false;
    }
  },
};

// Todos API
export const todosApi = {
  getTodos: async (filter: TodoFilter & { page?: number; per_page?: number }): Promise<TodosResponse> => {
    const params = new URLSearchParams();
    
    Object.entries(filter).forEach(([key, value]) => {
      if (value !== undefined && value !== null && value !== '') {
        params.append(key, value.toString());
      }
    });

    const response = await api.get(`/api/todos?${params.toString()}`);
    return response.data;
  },

  getTodo: async (id: string): Promise<Todo> => {
    const response = await api.get(`/api/todos/${id}`);
    return response.data;
  },

  createTodo: async (todo: TodoCreate): Promise<Todo> => {
    const response = await api.post('/api/todos', todo);
    return response.data;
  },

  updateTodo: async (id: string, updates: Partial<TodoUpdate>): Promise<Todo> => {
    const response = await api.patch(`/api/todos/${id}`, updates);
    return response.data;
  },

  deleteTodo: async (id: string): Promise<void> => {
    await api.delete(`/api/todos/${id}`);
  },

  batchUpdateTodos: async (todoIds: string[], updates: Partial<TodoUpdate>): Promise<{ updated: number; errors: any[] }> => {
    const response = await api.patch('/api/todos/batch', {
      todo_ids: todoIds,
      updates,
    });
    return response.data;
  },

  fireEmail: async (request: FireEmailRequest): Promise<void> => {
    await api.post('/api/notifications/fire-email', {
      todo_id: request.todo_id,
      message: request.note,
    });
  },
};

// Users API
export const usersApi = {
  searchUsers: async (query: string): Promise<LdapUser[]> => {
    const response = await api.get(`/api/users/search?q=${encodeURIComponent(query)}`);
    return response.data.users;
  },

  getPreferences: async (): Promise<UserPreferences> => {
    const response = await api.get('/api/users/preferences');
    return response.data;
  },

  updatePreferences: async (preferences: Partial<UserPreferences>): Promise<UserPreferences> => {
    const response = await api.patch('/api/users/preferences', preferences);
    return response.data;
  },

  getFireEmailQuota: async (): Promise<FireEmailQuota> => {
    const response = await api.get('/api/users/fire-email-quota');
    return response.data;
  },
};

// Import API
export const importApi = {
  downloadTemplate: async (): Promise<Blob> => {
    const response = await api.get('/api/imports/template', {
      responseType: 'blob',
    });
    return response.data;
  },

  uploadFile: async (file: File): Promise<ImportJob> => {
    const formData = new FormData();
    formData.append('file', file);
    
    const response = await api.post('/api/imports', formData, {
      headers: {
        'Content-Type': 'multipart/form-data',
      },
    });
    return response.data;
  },

  getImportJob: async (jobId: string): Promise<ImportJob> => {
    const response = await api.get(`/api/imports/${jobId}`);
    return response.data;
  },

  downloadErrors: async (jobId: string): Promise<Blob> => {
    const response = await api.get(`/api/imports/${jobId}/errors`, {
      responseType: 'blob',
    });
    return response.data;
  },
};


// Admin API (if needed)
export const adminApi = {
  getStats: async (days: number = 30): Promise<any> => {
    const response = await api.get(`/api/admin/stats?days=${days}`);
    return response.data;
  },

  getAuditLogs: async (params: any): Promise<any> => {
    const queryParams = new URLSearchParams(params).toString();
    const response = await api.get(`/api/admin/audit-logs?${queryParams}`);
    return response.data;
  },

  getMailLogs: async (params: any): Promise<any> => {
    const queryParams = new URLSearchParams(params).toString();
    const response = await api.get(`/api/admin/mail-logs?${queryParams}`);
    return response.data;
  },
};

// Notifications API
export const notificationsApi = {
  getSettings: async (): Promise<any> => {
    const response = await api.get('/api/notifications/settings');
    return response.data;
  },

  updateSettings: async (settings: any): Promise<any> => {
    const response = await api.patch('/api/notifications/settings', settings);
    return response.data;
  },

  sendTestEmail: async (recipientEmail?: string): Promise<void> => {
    await api.post('/api/notifications/test', recipientEmail ? { recipient_email: recipientEmail } : {});
  },

  sendDigest: async (type: 'weekly' | 'monthly' = 'weekly'): Promise<void> => {
    await api.post('/api/notifications/digest', { type });
  },

  markNotificationRead: async (notificationId: string): Promise<void> => {
    await api.post('/api/notifications/mark-read', { notification_id: notificationId });
  },

  markAllNotificationsRead: async (): Promise<void> => {
    await api.post('/api/notifications/mark-all-read');
  },

  getNotifications: async (): Promise<any> => {
    const response = await api.get('/api/notifications/');
    return response.data;
  },
};

// Health API
export const healthApi = {
  check: async (): Promise<any> => {
    const response = await api.get('/api/health/healthz');
    return response.data;
  },

  readiness: async (): Promise<any> => {
    const response = await api.get('/api/health/readiness');
    return response.data;
  },
};

export default api;