/*
 * Copyright 1999-2018 Alibaba Group Holding Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.alibaba.nacos.security.nacos.users;

import com.alibaba.nacos.config.server.auth.UserPersistService;
import com.alibaba.nacos.config.server.model.Page;
import com.alibaba.nacos.config.server.model.User;
import com.alibaba.nacos.core.auth.AuthConfigs;
import com.alibaba.nacos.core.utils.Loggers;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Service;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

/**
 * Custem user service.
 *
 * @author wfnuser
 * @author nkorange
 */
@Service
public class NacosUserDetailsServiceImpl implements UserDetailsService {

	private Map<String, User> userMap = new ConcurrentHashMap<>();

	@Autowired
	private UserPersistService userPersistService;

	@Autowired
	private AuthConfigs authConfigs;

	@Scheduled(initialDelay = 5000, fixedDelay = 15000)
	private void reload() {
		try {
			Page<User> users = getUsersFromDatabase(1, Integer.MAX_VALUE);
			if (users == null) {
				return;
			}

			Map<String, User> map = new ConcurrentHashMap<>(16);
			for (User user : users.getPageItems()) {
				map.put(user.getUsername(), user);
			}
			userMap = map;
		}
		catch (Exception e) {
			Loggers.AUTH.warn("[LOAD-USERS] load failed", e);
		}
	}

	@Override
	public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {

		User user = userMap.get(username);
		if (!authConfigs.isCachingEnabled()) {
			user = userPersistService.findUserByUsername(username);
		}

		if (user == null) {
			throw new UsernameNotFoundException(username);
		}
		return new NacosUserDetails(user);
	}

	public void updateUserPassword(String username, String password) {
		userPersistService.updateUserPassword(username, password);
	}

	public Page<User> getUsersFromDatabase(int pageNo, int pageSize) {
		return userPersistService.getUsers(pageNo, pageSize);
	}

	public User getUser(String username) {
		User user = userMap.get(username);
		if (!authConfigs.isCachingEnabled()) {
			user = getUserFromDatabase(username);
		}
		return user;
	}

	public User getUserFromDatabase(String username) {
		return userPersistService.findUserByUsername(username);
	}

	public void createUser(String username, String password) {
		userPersistService.createUser(username, password);
	}

	public void deleteUser(String username) {
		userPersistService.deleteUser(username);
	}

}
