/*
 * Symphony - A modern community (forum/SNS/blog) platform written in Java.
 * Copyright (C) 2012-2017,  b3log.org & hacpai.com
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.b3log.symphony.cache;

import org.b3log.latke.Keys;
import org.b3log.latke.ioc.inject.Named;
import org.b3log.latke.ioc.inject.Singleton;
import org.b3log.latke.model.User;
import org.b3log.symphony.util.JSONs;
import org.json.JSONObject;

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

/**
 * User cache.
 *
 * @author <a href="http://88250.b3log.org">Liang Ding</a>
 * @version 1.1.0.0, Oct 2, 2017
 * @since 1.4.0
 */
@Named
@Singleton
public class UserCache {

    /**
     * Id, User.
     */
    private static final Map<String, JSONObject> ID_CACHE = new ConcurrentHashMap<>();

    /**
     * Name, User.
     */
    private static final Map<String, JSONObject> NAME_CACHE = new ConcurrentHashMap<>();

    /**
     * Gets a user by the specified user id.
     *
     * @param userId the specified user id
     * @return user, returns {@code null} if not found
     */
    public JSONObject getUser(final String userId) {
        final JSONObject user = ID_CACHE.get(userId);
        if (null == user) {
            return null;
        }

        return JSONs.clone(user);
    }

    /**
     * Gets a user by the specified user name.
     *
     * @param userName the specified user name
     * @return user, returns {@code null} if not found
     */
    public JSONObject getUserByName(final String userName) {
        final JSONObject user = NAME_CACHE.get(userName);
        if (null == user) {
            return null;
        }

        return JSONs.clone(user);
    }

    /**
     * Adds or updates the specified user.
     *
     * @param user the specified user
     */
    public void putUser(final JSONObject user) {
        ID_CACHE.put(user.optString(Keys.OBJECT_ID), JSONs.clone(user));
        NAME_CACHE.put(user.optString(User.USER_NAME), JSONs.clone(user));
    }

    /**
     * Removes the the specified user.
     *
     * @param user the specified user
     */
    public void RemoveUser(final JSONObject user) {
        ID_CACHE.remove(user.optString(Keys.OBJECT_ID));
        NAME_CACHE.remove(user.optString(User.USER_NAME));
    }
}
