/*
 * WebimHashCluster.java
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 webim.service;

import javax.annotation.Resource;

import org.springframework.stereotype.Service;

import webim.WebimConfig;
import webim.client.WebimCluster;
import webim.model.WebimEndpoint;

/**
 * 默认基于用户id Hash方式集群
 * 
 * @author Feng Lee <feng.lee at nextalk.im>
 *
 */
@Service("webimCluster")
public class WebimHashCluster implements WebimCluster {
	
	@Resource(name="webimConfig")
	private WebimConfig config; 
	
	private String[] servers = null;
	
	public WebimHashCluster() {
	}

	@Override
	public String getServer(WebimEndpoint ep) {
		int hash = ep.getId().hashCode();
		if(servers == null) {
			servers = ((String)config.get("server")).split(",");
		}
		int idx = (hash & 0x7FFFFFFF) % servers.length;
		return servers[idx];
	}

}
