/*
 * Copyright 2014 Eediom Inc.
 * 
 * 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 org.araqne.logdb.cep;

public class EventKey {
	private final String topic;
	private final String key;

	// optional host value for log tick
	private String host;

	private final int hashCode;

	public EventKey(String topic, String key, String host) {
		this.topic = topic;
		this.key = key;
		this.host = host;
		if (host != null)
			this.hashCode = topic.hashCode() ^ key.hashCode() ^ host.hashCode();
		else
			this.hashCode = topic.hashCode() ^ key.hashCode();
	}

	public String getTopic() {
		return topic;
	}

	public String getKey() {
		return key;
	}

	public String getHost() {
		return host;
	}

	@Override
	public int hashCode() {
		return hashCode;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;

		// must be same class
		if (getClass() != obj.getClass())
			return false;

		// topic and key is always not null
		EventKey other = (EventKey) obj;

		if (host == null) {
			if (other.host != null)
				return false;
			return key.equals(other.key) && topic.equals(other.topic);
		}

		return key.equals(other.key) && topic.equals(other.topic) && host.equals(other.host);
	}

	@Override
	public String toString() {
		if (host == null)
			return "topic=" + topic + ", key=" + key;
		return "topic=" + topic + ", key=" + key + ", host=" + host;
	}
}