/*
 * 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 org.apache.jmeter.functions;

import java.io.Serializable;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import org.apache.jmeter.engine.util.CompoundVariable;
import org.apache.jmeter.samplers.SampleResult;
import org.apache.jmeter.samplers.Sampler;
import org.apache.jmeter.threads.JMeterVariables;
import org.apache.jmeter.util.JMeterUtils;

/**
 * Provides a longSum function that adds two or more long values.
 * @see IntSum
 */
public class LongSum extends AbstractFunction implements Serializable {

	private static final long serialVersionUID = 232L;
	
	private static final List desc = new LinkedList();

	private static final String KEY = "__longSum"; //$NON-NLS-1$

	static {
		desc.add(JMeterUtils.getResString("longsum_param_1")); //$NON-NLS-1$
		desc.add(JMeterUtils.getResString("longsum_param_2")); //$NON-NLS-1$
		desc.add(JMeterUtils.getResString("function_name_paropt")); //$NON-NLS-1$
	}

	private Object[] values;

	/**
	 * No-arg constructor.
	 */
	public LongSum() {
	}

	/**
	 * Clone this Add object.
	 * 
	 * @return A new Add object.
	 * @throws CloneNotSupportedException 
	 */
	public Object clone() throws CloneNotSupportedException {
		return super.clone();
	}

	/**
	 * Execute the function.
	 * 
	 * @see Function#execute(SampleResult, Sampler)
	 */
	public synchronized String execute(SampleResult previousResult, Sampler currentSampler)
			throws InvalidVariableException {

		JMeterVariables vars = getVariables();

		long sum = 0;
		String varName = ((CompoundVariable) values[values.length - 1]).execute().trim();

		for (int i = 0; i < values.length - 1; i++) {
			sum += Long.parseLong(((CompoundVariable) values[i]).execute());
		}

        try {
            sum += Long.parseLong(varName);
            varName = null; // there is no variable name
        } catch (NumberFormatException ignored) {
        }
        
		String totalString = Long.toString(sum);
		if (vars != null && varName != null && varName.length() > 0){// vars will be null on TestPlan
			vars.put(varName, totalString);
		}

		return totalString;

	}

	/**
	 * Set the parameters for the function.
	 * 
	 * @see Function#setParameters(Collection)
	 */
	public synchronized void setParameters(Collection parameters) throws InvalidVariableException {
		checkMinParameterCount(parameters, 2);
		values = parameters.toArray();
	}

	/**
	 * Get the invocation key for this function.
	 * 
	 * @see Function#getReferenceKey()
	 */
	public String getReferenceKey() {
		return KEY;
	}

	/**
	 * Get the description of this function.
	 * 
	 * @see Function#getArgumentDesc()
	 */
	public List getArgumentDesc() {
		return desc;
	}
}
