// $Header: /home/cvs/jakarta-jmeter/src/functions/org/apache/jmeter/functions/CSVRead.java,v 1.14 2004/03/30 18:07:07 sebb Exp $
/*
 * Copyright 2003-2004 The Apache Software Foundation.
 *
 * 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.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.util.JMeterUtils;
import org.apache.jorphan.logging.LoggingManager;
import org.apache.log.Logger;

/**
 * The function represented by this class allows data to be read from CSV
 * files.  Syntax is similar to StringFromFile function.  The function allows
 * the test to line-thru the data in the CSV file - one line per each test.
 * E.g. inserting the following in the test scripts :
 * 
 *   ${_CSVRead(c:/BOF/abcd.csv,0)}       // read (first) line of
'c:/BOF/abcd.csv' , return the 1st column ( represented by the '0'),
 *   ${_CSVRead(c:/BOF/abcd.csv,1)}       // read (first) line of
'c:/BOF/abcd.csv' , return the 2nd column ( represented by the '1'),
 *   ${_CSVRead(c:/BOF/abcd.csv,next())}  // Go to next line of
'c:/BOF/abcd.csv'
 *
 * NOTE: A single instance of each different file is opened and used for all threads.
 * 
 * To open the same file twice, use the alias function:
 *  __CSVRead(abc.csv,*ONE);
 *  __CSVRead(abc.csv,*TWO);
 * 
 *  __CSVRead(*ONE,1); etc
 * 
 *
 * @version $Revision: 1.14 $ Last Updated: $Date: 2004/03/30 18:07:07 $
 */
public class CSVRead extends AbstractFunction implements Serializable
{
    transient private static final Logger log = LoggingManager.getLoggerForClass();

    private static final String KEY = "__CSVRead"; // Function name

    private static final List desc = new LinkedList();

    
    private Object[] values; // Parameter list
    
    static {
        desc.add(JMeterUtils.getResString("csvread_file_file_name"));
        desc.add(JMeterUtils.getResString("column_number"));
    }

    public CSVRead()
    {
    }

    public Object clone()
    {
        CSVRead newReader = new CSVRead();
        return newReader;
    }

    /**
     * @see org.apache.jmeter.functions.Function#execute(SampleResult, Sampler)
     */
    public synchronized String execute(
        SampleResult previousResult,
        Sampler currentSampler)
        throws InvalidVariableException
    {
    	String myValue = "";

        String fileName =
                ((org.apache.jmeter.engine.util.CompoundVariable) values[0])
                    .execute();
        String columnOrNext =
                ((org.apache.jmeter.engine.util.CompoundVariable) values[1])
                    .execute();

		log.debug("execute (" + fileName + " , " + columnOrNext + ")   ");

        // Process __CSVRead(filename,*ALIAS)
        if (columnOrNext.startsWith("*"))
        {
            FileWrapper.open(fileName,columnOrNext);
            /*
             * All done, so return
             */
            return "";
        }  
            
        // if argument is 'next' - go to the next line
        if (columnOrNext.equals("next()") || columnOrNext.equals("next"))
        {
        	FileWrapper.endRow(fileName);
        
            /*
             * All done now ,so return the empty string - this allows the caller to
             * append __CSVRead(file,next) to the last instance of __CSVRead(file,col)
             * 
             * N.B. It is important not to read any further lines at this point, otherwise
             * the wrong line can be retrieved when using multiple threads. 
             */
             return "";
        }

        try
        {
            int columnIndex = Integer.parseInt(columnOrNext); // what column is wanted?
            myValue = FileWrapper.getColumn(fileName,columnIndex);
        }
        catch (NumberFormatException e)
        {
            log.warn(Thread.currentThread().getName()+" - can't parse column number: " 
                     + columnOrNext + " "+ e.toString());
        }
		catch (IndexOutOfBoundsException e)
		{
			log.warn(Thread.currentThread().getName()+" - invalid column number: " + columnOrNext
			          + " at row " + FileWrapper.getCurrentRow(fileName) + " "
			          + e.toString());
		}

        log.debug("execute value: "+myValue);
        
        return myValue;
    }

    /**
     * @see org.apache.jmeter.functions.Function#getArgumentDesc()
     */
    public List getArgumentDesc()
    {
        return desc;
    }

    /**
     * @see org.apache.jmeter.functions.Function#getReferenceKey()
     */
    public String getReferenceKey()
    {
        return KEY;
    }
    
    /**
     * @see org.apache.jmeter.functions.Function#setParameters(Collection)
     */
    public void setParameters(Collection parameters)
        throws InvalidVariableException
    {
   		log.debug("setParameter - Collection.size=" + parameters.size());

        values = parameters.toArray();

		if (log.isDebugEnabled()){
			for (int i=0;i