/*
 *    WriteStreamToARFFFile.java
 *    Copyright (C) 2007 University of Waikato, Hamilton, New Zealand
 *    @author Richard Kirkby (rkirkby@cs.waikato.ac.nz)
 *
 *    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 2 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, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
package tr.gov.ulakbim.jDenetX.tasks;

import tr.gov.ulakbim.jDenetX.core.ObjectRepository;
import tr.gov.ulakbim.jDenetX.options.ClassOption;
import tr.gov.ulakbim.jDenetX.options.FileOption;
import tr.gov.ulakbim.jDenetX.options.FlagOption;
import tr.gov.ulakbim.jDenetX.options.IntOption;
import tr.gov.ulakbim.jDenetX.streams.InstanceStream;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.Writer;

public class WriteStreamToARFFFile extends MainTask {

    @Override
    public String getPurposeString() {
        return "Outputs a stream to an ARFF file.";
    }

    private static final long serialVersionUID = 1L;

    public ClassOption streamOption = new ClassOption("stream", 's',
            "Stream to write.", InstanceStream.class,
            "generators.RandomTreeGenerator");

    public FileOption arffFileOption = new FileOption("arffFile", 'f',
            "Destination ARFF file.", null, "arff", true);

    public IntOption maxInstancesOption = new IntOption("maxInstances", 'm',
            "Maximum number of instances to write to file.", 10000000, 0,
            Integer.MAX_VALUE);

    public FlagOption suppressHeaderOption = new FlagOption("suppressHeader",
            'h', "Suppress header from output.");

    @Override
    protected Object doMainTask(TaskMonitor monitor, ObjectRepository repository) {
        InstanceStream stream = (InstanceStream) getPreparedClassOption(this.streamOption);
        File destFile = this.arffFileOption.getFile();
        if (destFile != null) {
            try {
                Writer w = new BufferedWriter(new FileWriter(destFile));
                monitor.setCurrentActivityDescription("Writing stream to ARFF");
                if (!this.suppressHeaderOption.isSet()) {
                    w.write(stream.getHeader().toString());
                    w.write("\n");
                }
                int numWritten = 0;
                while ((numWritten < this.maxInstancesOption.getValue())
                        && stream.hasMoreInstances()) {
                    w.write(stream.nextInstance().toString());
                    w.write("\n");
                    numWritten++;
                }
                w.close();
            } catch (Exception ex) {
                throw new RuntimeException(
                        "Failed writing to file " + destFile, ex);
            }
            return new String("Stream written to ARFF file " + destFile);
        }
        throw new IllegalArgumentException("No destination file to write to.");
    }

    public Class<?> getTaskResultType() {
        return String.class;
    }

}