package de.ugoe.cs.cpdp.loader;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;

import weka.core.Attribute;
import weka.core.DenseInstance;
import weka.core.Instances;
import de.ugoe.cs.cpdp.loader.AbstractFolderLoader.SingleVersionLoader;
import de.ugoe.cs.util.FileTools;

/**
 * Loads the instances for a software version from a CSV file of the // TODO dataset citation
 * data set. 
 * @author Steffen Herbold
 */
class CSVDataLoader implements SingleVersionLoader {
	
	/**
	 * Loads the instances.
	 * @param file handle to the file of the instances
	 * @return the instances
	 */
	@Override
	public Instances load(File file) {
		final String[] lines;
		try {
			lines = FileTools.getLinesFromFile(file.getAbsolutePath());
		} catch (IOException e) {
			throw new RuntimeException(e);
		}
		
		// configure Instances
		final ArrayList<Attribute> atts = new ArrayList<Attribute>();
		
		String[] lineSplit = lines[0].split(",");		
		for( int j=0 ; j<lineSplit.length-4 ; j++ ) {
			atts.add(new Attribute(lineSplit[j+3]));
		}
		final ArrayList<String> classAttVals = new ArrayList<String>();
		classAttVals.add("0");
		classAttVals.add("1");
		final Attribute classAtt = new Attribute("bug", classAttVals);
		atts.add(classAtt);
		
		final Instances data = new Instances(file.getName(), atts, 0);
		data.setClass(classAtt);
		
		// fetch data
		for( int i=1 ; i<lines.length ; i++ ) {
			lineSplit = lines[i].split(",");
			double[] values = new double[lineSplit.length-3];
			for( int j=0 ; j<values.length-1 ; j++ ) {
				values[j] = Double.parseDouble(lineSplit[j+3].trim());
			}
			values[values.length-1] = lineSplit[lineSplit.length-1].trim().equals("0") ? 0 : 1;
			data.add(new DenseInstance(1.0, values));
		}
		
		return data;
	}
	
	@Override
	public boolean filenameFilter(String filename) {
		return filename.endsWith(".csv");
	}

}