import java.io.IOException;
import java.io.PrintStream;
import java.util.Iterator;

/**
 * Small class to generate a crude histogram plot.
 * 
 * @author geoffreytowell
 *
 */
public class Histogrammer
{
    /**
     * The histogram marker
     */
    private static final String MARK = "X";
    
    /**
     * Write a histogram to System.out
     * @param hdata the data to be plotted
     */
    public void fauxHistogram(int[] hdata)
    {
	fauxHistogram(hdata, System.out);
    }
    
    /**
     * Write a histogram to the named file
     * @param hdata the data to be plotted
     * @param filename the file to be written to
     */
    public void fauxHistogram(int[] hdata, String filename)
    {
	try
	{
	    PrintStream fileWriter = new PrintStream("c:/temp/samplefile3.txt");
	    fauxHistogram(hdata, fileWriter);
	    fileWriter.close();
	}
	catch (IOException ioe)
	{
	    System.err.println(ioe.toString());
	}
    }
    
    /**
     * Write a histogram to the PrintWriter
     * @param hdata the data to be plotted
     * @param ps the PrintWriter to which to write
     */
    public void fauxHistogram(int[] hdata, PrintStream ps)
    {
	// first get the highest and lowest non-zero data points
	int ff=-1; 
	int ll=-1;
	for (int i=0; i<hdata.length; i++)
	{
	    if (hdata[i]>0 && ff<0)
		ff=i;
	    if (hdata[i]>0)
		ll=i;
	}
	if (ff<0)
	    ps.println("No data to Histogram");
	
	// Now plot the data, showing only from lowest to highest
	for (int i=ff; i<=ll; i++)
	{
	    // use String.format to make things look nice
	    ps.print(String.format("%2d (%4d)", i, hdata[i]));
	    // ternary operator limits printing to 70 marks
	    for (int j=0; j<(hdata[i]<=70?hdata[i]:70); j++)
		ps.print(MARK);
	    ps.println();
	}
    }

    public static void main(String[] args)
    {
	DataProvider dg = new DataProvider(50, 500);
	dg.setRange(50);
	Iterator<Integer> itr = dg.iterator();
	int[] data = new int[50];
	while(itr.hasNext())
	{
	    int tmp = itr.next();
	    if (tmp>0)
		data[tmp-1]++;
	}
	new Histogrammer().fauxHistogram(data);
    }
}