package org.rosuda.util;

import java.awt.*;
import java.io.*;

/** tools to be used by all other classes
    @version $Id$
*/
public class Tools {
    /** displays a dialog box to save a file and returns the
	corresponding printstream for the newly created file
	@par par parent frame for the dialog (may NOT be <code>null</code>)
	@par title dialog title
	@par deffn default file name
	@return <code>null</code> if create failed or user canceled operation, the PrintStream otherwise.
    */
    public static PrintStream getNewOutputStreamDlg(Frame par,
						    String title,
						    String deffn) {
	FileDialog fd=new FileDialog(par,title,FileDialog.SAVE);
	if (deffn!=null) fd.setFile(deffn);
	fd.setModal(true);
	fd.show();
	String fnam="";

	if (fd.getDirectory()!=null) fnam+=fd.getDirectory();
	if (fd.getFile()!=null) fnam+=fd.getFile();
	else return null;
	  
	try {
	    PrintStream outs=new PrintStream(new FileOutputStream(fnam));
	    return outs;
	} catch(Exception e) {
	};
	return null;	
    };

    public static double nlogn(double n) {
        return (n<=0)?0:n*Math.log(n);
    }

    public static double nlogn(int n) {
        return (n<=0)?0.0:((double)n)*Math.log((double)n);
    }

    public static int[] sortDoublesIndex(double[] da) {
        int ct=da.length;
        int r[] = new int[ct];

        int i=0;
        while (i<ct) { r[i]=i; i++; }
        i=0;
        while (i<ct-1) {
            double d=da[r[i]];
            int j=ct-1;
            while (j>i) {
                double d2=da[r[j]];
                if (d2>d) {
                    int xx=r[i]; r[i]=r[j]; r[j]=xx;
                    d=d2;
                }
                j--;
            }
            i++;
        }
        return r;
    }

    public static int[] sortIntegersIndex(int[] da) {
        int ct=da.length;
        int r[] = new int[ct];

        int i=0;
        while (i<ct) { r[i]=i; i++; }
        i=0;
        while (i<ct-1) {
            int d=da[r[i]];
            int j=ct-1;
            while (j>i) {
                int d2=da[r[j]];
                if (d2>d) {
                    int xx=r[i]; r[i]=r[j]; r[j]=xx;
                    d=d2;
                }
                j--;
            }
            i++;
        }
        return r;
    }

    public static String getDisplayableValue(double val) { return getDisplayableValue(val,val); };
    
    public static String getDisplayableValue(double val, double range) {
        double vLenLog10=(range>0)?Math.log(range)/Math.log(10):0;
        int dac=((2-((int)vLenLog10))<0)?0:(2-((int)vLenLog10));
        return getDisplayableValue(val,dac);
    };

    public static String getDisplayableValue(double val, int dac) {
        /*
        String s=Double.toString(val);
        String ps="";
        int i;
        if (i=s.indexOf('E')) {
            ps="e"+s.substring(i+1);
            s=s.substring(0,i);
        }
        int digs=0;
        int len=0;
        i=0;
        while (i<s.length()) {
            if (s.charAt(i)>='0' && s.charAt(i)<='9') digs++;
        */

        String sig="";
        if (dac==0) return ""+((int)val);
        double mplr=10.0;
        long implr=10;
        for(int i=1; i<=dac; i++) { mplr*=10.0; implr*=10; };
        long front=(long)(Math.round(val*mplr)/mplr);
        mplr/=10.0; implr/=10;
        double post=(val-((double)front))*mplr;
        if (post<0) post=-post;
        long ipost=(long)Math.round(post);
        if (val<0 && front==0 && ipost>0) sig="-";
        if (ipost>=implr) {
            ipost-=implr;
            if (front>=0) front++; else front--;
        }
        String spost=""+ipost; while (spost.length()<dac) { spost="0"+spost; };
        return sig+front+((ipost==0)?"":"."+spost);
    };

    public static double parseDouble(String s) {
        double d=0;
        try {
            Double dd=Double.valueOf(s);
            d=dd.doubleValue();
        } catch(Exception dce) {};
        return d;
    }

    public static int parseInt(String s) {
        int i=0;
        try {
            Integer dd=Integer.valueOf(s);
            i=dd.intValue();
        } catch(Exception dce) {};
        return i;
    }

    public static int parseHexInt(String s) {
        int i=0;
        try {
            i=Integer.parseInt(s,16);
        } catch(Exception dce) {};
        return i;
    }    

    public static long parseHexLong(String s) {
        long i=0;
        try {
            i=Long.parseLong(s,16);
        } catch(Exception dce) {};
        return i;
    }

    public static String color2hrgb(Color c) {
        int i=(c.getRed()<<16)|(c.getGreen()<<8)|(c.getBlue());
        String s=Integer.toHexString(i);
        while (s.length()<6) { s="0"+s; };
        return "#"+s;
    }

    public static Color hrgb2color(String s) {
        if (s!=null && s.length()>0 && s.charAt(0)=='#') {
            int c=Tools.parseHexInt(s.substring(1));
            return new Color((c>>16)&255,(c>>8)&255,c&255);
        }
        return null;
    }
}