//
// AstroCoords.java:
// Various coordinate classes useful for astronomical calculations.
//    Copyright 1996 by Akkana Peck.
//

// package Akk.Astro;

import java.lang.Math;
import java.awt.Graphics;
import java.awt.Button;
import java.awt.Event;
import java.awt.Font;
import java.applet.Applet;

// A data type to represent heliocentric coordinates:
class HelioCoords
{
    double x, y, r;
    double l;		// heliocentric longitude, useful for calculation

    public HelioCoords()
    { x=0.; y=0.; r=0.; l=0.; }
    public HelioCoords(double rr, double xx, double yy)
    { x=xx; y=yy; r=rr; l = 0; }
    public HelioCoords(double rr, double xx, double yy, double ll)
    { x=xx; y=yy; r=rr; l = ll; }
}

// A class that holds right ascension and declination:
class AstroCoords
{
    double RA, dec, dist;

    double get_RA_radians()	{ return RA; }
    double get_dec_radians()	{ return dec; }
    double get_RA_hours()	{ return RA * 12 / Math.PI; }
    double get_dec_degrees()	{ return dec * 180 / Math.PI; }

    public AstroCoords(double _ra, double _dec) {
	RA = _ra;
	dec = _dec;
    }

    public AstroCoords(double _ra, double _dec, double _dist) {
	RA = _ra;
	dec = _dec;
	dist = _dist;
    }

    public AstroCoords(String rastring, String decstring)
    {
	RA = getRAFromString(rastring);
	dec = getDecFromString(decstring);
    }

    double getRAFromString(String str)
    {
	double ret;

	int index = str.indexOf('h');
	if (index < 0)
	    index = str.indexOf(':');
	if (index >= 0)
	{
	    String sub = str.substring(0, index);
	    ret = Double.valueOf(sub).doubleValue();

	    str = str.substring(index+1);
	    index = str.indexOf('m');
	    if (index < 0)
		index = str.indexOf(':');
	    if (index > 0)
		sub = str.substring(0, index);
	    else
		sub = str;
	    ret += (Double.valueOf(sub).doubleValue() / 60.);
	    // ignore seconds for now, minutes is close enough
	}
	else
	    ret = Double.valueOf(str).doubleValue();

	// RA is now in decimal hours.  Convert to radians:
	ret *= Math.PI / 12;

	return ret;
    }

    double getDecFromString(String str)
    {
	double ret;

	int index = str.indexOf('^');
	if (index < 0)
	    index = str.indexOf(':');
	if (index >= 0)
	{
	    String sub = str.substring(0, index);
	    ret = Double.valueOf(sub).doubleValue();
	    str = str.substring(index+1);
	    index = str.indexOf('\'');
	    if (index < 0)
		index = str.indexOf(':');
	    if (index > 0)
		sub = str.substring(0, index);
	    else
		sub = str;
	    ret += (Double.valueOf(sub).doubleValue() / 60.);
	}
	else
	    ret = Double.valueOf(str).doubleValue();
	// ignore seconds for now, minutes is close enough

	// dec is now in decimal degrees.  Convert to radians:
	ret *= Math.PI / 180;

	return ret;
    }

    public void setRAFromString(String s) {
	RA = getRAFromString(s);
    }

    public void setDecFromString(String s) {
	dec = getDecFromString(s);
    }

    // Figure out whether we're inside some pair of arbitrary limits.
    // Account for the mod24 nature of right ascension,
    // and accept either -1 or 23 in either position.
    boolean inside(AstroCoords limit1, AstroCoords limit2)
    {
	// First check declination, since that's easy (dec doesn't wrap):
	if (dec < limit1.dec || dec > limit2.dec)
	    return false;

	// If our coordinate is negative, convert to positive:
	if (RA < 0)
	    RA += 2 * Math.PI;
	// and the same for limits:
	if (limit1.RA < 0)
	    limit1.RA += 2 * Math.PI;
	if (limit2.RA < 0)
	    limit2.RA += 2 * Math.PI;
	while (limit2.RA > 2*Math.PI)
	    limit2.RA -= 2*Math.PI;

	// Case 1: we're not wrapping through zero
	if (limit1.RA < limit2.RA)
	    return (RA >= limit1.RA && RA <= limit2.RA);

	// Case 2: we are wrapping through zero
	return (RA <= limit1.RA || RA >= limit2.RA);
    }

    public String toString()
    {
	double ra_deg = RA * 12 / Math.PI;
	Long ra_hours = new Long((long)ra_deg);
	double ra_frac = ra_deg - ra_hours.longValue();
	Long ra_min = new Long((long)(ra_frac*60));
	Float ra_sec = new Float((ra_frac * 60 - ra_min.longValue()) * 60);

	double dec_deg = dec * 180 / Math.PI;
	Long dec_int = new Long((long)dec_deg);
	double dec_frac = dec_deg - dec_int.longValue();
	Long dec_min = new Long((long)(Math.abs(dec_frac)*60));
	Long dec_sec = new Long((long)(Math.abs(dec_frac * 60
						- dec_min.longValue()) * 60));

	Double dd = new Double(dist);
	return "RA = " + ra_hours.toString() + "h "
	    + ra_min.toString() + "m "
//	    + ra_sec.toString() + "s "
	    + " Dec = " + dec_int.toString() + "^ "
	    + dec_min.toString() + "'"
//	    + dec_sec.toString() + "\""
	    + "   distance = " + dd.toString() + " AU";
    }
}

class XYCoord
{
	double x, y;

	public String toString()
	{
		return "(" + new Double(x).toString() + ", "
		       + new Double(y).toString() + ")";
	}
}