import java.applet.Applet;
import java.awt.*;

public class Siteit extends java.applet.Applet{
	TextArea ans = new TextArea("Polar: Bearing and distance are calculated\nRect: Target coordinates are calculated",1,5,1);
	TextField seText= new TextField(2);
	TextField snText= new TextField(2);
	TextField teText= new TextField(2);
	TextField tnText= new TextField(2);
	TextField rText= new TextField(2);
	TextField wcbText= new TextField(2);
	
	protected void addGridLabel(String labelName,int align,GridBagLayout gb,
								GridBagConstraints gbc){
		Label label=new Label(labelName,align);
		gb.setConstraints(label,gbc);
		add(label);
	}
	protected void addGridField(TextField textfield,GridBagLayout gb,
								GridBagConstraints gbc){
		gb.setConstraints(textfield,gbc);
		add(textfield);
	}
	protected void addGridArea(TextArea textarea,GridBagLayout gb,
								GridBagConstraints gbc){
		gb.setConstraints(textarea,gbc);
		add(textarea);
	}	
	protected void addGridButton(Button button,GridBagLayout gb,
								GridBagConstraints gbc){
		gb.setConstraints(button,gbc);
		add(button);
	}	
	public void init(){
	resize(300,300);
	GridBagLayout gridbag=new GridBagLayout();
	GridBagConstraints c =new GridBagConstraints();
	setLayout(gridbag);
	c.fill=GridBagConstraints.BOTH;
	c.gridwidth=GridBagConstraints.REMAINDER;
	//c.gridheight=2;
	c.weighty=1;
	addGridLabel("Java Bearing Calculator",1,gridbag,c);
	c.weighty=0;
	c.gridheight=1;
	c.gridwidth=3;
	addGridLabel("Station East",1,gridbag,c);
	c.weightx=1.5;
	
	//c.weightx=1.5;
	addGridField(seText,gridbag,c);
	c.weightx=1;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.gridheight=1;
	c.gridwidth=3;
	c.weightx=0;
	addGridLabel("Station North",1,gridbag,c);
	c.weightx=1.5;
	
	addGridField(snText,gridbag,c);
	c.weightx=1;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.gridheight=1;
	c.gridwidth=3;
	c.weightx=0;
	addGridLabel("Target East",1,gridbag,c);
	
	c.weightx=1.5;
	addGridField(teText,gridbag,c);
	c.weightx=1.0;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.gridheight=1;
	c.gridwidth=3;
	c.weightx=0;
	addGridLabel("Target North",1,gridbag,c);
	
	c.weightx=1.5;
	addGridField(tnText,gridbag,c);
	c.weightx=1.0;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.gridheight=1;
	c.gridwidth=3;
	c.weightx=0;
	addGridLabel("Distance",1,gridbag,c);
	
	c.weightx=1.5;
	addGridField(rText,gridbag,c);
	c.weightx=1.0;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.gridheight=1;
	c.gridwidth=3;
	c.weightx=0;
	addGridLabel("Bearing",1,gridbag,c);
	
	c.weightx=1.5;
	addGridField(wcbText,gridbag,c);
	c.weightx=1;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("Please Enter Bearing in Form DDD:MM:SS",1,gridbag,c);
	Button polar = new Button("Polar");
	Button rect  = new Button("Rect");
	c.gridheight=1;
	c.gridwidth=3;
	c.weightx=0;
	addGridLabel("",1,gridbag,c);
	c.weightx=1.5;
	addGridButton(polar,gridbag,c);
	c.weightx=1;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.gridheight=1;
	c.gridwidth=3;
	c.weightx=0;
	addGridLabel("",1,gridbag,c);
	c.weightx=1.5;
	addGridButton(rect,gridbag,c);
	c.weightx=1;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridLabel("",1,gridbag,c);
	c.weighty=1;
	c.gridwidth=GridBagConstraints.REMAINDER;
	addGridArea(ans,gridbag,c);
	}
	
	public boolean action(Event evt, Object obj){
		double se, sn, te, tn,dis,rad;
		if(evt.target instanceof Button){
			ans.setText("Polar: Bearing and distance are calculated\nRect: Target coordinates are calculated");
			String buttonName=(String)obj;
			try{
				se = new Double(seText.getText()).doubleValue();
			}catch(NumberFormatException e){
				ans.setText("Station East is not a valid Number");
				return true;
			}
			try{
				sn = new Double(snText.getText()).doubleValue();
			}catch(NumberFormatException e){
				ans.setText("Station North is not a valid Number");
				return true;
			}	
			if (buttonName.equals("Polar")){
				try{
					te = new Double(teText.getText()).doubleValue();
				}catch(NumberFormatException e){
					ans.setText("Target East is not a valid Number");
					return true;
				}	
				try{
					tn = new Double(tnText.getText()).doubleValue();
				}catch(NumberFormatException e){
					ans.setText("Target North is not a valid Number");
					return true;
				}	
				pol(se,sn,te,tn);
			}else{
				try{
					dis = new Double(rText.getText()).doubleValue();
				}catch(NumberFormatException e){
					ans.setText("Distance is not a valid Number");
					return true;
				}
				try{
					rad = flIna(wcbText.getText());
				}catch(NumberFormatException e){
					ans.setText("Bearing is not in valid format \nExample 45:00:00");
					return true;
				}	
				rect(se,sn,dis,rad);	
			}	
			return true;
		}
		return false;
	}
	
	public void pol(double se,double sn, double te, double tn){
		double diffe =te-se;
		double diffn =tn-sn;
		rText.setText(flFix(Math.sqrt(diffe*diffe+diffn*diffn)));
		wcbText.setText(flDMS(rad2bear(diffe,diffn)));
			
	}	
	public String flFix(double num){
		double formatnum =Math.round(num*1000)/1000.0;
		String strans=new String().valueOf(formatnum);
		return strans ;
	}	
		
	public double rad2bear(double de,double dn){
		int quad=1;
		double radbear;
		if (dn<0 ){
			if (de<0 ){
				quad = 3;
            }else{
				quad = 2;
            }
		}
		if ((dn>0)&&(de<0)){
			quad = 4;
        }
		if (Math.abs(dn)>0 ){
			radbear =Math.atan(de/dn);
		}else{
			radbear = Math.PI/2;
			if (de<0 ){
				radbear+= Math.PI;
            }
		}
		if (quad == 2 ){
			radbear+= Math.PI;
		}
		if (quad ==3 ) {
			radbear+= Math.PI;
		}
		if (quad == 4 ) {
			radbear+= Math.PI*2;
		}
		if ((Math.abs(de)<0.001) &&(Math.abs(dn)<0.001)){
			radbear = 0;
		}
		return radbear;
	}

	
	public String flDMS (double radang){
		String strAng;
		int degs,mins,secs;
		double dmsang,dsecs,temp;
		dmsang = radang *180/Math.PI;
		while ( dmsang<360 ){
			dmsang+=360;
		}
		while ( dmsang>=360 ){
			dmsang-=360;
		}
		degs=(int)Math.floor(dmsang);
		mins=(int)Math.floor((dmsang-degs)*60);
		dsecs = (dmsang-degs-mins/60.0)*3600;
		temp = dsecs -Math.floor(dsecs);
		if (temp > 0.5 ){
			dsecs +=1;
		}
		secs = (int)Math.floor(dsecs);
		if (secs ==60 ){
			secs=0; mins+=1 ;
		}
		if (mins ==60 ){
			mins = 0 ; degs+=1;
		}
		if (degs ==360 ){
			degs = 0;
		}
		
		String strdegs=new String().valueOf(degs);
		String strmins=new String().valueOf(mins);
		if (strmins.length()<2){
			strmins="0"+strmins;
		}	
		String strsecs=new String().valueOf(secs);
		if (strsecs.length()<2){
			strsecs="0"+strsecs;
		}
		strAng=strdegs+":"+strmins+":"+strsecs;
		return strAng;
	}
	public double flIna(String dms)throws NumberFormatException{
		double myrad=0;
		int myang[] = new int[3];
		int cnt=0;
		int st=1;
		int ed=0;
		int sl;
		String tmp;
		dms=":"+ dms.trim() + ":";
		sl = dms.length();
		if(dms.length()<8){
			throw new NumberFormatException();
		}
		do{
			ed = dms.indexOf(":",st);
			if (ed != -1){
				tmp = dms.substring(st,ed);
				st = ed + 1;
				myang[cnt]=new Integer(tmp).intValue();
				cnt++;
			}
		}while ((ed !=-1) && (ed != (dms.length()-1)));
		myrad = myang[0] + myang[1]/60.0 +myang[2]/3600.0;
		myrad =Math.PI *myrad/180.0;  
	
		return myrad;
	}	
	public void rect(double se,double sn,double dis, double rad){
		teText.setText(flFix(se+dis*Math.sin(rad)));
		tnText.setText(flFix(sn+dis*Math.cos(rad)));
	}	

}