/*
    Movie digitizer
 */

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

public class digflow extends Applet {
    public MediaTracker tracker, trackerBg;
	public Image offScreenImage;
	public Image theBox, theBack;
	public boolean copyRight = false;
	public boolean digiflag = true, plotflag = false;
	public char cr = '\r', lf = '\n';		// cr works on the Mac, but not on Unix or Windows

	public String theImageName = "p01.jpg";
	public int numPict = 1;
	public int xdigi[] = new int[100], ydigi[] = new int[100];
	
	public double yi[] = new double[100];
	
	public void init() {
		super.init();		
		offScreenImage = createImage(500,360);

		//{{INIT_CONTROLS
		setLayout(null);
		resize(620,360);
		textArea1 = new java.awt.TextArea();
		textArea1.reshape(500,0,120,360);
		textArea1.setFont(new Font("Courier", Font.PLAIN, 10));
		add(textArea1);
		//}}
		
		trackerBg = new MediaTracker(this);
		theBack = this.getImage(getCodeBase(),"bg.jpg");
		trackerBg.addImage(theBack,0);
		try {
	    	trackerBg.waitForID(0);
		} catch (InterruptedException e) {
		}
		
		getNextImage(theImageName);
		repaint();
	}

	public void update(Graphics g){
		Graphics offg = offScreenImage.getGraphics();
		paint(offg);
		g.drawImage(offScreenImage, 0, 0, this);
	}

	public void getNextImage(String theName){
		tracker= new MediaTracker(this);
		theBox = this.getImage(getCodeBase(),theName);
		tracker.addImage(theBox,0);
		try {
	    	tracker.waitForID(0);
		} catch (InterruptedException e) {
		}
	}

	public void paint(Graphics g){
		g.setColor(Color.white);
		g.fillRect(0,0,500,360);
		g.drawImage(theBack,0,0,theBack.getWidth(this),theBack.getHeight(this),this);
		if (digiflag) {
			g.fillRect(0,0,350,360);
			g.drawImage(theBox,0,0,theBox.getWidth(this),theBox.getHeight(this),this);
		}
		
		// labels:  active ones are red, passive are gray
		g.setFont(new Font("Helvetica", Font.BOLD, 14));
		g.setColor(Color.blue);
		g.drawString("Undo Pt.",433,121);
		
		g.setColor(Color.darkGray);
		if (plotflag && digiflag) g.setColor(Color.red);
		g.drawString("Plot y(x)",433,88);
		
		if (digiflag) {
			g.setColor(Color.red);
			g.drawString("Digitize",433,22);
			g.setColor(Color.darkGray);
			g.drawString("Plot h(t)",433,55);
		} else {
			g.setColor(Color.darkGray);
			g.drawString("Digitize",433,22);
			g.setColor(Color.red);
			g.drawString("Plot h(t)",433,55);
		}
		
		// data points
		g.setColor(Color.red);
		if (plotflag && digiflag) {
			for (int i=1; i<numPict; i++) {
				g.fillOval(xdigi[i]-2,ydigi[i]-2,5,5);
			}
		}
		
		if (!digiflag) {
			for (int i=1; i<numPict; i++) {
				g.fillOval(18+i*8,ydigi[i]+30,5,5);
			}
		}
				
		g.setColor(Color.red);
		g.setFont(new Font("Helvetica", Font.PLAIN, 18));
		g.drawString("t = "+outString(""+((numPict-1)*3),3)+" s",370,320);
		
		// display the raw click data in the text area:
		String derText = " t(s), y(m)";
		for (int i=1; i<numPict; i++) {
			String ts = outString(""+((i-1)*3),3);
			if (i == 1) ts = "0";
			String ys = ", "+outString(""+yi[i],6);
			derText = derText+lf+ts+ys;
		}
		textArea1.setText(derText);

		
		// copyright notice:
		if (copyRight) {
			g.setColor(Color.green);
			g.fillRect(100,100,240,70);
			g.setColor(Color.white);
			g.setFont(new Font("Helvetica", Font.PLAIN, 18));
			g.drawString("This applet was written by:",110,120);
			g.drawString("Wolfgang Bauer",110,140);
			g.drawString("Copyright: WB 2000",110,160);
		}
	}

	public boolean handleEvent(Event event) {
		if (event.id == Event.KEY_PRESS){
			String thePressedKey = ""+(char)event.key;
			if (thePressedKey.equalsIgnoreCase("w")) {
				copyRight = !copyRight;
	            repaint();
			}
		}
		if (event.target == this && event.id == Event.MOUSE_UP) {
			digitize_MouseUp(event);
			return true;
		}
		return super.handleEvent(event);
	}

	//{{DECLARE_CONTROLS
	java.awt.TextArea textArea1;
	//}}

	public String outString(String inString, int l){    // returns the first l chars of string
		int ls = (int)Math.min(inString.length(),l);
		return inString.substring(0,ls);
	}

	void digitize_MouseUp(Event event) {
		int xx = event.x;
		int yy = event.y;
		
		if (digiflag && xx < theBox.getWidth(this)) {
			// record coordinate
			xdigi[numPict] = xx;
			ydigi[numPict] = yy;
			yi[numPict] = 0.5 * (295 - yy) / 300.;  // calibrated height in m
			// load new picture
			numPict++;
			if (numPict < 10) {
				theImageName = "p0"+numPict+".jpg";
			} else {
				theImageName = "p"+numPict+".jpg";
			}
			getNextImage(theImageName);
			repaint();
		}
		
		if (xx > 423 && yy < 133 && yy > 101 && numPict > 1) {
			numPict--;
			if (numPict < 10) {
				theImageName = "p0"+numPict+".jpg";
			} else {
				theImageName = "p"+numPict+".jpg";
			}
			getNextImage(theImageName);
			repaint();
		}

		
		if (xx > 423 && yy < 100 && yy > 68) {
			plotflag = !plotflag;
			repaint();
		}

		if (xx > 423 && yy < 33 && yy > 2) {
			digiflag = true;
			repaint();
		}

		if (xx > 423 && yy < 66 && yy > 35) {
			digiflag = false;
			repaint();
		}

	}

}