import java.net.*;
import java.io.*;
import spotless.*;

/**
 * This class implements the functionality of a "soft"
 * remote control for the Lego tanks, using the palm.
 * It provides a simple GUI with "up", "down", "left",
 * "right", "stop", and "fire" buttons. The palm does
 * not communicate with the tank directly, but rather
 * sends the commands to a desktop first (where cmds
 * are queued and sequentialized for later transmission
 * to the tanks). The reason for this is potential 
 * interference between two palms trying to issue commands
 * at the same time. The desktop, as a point of synchronization,
 * eliminates that problem by providing only a single device
 * for IR transmissions.
 * 

 * Communication between the desktop and the palm is handled
 * through sockets.
 * 

 * On a desktop, this code would define at least one interface,
 * and define a bunch of symbolic constants. Unfortunately, we
 * currently don't have space for that.
 */
public class TankRemote extends Spotlet {

	/** tank has bumped into something */
	public static final byte B_OBSTRUCTED = (byte)1;

	/** tank has been hit by laser */
	public static final byte B_HIT = (byte)1 << 1;

	/** an error occured on the desktop side */
	public static final byte B_ERROR = (byte)1 << 2;

	/** the palm registered successfully with a tank */
	public static final byte B_REGISTER = (byte)1 << 3;
	
	private OutputStream out;
	private InputStream in;
	private String cmd;
	private Socket socket;
	private Button exitButton;
	private Button forward;
	private Button backward;
	private Button left;
	private Button right;
	private Button stop;
	private Button status;
	private Button fire;
	
	/** system entry point */
	public static void main(String[] args) {
		(new TankRemote()).register();
	}
	
	/** 
	 * Create a new TankRemote instance. This brings up the GUI
	 * and initializes the socket connection.
	 */
	public TankRemote() {
		// up arrow bitmap
		byte[] up = {
			(byte)0, (byte)0, (byte)1, (byte)128, 
			(byte)3, (byte)192, (byte)7, (byte)224, (byte)15, 
			(byte)240, (byte)31, (byte)248, (byte)63, (byte)252, 
			(byte)127, (byte)254, (byte)0, (byte)0
		};
		forward = new Button(new Bitmap((short)2, up), 70, 40);
		up = null;
		Runtime.gc();
		
		// down arrow bitmap
		byte[] down = {
			(byte)0, (byte)0, (byte)127, (byte)254, 
			(byte)63, (byte)252, (byte)31, (byte)248, (byte)15, 
			(byte)240, (byte)7, (byte)224, (byte)3, (byte)192, 
			(byte)1, (byte)128, (byte)0, (byte)0
		};
		backward = new Button(new Bitmap((short)2, down), 70, 80);
		down = null;
		Runtime.gc();
		
		// right arrow bitmap
		byte[] rturn = {
			(byte)0, (byte)0, (byte)96, (byte)0, 
			(byte)126, (byte)0, (byte)127, (byte)224, (byte)127, 
			(byte)254, (byte)127, (byte)224, (byte)126, (byte)0, 
			(byte)96, (byte)0, (byte)0, (byte)0
		};
		right = new Button(new Bitmap((short)2, rturn), 105, 60);
		rturn = null;
		Runtime.gc();
		
		// left arrow bitmap
		byte[] lturn = {
			(byte)0, (byte)0, (byte)0, (byte)6, 
			(byte)0, (byte)126, (byte)7, (byte)254, (byte)127, 
			(byte)254, (byte)7, (byte)254, (byte)0, (byte)126, 
			(byte)0, (byte)6, (byte)0, (byte)0
		};
		left = new Button(new Bitmap((short)2, lturn), 35, 60);
		lturn = null;
		Runtime.gc();
		
		// stop circle bitmap
		byte[] halt = {
			(byte)0, (byte)0, (byte)3, (byte)192, 
			(byte)31, (byte)248, (byte)63, (byte)252, (byte)63, 
			(byte)252, (byte)63, (byte)252, (byte)31, (byte)248, 
			(byte)3, (byte)192, (byte)0, (byte)0
		};
		stop = new Button(new Bitmap((short)2, halt), 70, 60);
		halt = null;
		Runtime.gc();
		
		// status query bitmap
		byte[] why = {
			(byte)0, (byte)0, (byte)3, (byte)192, (byte)6, 
			(byte)96, (byte)0, (byte)192, (byte)1, (byte)128, (byte)1, 
			(byte)128, (byte)0, (byte)0, (byte)1, (byte)128, (byte)0, (byte)0
		};
		status = new Button(new Bitmap((short)2, why), 105, 105);
		why = null;
		Runtime.gc();
		
		// fire bang bitmap
		byte[] bang = {
			(byte)  0, (byte)  0, (byte)  1, (byte)128, (byte)  1, 
			(byte)128, (byte)  1, (byte)128, (byte)  1, (byte)128, (byte)  1, 
			(byte)128, (byte)  0, (byte)  0, (byte)  1, (byte)128, (byte)  0, (byte)0
		};
		fire = new Button(new Bitmap((short)2, bang), 35, 105);
		bang = null;
		Runtime.gc();
		
		exitButton = new Button("Exit", 120, 145);
		
		Graphics.clearScreen();
		paint();
		
		byte newline;
		
		try {
			// make the connection to the desktop
			socket = new Socket("129.146.42.139", 9595);
			out = socket.getOutputStream();
			in = socket.getInputStream();
			
			for (int i = 0; i < 3; i++) {
				// try to register with a tank
				out.write("register\n".toByteArray());

				displayStatus((byte)in.read());
				newline = (byte) in.read();
				Thread.sleep(20);
			}
		} catch(Exception e) {
			abort(e.toString());
			try { socket.close(); } 
			catch (Exception x) {}
			Runtime.exit();
		}
	}
	
	
	/** 
	 * inform user of interesting or important status 
	 * feedback from the tank.
	 */
	private void displayStatus(byte status) {
		Graphics.drawRectangle(7, 2, 152, 35, Graphics.ERASE, 0);
		if ((status & B_ERROR) != 0) abort("An error occured");
		if ((status & B_HIT) != 0) abort("Aaargh. I'm hit!");
		if ((status & B_OBSTRUCTED) != 0) Graphics.drawString("Bumped into something.", 50, 20);
		if ((status & B_REGISTER) != 0) Graphics.drawString("Register succeeded.", 50, 20);
	}
	
	/** Inform user that a fatal eror has occured and bail */
	private void abort(String msg) {
		Graphics.drawString(msg + ". Aborting...", 50, 20);
		try { socket.close(); }
		catch (Exception e) {}
		Thread.sleep(1000);
		Runtime.exit();
	}
	
	/** redraw the GUI */
	private void paint() {
		Graphics.resetDrawRegion();
		Graphics.drawBorder(6, 1, 153, 133, Graphics.PLAIN, Graphics.SIMPLE);
		Graphics.drawRectangle(0, 140, 160, 20, Graphics.ERASE, 0);
		
		exitButton.paint();
		forward.paint();
		backward.paint();
		left.paint();
		right.paint();
		stop.paint();
		status.paint();
		fire.paint();
		
		Graphics.setDrawRegion(6, 1, 153, 133);
	}
	
	/** 
	 * Call back method after a pen down event
	 * has been detected by the palm
	 */
	public void penDown(int x, int y) {
		String cmd = null;
		byte reply;
		byte newline;
		
		Runtime.gc();
		
		try {
			if (exitButton.pressed(x, y)) {
				socket.close();
				Runtime.exit();
			}
			
			if (forward.pressed(x, y)) cmd = "forward";
			if (backward.pressed(x, y)) cmd = "backward";
			if (left.pressed(x, y)) cmd = "left";
			if (right.pressed(x, y)) cmd = "right";
			if (stop.pressed(x, y)) cmd = "stop";
			if (status.pressed(x, y)) cmd = "status";
			if (fire.pressed(x, y)) cmd = "fire";
			
			if (cmd == null) return ;
			
			out.write((cmd + "\n").toByteArray());
			reply = (byte) in.read();
			newline = (byte) in.read();
			displayStatus(reply);
		} catch (Exception e) {
			abort(e.toString());
			try {socket.close();} catch(Exception ee) {}
			Runtime.exit();
		}
	}
}