import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import java.util.*;
import java.io.*;
import java.applet.*;
import java.net.*;

public class Tour extends Applet {

TourMap map; // a map of nodes and views.
TourMap.Navigator navi; // a navigator for the map.
//ImageArea mainImage; // the main image
//ImageArea previewImage; // the preview image.
TextArea commentBox; // box to dsplay comments in.
Controller control; // the panel which has the movement controls on it.
LoresBtn loresBtn; // the button to toggle picture resolution.
Checkbox resolutionCheck; // checkbox to set image display resolution.
MediaTracker mTrack; // a media tracker for the images.
Image testImg;
byte previewDir; // the direction the preview window is pointing.
Image mainIm; // the main image
Image previewIm; // the preview image.

public static int imageSizes[][] = { {150,102} , {460,314}, {460,314} };
public static int CON_WIDTH=148; // width of the controller image.
public static int CON_HEIGHT=131;
public static int APPLET_WIDTH=650;
public static int APPLET_HEIGHT=400;
public static int LORES_WIDTH=71;
public static int LORES_HEIGHT=28;
public static int BACK_COLOR=0xffcc99;


public void init() {
	// read in the map, and set up the display area.
	mTrack = new MediaTracker(this);

	InputStream is=null;
	URL codeURL = getCodeBase();
	URL dataURL;
	URLConnection URLcon;
	try {
		StringBuffer fileStr = new StringBuffer(codeURL.getFile());
		fileStr.append("Tour.dat");
		System.out.println(fileStr);
		dataURL = new URL(codeURL.getProtocol(), codeURL.getHost(), fileStr.toString());
		is = dataURL.openStream();
			} catch (Exception e) {
				System.out.println(e);
				System.exit(1);
				}
	map = new TourMap();
	map.readFile(is);
	navi = map.GetNavigator();
	
	// set up the display.
	commentBox=new TextArea("",3,40,TextArea.SCROLLBARS_VERTICAL_ONLY);
	control=new Controller(getCodeBase(),490,150,this);
	loresBtn=new LoresBtn(getCodeBase(),490,300, this);
	
	BorderLayout bl = new BorderLayout();
	setLayout(bl);
	
	//Panel ctrlPanel= new Panel();
	//ctrlPanel.setLayout(new BorderLayout());		
	//ctrlPanel.add(control, BorderLayout.SOUTH);
	
	//add(ctrlPanel, BorderLayout.EAST);
	add(commentBox, BorderLayout.SOUTH);
	
	addMouseListener(new MouseHandler());
	addMouseMotionListener(new MouseMotionHandler());
	
	previewDir=(byte)8; // no preview to start with.
	updateComment(); // update the comment field.
	loadImage(navi.getView((byte)0), navi.getNode(), navi.getViewNo(), 2);
	waitForImage(navi.getNode(), navi.getViewNo(), 2);
	mainIm=navi.getView((byte)0).images[2];
	control.setButtons(navi,false);
	};
	
public void move(byte dir) {
	// move in a given direction. If dir = 0 then walk along the current view.
	// if dir>0 then turn to face direction dir.
	control.setButtons(navi,true); // show the wait indicator.
	control.setEnable(false);
	
	if (dir == 0) {
		navi.walk((byte)0);
	} else {
		navi.turn(dir);
		};

	setMainView();
	setPreview((byte)8);
	updateComment();
	doPaint();
	};
	
public void setMainView() {
	// set the main view image from the current navigator.
	int loadSize=2; // preferred size to load main image.
	int showSize; // size to show the image at.
	if (loresBtn.getState()) loadSize=1; // load low-res image.
	
	// check whether an image needs to be loaded:
	boolean loadIm;
	TourView mainView=navi.getView((byte)0);
	if (mainView.images[2] != null) {
		loadIm=false; // there's a big picture loaded, so no need to load another.
		showSize=2; // show the big picture.
	} else {
		showSize=loadSize;
		loadIm=(mainView.images[loadSize]==null);
		};		
	
	// load an image if necessary.
	if (loadIm) {
		showStatus("Loading main image - please wait...");
		doPaint();  //display the wait indicator.
		// now load the image.
		loadImage(mainView, navi.getNode(), navi.getViewNo(), loadSize);
		waitForImage(navi.getNode(), navi.getViewNo(), loadSize);
		showStatus("");
		};

	mainIm = mainView.images[showSize];
	control.setButtons(navi,false);
	control.setEnable(true);
	};
	
public void setPreview(byte dir) {
	// set the direction of the preview window. 8=  no preview.
	previewDir=(byte)8;
	if ((dir == 8) | (navi.canView(dir))) {
		previewDir=dir;
		if (dir !=8) {
			if (navi.getView((byte)dir).images[0] == null) {
				showStatus("Loading preview image - please wait ...");
				loadImage(navi.getView((byte)dir), navi.getNode(), 
						(byte)((navi.getViewNo() + dir ) % 8 ), 0);
				waitForImage(navi.getNode(),(byte)((navi.getViewNo() + dir) % 8), 0);
				showStatus("");
				};
			previewIm = navi.getView(previewDir).images[0];
			};
			
		doPaint();
		};
	}

public void updateComment() {
	// update the comment field to show details of the current view.
	TourView curView=navi.getView((byte)0); // this is the current view.
	String comment;
	comment = curView.comment;
	commentBox.setText(comment);
	};
	
public void loadImage(TourView view, TourNode node, byte dir, int size) {
	String iName; // name of the image file.
	if (view.images[size] == null) {
		int nodeNo = map.findNodeNo(node);
		iName="n" + nodeNo + "v" + (int)dir + "s" + size + ".jpg";
		try {
			URL imURL = new URL(getCodeBase().getProtocol(), getCodeBase().getHost(),
					getCodeBase().getFile() + "Images/");
			System.out.println("URL is:" + imURL);
			view.images[size]=getImage(imURL,iName).getScaledInstance(
					imageSizes[size][0], imageSizes[size][1], Image.SCALE_SMOOTH);
			mTrack.addImage(view.images[size], (nodeNo * 100) + (dir * 10) + size );
			} catch (Exception e) {
				System.out.println(e);
				System.exit(1);
				};
		System.out.println("Image " + iName + "Loaded");
		};
	};
	
public void waitForImage(TourNode node, byte dir, int size) {
	try {
		mTrack.waitForID((map.findNodeNo(node) * 100) + (dir * 10) + size);
		} catch (Exception e) {
			System.out.println(e);
			System.exit(1);
			};
	};

public void doPaint() {
	paint(getGraphics());
	}

public void paint(Graphics g) {
	// paint the applet: draw the main and preview images straight into the applet
	// window.
	
	Image buffIm = createImage(APPLET_WIDTH,APPLET_HEIGHT); // image for double buffer
	Graphics buffGraph = buffIm.getGraphics();
	buffGraph.setColor(new Color(BACK_COLOR));
	buffGraph.fillRect(0,0,APPLET_WIDTH,APPLET_HEIGHT);
	
	buffGraph.setColor(new Color(0,0,0));
	buffGraph.drawImage(mainIm,0,10,this);
	buffGraph.drawRect(0,10,imageSizes[2][0],imageSizes[2][1]);
	if (previewDir != (byte)8) {
		buffGraph.drawImage(previewIm,490,10,this);
		buffGraph.drawRect(490,10,imageSizes[0][0],imageSizes[0][1]);
		};
	control.paint(buffGraph); // paint the controller.
	loresBtn.paint(buffGraph); // paint the low res button;
	
	g.drawImage(buffIm,0,0,this);
	};
	
public class MouseHandler extends MouseAdapter {
	public void mouseClicked(MouseEvent me) {
		System.out.println("Mouse Event at: " + me.getX() + ", " + me.getY());
		control.mouseClicked(me);
		loresBtn.mouseClicked(me);
		};
	};
	
public class MouseMotionHandler extends MouseMotionAdapter {
		public void mouseMoved(MouseEvent me) {
			control.mouseMoved(me);
			}
	};

public class LoresBtn {
	// display a togglable button to switch between high and low resolution pictures.
	Image[] btnIm; // array of button face images.
								 // [0] is unselected (high res)
								 // [1] is selected (low res).
	int[][] btnPixels; // pixel array for button face image.
	Image[] btnMaskIm; // mask (alpha channel) images for the buttons.
	int[][] btnMaskPixels; // pixel array for mask.
	Image curBtnIm; // current button face to display.
	boolean pressed; // is the button pressed?
	Tour tour; // the tour that this button belongs to.
	int x,y; // the location of the button on the screen.
	MediaTracker mTrack;
	
	public LoresBtn(URL baseURL, int xPos, int yPos, Tour t) {
		// load and initialise the pictures, set button state etc.
		tour=t;
		x=xPos; y=yPos;
		mTrack=new MediaTracker(tour);
		btnIm=new Image[2];
		btnPixels=new int[2][];
		btnMaskIm=new Image[2];
		btnMaskPixels=new int[2][];
		// first load all the images...
		for (int i=0; i<2; i++) {
			try {
				btnIm[i]=getImage(baseURL,"lores" +i+ ".jpg");
				mTrack.addImage(btnIm[i],1);
				btnMaskIm[i]=getImage(baseURL,"loresm" + i + ".jpg");
				mTrack.addImage(btnMaskIm[i],1);
				}  catch (Exception e) {
					System.out.println("Error: " + e);
					};
			};
		try {
			mTrack.waitForID(1);
			} catch (Exception e) {
				System.out.println("Error: " + e);
				};
		System.out.println("Loaded low-res button images.");
		// now grab the image pixels into arrays.
		for (int i=0; i<2; i++) {
			btnPixels[i]=new int[LORES_WIDTH * LORES_HEIGHT];
			PixelGrabber pg=new PixelGrabber(btnIm[i],0,0,LORES_WIDTH,LORES_HEIGHT,
					btnPixels[i],0,LORES_WIDTH);
			btnMaskPixels[i]=new int[LORES_WIDTH * LORES_HEIGHT];
			PixelGrabber pg2=new PixelGrabber(btnMaskIm[i],0,0,LORES_WIDTH,LORES_HEIGHT,
					btnMaskPixels[i],0,LORES_WIDTH);
			try {
				pg.grabPixels();
				pg2.grabPixels();
				} catch (Exception e) {
					System.out.println("Error: " + e);
					};
			};
		// now merge the alpha channel info from the mask images into the face images.
		for (int i=0; i<2; i++) {
			for (int j=0; j < LORES_WIDTH * LORES_HEIGHT; j++) {
				btnPixels[i][j]=(btnPixels[i][j] & 0xffffff ) + 
						((btnMaskPixels[i][j] & 0xff) << 24 );
				};
			btnIm[i]=createImage(new MemoryImageSource(LORES_WIDTH,LORES_HEIGHT,
				btnPixels[i],0,LORES_WIDTH));
			};
		curBtnIm=btnIm[0];
		pressed=false;
		};
		
	public void paint(Graphics g) {
		// paint the button.
		g.drawImage(curBtnIm,x,y,tour);
		};
		
	public void mouseClicked(MouseEvent me) {
		// first check if the click was near the button.
		if ((me.getX() < x) | (me.getY() < y) | 
				(me.getX() >= x + LORES_WIDTH) | (me.getY() >= y + LORES_HEIGHT) )
			return;
		// now use the mask image to work out whether it hit the spot.
		int mousePix=btnMaskPixels[0][(me.getX() - x) + (me.getY() - y) * LORES_WIDTH];
		int blue=mousePix & 0xff;
		if (blue < 5) return; // didn't touch the button.
		// now change the button face and button state.
		if (pressed) {
			pressed = false;
			curBtnIm = btnIm[0];
			// switch to high res picture.
			tour.control.setButtons(tour.navi,true); // show the wait iindicator.
			tour.control.setEnable(false);
			tour.setMainView();
		} else {
			pressed = true;
			curBtnIm = btnIm[1];
			};
		tour.doPaint();
		};
		
	public boolean getState() {
		return pressed;
		};
		
	}; // end of class LoresBtn

public class Controller {
	// display a navigator object on the screen, and interpret mouse clicks over
	// the object
	Image[] conIm; // array of controller base images.
								 // [0] is just the central bit, normal state (orange).
								 // [1] is the central bit in image waiting state (blue).
								 // [2] is with the buttons, can't walk state (blue).
								 // [3] is with the buttons, can walk state (orange).
	Image selIm;   // an image whose pixel values describe how to render a controller
								 // image from the base images above.
								 // this is also used to interpret mouse clicks onto a button.
								 // the blue channel holds values from 0 to 180 in steps of 20, or 255
								 // - if the value is 0, then you are in the unchanged part of the image
								 // if the value is 20-160, then you are in the area of button no.
								 //    (val/20)-1. i.e. val=60 means button no.2
								 // if the value is 180, then you are in the area of the wait indicator.
	Image renIm;   // the current rendered controller image.
	int[][] conPixels; // arrays to hold the pixels for the 4 controller images.
	int[] selPixels; // array of selecter pixels
	MediaTracker mTrack;
	int x,y; // x and y coords to draw the controller at.
	Tour tour; // the tour of which this is the controller.
	boolean enabled; // is the controller enabled?
	int lastButtonHovered; // last button the mouse was hovered over.
									
	public Controller(URL baseURL, int xPos, int yPos, Tour t) {
		// initialise the controller - load button images
		// baseURL = URL to load images from; Xpos,yPos = where to draw the controller.
		x=xPos; y=yPos;
		tour=t;
		enabled=true;
		
		System.out.println();
		System.out.println("Initialising controller");
		mTrack=new MediaTracker(tour);
		conIm=new Image[4];
		conPixels=new int[4][];
		Image[] maskIm; // array of controller mask images
		maskIm=new Image[4];
		int[][] maskPixels; // array to store mask pixels.
		maskPixels=new int[4][];
		for (int i= 0; i<4 ; i++) {
			try {
				conIm[i]=getImage(baseURL,"control" + i + ".jpg");
				mTrack.addImage(conIm[i],1);
				maskIm[i]=getImage(baseURL,"conmask"+ i + ".jpg");
				mTrack.addImage(maskIm[i],1);
				} catch (Exception e) {
					System.out.println("Error: " + e);
					};
			};
		System.out.println("Loaded controller and mask images.");
		try {
			selIm=getImage(baseURL,"selecter.gif");
			mTrack.addImage(selIm,1);
			mTrack.waitForID(1);
			} catch (Exception e) {
				System.out.println("Error: " + e);
				};
		System.out.println("Loaded selecter image.");
		// now grab the pixels from each of the images into an array.
		for (int i=0; i<4; i++)  {
			conPixels[i]=new int[CON_WIDTH * CON_HEIGHT];
			PixelGrabber pg=new PixelGrabber(conIm[i],0,0,CON_WIDTH,CON_HEIGHT,
					conPixels[i],0,CON_WIDTH);
			maskPixels[i]=new int[CON_WIDTH * CON_HEIGHT];
			PixelGrabber pg2=new PixelGrabber(maskIm[i],0,0,CON_WIDTH,CON_HEIGHT,
					maskPixels[i],0,CON_WIDTH);
			try {
				pg.grabPixels();
				pg2.grabPixels();
				} catch (Exception e) {
					System.out.println("Error: " + e);
					};
			}
		System.out.println("Grabbed pixels from controller and mask images.");
		selPixels=new int[CON_WIDTH * CON_HEIGHT];
		PixelGrabber pg=new PixelGrabber(selIm,0,0,CON_WIDTH,CON_HEIGHT,
				selPixels,0,CON_WIDTH);
		try {
			pg.grabPixels();
			} catch (Exception e) {
				System.out.println("Error: " +e);
				};
		System.out.println("Grabbed pixels from selecter image.");
		// now merge the alpha channel info from the mask images into the base images
		for (int i=0; i<4; i++) {
			for (int j=0; j< CON_WIDTH * CON_HEIGHT; j++) {
				conPixels[i][j]=(conPixels[i][j] & 0xffffff ) + 
						((maskPixels[i][j] & 0xff) << 24 );
				};
			};
		System.out.println("Merged alpha channel from masks into base images.");
		};
		
	public void setButtons(TourMap.Navigator navi, boolean waiting) {
		// set up the buttons for a particular node.
		// first, create an array which says which image to take pixels from,
		//    according to which button area we are in.
		int[] selArray=new int[10];
		selArray[0]=0; // always draw the central ring from image 1.
		for (int i=0; i<8; i++) {
			// now set the array for each of the buttons.
			if (navi.canView((byte)i)){
				if (navi.canWalk((byte)i)) {
					selArray[i+1]=3;  // paint from the 'can walk' picture.
				} else {
					selArray[i+1]=2;  // paint from the 'can't walk' picture.
					};
			} else {
				selArray[i+1]=0; // paint from the no buttons picture.
				};
			};
		selArray[9]= (waiting) ? 1 : 0; // are we waiting for something?
		
		System.out.print("SelArray is: ");
		for (int i=0; i<10; i++) {
			System.out.print(selArray[i]+", ");
			};
		System.out.println();
		
		// now scan the selecter pixels, and substitute pixels from one of the
		// four base images according to the selecter array.
		int sel;
		int blue;
		int renPixel;
		int[] renPixels=new int[CON_WIDTH * CON_HEIGHT];
		for (int i=0; i < CON_WIDTH * CON_HEIGHT; i++) {
			blue=selPixels[i] & 0xff; // the blue channel of the selecter.
			if (blue==255) {
				renPixel=0; //transparent pixel
			} else {
				renPixel=conPixels[selArray[(int)blue/20]][i];
				};
		//	System.out.print(selPixels[i]+",");
		//	if (i%20==0) System.out.println();
			renPixels[i]=renPixel ; // add in the alpha channel.
			};
		renIm=createImage(new MemoryImageSource(CON_WIDTH,CON_HEIGHT,
				renPixels,0,CON_WIDTH));
		};
		
	public void paint(Graphics g) {
		// paint the controller.
		g.drawImage(renIm,x,y,tour);
		}
		
	public void mouseClicked(MouseEvent me) {
		// the mouse has been clicked.
		// first check if the click was near the controller.
		if (enabled == false) return;
		if ((me.getX() < x) | (me.getY() < y) | 
				(me.getX() >= x + CON_WIDTH) | (me.getY() >= y + CON_HEIGHT) )
			return;
		// now use the selecter image to work out which button was clicked.
		int selPix=selPixels[(me.getX() - x) + (me.getY() - y) * CON_WIDTH];
		int blue=selPix & 0xff;
		if ((blue < 20) | (blue > 160)) return; // not on a button.
		int button=(blue/20)-1;
		// now move  the tour to a new node.
		tour.move((byte)button);
		};
		
	public void mouseMoved(MouseEvent me) {
		// the mouse was moved. find out where.
		int button;
		if ((enabled == false) | 
				((me.getX() < x) | (me.getY() < y) | 
				(me.getX() >= x + CON_WIDTH) | (me.getY() >= y + CON_HEIGHT) )) {
			button=8;
		} else {
			// now use the selecter image to work out which button was clicked.
			int selPix=selPixels[(me.getX() - x) + (me.getY() - y) * CON_WIDTH];
			int blue=selPix & 0xff;
			if ((blue < 20) | (blue > 160)) {
				button=8;
			} else {
				button=(blue/20)-1;
				};
			};
		// now show the preview image.
		if (button != lastButtonHovered) {
			enabled=false;
			tour.setPreview((byte)button);
			enabled=true;
			};
		lastButtonHovered=button;
		}
	
	public void setEnable(boolean en) {
		enabled=en;
		};
	}; // end of class Tour.Controller

}; //  end of class Tour.


class TourView {
	// this class defines a single view from a TourNode.
	public Image[] images;	// large and small images for this view
	public String comment;	// text comment to be shown when looking at this view
	public TourNode walkTo;	// the node you can walk to along this view, or null.
	public byte walkDir;	// the direction you end up facing when walking to
				// the above node.

	public TourView(TourNode walk, byte dir, String com) {
		// construct with a given walkto, dirn, and comment.
		images=new Image[3];
		walkTo=walk;
		walkDir=dir;
		comment=com;
		};

	};

class TourNode {
	// this class represents a point on the TourMap, from which you can see
	// up to 8 views, and walk to other TourNodes.
	TourView[] views;	// the views from here. (numbered from 0 to 7
				// clockwise.)

	public TourNode() {
		views= new TourView[8];
		};
	
	public TourView getView(byte dir) {
		// return the view in a given direction.
		return views[dir];
		};

	public void setView(TourView view, byte dir) {
		// set the view in a given dirn.
		views[dir]=view;
		};
	};

class TourMap {
	// this class holds the map of a whole tour, consisting of a number of
	// linked TourNode s.
	int numNodes;		// number of nodes in the tour.
	TourNode[] nodeList;	// all the TourNode objects in the tour.
	TourNode firstNode;	// the first node in the tour.
	byte firstDir;		// initial view direction.
	
	void readFile(InputStream is) {
		// read in a data file with a list of map nodes.
		String line;
		TourNode curNode=null;
		byte curDir=0;
		TourView curView=null;
		String walkStr;
		TourNode walkNode=null;
		byte walkDir=(byte)255;
		String comment;
		String nodeComment="";
		boolean extComment=false; // an extended comment over more than one line.
		
		try {
			BufferedReader br = new BufferedReader(new InputStreamReader(is));
				//  convert input stream to a buffered reader.
			numNodes=0;firstNode=null;firstDir=-1;
			while ((line = br.readLine()) != null) {
				// read in the global parameters.
				if (line.startsWith("startMap")) break; // end of global parameters.
				if (line.startsWith("numNodes")) {
					numNodes=Integer.parseInt(line.substring(9));
					nodeList=new TourNode[numNodes+1];	// set up node array.
					for (int i=1; i<=numNodes; i++) // fill array with empty TourNodes.
						nodeList[i]=new TourNode();
					};
				if (line.startsWith("firstNode")) 
					firstNode=nodeList[Integer.parseInt(line.substring(10))];
				if (line.startsWith("firstView"))
					firstDir=(byte)Integer.parseInt(line.substring(10));
				};
			System.out.println("Read global parameters:");
			System.out.println("numNodes = " + numNodes);
			System.out.println("firstNode is " + firstNode);
			System.out.println("firstView is " + firstDir);
			// having read the global parameters, now read in the node data.
			while ((line = br.readLine()) != null) {
				if (line.startsWith("n")) {
					int mark1=line.indexOf(';',0);
					System.out.println();
					System.out.println("Reading node " + line.substring(1,mark1));
					curNode=nodeList[Integer.parseInt(line.substring(1,mark1))];
					nodeComment=line.substring(mark1+1);
					while (nodeComment.endsWith("/")) { // read in an extended comment.
						nodeComment=nodeComment.substring(0,nodeComment.length()-1);
						if ((line= br.readLine()) !=null) {
							nodeComment+=line;
							};
						};
				} else {
					if (line.startsWith(" v")) {
						int mark1=line.indexOf(';',0);				// find the first semicolon.
						int mark2=line.indexOf(';',mark1+1); 	// find the 2nd semicolon.
						curDir=(byte)Integer.parseInt(line.substring(2,mark1));
						walkStr=line.substring(mark1+1,mark2);
						if (walkStr.equals("x")) {	// you can't walk along this view
							walkNode=null;
							walkDir=(byte)255;
							}
						else {	// you can, so get the target node and view.
							int mark3=walkStr.indexOf('v');
							walkNode=nodeList[Integer.parseInt(walkStr.substring(1,mark3))];
							walkDir=(byte)Integer.parseInt(walkStr.substring(mark3+1));
							};
						comment=line.substring(mark2+1);
						while (comment.endsWith("/")) { // read in an extended comment.
							comment=comment.substring(0,comment.length()-1);
							if ((line= br.readLine()) !=null) {
								comment+=line;
								};
							};
						if (comment.length() > 0 ) comment+=System.getProperty("line.separator");
						comment+=nodeComment;
						while ((mark1=comment.indexOf("\\")) != -1) { // convert '\'s to newlines.
							comment=comment.substring(0,mark1-1) + System.getProperty("line.separator")
								+ comment.substring(mark1+1,comment.length());
							};
						curView=new TourView(walkNode,walkDir,comment);
						curNode.setView(curView,curDir);
						System.out.println("Read in view no. " + curDir + " as " + curView.toString());
						};
					};
				};
			} catch (IOException ioe) {
				System.out.println(ioe);
				};
			};
				
	int findNodeNo(TourNode node) {
		// find the node number of a given node.
		int nodeNo=-1;
		for (int i = 1; i<= numNodes; i++) {
			if (nodeList[i]==node) nodeNo=i;
			};
		return nodeNo;
		};
	
	public Navigator GetNavigator() {
		return new Navigator();
		};
		
	class Navigator {
		// this class is used to navigate a TourMap - i.e. move from node
		// to node and view to view.
		TourNode curNode;	// the current node.
		byte curDir;		// current view direction on this node.
	
		public Navigator() {
			curNode = firstNode;
			curDir = firstDir;
			};
		
		public TourNode getNode() {
			return curNode;
			};
	
		public int getNodeNo() {
			return findNodeNo(curNode); // this is a method of the enclosing class TourMap.
			};
			
		public byte getViewNo() {
			return curDir;
			};
			
		public boolean canWalk(byte dir) {
			// can you walk this way? N.B. that dir is relative to the
			// current direction. 0 is ahead, 2 is right, 4 is backwards
			// 6 is left etc.
			if (getView(dir) == null) {
				return false;
			} else {
				return (getView(dir).walkTo != null);
				};
			};
	
		public boolean canView(byte dir) {
			// can you view this direction?
			if (dir > 7) return false;
			return (getView(dir) != null);
			};
			
		public void turn(byte dir) {
			// turn to face the given direction
			if (canView(dir)) {
				curDir+=dir;
				curDir%=8;
				};
			};
	
		public void walk(byte dir) {
			// walk in the given direction.
			if (canWalk(dir)) {
				TourNode newNode=getView(dir).walkTo;
				curDir=getView(dir).walkDir;
				curNode=newNode;
				};
			};
		
		public TourView getView(byte dir) {
			// get the view in the given dirn.
			return curNode.getView((byte)((int)(curDir + dir) % 8));
			};
		}; // end of class Navigator
	
	};