p1/machine/ElevatorGui.java

// PART OF THE MACHINE SIMULATION. DO NOT CHANGE.

package nachos.machine;

import java.awt.Frame;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Panel;
import java.awt.ScrollPane;
import java.awt.Canvas;

import java.awt.GridLayout;
import java.awt.FlowLayout;
import java.awt.Insets;

import java.awt.Rectangle;
import java.awt.Graphics;
import java.awt.Color;

/**
 * A graphical visualization for the <tt>ElevatorBank</tt> class.
 */
public final class ElevatorGui extends Frame {
    private final static int w=90, h=75;

    private int numFloors, numElevators;
    
    private ElevatorShaft[] elevators;  
    private Floor[] floors;

    private int totalWidth, totalHeight;

    ElevatorGui(int numFloors, int numElevators, int[] numRidersPerFloor) {
	this.numFloors = numFloors;
	this.numElevators = numElevators;

	totalWidth = w*(numElevators+1);
	totalHeight = h*numFloors;

	setTitle("Elevator Bank");

	Panel floorPanel = new Panel(new GridLayout(numFloors, 1, 0, 0));
	
	floors = new Floor[numFloors];
	for (int i=numFloors-1; i>=0; i--) {
	    floors[i] = new Floor(i, numRidersPerFloor[i]);
	    floorPanel.add(floors[i]);
	}

	Panel panel = new Panel(new GridLayout(1, numElevators+1, 0, 0));

	panel.add(floorPanel);

	elevators = new ElevatorShaft[numElevators];
	for (int i=0; i<numElevators; i++) {
	    elevators[i] = new ElevatorShaft(i);
	    panel.add(elevators[i]);
	}

	add(panel);
	pack();

	setVisible(true);

	repaint();
    }

    void openDoors(int elevator) {
	elevators[elevator].openDoors();
    }
    
    void closeDoors(int elevator) {
	elevators[elevator].closeDoors();
    }
    
    void setDirectionDisplay(int elevator, int direction) {
	elevators[elevator].setDirectionDisplay(direction);
    }
    
    void pressUpButton(int floor) {
	floors[floor].pressUpButton();
    }

    void clearUpButton(int floor) {
	floors[floor].clearUpButton();
    }

    void pressDownButton(int floor) {
	floors[floor].pressDownButton();
    }
    
    void clearDownButton(int floor) {
	floors[floor].clearDownButton();
    }

    void enterElevator(int floor, int elevator) {
	floors[floor].removeRider();
	elevators[elevator].addRider();
    }
    
    void pressFloorButton(int floor, int elevator) {
	elevators[elevator].pressFloorButton(floor);
    }
    
    void exitElevator(int floor, int elevator) {
	elevators[elevator].removeRider();
	floors[floor].addRider();
    }
    
    void elevatorMoved(int floor, int elevator) {
	elevators[elevator].elevatorMoved(floor);
    }

    private void paintRider(Graphics g, int x, int y, int r) {
	g.setColor(Color.yellow);
	
	g.fillOval(x-r, y-r, 2*r, 2*r);
	
	g.setColor(Color.black);
	
	g.fillOval(x-r/2, y-r/2, r/3, r/3);
	g.fillOval(x+r/4, y-r/2, r/3, r/3);
	
	g.drawArc(x-r/2, y-r/2, r, r, 210, 120);
    }

    private void paintRiders(Graphics g, int x, int y, int w, int h, int n) {
	int r = 8, t = 20;

	int xn = w/t;
	int yn = h/t;

	int x0 = x + (w-xn*t)/2 + t/2;
	int y0 = y + h - t/2;

	for (int j=0; j<yn; j++) {
	    for (int i=0; i<xn; i++) {
		if (n-- > 0)
		    paintRider(g, x0 + i*t, y0 - j*t, r);
	    }
	}
    }

    private class Floor extends Canvas {
	int floor, numRiders;

	boolean upSet = false;
	boolean downSet = false;

	Floor(int floor, int numRiders) {
	    this.floor = floor;
	    this.numRiders = numRiders;

	    setBackground(Color.black);
	}

	public Dimension getPreferredSize() {
	    return new Dimension(w, h);
	}
    
	public Dimension getMinimumSize() {
	    return getPreferredSize();
	}
    
	public Dimension getMaximumSize() {
	    return getPreferredSize();
	}

	public void repaint() {
	    super.repaint();
	    
	    if (TCB.isNachosThread()) {
		try {
		    Thread.sleep(100);
		}
		catch (InterruptedException e) {
		}
	    }
	}

	void pressUpButton() {
	    if (!upSet) {
		upSet = true;
		repaint();
	    }
	}

	void pressDownButton() {
	    if (!downSet) {
		downSet = true;
		repaint();
	    }
	}

	void clearUpButton() {
	    if (upSet) {
		upSet = false;
		repaint();
	    }
	}

	void clearDownButton() {
	    if (downSet) {
		downSet = false;
		repaint();
	    }
	}	

	void addRider() {
	    numRiders++;

	    repaint();
	}

	void removeRider() {
	    numRiders--;

	    repaint();
	}

	public void paint(Graphics g) {
	    g.setColor(Color.lightGray);
	    g.drawLine(0, 0, w, 0);

	    paintRiders(g, 0, 5, 3*w/4, h-10, numRiders);

	    paintButtons(g);
	}

	private void paintButtons(Graphics g) {
	    int s = 3*w/4;

	    int x1 = s+w/32;
	    int x2 = w-w/32;
	    int y1 = h/8;
	    int y2 = h-h/8;

	    g.setColor(Color.darkGray);
	    g.drawRect(x1, y1, x2-x1, y2-y1);
	    g.setColor(Color.lightGray);
	    g.fillRect(x1+1, y1+1, x2-x1-2, y2-y1-2);

	    int r = Math.min((x2-x1)/3, (y2-y1)/6);
	    int xc = (x1+x2)/2;
	    int yc1 = (y1+y2)/2 - (3*r/2);
	    int yc2 = (y1+y2)/2 + (3*r/2);

	    g.setColor(Color.red);

	    if (floor < numFloors-1) {
		if (upSet)
		    g.fillOval(xc-r, yc1-r, 2*r, 2*r);
		else
		    g.drawOval(xc-r, yc1-r, 2*r, 2*r);
	    }

	    if (floor > 0) {
		if (downSet)
		    g.fillOval(xc-r, yc2-r, 2*r, 2*r);
		else
		    g.drawOval(xc-r, yc2-r, 2*r, 2*r);
	    }
	}  
    }

    private class ElevatorShaft extends Canvas {
	ElevatorShaft(int elevator) {
	    this.elevator = elevator;

	    floorsSet = new boolean[numFloors];
	    for (int i=0; i<numFloors; i++)
		floorsSet[i] = false;

	    setBackground(Color.black);
	}

	public Dimension getPreferredSize() {
	    return new Dimension(w, h*numFloors);
	}
    
	public Dimension getMinimumSize() {
	    return getPreferredSize();
	}
    
	public Dimension getMaximumSize() {
	    return getPreferredSize();
	}

	private void repaintElevator() {
	    repaint(s, h*(numFloors-1-Math.max(floor, prevFloor)), w-2*s, h*2);
	    
	    try {
		Thread.sleep(100);
	    }
	    catch (InterruptedException e) {
	    }
	}

	void openDoors() {
	    doorsOpen = true;

	    repaintElevator();
	}

	void closeDoors() {
	    doorsOpen = false;
	    
	    repaintElevator();
	}

	void setDirectionDisplay(int direction) {
	    this.direction = direction;

	    repaintElevator();
	}

	void pressFloorButton(int floor) {
	    if (!floorsSet[floor]) {
		floorsSet[floor] = true;

		repaintElevator();
	    }
	}

	void elevatorMoved(int floor) {
	    prevFloor = this.floor;
	    this.floor = floor;

	    floorsSet[floor] = false;

	    repaintElevator();
	}

	void addRider() {
	    numRiders++;

	    repaintElevator();
	}

	void removeRider() {
	    numRiders--;

	    repaintElevator();
	}

	public void paint(Graphics g) {
	    g.setColor(Color.lightGray);
	    
	    if (g.hitClip(0, 0, s, h*numFloors)) {
		g.drawLine(0, 0, 0, h*numFloors);
		g.drawLine(s-1, 0, s-1, h*numFloors);
		for (int y=0; y<h*numFloors-s; y+=s)
		    g.drawLine(0, y, s-1, y+s-1);
	    }
		
	    if (g.hitClip(w-s, 0, s, h*numFloors)) {
		g.drawLine(w-s, 0, w-s, h*numFloors);
		g.drawLine(w-1, 0, w-1, h*numFloors);
		for (int y=0; y<h*numFloors-s; y+=s)
		    g.drawLine(w-s, y, w-1, y+s-1);
	    }

	    // rectangle containing direction display area
	    Rectangle d = new Rectangle(s*3/2, h*(numFloors-1-floor),
					w-3*s, w/3-s);

	    // unit of measurement in direction rect (12ux4u)
	    int u = d.width/12;

	    // draw elevator, fill riders
	    Rectangle e = new Rectangle(d.x, d.y+d.height,
					d.width, h-d.height-u);
	    g.drawRect(e.x, e.y, e.width, e.height);
	    paintRiders(g, e.x, e.y, e.width, e.height, numRiders);

	    g.setColor(Color.lightGray);
	    
	    // draw doors...
	    if (doorsOpen) {
		g.drawLine(e.x+2*s, e.y, e.x+2*s, e.y+e.height);
		for (int y=0; y<e.height-2*s; y+=2*s)
		    g.drawLine(e.x, e.y+y, e.x+2*s, e.y+y+2*s);

		g.drawLine(e.x+e.width-2*s, e.y,
			   e.x+e.width-2*s, e.y+e.height);
		for (int y=0; y<e.height-2*s; y+=2*s)
		    g.drawLine(e.x+e.width-2*s, e.y+y, e.x+e.width, e.y+y+2*s);
	    }
	    else {
		for (int x=0; x<e.width; x+=2*s)
		    g.drawLine(e.x+x, e.y, e.x+x, e.y+e.height);
	    }
	    
	    g.setColor(Color.yellow);
	    
	    int[] xUp = { d.x + u*6, d.x + u*8, d.x + u*7 };
	    int[] yUp = { d.y + u*3, d.y + u*3, d.y + u*1 };
		
	    int[] xDown = { d.x + u*4, d.x + u*6, d.x + u*5 };
	    int[] yDown = { d.y + u*1, d.y + u*1, d.y + u*3 };

	    // draw arrows
	    if (direction == ElevatorBank.dirUp)
		g.fillPolygon(xUp, yUp, 3);
	    else
		g.drawPolygon(xUp, yUp, 3);

	    if (direction == ElevatorBank.dirDown)
		g.fillPolygon(xDown, yDown, 3);
	    else
		g.drawPolygon(xDown, yDown, 3);
	}

	private static final int s = 5;
	
	private boolean doorsOpen = false;
	private int floor = 0, prevFloor = 0, numRiders = 0;
	private int direction = ElevatorBank.dirNeither;

	private int elevator;

	private boolean floorsSet[];
    }
}