import uwcse.graphics.*;
import java.awt.Color;
import java.util.*;
import java.awt.Point;
import javax.swing.JOptionPane;

/**
 * A CaterpillarDisplay displays a Caterpillar that moves constantly
 * in a graphics window. The user can change the direction of motion
 * of the caterpillar via the keyboard <br>
 * 'i' is north <br>
 * 'j' is west <br>
 * 'k' is east <br>
 * 'm' is south <br>
 */

public class CaterpillarDisplay extends GWindowEventAdapter implements CaterpillarConstants
{
    // Game window
    private GWindow window;

    // The caterpillar
    private Caterpillar cp;

    // Direction of motion given by the player
    private int dirFromKeyboard;

    // Do we have a keyboard event
    private boolean isKeyboardEventNew = false;


    /**
     * Construct a CaterpillarDisplay
     */
    public CaterpillarDisplay()
    {
        // Graphics window
        window = new GWindow("Caterpillar game",WINDOW_WIDTH,WINDOW_HEIGHT);
        window.setExitOnClose();
        // Send all events to this CaterpillarDisplay
        window.addEventHandler(this);
        // Initialize the display
        initializeGame();
    }

    /**
     * Initialize the display
     */
    private void initializeGame()
    {
        // No keyboard event yet
        isKeyboardEventNew = false;

        // Background
        Rectangle background = new Rectangle(0,0,window.getWindowWidth(),window.getWindowHeight(),
        Color.green,true);
        window.add(background);

        // Create the caterpillar
        cp = new Caterpillar(window);

        // start timer events
        window.startTimerEvents(ANIMATION_PERIOD);
    }

    /**
     * Move the caterpillar within the graphics window every time the timer
     * fires an event
     */
    public void timerExpired(GWindowEvent we)
    {
        // Did we get a new direction from the user?
        if (isKeyboardEventNew)
        {
            isKeyboardEventNew = false;
            cp.move(dirFromKeyboard);
        }
        else
            cp.move();
    }

    /**
     * Move the caterpillar according to the selection of the user
     * i: NORTH, j: WEST, k: EAST, m: SOUTH
     */
    public void keyPressed(GWindowEvent e)
    {
        switch(Character.toLowerCase(e.getKey()))
        {
            case 'i':
                dirFromKeyboard = NORTH;
                break;
            case 'j':
                dirFromKeyboard = WEST;
                break;
            case 'k':
                dirFromKeyboard = EAST;
                break;
            case 'm':
                dirFromKeyboard = SOUTH;
                break;
            default:
                return;
        }

        // new keyboard event
        isKeyboardEventNew = true;
    }


    /**
     * If you are not using BlueJ
     */
    public static void main(String[] args)
    {
        CaterpillarDisplay g = new CaterpillarDisplay();
    }
}