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/**
 * Write a description of class LunarLander here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */

//Functionality
import javax.swing.JFrame;      // window functionality
import java.awt.Color;          // RGB color stuff

import javax.swing.Timer;       // import timer functionality
import java.awt.event.*;        // functionality for the event fired by the timer

import java.awt.*;              // Graphics stuff from the AWT library, e.g. Graphics
import javax.swing.*;           // Graphics stuff from the Swing library, e.g. JLabel
import java.awt.image.BufferedImage; // Graphics drawing canvas
import java.awt.event.KeyEvent;
import java.util.Random;
public class LunarLander extends JFrame{

    // The Java window
    private static JFrame window;
    
    // Graphics "Handle"
    private static Graphics gr; 
    
    // Image Storage
    private static Image theBackground; // Background Image
    private static Image theLander; // PNG of the Lunar Lander
    private static Image theBang; // Animated Explosion
    public static Random randomGen= new Random();
    
    private static int landerX = randomGen.nextInt(800 - 50), landerY = 50; // Starting position of the lander
    private static boolean  explosion=false; // Sets explosion to false
    public static int speedY = 0;
    public static int speedX = 0;
    public static double speedStopping = 1;
    public static int speedAccelerating = 2;
    public static int topLandingSpeed = 5;
    
    
    // Main Method, Create window
    public static void main(String[] args) {
        
        //Window Setup
        window = new JFrame(); // Renames the new window
        
        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // Sets the X to close
        window.setTitle("Moon Lander, Can you be the first man on the moon!"); // Title Name
        window.setSize(800, 600); // Window Size
        window.setResizable(true); // Disables resizable window
        window.setLocationRelativeTo(null); // Sets location to top of the screen
        
        BufferedImage canvas=new BufferedImage(800,600,BufferedImage.TYPE_INT_ARGB); // Creates A Canvas
        gr=canvas.getGraphics(); // Creates handle for drawing on the canvas
        JLabel label=new JLabel(new ImageIcon(canvas)); // Creates label to draw on
        window.add(label);
        
        window.setVisible(true); // Displays above
        
        //Loading Images
        theBackground = GameImage.loadImage("Images//Background.png"); // Loads background
        theLander = GameImage.loadImage("Images//LunarLander.png"); // Loads lander
        theBang = GameImage.loadImage("Images//explosion.gif"); // Loads Explosion
             
        GameKeyboard.initialise(); // Starts keyboard input
        
        
        
        //Timer Setup
        ActionListener taskPerformer = new ActionListener()
            {
                public void actionPerformed(ActionEvent evt) // Calls the actionPerformed() method
                {
                    doTimerAction();
                }    
            };
        Timer ScreenTimer = new Timer(75, taskPerformer); // Creates Timer
        ScreenTimer.start(); // Starts Timer
    }
    
    // Method to draw all needed images, then timer resets to display on the screen
    private static void doTimerAction() {
        
        gr.drawImage(theBackground, 0, 0, null); // Overwrites everything with the background image
        
        // User Instructions
        gr.setColor( Color.red );  // Sets colour red
        gr.setFont(new Font("Arial", Font.BOLD, 16)); // Sets font
        gr.drawString("Arrow keys to move, land on the platform to win", 200,200); // Output and location
        

        
        // Get keys pressed from the keyboard
        char key= GameKeyboard.getKey();
        int specialKey=GameKeyboard.getSpecialKey();
        
        
        //Keyboard Binding
        
        
        if (landerY >= 500){
            gr.drawImage(theBang, landerX, landerY, null);
            gr.setColor( Color.red );  // Sets colour red
        gr.setFont(new Font("Arial", Font.BOLD, 16)); // Sets font
        gr.drawString("You have crashed! Restart game!", 200,400);
        }else{  
            
            
        if (specialKey == 38){
            speedY -= speedAccelerating;
        }else{ 
            speedY += speedStopping;
        }  
        
        if (specialKey == 37){
            speedX -= speedAccelerating;
        }else{
            speedX += speedStopping;
        }
            
        if (specialKey == 39){
            speedX += speedAccelerating;
        }else{
            speedX -= speedStopping;
        }
        
        landerX += speedX;
        landerY += speedY;
        

        

        gr.setColor( Color.red );  // Sets colour red
        gr.setFont(new Font("Arial", Font.BOLD, 16)); // Sets font
        gr.drawString("speedX" + speedX + "speedY" + speedY + "speedAccelerating" +speedAccelerating + "speedStopping" + speedStopping + "landerY" + landerY + "landerX" + landerX, 200,400);
        gr.drawImage(theLander, landerX, landerY, null); // Draws lander and its position
        
    }    
    window.repaint();  // Re paints everything onto the screen
    }    
}

/* 
 * This class implements a simple keyboard event dispatcher. Normally a Java application attaches so
 * called 'KeyListeners' to individual objects such as text input fields. In a game, however, we want
 * all parts of the game window to respond to keyboard inputs without having to click on them first.
 * We also don't want the repetitive task of attaching a 'KeyListenr' to each and every object that
 * may appear in the game.
 * The drawback of this apprach is that it is now tricky to use a standard text input field - alas,
 * that is probably not really what we want anyway.
 * 
 * USAGE:
 * ======
 * In the game class just add this line:
 *         GameKeyboard.initialise();
 *         
 * You can then interrogate two variables: 'key' and 'specialKey' like this:
 *         if(GameKeyboard.getKey() == 'q') {  ...
 *         if(GameKeyboard.getSpecialKey() == 38) { // 'up' arrow key is 38, down is 40, ...
 */


import java.awt.*;              // Graphics stuff from the AWT library, her for the KeyEventDispatcher
import java.awt.event.*;        // Event handler, here for keyboard events

public class GameKeyboard implements KeyEventDispatcher {

    // The variable 'key' and 'specialKey' are private but can be accessed via the public
    // 'get' methods 'getKey()' and 'getSpecialKey()'. These are coded below.
    // These can be interrogated from the main application
    private static char key=' ';
    private static int  specialKey=0;

    // This constant is public so that other classes can check if a key has been pressed.
    // e.g.  if(kbd.getKey() != kbd.NONE) {...
    public final int NONE=0;

    private static GameKeyboard kbd;

    // Attach a keyboard focus manager to the keyboard event dispatcher
    // Don't worry if you don't understand this. Just leave it as it is.
    public GameKeyboard() {
        KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
        manager.addKeyEventDispatcher( this );    
    }

    // This is the method that actually checks the keyboard for key strokes and sets the two
    // private variables of this class ('key' and 'specialKey') to its values accordingly.
    public boolean dispatchKeyEvent(KeyEvent e) {


        // To start with, let's reset both variables
        key= NONE;
        specialKey= NONE;

        // Read the special keys (e.g. arrow keys, Shift, Alt, ...)
        specialKey= e.getKeyCode();

        // Only if no special character was pressed, check for normal keys, otherwise you
        // get the scan codes of the special keys
        if(specialKey == NONE) {
            key = e.getKeyChar();
        }

        // If a key is going up, reset the two variables.
        if (e.getID() == KeyEvent.KEY_RELEASED) {
            key= NONE;
            specialKey= NONE;
        } 

        return false;
    }

    public static void initialise() {
        GameKeyboard kbd= new GameKeyboard();
    }

    public static char getKey() {
        return key;
    }

    public static int getSpecialKey() {
        return specialKey;
    }
    
}

/*
 * This is a very simple class that encapsulates the loading
 * of images only.
 * 
 * Access from other classes: 
 *     Image myImg = GameImage.loadImage("C://MyImage.gif");
 */

import java.awt.*;              // Graphics stuff from the AWT library, here: Image
import java.io.File;            // File I/O functionality (for loading an image)
import javax.swing.ImageIcon;   // All images are used as "icons"



public class GameImage
{
    public static Image loadImage(String imagePathName) {
        
        // All images are loades as "icons"
        ImageIcon i = null;
        
        // Try to load the image
        File f = new File(imagePathName);
        
        
        if(f.exists()) {  // Success. Assign the image to the "icon"
            i = new ImageIcon(imagePathName);
        }
        else {           // Oops! something is wrong.
            System.out.println("\nCould not find this image: "+imagePathName+"\nAre file name and/or path to the file correct?");            
            System.exit(0);
        }
        
        // Done. Either return the image or "null"
        return i.getImage();
        
    } // End of loadImages method

}