Player.java

import greenfoot.*; // import every greefoot function, object and more

public class Player extends Actor
{
    private int health = 800;
    private int moveSteps = 4;
    
    // position datas
    private int groundLevel;
    private int yCord;
    private int xCord = 200;
    
    // jump flags
    private boolean jumpedUp = false;
    private boolean jumpFinished = true;
    private boolean canDoubleJump = true;
    private boolean spacePreviouslyDown = false;
    
    // jump movement datas
    private int initialJumpSpeed = 16;
    private int doubleJumpSpeed = 14;
    private double ySpeed = 0;
    private double gravity = 0.7;
    private double maxFallSpeed = 10;
        
    private int steppingIndex = 1;
    
    public Player() {
        GreenfootImage image = new GreenfootImage("./images/knight.png");
        this.setImage(image);
        this.groundLevel = MapManager.getHeight() - image.getHeight()/2 - MapManager.getGroundHeight();
        this.yCord = this.groundLevel;
        this.showHealth();
    }

    public int getXCord() {
        return xCord;
    }

    public int getYCord() {
        return yCord;
    }
    
    public void act() {
        this.stepping();
        this.moving();
        this.jumping();
        this.damage();
        this.heal();
    }
    
    /**
     * Change image of the player to create an nice setpping effect
     */
    private void stepping() {
        if (this.steppingIndex < 9)
        {
            this.steppingIndex = this.steppingIndex + 1;
        } else {
            this.steppingIndex = 0;
        }
        this.setImage("./images/knight_" + this.steppingIndex + ".png");
    }

    /**
     * Handle all methods for the jumping feature
     */
    private void jumping() {
        this.handleJumpInput();
        this.applyGravity();
        this.applyMovement();
        this.checkGround();
    }
    
    private void handleJumpInput() {
        boolean spaceNowDown = Greenfoot.isKeyDown("space");
    
        // activate jump motion
        if (spaceNowDown && !this.spacePreviouslyDown) {
            if (this.jumpFinished) { // first jump
                this.ySpeed = -this.initialJumpSpeed;
                this.jumpFinished = false;
                this.canDoubleJump = true;
            } else if (this.canDoubleJump) { // second jump
                this.ySpeed = -this.doubleJumpSpeed;
                this.canDoubleJump = false;
            }
        }
    
        this.spacePreviouslyDown = spaceNowDown;
    }
    
    /**
     * Add gravity to the jump
     */
    private void applyGravity() {
        this.ySpeed += this.gravity;
        if (this.ySpeed > this.maxFallSpeed) {
            this.ySpeed = this.maxFallSpeed;
        }
    }
    
    /**
     * The acctully jump 
     */
    private void applyMovement() {
        this.yCord += (int) this.ySpeed;
        this.setLocation(this.xCord, this.yCord);
    }
    
    /**
     * Reset datas when player is on ground
     */
    private void checkGround() {
        if (this.yCord >= this.groundLevel) {
            this.yCord = this.groundLevel;
            setLocation(this.xCord, this.yCord);
            
            this.ySpeed = 0;
            this.jumpFinished = true;
            this.canDoubleJump = true;
        }
    }

    private void moving()
    {
        // move left
        if (Greenfoot.isKeyDown("left")) {
            this.xCord = this.xCord - this.moveSteps;
            this.setLocation(this.xCord, this.yCord);
        }
        
        // move right
        if (Greenfoot.isKeyDown("right")) {
           this.xCord = this.xCord + this.moveSteps;
           this.setLocation(this.xCord, this.yCord); 
        }
    }
    
    public void damage() {
        if (this.isTouching(Enemy.class)) {
            Enemy enemy = (Enemy) getOneIntersectingObject(Enemy.class);
            this.health -= enemy.getDamage();
            
            // stop game when player has no health
            if (this.health <= 0) {
                GameManager.stop();
                return;
            }
            
            // place medi kit
            if (this.health == 100) {
                this.placeMediKit();
            }
            
            this.showHealth();
        }
    }
    
    private void showHealth() {
        MapManager.showText("♥️" + this.health, 80, 30);
    }
    
    private void placeMediKit() {
        if (this.yCord == this.groundLevel) {
            MediKit mediKit = new MediKit();
            MapManager.currentMap.addObject(mediKit, Greenfoot.getRandomNumber(MapManager.getWidth()) + 10, this.yCord - 200);
        }
    }
    
    /**
     * Add health
     */
    private void heal() {
        if (this.isTouching(MediKit.class)) {
            MediKit mediKit = (MediKit) getOneIntersectingObject(MediKit.class);
            this.health += mediKit.getHealLevel();
            this.showHealth();
            MapManager.currentMap.removeObject(mediKit);
        }
    }
}