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package keyEventlearning;

import javafx.animation.*;
import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
import javafx.util.Duration;

import java.util.ArrayList;
import java.util.List;


public class first extends Application {
    private List<Rectangle> snakeBody = new ArrayList<>();
    private Pane sp = new Pane();
    private dir direction = dir.right;
    private boolean running = false;
    private Rectangle snake = new Rectangle(0, 0, 25, 25);
    private Rectangle food = new Rectangle(25, 25);
    private Timeline timeline = new Timeline();
    private String s;
    private Group g = new Group();


    public enum dir {
        right, left, up, down

    }

    private void createFood() {
        food.setFill(Color.RED);
        food.setTranslateX((int) (Math.random() * (475)) / 25 * 25);
        food.setTranslateY((int) (Math.random() * (475)) / 25 * 25);
    }

    public Rectangle r() {
        return new Rectangle(snake.getX(), snake.getY(), 25, 25);
    }


    private void createSnake() {
        snake.setFill(Color.BLUE);
        snake.setX((int) (Math.random() * (250)) / 25 * 25);
        snake.setY((int) (Math.random() * (250)) / 25 * 25);
        snakeBody.add(0, snake);
        new AnimationTimer() {
            private long lastUpdate = 0;

            public void handle(long now) {
                if (now - lastUpdate >= 280000000) {


                    if (snake.getX() == food.getTranslateX() && snake.getY() == food.getTranslateY()) {
                        createFood();
                        snakeBody.add(r());
                        snakeBody.get(snakeBody.size()-1).setFill(Color.BLUE);
                        g.getChildren().addAll(snakeBody.get(snakeBody.size()-1));
                    }
                    if (running) {
                        switch (direction) {
                            case right:
                                if(snakeBody.size() > 1) {
                                    snakeBody.get(snakeBody.size()-1).setX(snake.getX());
                                    snakeBody.get(snakeBody.size()-1).setY(snake.getY());

                                }
                                    snake.setY(snake.getY());
                                    snake.setX(snake.getX()+25);

                                break;
                            case left:
                                if(snakeBody.size() > 1) {
                                snakeBody.get(snakeBody.size()-1).setX(snake.getX());
                                snakeBody.get(snakeBody.size()-1).setY(snake.getY());

                            }
                                    snake.setY(snake.getY());
                                    snake.setX(snake.getX()-25);

                                break;
                            case up:
                                if(snakeBody.size() > 1) {
                                    snakeBody.get(snakeBody.size()-1).setX(snake.getX());
                                    snakeBody.get(snakeBody.size()-1).setY(snake.getY());

                                }
                                    snake.setY(snake.getY()+25);
                                    snake.setX(snake.getX());

                                break;
                            case down:
                                if(snakeBody.size() > 1) {
                                    snakeBody.get(snakeBody.size()-1).setX(snake.getX());
                                    snakeBody.get(snakeBody.size()-1).setY(snake.getY());

                                }
                                    snake.setY(snake.getY()-25);
                                    snake.setX(snake.getX());
                                break;
                        }
                    }
                    lastUpdate = now;
                }
            }
        }.start();

    }

    private void startGame() {
        createFood();
        createSnake();
        running = false;
    }


    public static void main(String args) {
        launch(args);
    }

    public void start(Stage primaryStage) {
        sp.setPrefSize(500, 500);
        g.getChildren().addAll(sp);
        sp.setPrefSize(500, 500);
        sp.getChildren().addAll(food,snake);
        Scene scene = new Scene(g, Color.FLORALWHITE);
        scene.setOnKeyPressed(e -> {
            s = e.getCode().toString();
            running = false;
        });
        KeyFrame kf = new KeyFrame(new Duration(20), e -> {


            if (!running) {
                switch (s) {
                    case "W":
                        if (direction != dir.up) {
                            direction = dir.down;
                            running = true;
                            break;
                        }
                    case "S":
                        if (direction != dir.down) {
                            direction = dir.up;
                            running = true;
                            break;
                        }
                    case "A":
                        if (direction != dir.right) {
                            direction = dir.left;
                            running = true;
                            break;
                        }
                    case "D":
                        if (direction != dir.left) {
                            direction = dir.right;
                            running = true;
                            break;
                        }
                }
            }


        });
        timeline.getKeyFrames().add(kf);
        timeline.setCycleCount(Animation.INDEFINITE);
        timeline.play();


        startGame();
        primaryStage.setScene(scene);
        primaryStage.setTitle("Hello");
        primaryStage.show();

    }
}