let h = 700;

let sq = 20;

​

function setup() {

  createCanvas(w, h);

}

​

class Snake {

  constructor(x, y) {

    this.x = x;

    this.y = y;

    this.size = 19;

    this.body = [];

    this.score = 0;

  }

  drawSnake() {

    this.head = [this.x, this.y];

    fill(255, 0, 0);

    rect(this.head[0], this.head[1], this.size, this.size);

    for (let i = 0; i < this.body.length; i++) {

      rect(this.body[i][0], this.body[i][1], this.size, this.size);

    }

  }

  Mvt() {

    if (keyCode === UP_ARROW) {

      this.y -= 20;

    } else if (keyCode === DOWN_ARROW) {

      this.y += 20;

    } else if (keyCode === RIGHT_ARROW) {

      this.x += 20;

    } else if (keyCode === LEFT_ARROW) {

      this.x -= 20;

    }

    if (this.x > w) {

      this.x = 0;

    }

    if (this.x < 0) {

      this.x = w;

    }

    if (this.y > h) {

      this.y = 0;

    }

    if (this.y < 0) {

      this.y = h;

    }

  }

  eatFood() {

    if (this.x === food.x && this.y === food.y) {

      this.score += 1;

      for (let i = 0; i < this.body; i++) {

      }

      return true;

    } else {

      return false;

    }

  }

  bodyGenerator() {

    this.eatFood();

    this.body.push([this.head[0], this.head[1]]);

    if (this.body.length > this.score) {

      this.body.splice(0, 1);

    }

  }

  eatSelf() {

    if (this.body.lentgh >= 1){

    for (let i = 1; i < this.body.length; i++) {

      if (this.head[0] === this.body[i][0] && this.head[1] === this.body[i][1]) {

        this.body.splice(0, this.body.length - 1);

        }

      }

    }

  }

}

​

class Food {

  constructor() {

    this.x = this.x = Math.floor((Math.random() * w) / 20) * 20;

    this.y = this.y = Math.floor((Math.random() * h) / 20) * 20;

    this.color = 255;

    this.size = 19;

  }

  drawFood() {

    fill(0, 255, 0);

    rect(this.x, this.y, this.size, this.size);

  }

  spawn() {

    if (snake.x === this.x && snake.y === this.y) {

      let xc = Math.random();

      let yc = Math.random();

      this.x = Math.floor((xc * w) / 20) * 20;

      this.y = Math.floor((yc * h) / 20) * 20;

    }

  }

}

​

let snake = new Snake(200, 200);

let food = new Food();

​

function draw() {

  background(0);

  frameRate(6);

  stroke(255);

  for (let x = sq; x < w; x = x + sq) {

    line(x, 0, x, h);

  }

  for (let y = sq; y < h; y = y + sq) {

    line(0, y, h, y);

  }

  snake.drawSnake();

  snake.Mvt();

  snake.bodyGenerator();

  snake.eatSelf();

  food.drawFood();

  food.spawn();

}

​