const serial = new p5.WebSerial();

let portButton;

let inData;

let outData;

// let digitalread;

var s;

var scl = 20;

var food;

​

function Snake() {

​

  this.x = 0;

  this.y = 0;

  this.xspeed = 2;

  this.yspeed = 0;

  this.total = 0;

  this.tail = [];

  this.dir = function(x, y) {

    this.xspeed = x;

    this.yspeed = y;

  }

  this.eat = function(pos) {

    var d = dist(this.x, this.y, pos.x, pos.y);

    if (d < 20) {

      this.total ++;

      return true;

    } else {

      return false;

    }

  }

  this.update = function() {

    if (this.total === this.tail.length) {

      for (var i=0; i < this.tail.length-1; i++) {

      this.tail[i] = this.tail[i+1]; 

    }

    }

    this.tail[this.total-1] = createVector(this.x, this.y);

    this.x = this.x + this.xspeed * 5; // Move the snake in steps of 10 pixels

    this.y = this.y + this.yspeed * 5;

    // Wrap snake position when it goes off the canvas

    this.x = (this.x + this.xspeed*scl);

    this.y = (this.y + this.yspeed*scl);

    this.x = constrain(this.x, 0, width-scl);

    this.y = constrain(this.y, 0, height-scl);

  }

  this.death = function() {

    for (var i=0; i<this.tail.length; i++){

      var pos = this.tail[i];

      var d = dist(this.x, this.y, pos.x, pos.y);

      if (d<1) {

        console.log("Starting Over!")

        fill(255, 0, 0);

        textSize(150);

        text("GAME\nOVER!", 100, 300);

        this.total = 0;

        this.tail = [];

      }

    }

  }

  this.show = function() {

    fill(255);

    for (var i=0; i < this.tail.length; i++) {

      rect(this.tail[i].x, this.tail[i].y, scl, scl) 

    }

    fill(255);

    for (var i=0; i<this.total; i++) {

      rect(this.tail[i].x, this.tail[i].y, scl, scl)

    }

    rect(this.x, this.y, scl, scl);

  }

​

}

​

function setup() {

  createCanvas(600, 600);

  s = new Snake();

  frameRate(5); // Set the frame rate to make the game run smoother

  pickLocation();

  if (!navigator.serial) {

    alert("WebSerial is not supported. Try Chrome.");

  }

  // First time you connect, create button to identify port

  if (askForPort) {

    makePortButton();

  } else {

    serial.getPorts(); // Skip the button, use port from last time

  }

  serial.on("portavailable", openPort);

  serial.on("data", serialEvent);

}

​

function pickLocation() {

  var cols = floor(width/scl);

  var rows = floor(height/scl);

  food = createVector(floor(random(cols)), floor(random(rows)));

  food.mult(scl);

}

​

function draw() {

  if (inData) {

    let x = inData[0];

    // console.log(x);

    if (x == 0) {

    s.dir(0, -1);

  } else if (x == 1) {

    s.dir(0, 1);

  } else if (x == 3) {

    s.dir(-1, 0);

  } else if (x == 2) {

    s.dir(1, 0);

  }

    background(0);

    s.death();

    s.update();

    s.show();

    fill(255, 0, 0);

    rect(food.x, food.y, scl, scl);

    if (s.eat(food)) {

      pickLocation();

    }

     }

}

​

​

function serialEvent() {

  // Read a string from the serial port until you get carriage return and newline:

  let inString = serial.readStringUntil("\r\n");

  // console.log(inString);

  // Check to see that there's actually a string there:

  if (inString) {

    inData = split(inString, ",");

  }

}

​

function openPort() {

  serial.open();

  if (portButton) portButton.hide();

}

​

function makePortButton() {

  // Create and position a port chooser button:

  portButton = createButton("Choose Port");

  portButton.position(10, 10);

  // Give the port button a mousepressed handler:

  portButton.mousePressed(() => serial.requestPort());

​

}