let t;
const len = 1000;

function setup() {
  // createCanvas(400, 300);
  createCanvas(window.innerWidth, window.innerHeight);
  noLoop(); // will draw only once
  t = new Turtle(); // getting ready to draw
  // green
  stroke(0, 200, 0);
  strokeWeight(5);
}

function draw() {
  background(240);

  // getting ready
  t.setxy(-len / 2, 0);
  t.right(90);

  // draw Koch line
  koch(5, len);
}

function koch(order, length) {
  // PLACEHOLDER
  t.forward(200);
}

// Don't write underneath this line

class Turtle {
  constructor() {
    this.oldx = int(width / 2);
    this.oldy = int(height / 2);
    this.x = this.oldx;
    this.y = this.oldy;
    this.tcolor = 0;
    this.angle = 0;
    stroke(this.tcolor);
  }

  forward(step) {
    this.x = this.oldx - step * cos(radians(this.angle + 90));
    this.y = this.oldy - step * sin(radians(this.angle + 90));
    line(this.oldx, this.oldy, this.x, this.y);
    this.oldx = this.x;
    this.oldy = this.y;
  }

  back(step) {
    this.x = this.oldx + step * cos(radians(this.angle + 90));
    this.y = this.oldy + step * sin(radians(this.angle + 90));
    line(this.oldx, this.oldy, this.x, this.y);
    this.oldx = this.x;
    this.oldy = this.y;
  }

  home() {
    this.oldx = int(width / 2);
    this.oldy = int(height / 2);
    line(this.oldx, this.oldy, this.x, this.y);
    this.oldx = this.x;
    this.oldy = this.y;
    this.angle = 0.0;
  }

  setx(step) {
    this.x = this.oldx + step;
    this.oldx = this.x;
  }

  sety(step) {
    this.y = this.oldy + step;
    this.oldy = this.y;
  }

  setxy(stepx, stepy) {
    this.x = this.oldx + stepx;
    this.y = this.oldy + stepy;
    this.oldx = this.x;
    this.oldy = this.y;
  }

  left(dangle) {
    this.angle -= dangle;
  }

  right(dangle) {
    this.angle += dangle;
  }

  setheading(nangle) {
    this.angle = nangle;
  }

  pencolor(ncolor) {
    this.tcolor = ncolor;
    stroke(this.tcolor);
  }

  penup() {
    noStroke();
  }

  pendown() {
    stroke(this.tcolor);
  }
}