let v;
var targetDiameter = 12;
function setup() {
  pixelDensity(1);
  createCanvas(1000, 1000);
  v = new Vehicle(width / 2, height / 2);
  target = createVector(200, 200);
}

function draw() {
  background(51);

  // Draw an ellipse at the mouse position
  fill(127);
  stroke(200);
  strokeWeight(2);
  ellipse(target.x, target.y, targetDiameter, targetDiameter);

  // Call the appropriate steering behaviors for our agents
  v.seek(target);
  v.update();
  v.display();
}

function mouseClicked() {
  target = createVector(mouseX, mouseY);
  hex = find_HexCoordinates(100, target);
  console.log("click " + hex.x + " " + hex.y + " " + hex.z);
}
class ThrustList {
  constructor(thrust, time) {
    this.thrust = createVector(thrust);
    this.time = time;
  }

  set(thrust, time) {
    this.thrust.set(thrust);
    this.time = time;
  }
}

class ThrustParams {
  constructor (deltaPosition, deltaVelocity, maxForce, mass) {
    this.deltaPosition = createVector(deltaPosition);
    this.deltaVelocity = createVector(deltaVelocity);
    this.maxForce = maxForce;
    this.mass = mass;
  }
}

class hexmetrics {
  constructor (radius) {
    this.outerRadius = radius;
    this.innerRadius = this.outerradius * sqrt(3)/2; 
  }
 
}   

function find_HexCoordinates (radius, position) {
  this.innerRadius = radius;
  this.outerRadius = this.innerRadius * sqrt(3)/2;
  this.px = position.x - 1000/2;
  this.py = position.y - 1000/2;
  this.x = px / this.innerRadius * 2;
  this.y = -x;
  this.offset = py / this.outerRadius * 3;
  this.x -= offset;
  this.y -= offset;
  this.iX = Math.round(x);
  this.iY = Math.round(y);
  this.iZ = Math.round(-x -y);
  if (iX + iY + iZ != 0) {
    dX = Math.abs(x-iX);
    dY = Math.abs(y-iY);
    dZ = Math.abs(-x -y -iZ);
    if (dX > dY && dX > dZ) {
      iX = -iY -iZ;
    }
    else if (dZ > dY) {
      iZ = -iX -iY;
    }
  }
    
  return createVector(this.iX, this.iY, this.iZ);
}

class Vehicle {
  constructor(x, y){
    this.mass = 1;
    this.orientation = createVector(0,1);
    this.turning_speed = 90;
    this.acceleration = createVector(0, 0);
    this.maxForce = .02;
    this.position = createVector(x, y);
    this.r = 3;
    this.velocity = createVector(0, 0);
    } 

  // Method to update location
  update() {
  // Update velocity
  this.velocity.add(this.acceleration);
  // Limit speed
  this.position.add(this.velocity);
  // Reset accelerationelertion to 0 each cycle
  this.acceleration.mult(0);
}

  applyForce(force) {
    this.acceleration.add(force);
  }

  // A method that calculates a steering force towards a target
  // STEER = DESIRED MINUS VELOCITY
  seek(target) {
    var desired = p5.Vector.sub(target, this.position); // A vector pointing from the location to the target

    if (desired.mag() > targetDiameter){
      this.orientation = desired;
      if (Math.abs(this.velocity.heading() - desired.heading()) > 0.01 && this.velocity.mag() >0.01) {
        this.orientation = this.velocity.copy().mult(-1);
      }

      if ((this.velocity.mag()*this.velocity.mag())/(2*(this.maxForce/this.mass)) > desired.mag()) {
        this.orientation.mult(-1);
      }

      this.applyForce(this.orientation.normalize().mult(this.maxForce/this.mass));
    } else {

    this.velocity = createVector(0,0);
   }
}

  display() {
    // Draw a triangle rotated in the direction of velocity
    var theta = this.orientation.heading() + PI / 2;
    fill(127);
    stroke(200);
    strokeWeight(1);
    push();
    translate(this.position.x, this.position.y);
    rotate(theta);
    beginShape();
    vertex(0, -this.r * 2);
    vertex(-this.r, this.r * 2);
    vertex(this.r, this.r * 2);
    endShape(CLOSE);
    pop();
  }
}

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