Zone[] zones;
boolean moveY; // true when user is moving along the y axis (using w and s keys)
String direction; // to tell showDirections which kind of arrow to draw

int numZones;

void setup()
{
  size(640, 480);
  background(255);
  numZones = 15;

  zones = new Zone[numZones];

  //populating that array
  for (int i=0; i<numZones; i++) {
    zones[i] = new Zone(random(width), random(height), int(random(50))+20);
  }
  
  moveY = true; //assume we are moving forward initially
  

  //x = width/2+track_x; //x position on stage
  //y = height/2+track_y; //y position on stage
}

void loop()
{
  //static stuff
  background(255);  //comment this out to see cool stuff
  
  // draw out arrow  
  showDirection(direction);
  
  ellipseMode(CENTER_RADIUS);
  for(int i=0; i<numZones; i++) {
    zones[i].update();
  }
  
  stroke(0);
  fill(0);
  rectMode(CENTER_RADIUS);
  rect(width/2, height/2, 5, 5); //draw out a rectangle at center -- represents the user
  
  keyPressed();  

}

//handles the key stuff, moving forward, backward, or turning left or right
void keyPressed() 
{
  if (key == 'a') {
    for(int n=0; n<numZones; n++) {
      zones[n].i-=radians(2);
   }
    direction="LEFT";
    moveY=false;
  }

  if (key == 'd') {
    for(int n=0; n<numZones; n++) {
      zones[n].i+=radians(2);
   }
    direction="RIGHT";
    moveY=false;
  }
  if (key == 'w') {
    for(int n=0; n<numZones; n++) {
      zones[n].y+=2;
    }
    direction="FORWARDS";
    moveY=true;
  }
  if (key == 's') {
    for(int n=0; n<numZones; n++) {
      zones[n].y-=2;
    }
    direction="BACKWARDS";
    moveY=true;
  }

}

//draws out helper arrows that signal current direction / rotation
void showDirection(String dir) 
{
  push();
  translate((width/2)-30, (height/2)-60);
  if (dir=="NONE") {
    rect(10, 10, 10, 10);
  }
  if (dir=="LEFT") {
    line(10, 20, 50, 20);
    line(40, 10, 50, 20);
    line(40, 30, 50, 20);    
  }
  if (dir=="RIGHT") {
    line(10, 20, 50, 20);
    line(20, 10, 10, 20);
    line(20, 30, 10, 20);   
  }
  if (dir=="FORWARDS") {
    translate(0, -10);
    line(20, 20, 30, 10);
    line(30, 10, 40, 20);
    line(30, 10, 30, 50);
  }
  if (dir=="BACKWARDS") {
    translate(0, -10);
    line(30, 10, 30, 50);
    line(20, 40, 30, 50);
    line(40, 40, 30, 50);
  }
  pop();
}

class Zone
{
  float i; //angle (radians)
  color c; //color of circle
  float x, y, track_x, track_y; // x, y are stage locations, 
                              //track_x, track_y are locations relative to the center of the circle (the square)
  float radius, r_max;  //radius is the radius between circle and the center square
  int fadeNum, timer;

  Zone(float X, float Y, int R_MAX) {
    x = X;
    y = Y;
    i = atan2(y, x);  //start w/ radius of 90 degrees
    radius = dist(width/2, height/2, x, y); //define radius
    track_x = radius * cos(i);  //grab x position from center
    track_y = radius * sin(i);  //y position from center
    r_max = R_MAX;
    c = color(0, 0, 0);
    fadeNum=255;
    timer=0;
  }

  void update()
  {
    //trig stuff
    noStroke();
    fill(c);

    radius = dist(width/2, height/2, x, y);  // calculate radius

    //not yeilding a negative track_y
    if (moveY) {  //if we are moving forwards or backwards along the y axis
  
      //use cosA=b/c
      //working if rotating clockwise
      //float temp2 = track_y/track_x;
      //grab updated angle 
      //translate(width/2, height/2); 
      i = atan2(y-(height/2), x-(width/2));
      //update ellipse data in relation to center point
      track_x = radius * cos(i);
      track_y = -(radius * sin(i));
      //draw out ellipse
      ellipse(x, y, 5, 5);

    } else { 
        //reposition the ellipse according to the current radius and angle
        track_x = radius * cos(i);
        track_y = radius * sin(i);
        //update stage position
        x = width/2+track_x;
        y = height/2+track_y;
        ellipse(x, y, 5, 5);
    } 

    ellipseMode(CENTER_RADIUS);
    //draw simple animation
    if (timer<r_max) {
      timer++;
      fill(0, 0, 0, 0);
      stroke(0, 0, 0, fadeNum);
      ellipse(x, y, 5+(timer), 5+(timer));
      fadeNum-=2;
    } else {
        timer = 0;
        //timerMax = int(random(40)+20);
        fadeNum=100;
    } 
    
    //check if player is within radius
    if (radius<r_max) {
      c = color(150, 150, 150);
    } else {
      c = color(0, 0, 0);
    }
  
  }









} // end of class Zone