//////////////////////////////Ball Tag//////////////////////////////
//You are in control of a little blue ball, which you use to catch//
//the red or green circles. Catching a red circle will make you   //
//grow, and catching a green circle will make you shrink. Keep    //
//going until you no longer can! Use the arrow keys to move.      //
////////////////////////////////////////////////////////////////////

//VARIABLES

//Circle variables
float circlePositionRedX, circlePositionRedY;
float circlePositionGreenX, circlePositionGreenY;
float circleRadius = 20; 
float circleSpeed = 4.5;


//Ball Variables
float ballPositionX, ballPositionY;
float ballRadius = 10; 
float ballSpeed =2;

float c1x, c1y;
float c2x, c2y;
float r1, r2;

////////////////////////////////////////////////////////////////////////////
//SETUP

void setup() {
  size (400, 400);
  updateBall();
  updateRedCircle();
  updateGreenCircle();
}

////////////////////////////////////////////////////////////////////////////
//UPDATE

//where the ball is at the start - center of the screen
void updateBall() {
  ballPositionX = random (200, 200);
  ballPositionY = random (200, 200);
}

//where the red circle is at the start - offscreen
void updateRedCircle() {
  circlePositionRedX = random (0, height+1);
  circlePositionRedY = random (0, height-1);
}

//where the green circle is at the start - offscreen
void updateGreenCircle() {
  circlePositionGreenX = random (0, height+1);
  circlePositionGreenY = random (0, height-1);
}

//if the red circle overlaps with the blue ball, the blue ball grows larger
void redOverlap() {
  if (ballGrow(ballPositionX, ballPositionY, ballRadius, circlePositionRedX, circlePositionRedY, circleRadius)) {
    ballRadius+=0.07;
   
  }
}

//if the green circle overlaps with the blue ball, the blue ball grows smaller
void greenOverlap() {
  if (ballShrink(ballPositionX, ballPositionY, ballRadius, circlePositionGreenX, circlePositionGreenY, circleRadius)) {
    ballRadius-=0.07;
   
  }
}


////////////////////////////////////////////////////////////////////////////
//DRAW

void draw() {

  background (230);

  displayBallMovement();
  displayBall(); 

  displayRedCircle();
  displayGreenCircle();


  displayRedCircleMovement();
  displayGreenCircleMovement();

  displayBallOnScreen();
  displayRedCircleOnScreen();
  displayGreenCircleOnScreen();

  redOverlap();
  greenOverlap();
}
////////////////////////////////////////////////////////////////////////////
//FUNCTIONS

void displayBallMovement() {
  // moves the ball when an arrow key is pressed; ex, goes left when left key is pressed
  if (keyPressed) {
    if (keyCode == UP) {
      ballPositionY-=ballSpeed;
    } else if (keyCode == DOWN) {
      ballPositionY+=ballSpeed;
    } else if (keyCode == RIGHT) {
      ballPositionX+=ballSpeed;
    } else if (keyCode == LEFT) {
      ballPositionX-=ballSpeed;
    }
  }
}

void displayBall() {
  //appearance of ball
  noStroke();
  //body
  fill(0, 150, 200);
  ellipse(ballPositionX, ballPositionY, ballRadius, ballRadius);
}

void displayRedCircle() {
  //appearance of red circle - going from left to right
  noStroke();
  fill(150, 0, 0);
  ellipse(circlePositionRedX, circlePositionRedY, circleRadius, circleRadius);
}

void displayGreenCircle() {
  //appearance of green circle - going from top to bottom
  noStroke();
  fill(0, 150, 0);
  ellipse(circlePositionGreenX, circlePositionGreenY, circleRadius, circleRadius);
}

void displayRedCircleMovement() {
  //controls the movement of red circle
  //go from left to right
  circlePositionRedX+=circleSpeed;
  //make it reappear after going offscreen
  if (circlePositionRedX >+450) {
    circlePositionRedX = width - 350;
    circlePositionRedY = random (0, 420);
  }
}

void displayGreenCircleMovement() {
  //controls the movement of green circle
  //go from top to bottom
  circlePositionGreenY+=circleSpeed;
  //make it reappear after going offscreen
  if (circlePositionGreenY >+450) {
    circlePositionGreenY = height - 350;
    circlePositionGreenX = random (0, 420);
  }
}

void displayBallOnScreen() {
  //to keep the Ball from moving offscreen - stops it at the edge
  if (ballPositionY < 10) {
    ballPositionY = 10;
  } else {
    if (ballPositionY > 390) {
      ballPositionY = 390;
    } else {
      if (ballPositionX < 10) {
        ballPositionX = 10;
      } else {
        if (ballPositionX > 390) {
          ballPositionX = 390;
        }
      }
    }
  }
}

void displayRedCircleOnScreen() {
  //to keep the red circle from appearing half offscreen
  if (circlePositionRedY < 150) {
    circlePositionRedY = 150;
  } else { 
    if (circlePositionRedY > 270) {
      circlePositionRedY = 270;
    } else {
      if (circlePositionRedX < 60) {
        circlePositionRedX = 60;
      }
    }
  }
}


void displayGreenCircleOnScreen() {
  //to keep the green circle from appearing half offscreen
  if (circlePositionGreenY < 50) {
    circlePositionGreenY = 50;
  } else { 
    if (circlePositionGreenX > 270) {
      circlePositionGreenX = 270;
    } else {
      if (circlePositionGreenX < 20) {
        circlePositionGreenX = 20;
      }
    }
  }
}

////////////////////////////////////////////////////////////////////////////
//INTERSECTIONS

//make the ball grow when it intersects with red
boolean ballGrow(float c1x, float c1y, float r1, float c2x, float c2y, float r2) {
  if (dist(c1x, c1y, c2x, c2y) < r1 + r2) {
    return true;
  } else {
    return false;
  }
}

//make the ball shrink when it intersects with green
boolean ballShrink(float c1x, float c1y, float r1, float c2x, float c2y, float r2) {
  if (dist(c1x, c1y, c2x, c2y) < r1 + r2) {
    return true;
  } else {
    return false;
  }
}

////////////////////////////////////////////////////////////////////////////