class Snake
{
  SnakePoint snakeGrid [][] = new SnakePoint[41][41];
  SnakePoint head;
  SnakePoint tail;
  String snakeDirection;

  //powerups
  int speed;
  int growAmount;
  int growCounter;


  Snake otherSnake;
  int initialY;
  String controls;



  class SnakePoint
  {
    int x;
    int y;
    String nextPointDirection;
    boolean isSnake;
    SnakePoint(boolean _isSnake, String _nextPointDirection, int _x, int _y)
    {
      x = _x;
      y = _y;
      isSnake = _isSnake;
      nextPointDirection = _nextPointDirection;
    }
  }

  Snake(int _initialY, String _controls)
  {
    growCounter = 0;
    controls = _controls;
    initialY = _initialY;
    otherSnake = null;
    speed = 6;
    growAmount = 3;
    for(int i = 0; i < 41; i++)
    {
      for(int j = 0; j < 41; j++)
      {
        snakeGrid[i][j] = new SnakePoint(false, "", i, j);
      }
    }
    initSnake();
  }

  void setOtherSnake(Snake s)
  {
    otherSnake = s;
  }

  void initSnake()
  {
    snakeGrid[10][initialY].isSnake = true;
    snakeGrid[10][initialY].nextPointDirection = "right";

    snakeGrid[11][initialY].isSnake = true;
    snakeGrid[11][initialY].nextPointDirection = "right";

    snakeGrid[12][initialY].isSnake = true;
    snakeGrid[12][initialY].nextPointDirection = "right";

    head = snakeGrid[12][initialY];
    tail = snakeGrid[10][initialY];

    snakeDirection = "right";
  }

  boolean isSnakeSquare(int x, int y)
  {
    return snakeGrid[x][y].isSnake;
  }

  boolean moveSnake(int _x, int _y)
  {
    boolean _moveTail = true;
    snakeGrid[head.x][head.y].nextPointDirection = snakeDirection;
    if (p.ghost() == true)
    {
      //move the snake only if
      if(

          isSnakeSquare(head.x + _x, head.y + _y) ||
          (otherSnake != null && otherSnake.isSnakeSquare(head.x + _x, head.y + _y)) ||
          head.x + _x >=40 ||
          head.x + _x <=0 ||
          head.y + _y >=40 ||
          head.y + _y <=0
        )
      {
        //Collision
        return true;
      }
    }
    else
    {
      //move the snake only if
      if(

          isSnakeSquare(head.x + _x, head.y + _y) ||
          (otherSnake != null && otherSnake.isSnakeSquare(head.x + _x, head.y + _y)) ||
          head.x + _x >=40 ||
          head.x + _x <=0 ||
          head.y + _y >=40 ||
          head.y + _y <=0
        )
      {
        //Collision
        return true;
      }
    }

    if (apple.getApple(head.x + _x,  head.y + _y)) growCounter = growAmount;


    if (p.getPowerup(head.x + _x, head.y + _y))
    {
      p.movePowerup();
    }
    this.speed = p.haste();
    this.growAmount = p.doubleLength();


    snakeGrid[head.x + _x][head.y + _y].isSnake = true;
    head = snakeGrid[head.x + _x][head.y + _y];
    if (growCounter > 0)
    {
      growCounter --;
    }
    else
    {
      moveTail();
    }

    //No Collision
    return false;
  }

  void moveTail()
  {
    tail.isSnake = false;

    if(tail.nextPointDirection == "up") tail = snakeGrid[tail.x][tail.y - 1];
    else if(tail.nextPointDirection == "down") tail = snakeGrid[tail.x][tail.y + 1];
    else if(tail.nextPointDirection == "right") tail = snakeGrid[tail.x + 1][tail.y];
    else if(tail.nextPointDirection == "left") tail = snakeGrid[tail.x - 1][tail.y];
  }
  int countDown;
  boolean drawSnake()
  {
    countDown--;
    if(countDown <= 0)
    {
      keyPressed();
      if(snakeDirection == "up")
      {
        if (moveSnake(0, -1)) return true;
      }
      else if(snakeDirection == "down")
      {
        if (moveSnake(0, 1)) return true;
      }
      else if(snakeDirection == "right")
      {
        if (moveSnake(1, 0)) return true;
      }
      else if(snakeDirection == "left")
      {
        if (moveSnake(-1, 0)) return true;
      }
      countDown = speed;
    }
    return false;
  }

  void keyPressed()
  {
    if(p.dizzy() == false)
    {
        //UP
        if      (
                 (keyCode == UP)            && controls == "arrows"  ||
                 (key == 'w' || key == 'W') && controls == "wasd"
                )
        {
          if (snakeDirection == "up" || snakeDirection == "down") return;
          snakeDirection = "up";
        }

        //DOWN
        else if (
                  (keyCode == DOWN)          && controls == "arrows"  ||
                  (key == 's' || key == 'S') && controls == "wasd"
                )
        {
          if (snakeDirection == "up" || snakeDirection == "down") return;
          snakeDirection = "down";
        }

        //RIGHT
        else if (
                  (keyCode == RIGHT)         && controls == "arrows"  ||
                  (key == 'd' || key == 'D') && controls == "wasd"
                )
        {
          if (snakeDirection == "right" || snakeDirection == "left") return;
          snakeDirection = "right";
        }

        //LEFT
        else if (
                  (keyCode == LEFT)          && controls == "arrows"  ||
                  (key == 'a' || key == 'A') && controls == "wasd"
                )
        {
          if (snakeDirection == "right" || snakeDirection == "left") return;
          snakeDirection = "left";
        }
    }
    //INVERT CONTROLS
    else
    {
        //UP
        if      (
                 (keyCode == UP)            && controls == "arrows"  ||
                 (key == 'w' || key == 'W') && controls == "wasd"
                )
        {
          if (snakeDirection == "up" || snakeDirection == "down") return;
          snakeDirection = "down";
        }

        //DOWN
        else if (
                  (keyCode == DOWN)          && controls == "arrows"  ||
                  (key == 's' || key == 'S') && controls == "wasd"
                )
        {
          if (snakeDirection == "up" || snakeDirection == "down") return;
          snakeDirection = "up";
        }

        //RIGHT
        else if (
                  (keyCode == RIGHT)         && controls == "arrows"  ||
                  (key == 'd' || key == 'D') && controls == "wasd"
                )
        {
          if (snakeDirection == "right" || snakeDirection == "left") return;
          snakeDirection = "left";
        }

        //LEFT
        else if (
                  (keyCode == LEFT)          && controls == "arrows"  ||
                  (key == 'a' || key == 'A') && controls == "wasd"
                )
        {
          if (snakeDirection == "right" || snakeDirection == "left") return;
          snakeDirection = "right";
        }
    }
  }
}

class Apple
{
  int x;
  int y;
  Apple()
  {
    moveApple();
  }

  void moveApple()
  {
    x = (int)random(1,40);
    y = (int)random(1,40);
  }

  boolean getApple(int _x, int _y)
  {
    if ( x == _x && y == _y)
    {
      moveApple();
      return true;
    }
    return false;
  }

  boolean isApple(int _x, int _y)
  {
    if ( x == _x && y == _y)
    {
      return true;
    }
    return false;
  }
}

class Renderer
{
  void drawBoardSingle()
  {
    for(int i = 0; i < 41; i++)
    {
      for(int j = 0; j < 41; j++)
      {
          color colour;
          if (apple.isApple(i,j)) colour = #8B4513;
          else if (s1.isSnakeSquare(i,j)) colour = #00ff00;
          else if (p.isPowerup(i,j)) colour = p.getColour();
          else colour = #5ba4d8;
          p.countDown--;
          fill(colour);
          stroke(255,255,255,80);
          rect(i*20, j*20, 20, 20);
        }
      }
    }
  void drawBoardMulti()
  {
    println("drawboardmulti");
    for(int i = 0; i < 41; i++)
    {
      for(int j = 0; j < 41; j++)
      {
          color colour;
          if (apple.isApple(i,j)) colour = #8B4513;
          else if (s1.isSnakeSquare(i,j)) colour = #00ff00;
          else if (s2.isSnakeSquare(i,j)) colour = #ff0000;
          else if (p.isPowerup(i,j)) colour = p.getColour();
          else colour = #5ba4d8;
          p.countDown--;
          fill(colour);
          stroke(255,255,255,80);
          rect(i*20, j*20, 20, 20);
        }
      }
    }
  void drawCollision()
  {
    for(int i = 0; i < 41; i++)
      {
        color colour = #ff0000;
        fill(colour);
        stroke(255,255,255,80);
        rect(i*20, 0*20, 20, 20);
        rect(0*20, i*20, 20, 20);
        rect(i*20, 40*20, 20, 20);
        rect(40*20, i*20, 20, 20);
      }
  }
}

class Powerup
{
  int x;
  int y;
  int m = -1;
  long countDown = 0;
  color powerupColour;
  boolean isAvailable = true;
  String type = "none";
  int choose;
  int haste()
  {
    m--;
    println(m + " " + countDown + " " + s1.speed);
    if (choose == 1)
    {
      if (m<0)
      return 6;
      else
      return 4;
    }
    else if (choose == 4)
    {
      if (m<0)
      return 6;
      else
      return 12;
    }
    return 6;
  }
  int doubleLength()
  {
    println(m + " " + countDown);
    if (choose == 2)
    {
      if (m<0)
        return 3;
      else
        return 6;
    }
    return 3;
  }
  boolean dizzy()
  {
    if (choose == 4)
    {
      if (m<0)
      return true;
      else
      return false;
    }
    else return false;
  }
  boolean ghost()
  {
    if (choose == 3)
    {
      if (m<0)
      return true;
      else
      return false;
    }
    else return false;
  }
  void choosePowerup()
  {
    choose = 3;//(int)random(1,5);
    if (choose == 1) type = "haste";
    if (choose == 2) type = "doubleLength";
    if (choose == 3) type = "ghost";
    if (choose == 4) type = "dizzy";
  }
  Powerup()
  {
    movePowerup();
  }
  color getColour()
  {
    if (isAvailable) return #00AA00;
    else return #5ba4d8;
  }
  void movePowerup()
  {
      choosePowerup();
      x = (int)random(1,40);
      y = (int)random(1,40);
  }

  boolean getPowerup(int _x, int _y)
  {
    countDown--;
    if (countDown <= 0)
    {
      isAvailable = true;
      if ( x == _x && y == _y)
      {
        movePowerup();
        countDown = 500000;
        isAvailable = false;
        m = 120;
        return true;
      }
    }
    return false;
  }

  boolean isPowerup(int _x, int _y)
  {
    if ( x == _x && y == _y)
    {
      return true;
    }
    return false;
  }
}

//make a new snake
String gameMode = "single";
Apple apple = new Apple();
Renderer renderer = new Renderer();
boolean gameOver;
boolean restart;
Snake s1;
Snake s2;
Powerup p = new Powerup();

int mode;
void chooseGameMode(int select)
{
  if (select == 1)
  {
    mode = 1;
    s1 = new Snake(10, "arrows");
    println("Single");
  }
  if (select == 2)
  {
   mode = 2;
   s1 = new Snake(10, "arrows");
   s2 = new Snake(20, "wasd");
   s1.setOtherSnake(s2);
   s2.setOtherSnake(s1);
   println("Multi");
  }
}



void setup()
{
  gameOver = false;
  chooseGameMode(1);
  size(1000,1000);
  frameRate(60);
  background(255,255,255);
}



void keyReleased()
{
  //RESTART
  if (key == 'p' || key == 'P')
  {
    if(restart == false)
    {
      restart = true;
    }
  }
}

void draw()
{
  if (!gameOver)
  {
    if (gameMode == "single")
    {
      if(s1.drawSnake())
      {
        renderer.drawCollision();
        println("game over");
        gameOver = true;
      }
      else
      {
        if (gameMode == "multi") renderer.drawBoardMulti();
        if (gameMode == "single") renderer.drawBoardSingle();
      }
   }
   else if (gameMode == "multi")
   {
     if(s1.drawSnake() || s2.drawSnake())
     {
       renderer.drawCollision();
       println("game over");
       gameOver = true;
     }
     else
     {
       if (gameMode == "multi") renderer.drawBoardMulti();
       if (gameMode == "single") renderer.drawBoardSingle();
     }
   }
  }

  //restart the game
  if (gameOver)
  {
    if (restart)
    {
      gameOver = false;
      s1 = new Snake (10, "arrows");
      if (gameMode == "multi")
      {
        s2 = new Snake(20, "wasd");
        s1.setOtherSnake(s2);
        s2.setOtherSnake(s1);
      }
      println("restart");
      restart = false;
    }
  }

}