#include <CtrlLib/CtrlLib.h>

#define SCREENWIDTH  600
#define SCREENHEIGHT 480

#define PADDLEWIDTH  12
#define PADDLEHEIGHT 40

#define BALLSIZE  8
#define BALLSPEED 5

enum Which { PLAYER, COMPUTER };

class Ball {
private:
	int bx;
	float by;												// Ball pos
	int sx;
	float sy;												// Ball speed
	int size;												// Ball size
	Point* samples;											// Vector samples for collision detection
	int numSamples;											// Number of samples to be taken
	int serve;												// Who the ball is being served to
public:
	Ball()			{ serve = -1; Reset(); }
	Rect GetRect()	{ Rect r(int(bx), int(by), int(bx + size), int(by + size)); return r; }
	void Update();
	void GetVectorSamples();
	void Reset();
};

void Ball::Reset() {
	size = BALLSIZE;										// Init ball size
	bx = (SCREENWIDTH - size) / 2;							// center ball horizontally
	by = (SCREENHEIGHT - size) / 2;							// center ball vertically
	sx = BALLSPEED * serve;									// Init ball x-speed
	sy = 0;	//TODO: Pick random angle						// Init ball y-speed (angle)
}

void Ball::GetVectorSamples() {
	numSamples = (sx > size) ? sx / size : 1;				// Number of samples to take
	float dy = sy / numSamples;								// Slope of ball movement
	samples = new Point[numSamples];
	for(int s = 1; s <= numSamples; s++) {
		samples[s - 1].x = bx + (s * size);					// Calculate sample x-pos
		samples[s - 1].y = int(by + (s * dy));				// Calculate sample y-pos
	}
}

void Ball::Update() {
	if(bx + sx > SCREENWIDTH) {								// Ball exits to right of screen
		// TODO: add score and re-serve ball
		serve = -1;
		Reset();
	} else if(bx + size + sx < 0) {							// Ball exits to left of screen
		// TODO: add score and re-serve ball
		serve = 1;
		Reset();
	} else {												// Ball is still in play
		GetVectorSamples();
		// [[ HOW DO I GET ACCESS TO PADDLE? player/computer are in Pong class ]]
		// TODO: Test each sample against nearest paddle for collision
		// TODO: Correct angle and direction of ball if collided
		// TODO: Else continue in direction:
		bx += sx;
		by += sy;
	}
}

class Player {
private:
	int score, px, py, height;
	Which who;
public:
	Player()		{ }
	Player(Which w);
	int GetScore() 	{ return score; }
	Rect GetRect()	{ Rect r(px, py, px + PADDLEWIDTH, py + height); return r; }
	void Update();
};

Player::Player(Which w) {
	score = 0;												// Init score
	py = (SCREENHEIGHT - PADDLEHEIGHT) / 2;					// Init paddle y-pos
	height = PADDLEHEIGHT;									// Init paddle height
	px = (w == PLAYER)
		? 10												// Set player paddle x-pos
		: SCREENWIDTH - PADDLEWIDTH - 10;					// Set computer paddle x-pos
}

void Player::Update() {
	switch(who) {
		case PLAYER:
			// TODO: Get mouse y pos
			break;
		case COMPUTER:
			// TODO: Move computer paddle toward ball
			break;	
	}
}

class Pong : public TopWindow {
public:
	void Paint(Draw& w);
private:
	Player player, computer;
	Ball ball;
public:
	typedef Pong CLASSNAME;
	Pong();
	void Update();
};

void Pong::Update() {
	// player.Update();										// Update player paddle position
	// computer.Update();									// Update computer paddle position
	ball.Update();											// Update ball position
	Refresh();	
}

void Pong::Paint(Draw& w) {
	w.DrawRect(GetSize(), SBlack);
	w.DrawRect(player.GetRect(), SWhite);
	w.DrawRect(computer.GetRect(), SWhite);
	w.DrawRect(ball.GetRect(), SWhite);
	/* For showing projected samples ( samples and numSamples need to be made public to work )
	for(int i = 0; i < ball.numSamples; i++) {
		//w.DrawText(SCREENWIDTH / 2, 10 + 10 * i, ball.samples[i].ToString(), StdFont(), SWhite);
		w.DrawRect(ball.samples[i].x, ball.samples[i].y, BALLSIZE, BALLSIZE, SWhite);
	}
	*/
}

Pong::Pong() {
	Title("Snap.Pong");
	SetRect(0, 0, SCREENWIDTH, SCREENHEIGHT);
	MinimizeBox();
	
	player = Player(PLAYER);								// Init player
	computer = Player(COMPUTER);							// Init computer
	
	BackPaint();
	Update();
	SetTimeCallback(-25, THISBACK(Update));
}

GUI_APP_MAIN
{
	Pong().Run();
}