#ifndef CLASS_TIMER
#define CLASS_TIMER

#include <SDL.h>

#define MAX_FPS 100
#define MIN_FPS 30
#define DEFAULT_FPS 50
#define MS_X_SEC 1000

/// This class is used to control FPS of the game
class Timer
{
	private:
	 /// time elapsed in the game
	 Uint32 _game_time;
	 /// loop start time 
	 Uint32 _t1;
	 /// loop end time
	 Uint32 _t2;
	 /// time elapsed during a loop
	 Uint32 _t_diff;
	 /// how much a frame should be
	 int _frame_time;
	 /// wanted frame rate
	 int  _frame_rate;
	 /// frames blitted
	 int _num_frames;
	 /// time elapsed, used to check if a second has passed
	 Uint32 _t_sec;
	 /// current FPS
	 int _fps;

	public:
	 /// constructor, set the wanted Frame Rate
	 Timer(int fr) 
	 {
		_frame_rate = fr;
		_frame_time = MS_X_SEC / fr; 
	 };

	 /// destroyer
	 ~Timer() { };

	 /// start the timer, it's an init required before the game loop
	 void Start() 
	 { 
		_game_time = _t1 = SDL_GetTicks(); 
		_t_diff = _num_frames =  _t_sec = _fps = 0;
	 };

	 /// set delay so to have a constant Frame Rate
	 void Delay();

	 /// compute time elapsed on each loop
	 void GoOn();

	 /// set wanted Frame Rate
	 void SetFrameRate(int fr)
	 {
		_frame_rate = fr;
		_frame_time = MS_X_SEC / fr; 
	 };
	 /// return wanted Frame Rate
	 int GetFrameRate() { return _frame_rate; }

	 /// return time elapsed during last loop
	 Uint32 GetElapsedTime() { return _t_diff; };

	 /// return current FPS
	 int GetFps() { return _fps; };
};

#endif