#include <SDL/SDL.h>
#include <math.h>
#include <time.h>


#define FPS		40
#define X_S		600
#define Y_S		600
#define PPC		20
#define SIZE_P		2

typedef struct
{
	int x;
	int y;

}Balle;

SDL_Surface* screen = NULL;
void putPixel(SDL_Surface * surface, Uint16 x, Uint16 y, Uint32 color)
{
    Uint8 bpp = surface->format->BytesPerPixel;
    Uint8 * p = ((Uint8 *)surface->pixels) + y * surface->pitch + x * bpp;
     switch(bpp)
    {
	  case 1:
		*p = (Uint8) color;
		break;
        case 2:
            *(Uint16 *)p = (Uint16) color;
            break;
        case 3:
            if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
            {
                *(Uint16 *)p = ((color >> 8) & 0xff00) | ((color >> 8) & 0xff);
                *(p + 2) = color & 0xff;
            }
            else
            {
                *(Uint16 *)p = color & 0xffff;
                *(p + 2) = ((color >> 16) & 0xff) ;
            }
            break;
        case 4:
            *(Uint32 *)p = color;
            break;
    }
}
void ERNO(int error, char* t)
{
	switch(error)
	{
		case 1:
			printf("Init error");break;
		case 2:
			printf("Alloc error");
	}
	if(t)
		putchar(':'),puts(t);
	exit(error);
}


void pixel(int x,int y, int estVivant)
{
	int i,j;
	for(i=0;i<PPC;i++)
		for(j=0;j<PPC;j++)
			putPixel(screen, x*PPC+i,y*PPC+j, !estVivant * 0xFF);
}
void showAll(int pong,Balle balle)
{
	SDL_FillRect(screen, NULL, SDL_MapRGB(screen->format, 255, 255, 255));
	int i;
	for(i=0;i<=SIZE_P;i++)
		pixel(2, pong+i, 1);

	pixel(balle.x,balle.y,1);
	SDL_Flip(screen);
}
int main (void)
{
	int i,err=0;
	if ( SDL_Init(SDL_INIT_VIDEO) < 0 )
		ERNO(1,"SDL_Init");
	atexit(SDL_Quit);
  
	if(! (screen=SDL_SetVideoMode(X_S, Y_S, 8, SDL_SWSURFACE | SDL_DOUBLEBUF)))
 		ERNO(1,"VideoMode");
 	SDL_FillRect(screen, NULL, SDL_MapRGB(screen->format, 255, 255, 255));
 	SDL_Flip(screen);
	SDL_Event event;
 	while(SDL_WaitEvent(&event))if(event.type == SDL_QUIT)return 0;else if(event.type == SDL_KEYDOWN)break;

	i=0;
	SDL_EnableKeyRepeat(1, 0);
	int pong = 10, Xb=1, Yb=1, DV=1;
	Balle balle = {3, pong+1};

	while(1)
	{
		showAll(pong,balle);
		while(SDL_PollEvent(&event))
			if(event.type == SDL_QUIT)return 0;
			else if(event.type == SDL_KEYDOWN)
				switch (event.key.keysym.sym)
				{
					case SDLK_UP:
					if(pong)
						pong--;
					break;
					case SDLK_DOWN:
					if(pong<(X_S/PPC-3))
						pong++;
					break;
					case SDLK_p:
						exit(1);
					break;
					default:
						puts("Nothing");
				}
		if(balle.x == 2)
			if(balle.y >= pong && balle.y <= pong+SIZE_P)
					Yb= pong+1 - balle.y,Yb*=-1,Xb*=-1;
		if(DV)
		{
			if(!balle.x || balle.x == (X_S/PPC-1))
				Xb*=-1;
			if(!balle.x)
				printf("%d missing\n",++err);
			
			balle.x+=Xb;
			if(!(balle.y<(Y_S/PPC) && balle.y))
				Yb*=-1;
			balle.y+=Yb;
		}
		else
		{
			balle.x-=Yb;
			balle.y-=Xb;
		}
		
		SDL_Delay(25);
	}
	return 0;
}