#include <SDL.h>

Uint32 fp10s_acc = 0;

Uint32 fp10s_acc_samples = 0;

int w = 512;

int h = 384;

void update(Raytracer &rt, SDL_Surface *screen, Float *render_buffer)

{

	static Uint32 t = 0;

	Uint32 tnow = SDL_GetTicks();

	int fp10s = 10000/(int)(tnow - t);

	if (t != 0)

	{

		fp10s_acc += fp10s;

		++fp10s_acc_samples;

	}

	t = tnow;

	char s[40];

	sprintf(s, "fps:%3d.%1d", fp10s/10, fp10s%10);

	SDL_WM_SetCaption(s, NULL);

	rt.render(w, h, render_buffer);

	if (SDL_MUSTLOCK(screen))

		if (SDL_LockSurface(screen) < 0)

			return;

	Uint32 *bufp = (Uint32 *)screen->pixels;

	unsigned char c[3];

	for (Float *fd = render_buffer; fd != render_buffer + w*h*3; fd += 3)

	{

		for (int i = 0; i < 3; i++)

		{

			if (fd[i] > 1.0)

				c[i] = 255;

			else

				c[i] = (unsigned char)(fd[i] * 255.0);

		}

		*bufp = SDL_MapRGB(screen->format, c[0], c[1], c[2]);

		bufp++;

	}

	if (SDL_MUSTLOCK(screen))

		SDL_UnlockSurface(screen);

	if (screen->flags & SDL_DOUBLEBUF)

		SDL_Flip(screen);

	else

		SDL_UpdateRect(screen, 0, 0, w, h);

}

void loop_sdl(Raytracer &rt, Camera &cam,

	void (*update_callback)() = NULL, void (*key_callback)(int, int) = NULL)

{

	SDL_Surface *screen;

	Float *render_buffer;

	pyrit_verbosity = 0;

	render_buffer = (Float *) malloc(w*h*3*sizeof(Float));

	if( SDL_Init(SDL_INIT_VIDEO) < 0 ) {

		fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());

		exit(1);

	}

	screen = SDL_SetVideoMode(w, h, 32, SDL_SWSURFACE|SDL_DOUBLEBUF|SDL_RESIZABLE);

	if ( screen == NULL ) {

		fprintf(stderr, "Unable to set video mode: %s\n", SDL_GetError());

		exit(1);

	}

	SDL_Event event;

	bool quit = false;

	Float roty = 0.0, rotx = 0.0, move = 0.0;

	while (!quit)

	{

		while (SDL_PollEvent(&event))

		{

			switch (event.type) {

				case SDL_VIDEORESIZE:

					w = (event.resize.w-1) / 8 * 8 + 8;

					h = (event.resize.h-1) / 8 * 8 + 8;

					render_buffer = (Float *) realloc(render_buffer, w*h*3*sizeof(Float));

					screen = SDL_SetVideoMode(w, h, 32, SDL_HWSURFACE|SDL_DOUBLEBUF|SDL_RESIZABLE);

					break;

				case SDL_KEYDOWN:

					if (event.key.keysym.sym == SDLK_ESCAPE) {

						quit = true;

						break;

					}

					if (event.key.keysym.sym == SDLK_LEFT) {

						roty = -0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_RIGHT) {

						roty = +0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_DOWN) {

						rotx = +0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_UP) {

						rotx = -0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_w) {

						move = +0.5;

						break;

					}

					if (event.key.keysym.sym == SDLK_s) {

						move = -0.5;

						break;

					}

					if (event.key.keysym.sym == SDLK_c) {

						// print camera coordinates

						cout << "Camera: eye=" << cam.eye

						<< ", p=" << cam.p

						<< ", u=" << cam.u

						<< ", v=" << cam.v

						<< endl;

						break;

					}

					if (key_callback != NULL)

						key_callback(event.key.keysym.sym, 1);

					break;

				case SDL_KEYUP:

					if (event.key.keysym.sym == SDLK_LEFT || event.key.keysym.sym == SDLK_RIGHT) {

						roty = 0.0;

						break;

					}

					if (event.key.keysym.sym == SDLK_UP || event.key.keysym.sym == SDLK_DOWN) {

						rotx = 0.0;

						break;

					}

					if (event.key.keysym.sym == SDLK_w || event.key.keysym.sym == SDLK_s) {

						move = 0.0;

						break;

					}

					if (key_callback != NULL)

						key_callback(event.key.keysym.sym, 0);

					break;

				case SDL_QUIT:

					quit = true;

			}

		}

		cam.rotate(Quaternion(cos(roty),0,sin(roty),0).normalize());

		cam.rotate(Quaternion(cos(rotx),cam.u[0]*sin(rotx),0,cam.u[2]*sin(rotx)).normalize());

		cam.u.y = 0;

		cam.u.normalize();

		if (move != 0.0)

			cam.move(move,0,0);

		if (update_callback != NULL)

			update_callback();

		update(rt, screen, render_buffer);

	}

	free(render_buffer);

	Uint32 fp100s_aver = fp10s_acc*10/fp10s_acc_samples;

	printf("averlage fps: %3d.%2d\n\n", fp100s_aver/100, fp100s_aver%100);

	SDL_Quit();

}