// Author : Jovian HERSEMEULE
#include <iostream>
#include <SDL/SDL.h>

int main()
{
	/// [1] Start
	// [1.1] Start SDL
	if ( SDL_Init( SDL_INIT_VIDEO ) < 0)
	{
		std::cout << "Can't initialize SDL: " << SDL_GetError() << std::endl;
		return 1;
	}

	// [1.2] Anticipate quit
	atexit(SDL_Quit);

	// [1.3] Set title
	SDL_WM_SetCaption("Application SDL", 0);

	/// [2] Create components
	// [2.1] Create window
	const int width(640), height(480);
	SDL_Surface* screen = SDL_SetVideoMode(width, height, 32, SDL_HWSURFACE|SDL_DOUBLEBUF);
	if ( !screen )
	{
		std::cout << "Unable to set " << width << "x" << height << " video: " << SDL_GetError() << std::endl;
		return 1;
	}

	// [2.2] Other components
	SDL_Surface* grass = SDL_LoadBMP("textures/grass.bmp");
	SDL_Surface* pawn = SDL_LoadBMP("textures/pawn.bmp");
	SDL_Rect pos({0, 0, 0, 0});
	SDL_Rect pawnPos({0, 0, 0, 0});

	/// [3] Main loop
	bool done(false);
	while (!done)
	{
		// [3.1] Events
		SDL_Event event;
		while (SDL_PollEvent(&event))
		{
			switch (event.type)
			{
				case SDL_QUIT:
					done = true;
					break;
				case SDL_KEYDOWN:
					if (event.key.keysym.sym == SDLK_ESCAPE)
						done = true;
					break;
				case SDL_MOUSEMOTION:
					pawnPos.x = event.motion.x - pawn->w / 2;
					pawnPos.y = event.motion.y - pawn->h / 2;
					break;
			} // end switch event type
		} // end of message processing

		// [3.2] Compute
		// Nothing for now

		// [3.3] Draw phase
		SDL_FillRect(screen, 0, SDL_MapRGB(screen->format, 0, 255, 255));

		for (pos.y = 0; pos.y < height; pos.y += grass->h)
			for (pos.x = 0; pos.x < width; pos.x += grass->w)
				SDL_BlitSurface(grass, NULL, screen, &pos);

		SDL_BlitSurface(pawn, NULL, screen, &pawnPos);

		SDL_Flip(screen);

		SDL_Delay(16);
	} // end of main loop

	///[4] Free components
	SDL_FreeSurface(grass);
	SDL_FreeSurface(pawn);

	SDL_FreeSurface(screen);

	std::cout << "No error caught." << std::endl;
	return 0;
}