#include <stdlib.h>

#include <math.h>

#include <SDL_events.h>

#include <SDL_rect.h>

#include <SDL_pixels.h>

#include <SDL_video.h>

#include <SDL_shape.h>

#define SHAPED_WINDOW_X 150

#define SHAPED_WINDOW_Y 150

#define SHAPED_WINDOW_DIMENSION 640

int main(int argc,char** argv) {

        if(argc < 2) {

        	printf("SDL_Shape requires at least one bitmap file as argument.\n");

        	exit(-1);

        }

	if(SDL_VideoInit(NULL,0) == -1) {

		printf("Could not initialize SDL video.\n");

		exit(-2);

	}

	Uint8 num_pictures = argc - 1;

	SDL_Surface **pictures = malloc(sizeof(SDL_Surface*)*num_pictures);

	int i = 0;

	for(i=0;i<num_pictures;i++)

		pictures[i] = NULL;

	for(i=0;i<num_pictures;i++) {

		pictures[i] = SDL_LoadBMP(argv[i+1]);

		if(pictures[i] == NULL) {

			int j = 0;

			for(j=0;j<num_pictures;j++)

				if(pictures[j] != NULL)

					SDL_FreeSurface(pictures[j]);

			free(pictures);

			SDL_VideoQuit();

			printf("Could not load surface from named bitmap file.\n");

			exit(-3);

		}

	}

	SDL_Window *window = SDL_CreateShapedWindow("SDL_Shape test",SHAPED_WINDOW_X,SHAPED_WINDOW_Y,SHAPED_WINDOW_DIMENSION,SHAPED_WINDOW_DIMENSION,SDL_WINDOW_RESIZABLE | SDL_WINDOW_SHOWN);

	if(window == NULL) {

		for(i=0;i<num_pictures;i++)

			SDL_FreeSurface(pictures[i]);

		free(pictures);

		SDL_VideoQuit();

		printf("Could not create shaped window for SDL_Shape.\n");

		exit(-4);

	}

	if(SDL_CreateRenderer(window,-1,SDL_RENDERER_PRESENTFLIP2) == -1) {

		SDL_DestroyWindow(window);

		for(i=0;i<num_pictures;i++)

			SDL_FreeSurface(pictures[i]);

		free(pictures);

		SDL_VideoQuit();

		printf("Could not create rendering context for SDL_Shape window.\n");

		exit(-5);

	}

	SDL_Texture **textures = malloc(sizeof(SDL_Texture*)*num_pictures);

	for(i=0;i<num_pictures;i++)

		textures[i] = NULL;

	for(i=0;i<num_pictures;i++) {

		textures[i] = SDL_CreateTextureFromSurface(0,pictures[i]);

		if(textures[i] == NULL) {

			int j = 0;

			for(j=0;j<num_pictures;i++)

				if(textures[i] != NULL)

					SDL_DestroyTexture(textures[i]);

			free(textures);

			for(i=0;i<num_pictures;i++)

				SDL_FreeSurface(pictures[i]);

			free(pictures);

			SDL_DestroyRenderer(window);

			SDL_DestroyWindow(window);

			SDL_VideoQuit();

			printf("Could not create texture for SDL_shape.\n");

			exit(-6);

		}

	}

	SDL_Event event;

	int event_pending = 0,should_exit = 0;

	event_pending = SDL_PollEvent(&event);

	unsigned int current_picture = 0;

	SDL_WindowShapeMode mode = {ShapeModeDefault,1};

	Uint32 format = 0,access = 0;

	SDL_Rect texture_dimensions = {0,0,0,0};

	SDL_QueryTexture(textures[current_picture],&format,&access,&texture_dimensions.w,&texture_dimensions.h);

	SDL_SetWindowSize(window,texture_dimensions.w,texture_dimensions.h);

	SDL_SetWindowShape(window,pictures[current_picture],&mode);

	while(should_exit == 0) {

		event_pending = SDL_PollEvent(&event);

		if(event_pending == 1) {

				current_picture += 1;

				if(current_picture >= num_pictures)

					current_picture = 0;

				SDL_QueryTexture(textures[current_picture],&format,&access,&texture_dimensions.w,&texture_dimensions.h);

				SDL_SetWindowSize(window,texture_dimensions.w,texture_dimensions.h);

				SDL_SetWindowShape(window,pictures[current_picture],&mode);

			}

			if(event.type == SDL_QUIT)

				should_exit = 1;

			event_pending = 0;

		}

		SDL_SelectRenderer(window);

		//Clear render-target to blue.

		SDL_SetRenderDrawColor(0x00,0x00,0xff,0xff);

		SDL_RenderClear();

		//Render the texture.

		SDL_RenderCopy(textures[current_picture],&texture_dimensions,&texture_dimensions);

		SDL_RenderPresent();

	}

	//Free the textures.

	for(i=0;i<num_pictures;i++)

		SDL_DestroyTexture(textures[i]);

	free(textures);

	//Destroy the window.

	SDL_DestroyWindow(window);

	//Free the original surfaces backing the textures.

	for(i=0;i<num_pictures;i++)

		SDL_FreeSurface(pictures[i]);

	free(pictures);

	//Call SDL_VideoQuit() before quitting.

	SDL_VideoQuit();

}