#include <stdlib.h>

 #include <math.h>

 #include <stdio.h>

 #include "SDL.h"

 #include "SDL_shape.h"

 #define SHAPED_WINDOW_X 150

 #define SHAPED_WINDOW_Y 150

 #define SHAPED_WINDOW_DIMENSION 640

 #define TICK_INTERVAL 1000/10

 typedef struct LoadedPicture {

 	SDL_Surface *surface;

 	SDL_Texture *texture;

 	SDL_WindowShapeMode mode;

 } LoadedPicture;

 void render(SDL_Window* window,SDL_Texture *texture,SDL_Rect texture_dimensions) {

 	SDL_SelectRenderer(window);

 	//Clear render-target to blue.

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

 	SDL_RenderClear();

 	//Render the texture.

 	SDL_RenderCopy(texture,&texture_dimensions,&texture_dimensions);

 	SDL_RenderPresent();

 }

 static Uint32 next_time;

 Uint32 time_left() {

     Uint32 now = SDL_GetTicks();

     if(next_time <= now)

         return 0;

 	else

         return next_time - now;

 }

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

 	Uint8 num_pictures;

 	LoadedPicture* pictures;

 	int i, j;

 	SDL_PixelFormat* format = NULL;

 	SDL_Window *window;

 	SDL_Color black = {0,0,0,0xff};

 	SDL_Event event;

 	int event_pending = 0;

 	int should_exit = 0;

 	unsigned int current_picture;

 	int button_down;

 	Uint32 pixelFormat = 0;

 	int access = 0;

 	SDL_Rect texture_dimensions;;

 	if(argc < 2) {

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

     	exit(-1);

     }

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

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

 		exit(-2);

 	}

 	num_pictures = argc - 1;

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

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

 		pictures[i].surface = NULL;

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

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

 		if(pictures[i].surface == NULL) {

 			j = 0;

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

 				if(pictures[j].surface != NULL)

 					SDL_FreeSurface(pictures[j].surface);

 			free(pictures);

 			SDL_VideoQuit();

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

 			exit(-3);

 		}

 		format = pictures[i].surface->format;

 		if(format->Amask != 0) {

 			pictures[i].mode.mode = ShapeModeBinarizeAlpha;

 			pictures[i].mode.parameters.binarizationCutoff = 255;

 		}

 		else {

 			pictures[i].mode.mode = ShapeModeColorKey;

 			pictures[i].mode.parameters.colorKey = black;

 		}

 	}

 	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].surface);

 		free(pictures);

 		SDL_VideoQuit();

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

 		exit(-4);

 	}

 	if(SDL_CreateRenderer(window,-1,0) == -1) {

 		SDL_DestroyWindow(window);

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

 			SDL_FreeSurface(pictures[i].surface);

 		free(pictures);

 		SDL_VideoQuit();

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

 		exit(-5);

 	}

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

 		pictures[i].texture = NULL;

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

 		pictures[i].texture = SDL_CreateTextureFromSurface(0,pictures[i].surface);

 		if(pictures[i].texture == NULL) {

 			j = 0;

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

 				if(pictures[i].texture != NULL)

 					SDL_DestroyTexture(pictures[i].texture);

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

 				SDL_FreeSurface(pictures[i].surface);

 			free(pictures);

 			SDL_DestroyRenderer(window);

 			SDL_DestroyWindow(window);

 			SDL_VideoQuit();

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

 			exit(-6);

 		}

 	}

 	event_pending = 0;

 	should_exit = 0;

 	event_pending = SDL_PollEvent(&event);

 	current_picture = 0;

 	button_down = 0;

 	texture_dimensions.h = 0;

 	texture_dimensions.w = 0;

 	texture_dimensions.x = 0;

 	texture_dimensions.y = 0;

 	SDL_QueryTexture(pictures[current_picture].texture,(Uint32 *)&pixelFormat,(int *)&access,&texture_dimensions.w,&texture_dimensions.h);

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

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

 	next_time = SDL_GetTicks() + TICK_INTERVAL;

 	while(should_exit == 0) {

 		event_pending = SDL_PollEvent(&event);

 		if(event_pending == 1) {

 			if(event.type == SDL_KEYDOWN) {

 				button_down = 1;

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

 					should_exit = 1;

 			}

 			if(button_down && event.type == SDL_KEYUP) {

 				button_down = 0;

 				current_picture += 1;

 				if(current_picture >= num_pictures)

 					current_picture = 0;

 				SDL_QueryTexture(pictures[current_picture].texture,(Uint32 *)&pixelFormat,(int *)&access,&texture_dimensions.w,&texture_dimensions.h);

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

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

 			}

 			if(event.type == SDL_QUIT)

 				should_exit = 1;

 			event_pending = 0;

 		}

 		render(window,pictures[current_picture].texture,texture_dimensions);

 		SDL_Delay(time_left());

 		next_time += TICK_INTERVAL;

 	}

 	//Free the textures.

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

 		SDL_DestroyTexture(pictures[i].texture);

 	//Destroy the window.

 	SDL_DestroyWindow(window);

 	//Free the original surfaces backing the textures.

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

 		SDL_FreeSurface(pictures[i].surface);

 	free(pictures);

 	//Call SDL_VideoQuit() before quitting.

 	SDL_VideoQuit();

 	return 0;

 }