#include <SDL.h>
#include <SDL_image.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <errno.h>
#include <string.h>
#include <assert.h>
#include <time.h>
#include "kiss.h"

char *title = "SDL 17 - Mouse Events";
SDL_Window *window;
SDL_Renderer *renderer;
SDL_Texture *image;
int width, height;
int sel_x = -1, sel_y = -1;
int sel_solid = 0;
int need_clicks = 2;

bool quit = 0;
bool done = 0;
bool next = 0;

enum
{
   tiles_w = 4,
   tiles_h = 4
};

bool clicks[tiles_h][tiles_w];

int
texture_draw_ex(SDL_Texture *texture, SDL_Rect *clip, int x, int y, double zoom, double angle, SDL_RendererFlip flip, const SDL_Color *c)
{
   int status = -1;
   SDL_Rect target = { x, y, clip->w * zoom, clip->h * zoom };
   if (c)
     {
        SDL_SETTEXTURECOLORMOD(texture, c->r, c->g, c->b);
        SDL_SETTEXTUREALPHAMOD(texture, c->a);
     }
   SDL_RENDERCOPYEX(renderer, texture, clip, &target, angle, NULL, flip);
   if (c)
     {
        SDL_SETTEXTURECOLORMOD(texture, 0xFF, 0xFF, 0xFF);
        SDL_SETTEXTUREALPHAMOD(texture, 0xFF);
     }
   status = 0;
error:
   return status;
}

#define TEXTURE_DRAW_EX(...) SDL_ZERO(texture_draw_ex, __VA_ARGS__)

int
draw(void)
{
   int status = -1;
   int x, y;

   int done1 = 1;

   SDL_SetRenderDrawColor(renderer, 0x7F, 0x7F, 0x7F, 0xFF);
   SDL_RENDERCLEAR(renderer);

   for (y = 0; y < tiles_h; ++y)
     {
        for (x = 0; x < tiles_w; ++x)
          {
             int xp = width * x / tiles_w;
             int yp = height * y / tiles_h;
             int xp1 = width * (x + 1) / tiles_w;
             int yp1 = height * (y + 1) / tiles_h;
             int c = clicks[y][x];
             SDL_Rect clip = { xp, yp, xp1 - xp, yp1 - yp };

             if (x == sel_x && y == sel_y)
               {
                  if (sel_solid)
                    {
                       SDL_SetRenderDrawColor(renderer, 0xFF, 0x7F, 0x3F, 0xFF);
                       SDL_RENDERFILLRECT(renderer, &clip);
                    }
                  else
                    {
                       SDL_SetRenderDrawColor(renderer, 0x00, 0x00, 0x00, 0xFF);
                       SDL_RENDERDRAWRECT(renderer, &clip);
                    }
               }
             if (c > need_clicks)
               {
                  c = clicks[y][x] = 0;
               }
             if (c < need_clicks)
               {
                  done1 = 0;
               }
             if (c)
               {
                  int a = 0xFF * c / need_clicks;
                  TEXTURE_DRAW_EX(image, &clip, xp, yp, 1, 0, 0, &(SDL_Color){0xFF, 0xFF, 0xFF, a });
               }
          }
     }
   SDL_RenderPresent(renderer);
   done = done1;
   status = 0;
error:
   return status;
}

#define DRAW(...) SDL_ZERO(draw, __VA_ARGS__)

bool changed = 1;

void
mouse_event(SDL_Event *e)
{
   int x, y;

   if (e->type == SDL_MOUSEMOTION)
     {
        x = e->motion.x * tiles_w / width;
        y = e->motion.y * tiles_h / height;
        if (x != sel_x || y != sel_y)
          {
             sel_x = x;
             sel_y = y;
             sel_solid = 0;
             changed = 1;
          }
     }
   else if (e->type == SDL_MOUSEBUTTONDOWN || e->type == SDL_MOUSEBUTTONUP)
     {
        x = e->button.x * tiles_w / width;
        y = e->button.y * tiles_h / height;
        if (x >= 0 && x < tiles_w && y >= 0 && y < tiles_h)
          {
             if (e->type == SDL_MOUSEBUTTONUP)
               {
                  clicks[y][x]++;
                  sel_x = -1;
                  sel_y = -1;
               }
             else
               {
                  sel_x = x;
                  sel_y = y;
                  sel_solid = 1;
               }
             changed = 1;
          }
     }
//        buttons = SDL_GetMouseState(&x, &y);
}

void
key_down(SDL_Keycode k)
{
   switch (k)
     {
      case SDLK_SPACE:
        if (done)
          next = 1;
        break;

      case SDLK_ESCAPE:
        next = 1;
        break;
     }
}

int
play(char *image_file)
{
   int status = -1;
   SDL_Event e;
   SDL_Surface *surface = NULL;

   done = 0;
   next = 0;
   changed = 1;

   memset(clicks, 0, sizeof(clicks));

   surface = IMG_LOAD(image_file);
   width = surface->w;
   height = surface->h;
   window = SDL_CREATEWINDOW(title, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, width, height, 0);
   renderer = SDL_CREATERENDERER(window, -1, SDL_RENDERER_ACCELERATED);
   image = SDL_CREATETEXTUREFROMSURFACE(renderer, surface);
   SDL_FREESURFACE(surface);
   SDL_SETTEXTUREBLENDMODE(image, SDL_BLENDMODE_BLEND);

   while (!quit && !next)
     {
        if (changed)
          {
             DRAW();
             changed = 0;
          }
        SDL_WaitEvent(&e);
        if (e.type == SDL_QUIT)
          quit = 1;
        if (e.type == SDL_MOUSEMOTION || e.type == SDL_MOUSEBUTTONDOWN || e.type == SDL_MOUSEBUTTONUP)
          mouse_event(&e);
        if (e.type == SDL_KEYDOWN)
          key_down(e.key.keysym.sym);
     }

   status = 0;
error:
   SDL_DESTROYTEXTURE(image);
   SDL_DESTROYRENDERER(renderer);
   SDL_DESTROYWINDOW(window);
   SDL_FREESURFACE(surface);
   return status;
}

#define PLAY(...) SDL_ZERO(play, __VA_ARGS__)

int
main(int argc, char *argv[])
{
   int exit_status = EXIT_FAILURE;

   --argc; ++argv;

   srand((unsigned)time(NULL));

   SDL_INIT(SDL_INIT_VIDEO);
   IMG_INIT(IMG_INIT_PNG | IMG_INIT_JPG);

   while (!quit)
     {
        char *image_file = "cat.jpg";
        if (argc > 0)
          {
             int i = rand() % argc;
             image_file = argv[i];
             for (; i <= argc; ++i)
               argv[i] = argv[i + 1];
             --argc;
          }
        PLAY(image_file);
     }

   exit_status = EXIT_SUCCESS;
error:
   IMG_Quit();
   SDL_Quit();
   exit(exit_status);
}