(ffi:clines "
#include <SDL2/SDL.h>

SDL_Renderer *renderer;
SDL_Window *window;
SDL_Event e;

const Uint8 *state;

int mx, my; Uint32 mdown;
int quitted;
")

(Defpackage "jam-no-theme" (:use cl) (:nicknames :ja))

(in-package :ja)


(defmacro game ((&rest shared-vars) 
                (&rest shared-declares) 
                update-closures)
 `(let ,shared-vars
   ,(append '(declare) shared-declares)
   (ffi:c-progn ,(mapcar 'car shared-vars)
    "

if (SDL_Init(SDL_INIT_VIDEO) < 0) {
	SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, 
	    \"Failed to init %s\",
	    SDL_GetError());
	" (error "failed to SDL_Init(video)") "
}

if (SDL_CreateWindowAndRenderer(640,480,SDL_WINDOW_RESIZABLE,
	&window, &renderer)) {
	SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, 
	    \"Failed to create w & r%s\",
	    SDL_GetError());
	" (error "failed to create window and renderer") "
}

quitted = 0;
for (;;) {"
	"
	while(SDL_PollEvent(&e))
	    if (e.type == SDL_QUIT) quitted = 1;
	    else if (e.type == SDL_KEYDOWN)
	        switch (e.key.keysym.sym) {
	        case SDLK_q:
	            quitted = 1;
	            break;
	        }
	if (quitted) break;

	mdown = SDL_GetMouseState(&mx, &my);
	"
	"
	SDL_SetRenderDrawColor(renderer, 0, 10, 20, 255);
	SDL_RenderClear(renderer);"

        (mapcar 'funcall ,update-closures)

	"
	SDL_RenderPresent(renderer);
	SDL_Delay(25);
	"
"}

SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();")))

(defun coord-liner (start-x below-x x-space
                     y-start y-stop y-space &key (transpose nil)
                     &aux (cur-x start-x)) "
(coord-liner (start-x below-x x-space
              y-start y-stop y-space 
              &key (transpose nil)))
Return a closure that returns 
(x1 y1 x2 y2) or nil when it loops, 
or if transpose (y1 x1 y2 x2)
"
 (lambda ()
  (reduce 'append
   (mapcar (if transpose 'reverse 'identity)
    (if (< cur-x below-x)
     (prog1 (list (list (* cur-x x-space) (* y-start y-space))
                  (list (* cur-x x-space) (* y-stop y-space)))
      (incf cur-x))
     (prog1 nil (setf cur-x start-x)))))))

(defun draw-lines-from (fun rgb) "
Calls SDL_SetRenderDrawColor and
      SDL_RenderDrawLine
with rgb and on a list from fun.
"
 (lambda ()
  (loop
   for (x1 y1 x2 y2) = (funcall fun)
   for (r g b) = rgb
   while x1
   do (ffi:c-inline (r g b 255) (:int :int :int :int) nil
       "SDL_SetRenderDrawColor(renderer, #0, #1, #2, #3)"
       :one-liner t)
   do (ffi:c-inline (x1 y1 x2 y2)
       (:int :int :int :int) nil
       "SDL_RenderDrawLine(renderer, #0, #1, #2, #3)"
       :one-liner t))))

(defun xs&+s () "
I was thinking of naughts and crosses, but ultimately
I'm just drawing a grid.
"
 (let* ((horiz-lines 
          (draw-lines-from
          (coord-liner 1 5 50 1 4 50 :transpose nil) 
          '(255 0 0)))
        (verti-lines 
         (draw-lines-from
          (coord-liner 1 5 50 1 4 50 :transpose t) 
          '(255 255 0)))
        (funs (list horiz-lines verti-lines)))
  (game () () funs)))