// x-run: make run
#include <assert.h>
#include <raylib.h>
#include <stdio.h>
#include <stdlib.h>
#include <xcb/xcb.h>
#include <xcb/xproto.h>
#include <xcb/composite.h>


Image get_screenshot(xcb_connection_t *conn, xcb_window_t wid);

int main(int argc, char **argv) {
  xcb_connection_t *xcb = xcb_connect(NULL, NULL);

  SetConfigFlags(FLAG_WINDOW_TRANSPARENT);
  InitWindow(0, 0, "img/scrall");


  Image screenshot = get_screenshot(xcb, 50331654);
  assert(screenshot.width > 0);

  Texture2D screenshot_tex = LoadTextureFromImage(screenshot);
  SetWindowSize(screenshot.width, screenshot.height);

  while (!WindowShouldClose()) {
    BeginDrawing();
    ClearBackground(BLANK);
    DrawTexture(screenshot_tex, 0, 0, WHITE);
    EndDrawing();
  }
}

Image get_screenshot(xcb_connection_t *conn, xcb_window_t wid) {
  xcb_generic_error_t *err = NULL;

  xcb_composite_redirect_window(conn, wid, XCB_COMPOSITE_REDIRECT_AUTOMATIC);

  xcb_get_geometry_cookie_t gg_cookie = xcb_get_geometry(conn, wid);
  xcb_get_geometry_reply_t *gg_reply = xcb_get_geometry_reply(conn, gg_cookie, &err);

  if (!gg_reply) {
    fprintf(stderr, "xcb: error: geometry: %d\n", err->error_code);
    return (Image){
      .data = err, .width = 0, .height = 0, .format = 0, .mipmaps = 0
    };
  }

  int win_w = gg_reply->width;
  int win_h = gg_reply->height;
  assert(gg_reply->depth == 32);
  fprintf(stderr, "width: %d\nheight: %d\n", win_w, win_h);

  free(gg_reply);

  xcb_pixmap_t win_pixmap = xcb_generate_id(conn);
  xcb_composite_name_window_pixmap(conn, wid, win_pixmap);

  xcb_get_image_cookie_t gi_cookie = xcb_get_image(conn, XCB_IMAGE_FORMAT_Z_PIXMAP, win_pixmap, 0, 0, win_w, win_h, (uint32_t)(~0UL));
  xcb_get_image_reply_t *gi_reply = xcb_get_image_reply(conn, gi_cookie, &err);
  if (!gi_reply) {
    fprintf(stderr, "xcb: error: get_image_reply: %d\n", err->error_code);
    return (Image){
      .data = err, .width = 0, .height = 0, .format = 0, .mipmaps = 0
    };
  }

  int data_len = xcb_get_image_data_length(gi_reply);
  fprintf(stderr, "data_len: %d\n", data_len);

  uint8_t *data = xcb_get_image_data(gi_reply);

  Image img = GenImageColor(win_w, win_h, BLANK);

  for (int i = 0; i < data_len; i += 4) {
    ((uint8_t *)img.data)[i + 0] = data[i + 2];
    ((uint8_t *)img.data)[i + 1] = data[i + 1];
    ((uint8_t *)img.data)[i + 2] = data[i + 0];
    ((uint8_t *)img.data)[i + 3] = data[i + 3];
  }

  free(gi_reply);

  return img;
}