UEFI Dialog with key event

/*
 * MENU DIALOG UEFI
 *
 */

void button_draw(const char* text, int x, int y, int w, int h) {
  word colorAccent = RGB(ff8800);
  /* draw text */
  LIBAROMA_TEXT textp = libaroma_text(
    text,
    colorAccent,
    w - libaroma_dp(16),
    LIBAROMA_FONT(1,4)|
    LIBAROMA_TEXT_SINGLELINE|
    LIBAROMA_TEXT_CENTER|
    LIBAROMA_TEXT_FIXED_INDENT|
    LIBAROMA_TEXT_FIXED_COLOR|
    LIBAROMA_TEXT_NOHR,
    100
  );
  int ty = y + (h>>1) - ((libaroma_text_height(textp)>>1));
  libaroma_text_draw(dc,textp,x + libaroma_dp(8),ty);
  libaroma_text_free(textp);
}
int button_width(const char* text) {
  /* draw text */
  LIBAROMA_TEXT textp = libaroma_text(
    text,
    0,
    dc->w,
    LIBAROMA_FONT(1,4)|
    LIBAROMA_TEXT_SINGLELINE|
    LIBAROMA_TEXT_CENTER|
    LIBAROMA_TEXT_FIXED_INDENT|
    LIBAROMA_TEXT_FIXED_COLOR|
    LIBAROMA_TEXT_NOHR,
    100
  );
  int w = libaroma_dp(8) + libaroma_text_width(textp) + libaroma_dp(8);
  libaroma_text_free(textp);
  return w;
}

int MenuShowDialog(
  const char * Title,
  const char * Message,
  const char * Button1,
  const char * Button2
){
  int Selection = 0;
  int MaxSelection = (Button1?1:0) + (Button2?1:0);


  /* COLORS */
  word colorTextSecondary = RGB(cccccc);
  word colorTextPrimary = RGB(ffffff);
  word colorBackground = RGB(444444);
  word colorSelection = RGB(aaaaaa);

  /*
    if(Initialized==FALSE)
      return -1;
    UINT32 OldMode = mGop->Mode->Mode;
    mGop->SetMode(mGop, gLKDisplay->GetPortraitMode());
  */

  /* Mask Dark */
  libaroma_draw_rect(
    dc, 0, 0, dc->w, dc->h, RGB(000000), 0x7a
  );

  /* Init Message & Title Text */
  int dialog_w = dc->w-libaroma_dp(48);
  LIBAROMA_TEXT messagetextp = libaroma_text(
    Message,
    colorTextSecondary,
    dialog_w-libaroma_dp(48),
    LIBAROMA_FONT(0,4)|
    LIBAROMA_TEXT_LEFT|
    LIBAROMA_TEXT_FIXED_INDENT|
    LIBAROMA_TEXT_FIXED_COLOR|
    LIBAROMA_TEXT_NOHR,
    100
  );
  LIBAROMA_TEXT textp = libaroma_text(
    Title,
    colorTextPrimary,
    dialog_w-libaroma_dp(48),
    LIBAROMA_FONT(1,6)|
    LIBAROMA_TEXT_LEFT|
    LIBAROMA_TEXT_FIXED_INDENT|
    LIBAROMA_TEXT_FIXED_COLOR|
    LIBAROMA_TEXT_NOHR,
    100
  );

  int dialog_h =
    libaroma_dp(120)+
    libaroma_text_height(textp)+
    libaroma_text_height(messagetextp);
  int dialog_x = libaroma_dp(24);
  int dialog_y = (dc->h>>1)-(dialog_h>>1);

  /* draw fake shadow */
  int z;
  int shadow_sz=libaroma_dp(2);
  byte shadow_opa = (byte) (0x60 / shadow_sz);
  for (z=1;z<shadow_sz;z++){
    int wp=z*2;
    libaroma_gradient_ex(dc,
      dialog_x-z, dialog_y+(z>>1),
      dialog_w+wp, dialog_h+wp,
      0,0,
      libaroma_dp(4),
      0x1111,
      shadow_opa, shadow_opa
    );
  }

  /* draw dialog */
  libaroma_gradient(dc,
    dialog_x, dialog_y,
    dialog_w, dialog_h,
    colorBackground,colorBackground,
    libaroma_dp(4), /* rounded 4dp */
    0x1111 /* all corners */
  );

  /* draw texts */
  libaroma_text_draw(
    dc,
    textp,
    dialog_x+libaroma_dp(24),
    dialog_y+libaroma_dp(24)
  );
  libaroma_text_free(textp);

  /* draw text */
  libaroma_text_draw(
    dc,
    messagetextp,
    dialog_x+libaroma_dp(24),
    dialog_y+libaroma_dp(24)+libaroma_text_height(textp) + libaroma_dp(20)
  );
  libaroma_text_free(messagetextp);


  /* MENU SELECTION */
  UINTN           WaitIndex;
  EFI_INPUT_KEY   Key;
  while(TRUE) {
    int button_y = dialog_y+dialog_h-libaroma_dp(52);

    /* clean button area */
    libaroma_draw_rect(dc, dialog_x, button_y, dialog_w, libaroma_dp(36), colorBackground, 0xff);

    if(Button1) {
      /* button1 */
      int button_w = button_width(Button1);
      int button_x = dialog_x+dialog_w-button_w-libaroma_dp(16);

      if(Selection==0) {
        libaroma_gradient_ex(dc,
          button_x,button_y,
          button_w, libaroma_dp(36),
          colorSelection,colorSelection,
          libaroma_dp(2), /* rounded 2dp */
          0x1111, /* all corners */
          0x40, 0x40 /* start & end alpha */
        );
      }
      button_draw(Button1, button_x, button_y-libaroma_dp(2), button_w, libaroma_dp(36));

      /* button2 */
      if(Button2) {
        button_w = button_width(Button2);
        button_x -= (libaroma_dp(8)+button_w);
        if(Selection==1) {
          libaroma_gradient_ex(dc,
            button_x,button_y,
            button_w, libaroma_dp(36),
            colorSelection,colorSelection,
            libaroma_dp(2), /* rounded 2dp */
            0x1111, /* all corners */
            0x40, 0x40 /* start & end alpha */
          );
        }
        button_draw(Button2, button_x, button_y-libaroma_dp(2), button_w, libaroma_dp(36));
      }
    }
    libaroma_sync();

    EFI_STATUS Status = gBS->WaitForEvent (1, &gST->ConIn->WaitForKey, &WaitIndex);
    ASSERT_EFI_ERROR (Status);

    Status = gST->ConIn->ReadKeyStroke (gST->ConIn, &Key);

    if(Key.ScanCode==SCAN_NULL) {
      switch(Key.UnicodeChar) {
        case CHAR_CARRIAGE_RETURN:
          RenderActiveMenu();
          mGop->SetMode(mGop, OldMode);
          return Selection;
      }
    }
    else {
      switch(Key.ScanCode) {
        case SCAN_UP:
          if(Selection>0)
            Selection--;
          else Selection = MaxSelection-1;
          break;
        case SCAN_DOWN:
          if(Selection+1<MaxSelection)
            Selection++;
          else Selection = 0;
          break;
      }
    }
  }
  return -1;
}