RGB Terminal Colors with Haskell and Brick - haskell

Question

I know that the Brick and the VTY hackage do not support escape sequences. VTY only supports 240 colors.
Is there any workaround to use true RGB colors and not mess up the layout?
This is an example I made, but I can't get the border right:
module BrickTest where
import Brick (simpleMain, Widget, str)
import Brick.Widgets.Border (border)
import Text.Printf (printf)
main :: IO ()
main = simpleMain $ colorWidget (255, 0, 0)
type RGB = (Int, Int, Int)
colorWidget :: RGB -> Widget ()
colorWidget (r, g, b) = border $ str (prefix ++ "a" ++ postfix)
where
prefix = printf "\ESC[38;2;%d;%d;%dm" r g b
postfix = "\ESC[0m"
output:
┌──────────────────┐
│a│
└──────────────────┘

Answer 1

I found a workaround. I managed to implement a function zeroWidthStr that can print any string, and Brick handles it as if it has width 0. But I can't really explain how this is working internally, and it might have some other side effects.
module BrickTest where
import Brick (Widget, raw, simpleMain, str,
(<+>))
import Brick.Widgets.Border (border)
import Data.List (intercalate)
import Data.Text.Lazy (pack)
import Graphics.Vty (defAttr)
import Graphics.Vty.Image.Internal (Image (HorizText))
import Text.Printf (printf)
main :: IO ()
main = simpleMain $ colorWidget (255, 0, 0)
type RGB = (Int, Int, Int)
colorWidget :: RGB -> Widget ()
colorWidget (r, g, b) = border $ prefix <+> str "a" <+> postfix
where
prefix = zeroWidthStr $ printf "\ESC[38;2;%d;%d;%dm" r g b
postfix = zeroWidthStr $ "\ESC[0m"
zeroWidthStr :: String -> Widget ()
-- | workaround to print any string in terminal, and hackage Brick (vty) handles it as if it has width 0
zeroWidthStr str = raw image
where
image = HorizText defAttr (pack modStr) 0 0
modStr = str ++ repeatN "\ESC\ESCa" (length str)
repeatN :: String -> Int -> String
repeatN str n = intercalate "" $ take n $ repeat str
output: