Custom sbt prompt

prompt.sbt

//configure custom sbt prompt
ThisBuild / shellPrompt := { state =>
  val extracted = Project.extract(state)
  import extracted._

  /* COLOR DEFS
   * for ansi color codes refer to http://www.calmar.ws/vim/color-output.png 
   * and to https://misc.flogisoft.com/bash/tip_colors_and_formatting
   */
  type Color = Byte

  val fontFg = 15.toByte

  val scalaBg = 9.toByte
  val sbtBg = 6.toByte
  val projectBg = 33.toByte
  val separator = "\uE0B4"

  val bg = (code: Color) => s"\u001b[48;5;${code}m"
  val fg = (code: Color) => s"\u001b[38;5;${code}m"

  val no_bg = "\u001b[49m"
  val no_fg = "\u001b[39m"

  /* SECTION DEFS */
  def split(from: Color, to: Color) =
   fg(from) :: bg(to) :: separator :: fg(fontFg) :: Nil

  def end(from: Color) =
    fg(from) :: no_bg :: separator :: no_fg :: " " :: Nil

  def section(
    background: Color,
    content: List[String],
    foreground: Color = fontFg
  ): List[String] =
    bg(background) :: fg(foreground) :: content

  /* CONTENT DEFS */
  val scalaLogo = "\uE737"
  val sbtLogo = "sbt"
  val pad = " "
  val module = {
    val root = rootProject(currentRef.build)
    val current = currentRef.project
    if (root == current) current else s"[$root].$current"
  }
  val scalaV = scalaVersion.get(structure.data).getOrElse("")
  val sbtV = sbtVersion.get(structure.data).fold("")("-" + _ )
  val projectV = (currentRef / version).get(structure.data).fold("")("-" + _ )
  
  /* BUILD THE BAR */
  val scalaSection =
    section(
      scalaBg,
      content = pad :: scalaLogo :: pad :: scalaV :: Nil
    )
  val sbtSection =
    section(
      sbtBg,
      content = pad :: sbtLogo :: sbtV :: Nil
    )
  val projectSection =
    section(
      projectBg,
      content = pad :: module :: projectV :: Nil
    )

  List.concat(
    scalaSection
  , split(from = scalaBg, to = sbtBg)
  , section(sbtBg, pad :: "sbt" :: sbtV :: Nil)
  , split(from = sbtBg, to = projectBg)
  , section(projectBg, pad :: module :: projectV :: Nil)
  , end(from = projectBg)
  ).mkString

}

Separator fonts are done with nerd fonts