sbt-shell-prompt.sbt

//put in ~/.sbt/1.0/global.sbt if you want this to be the default shell everywhere

import scala.sys.process._
import scala.util.Try

shellPrompt := { s: State =>
  val extracted = Project.extract(s)

  val devNull = ProcessLogger(_ => ())

  val branchOp: Option[String] = Try(sys.process.Process("git rev-parse --abbrev-ref HEAD").!!(devNull)).
                                  map(_.replace("\n", "").replace("\r", "")).
                                  toOption
  (name in extracted.currentRef).get(extracted.structure.data) match {
    case Some(name) =>
      branchOp.fold(s"${RESET}${CYAN}${name}${RESET}> ")(branch =>
                    s"${RESET}${CYAN}${name}${RESET}:${RESET}${YELLOW}${BOLD}${branch}${RESET}> ")
    case _       => "> "
  }
}