script.scala

#!/usr/bin/env sbt -Dsbt.version=1.4.7 -Dsbt.main.class=sbt.ScriptMain -Dsbt.supershell=false -error 
/***
// $ chmod +x scripts.scala
// $ ./scripts.scala
ThisBuild / scalaVersion := "2.13.4"
libraryDependencies += "org.scala-sbt" %% "io" % "1.4.0"
*/

import sbt.io._
import sbt.io.syntax._
import java.io.File
import java.net.{URI, URL}
import sys.process._
def file(s: String): File = new File(s)
def uri(s: String): URI = new URI(s)
def stdinStr = IO.readStream(System.in)

def removeRole(role: String): String => String =
  _.replaceAll("""(:""" + role + """:)(\`[^`]+\`)""", """$2""")
def nTicks(n: Int): String = """(\`{""" + n.toString + """})"""
def toSingleTicks: String => String = 
  _.replaceAll(nTicks(2), "`")
def toDoubleTicks: String => String =
  _.replaceAll(nTicks(1), "``")
val preprocessRest: String => String =
  removeRole("doc") andThen removeRole("key") andThen removeRole("ref") andThen toSingleTicks andThen toDoubleTicks
val isVerboseLine: String => Boolean = _.startsWith("  ")

val processLine: String => String = {
  case s if isVerboseLine(s) => identity(s)
  case s => preprocessRest(s)
}

def runPandoc(f: File): Seq[String] =
  Process(Seq("pandoc", "-f", "rst", "-t", "markdown", f.toString)).lazyLines.toVector

val outDir = file("./target/")
val srcDir = file("./src/")
val toOut = Path.rebase(srcDir, outDir)

def processFile(f: File): Unit = {
  val (base, ext) = f.baseAndExt
  val newParent = toOut(f.getParentFile) getOrElse {sys.error("wat")}
  val file1 = newParent / (base + "." + ext)
  val file2 = newParent / (base + ".md")
  println(s"""$f => $file2""")
  val xs = IO.readLines(f) map { processLine }
  IO.writeLines(file1, xs)
  val mdLines = runPandoc(file1)
  IO.delete(file1)
  IO.writeLines(file2, mdLines)
}

IO.createDirectory(outDir / "sphinx")
val fs: Seq[File] = (srcDir ** "*.rst").get()
fs foreach { processFile }