import ammonite.ops._

import mill._

import mill.define.{Input, Sources, Target}

import mill.scalajslib._

import mill.scalalib._

import mill.scalalib.publish._

import mill.util.Loose

import scala.language.postfixOps

object V {

  val fatags = "0.5-SNAPSHOT"

  val scalaJs = "0.6.26"

  val scala211 = "2.11.12"

  val scala212 = "2.12.8"

}

object D {

  val scalatags = ivy"com.lihaoyi::scalatags::0.6.7"

}

def camelCase(s: String): String = {

  def inner(l: List[Char]): List[Char] = l match {

    case '-' :: '-' :: c :: rest => c.toUpper :: inner(rest)

    case '-' :: c :: rest => c.toUpper :: inner(rest)

    case c :: rest => c :: inner(rest)

    case Nil => Nil

  }

  inner(s toList) mkString ""

}

trait Common extends CrossSbtModule with PublishModule {

  def publishVersion: Target[String] = V.fatags

  def pomSettings = PomSettings(

    description = "FontAwesome Scala DSL (tags)",

    organization = "net.tz",

    url = "https://bitbucket.org/tzeman/fatags",

    licenses = Seq(License.`Apache-2.0`),

    versionControl = VersionControl(developerConnection = Some(

      "ssh://hg@bitbucket.org/tzeman/fatags")),

    developers = Seq(

      Developer("tzeman", "Tomas Zeman", "")

    )

  )

  override def scalacOptions = T{Seq(

    "-deprecation",                      // Emit warning and location for usages of deprecated APIs.

    "-encoding", "utf-8",                // Specify character encoding used by source files.

    "-explaintypes",                     // Explain type errors in more detail.

    "-feature",                          // Emit warning and location for usages of features that should be imported explicitly.

    "-language:higherKinds",             // Allow higher-kinded types

    "-language:implicitConversions",     // Allow definition of implicit functions called views

    "-language:reflectiveCalls",

    "-language:postfixOps",

    "-unchecked",                        // Enable additional warnings where generated code depends on assumptions.

    "-Xcheckinit",                       // Wrap field accessors to throw an exception on uninitialized access.

    "-Xfuture",                          // Turn on future language features.

    "-target:jvm-1.8",

  )}

  def hgId: Input[String] = T.input {

    os.proc("hg", "id", "-i").call().out.string.trim

  }

  def hgNum: Input[String] = T.input {

    os.proc("hg", "id", "-n").call().out.string.trim

  }

  def hgTag: Input[Option[String]] = T.input {

    os.proc("hg", "id", "-t").call().out.string.trim.split(' ').headOption

  }

  override def ivyDeps: Target[Loose.Agg[Dep]] = Agg(D.scalatags)

  override def sources: Sources = T.sources{

    super.sources() :+ PathRef(millSourcePath / 'shared / 'src / 'main / 'scala)

  }

  // https://github.com/FortAwesome/Font-Awesome/raw/5.6.3/metadata/icons.json

  type IcoDef = (String, Set[String])

  def parseIcons: Target[List[IcoDef]] = T{

    ujson.read(os.read! pwd / "icons.json").obj.map(e => (e._1, e._2.obj("styles").arr.map(_.str).toSet)).toList

  }

  private def tpl(d: IcoDef): String = {

    val sym = d._1

    d._2.map {

      case "brands" =>  s"""      val ${camelCase(s"fab-$sym")}: T = fab("$sym")\n"""

      case "solid" =>   s"""      val ${camelCase(s"fas-$sym")}: T = fas("$sym")\n"""

      case "regular" => s"""      val ${camelCase(s"far-$sym")}: T = far("$sym")\n"""

    }.mkString

  }

  override def generatedSources: Sources = T.sources{

    val d = T.ctx().dest

    val icons = parseIcons()

    write(d / "generated.scala",

      s"""

        | package fontawesome.generic

        | import scalatags.generic._

        | class GenericFA[Builder, Output <: FragT, FragT](

        |   val bun: Bundle[Builder, Output, FragT]) {

        |

        |   import bun.all._

        |

        |   type T = FA[Builder, Output, FragT]

        |

        |   val faStack: Modifier = cls := "fa-stack fa-lg"

        |

        |   implicit val bundle: Bundle[Builder, Output, FragT] = bun

        |   implicit def fa2tag(x: T): TypedTag[Builder, Output, FragT] = x()

        |

        |   private def fab(w: String): T = FA(FaStyle.Brands, w)

        |   private def far(w: String): T = FA(FaStyle.Regular, w)

        |   private def fas(w: String): T = FA(FaStyle.Solid, w)

        |

        |   ${icons map tpl mkString}

        |

        | }

      """.stripMargin)

    d

  }

}

class JvmModule(val crossScalaVersion: String) extends Common

class JsModule(val crossScalaVersion: String) extends ScalaJSModule

  with Common {

  override def scalaJSVersion: Target[String] = V.scalaJs

}

object jvm extends Cross[JvmModule](V.scala211, V.scala212)

object js extends Cross[JsModule](V.scala211, V.scala212)

def publishLocal(): define.Command[Unit] = T.command{

  jvm(V.scala212).publishLocal()()

  js(V.scala212).publishLocal()()

  jvm(V.scala211).publishLocal()()

  js(V.scala211).publishLocal()()

}

object example extends ScalaModule with ScalaJSModule {

  override def scalaVersion: Target[String] = T{V.scala212}

  override def scalaJSVersion: Target[String] = V.scalaJs

  /* Ugly hack to prevent

   * "Referring to non-existent method fontawesome.generic.FA... error"

   */

  //override def moduleDeps: Seq[PublishModule] = Seq(js(V.scala212))

  override def ivyDeps: Target[Loose.Agg[Dep]] = Agg(D.scalatags)

  override def sources: Sources = T.sources{super.sources() ++ js(V.scala212).sources()}

  override def generatedSources = T{js(V.scala212).generatedSources()}

}

// vim: et ts=2 sw=2 syn=scala