package sbt

	import Types.const
	import complete.Parser
	import java.io.File
	import Scope.ThisScope
	import KeyRanks.{DTask, Invisible}

/** A concrete settings system that uses `sbt.Scope` for the scope type. */
object Def extends Init[Scope] with TaskMacroExtra
{
	type Classpath = Seq[Attributed[File]]

	val triggeredBy = AttributeKey[Seq[Task[_]]]("triggered-by")
	val runBefore = AttributeKey[Seq[Task[_]]]("run-before")
	val resolvedScoped = SettingKey[ScopedKey[_]]("resolved-scoped", "The ScopedKey for the referencing setting or task.", KeyRanks.DSetting)
	private[sbt] val taskDefinitionKey = AttributeKey[ScopedKey[_]]("task-definition-key", "Internal: used to map a task back to its ScopedKey.", Invisible)

	lazy val showFullKey: Show[ScopedKey[_]] = showFullKey(None)
	def showFullKey(keyNameColor: Option[String]): Show[ScopedKey[_]] =
		new Show[ScopedKey[_]] { def apply(key: ScopedKey[_]) = displayFull(key, keyNameColor) }

	def showRelativeKey(current: ProjectRef, multi: Boolean, keyNameColor: Option[String] = None): Show[ScopedKey[_]] = new Show[ScopedKey[_]] {
		def apply(key: ScopedKey[_]) =
			Scope.display(key.scope, colored(key.key.label, keyNameColor), ref => displayRelative(current, multi, ref))
	}
	def displayRelative(current: ProjectRef, multi: Boolean, project: Reference): String = project match {
		case BuildRef(current.build) => "{.}/"
		case `current` => if(multi) current.project + "/" else ""
		case ProjectRef(current.build, x) => x + "/"
		case _ => Reference.display(project) + "/"
	}
	def displayFull(scoped: ScopedKey[_]): String = displayFull(scoped, None)
	def displayFull(scoped: ScopedKey[_], keyNameColor: Option[String]): String = Scope.display(scoped.scope, colored(scoped.key.label, keyNameColor))
	def displayMasked(scoped: ScopedKey[_], mask: ScopeMask): String = Scope.displayMasked(scoped.scope, scoped.key.label, mask)

	def colored(s: String, color: Option[String]): String = color match {
		case Some(c) => c + s + scala.Console.RESET
		case None => s
	}

	override def deriveAllowed[T](s: Setting[T], allowDynamic: Boolean): Option[String] =
		super.deriveAllowed(s, allowDynamic) orElse
		(if(s.key.scope != ThisScope) Some(s"Scope cannot be defined for ${definedSettingString(s)}") else None ) orElse
		s.dependencies.find(k => k.scope != ThisScope).map(k => s"Scope cannot be defined for dependency ${k.key.label} of ${definedSettingString(s)}")

	private[this] def definedSettingString(s: Setting[_]): String =
		s"derived setting ${s.key.key.label}${positionString(s)}"
	private[this] def positionString(s: Setting[_]): String =
		s.positionString match { case None => ""; case Some(pos) => s" defined at $pos" }


	/** A default Parser for splitting input into space-separated arguments.
	* `argLabel` is an optional, fixed label shown for an argument during tab completion.*/
	def spaceDelimited(argLabel: String = "<arg>"): Parser[Seq[String]] = complete.Parsers.spaceDelimited(argLabel)

	/** Lifts the result of a setting initialization into a Task. */
	def toITask[T](i: Initialize[T]): Initialize[Task[T]] = map(i)(std.TaskExtra.inlineTask)

	def toSParser[T](p: Parser[T]): State => Parser[T] = const(p)
	def toISParser[T](p: Initialize[Parser[T]]): Initialize[State => Parser[T]] = p(toSParser)
	def toIParser[T](p: Initialize[InputTask[T]]): Initialize[State => Parser[Task[T]]] = p(_.parser)

		import language.experimental.macros
		import std.TaskMacro.{inputTaskMacroImpl, inputTaskDynMacroImpl, taskDynMacroImpl, taskMacroImpl}
		import std.SettingMacro.{settingDynMacroImpl,settingMacroImpl}
		import std.{InputEvaluated, MacroPrevious, MacroValue, MacroTaskValue, ParserInput}

	def task[T](t: T): Def.Initialize[Task[T]] = macro taskMacroImpl[T]
	def taskDyn[T](t: Def.Initialize[Task[T]]): Def.Initialize[Task[T]] = macro taskDynMacroImpl[T]
	def setting[T](t: T): Def.Initialize[T] = macro settingMacroImpl[T]
	def settingDyn[T](t: Def.Initialize[T]): Def.Initialize[T] = macro settingDynMacroImpl[T]
	def inputTask[T](t: T): Def.Initialize[InputTask[T]] = macro inputTaskMacroImpl[T]
	def inputTaskDyn[T](t: Def.Initialize[Task[T]]): Def.Initialize[InputTask[T]] = macro inputTaskDynMacroImpl[T]

	// The following conversions enable the types Initialize[T], Initialize[Task[T]], and Task[T] to
	//  be used in task and setting macros as inputs with an ultimate result of type T

	implicit def macroValueI[T](in: Initialize[T]): MacroValue[T] = ???
	implicit def macroValueIT[T](in: Initialize[Task[T]]): MacroValue[T] = ???
	implicit def macroValueIInT[T](in: Initialize[InputTask[T]]): InputEvaluated[T] = ???
	implicit def taskMacroValueIT[T](in: Initialize[Task[T]]): MacroTaskValue[T] = ???
	implicit def macroPrevious[T](in: TaskKey[T]): MacroPrevious[T] = ???

	// The following conversions enable the types Parser[T], Initialize[Parser[T]], and Initialize[State => Parser[T]] to
	//  be used in the inputTask macro as an input with an ultimate result of type T
	implicit def parserInitToInput[T](p: Initialize[Parser[T]]): ParserInput[T] = ???
	implicit def parserInitStateToInput[T](p: Initialize[State => Parser[T]]): ParserInput[T] = ???

		import language.experimental.macros
	def settingKey[T](description: String): SettingKey[T] = macro std.KeyMacro.settingKeyImpl[T]
	def taskKey[T](description: String): TaskKey[T] = macro std.KeyMacro.taskKeyImpl[T]
	def inputKey[T](description: String): InputKey[T] = macro std.KeyMacro.inputKeyImpl[T]

	private[sbt] def dummy[T: Manifest](name: String, description: String): (TaskKey[T], Task[T]) = (TaskKey[T](name, description, DTask), dummyTask(name))
	private[sbt] def dummyTask[T](name: String): Task[T] =
	{
		import std.TaskExtra.{task => newTask, _}
		val base: Task[T] = newTask( sys.error("Dummy task '" + name + "' did not get converted to a full task.") ) named name
		base.copy(info = base.info.set(isDummyTask, true))
	}
	private[sbt] def isDummy(t: Task[_]): Boolean = t.info.attributes.get(isDummyTask) getOrElse false
	private[sbt] val isDummyTask = AttributeKey[Boolean]("is-dummy-task", "Internal: used to identify dummy tasks.  sbt injects values for these tasks at the start of task execution.", Invisible)
	private[sbt] val (stateKey, dummyState) = dummy[State]("state", "Current build state.")
	private[sbt] val (streamsManagerKey, dummyStreamsManager) = Def.dummy[std.Streams[ScopedKey[_]]]("streams-manager", "Streams manager, which provides streams for different contexts.")
}
// these need to be mixed into the sbt package object because the target doesn't involve Initialize or anything in Def
trait TaskMacroExtra
{
	implicit def macroValueT[T](in: Task[T]): std.MacroValue[T] = ???
	implicit def macroValueIn[T](in: InputTask[T]): std.InputEvaluated[T] = ???
	implicit def parserToInput[T](in: Parser[T]): std.ParserInput[T] = ???
	implicit def stateParserToInput[T](in: State => Parser[T]): std.ParserInput[T] = ???
}