/*  Title:      Pure/PIDE/isar_document.scala

    Author:     Makarius

Protocol message formats for interactive Isar documents.

*/

package isabelle

object Isar_Document

{

  /* document editing */

  object Assign {

    def unapply(msg: XML.Tree)

        : Option[(Document.Version_ID, List[(Document.Command_ID, Document.Exec_ID)])] =

      msg match {

        case XML.Elem(Markup(Markup.ASSIGN, List((Markup.VERSION, Document.ID(id)))), edits) =>

          val id_edits = edits.map(Edit.unapply)

          if (id_edits.forall(_.isDefined)) Some((id, id_edits.map(_.get)))

          else None

        case _ => None

      }

  }

  object Edit {

    def unapply(msg: XML.Tree): Option[(Document.Command_ID, Document.Exec_ID)] =

      msg match {

        case XML.Elem(

          Markup(Markup.EDIT,

            List((Markup.ID, Document.ID(i)), (Markup.EXEC, Document.ID(j)))), Nil) => Some((i, j))

        case _ => None

      }

  }

  /* toplevel transactions */

  sealed abstract class Status

  case class Forked(forks: Int) extends Status

  case object Unprocessed extends Status

  case object Finished extends Status

  case object Failed extends Status

  def command_status(markup: List[Markup]): Status =

  {

    val forks = (0 /: markup) {

      case (i, Markup(Markup.FORKED, _)) => i + 1

      case (i, Markup(Markup.JOINED, _)) => i - 1

      case (i, _) => i

    }

    if (forks != 0) Forked(forks)

    else if (markup.exists(_.name == Markup.FAILED)) Failed

    else if (markup.exists(_.name == Markup.FINISHED)) Finished

    else Unprocessed

  }

  /* result messages */

  def clean_message(body: XML.Body): XML.Body =

    body filter { case XML.Elem(Markup(Markup.NO_REPORT, _), _) => false case _ => true } map

      { case XML.Elem(markup, ts) => XML.Elem(markup, clean_message(ts)) case t => t }

  def message_reports(msg: XML.Tree): List[XML.Elem] =

    msg match {

      case elem @ XML.Elem(Markup(Markup.REPORT, _), _) => List(elem)

      case XML.Elem(_, body) => body.flatMap(message_reports)

      case XML.Text(_) => Nil

    }

  /* specific messages */

  def is_ready(msg: XML.Tree): Boolean =

    msg match {

      case XML.Elem(Markup(Markup.STATUS, _),

        List(XML.Elem(Markup(Markup.READY, _), _))) => true

      case _ => false

    }

 def is_tracing(msg: XML.Tree): Boolean =

    msg match {

      case XML.Elem(Markup(Markup.TRACING, _), _) => true

      case _ => false

    }

  def is_warning(msg: XML.Tree): Boolean =

    msg match {

      case XML.Elem(Markup(Markup.WARNING, _), _) => true

      case _ => false

    }

  def is_error(msg: XML.Tree): Boolean =

    msg match {

      case XML.Elem(Markup(Markup.ERROR, _), _) => true

      case _ => false

    }

  def is_state(msg: XML.Tree): Boolean =

    msg match {

      case XML.Elem(Markup(Markup.WRITELN, _),

        List(XML.Elem(Markup(Markup.STATE, _), _))) => true

      case _ => false

    }

  /* reported positions */

  private val include_pos =

    Set(Markup.BINDING, Markup.ENTITY, Markup.REPORT, Markup.POSITION)

  def message_positions(command: Command, message: XML.Elem): Set[Text.Range] =

  {

    def positions(set: Set[Text.Range], tree: XML.Tree): Set[Text.Range] =

      tree match {

        case XML.Elem(Markup(name, Position.Id_Range(id, raw_range)), body)

        if include_pos(name) && id == command.id =>

          val range = command.decode(raw_range).restrict(command.range)

          body.foldLeft(if (range.is_singularity) set else set + range)(positions)

        case XML.Elem(Markup(name, _), body) => body.foldLeft(set)(positions)

        case _ => set

      }

    val set = positions(Set.empty, message)

    if (set.isEmpty && !is_state(message))

      set ++ Position.Range.unapply(message.markup.properties).map(command.decode(_))

    else set

  }

}

trait Isar_Document extends Isabelle_Process

{

  /* commands */

  def define_command(id: Document.Command_ID, text: String): Unit =

    input("Isar_Document.define_command", Document.ID(id), text)

  /* document versions */

  def edit_version(old_id: Document.Version_ID, new_id: Document.Version_ID,

    edits: List[Document.Edit_Command])

  {

    val edits_yxml =

    { import XML.Encode._

      def id: T[Command] = (cmd => long(cmd.id))

      def encode: T[List[Document.Edit_Command]] =

        list(pair(string,

          variant(List(

            { case Document.Node.Clear() => (Nil, Nil) },

            { case Document.Node.Edits(a) => (Nil, list(pair(option(id), option(id)))(a)) },

            { case Document.Node.Header(Exn.Res(Thy_Header(a, b, c))) =>

                (Nil, triple(string, list(string), list(pair(string, bool)))(a, b, c)) },

            { case Document.Node.Header(Exn.Exn(e)) => (List(Exn.message(e)), Nil) }))))

      YXML.string_of_body(encode(edits)) }

    input("Isar_Document.edit_version", Document.ID(old_id), Document.ID(new_id), edits_yxml)

  }

  /* method invocation service */

  def invoke_scala(id: String, tag: Invoke_Scala.Tag.Value, res: String)

  {

    input("Isar_Document.invoke_scala", id, tag.toString, res)

  }

}