/*  Title:      Pure/PIDE/command.scala

    Author:     Fabian Immler, TU Munich

    Author:     Makarius

Prover commands with semantic state.

*/

package isabelle

import java.lang.System

import scala.collection.mutable

import scala.collection.immutable.SortedMap

object Command

{

  /** accumulated results from prover **/

  /* results */

  object Results

  {

    val empty = new Results(SortedMap.empty)

    def merge(rs: Iterable[Results]): Results = (empty /: rs.iterator)(_ ++ _)

  }

  final class Results private(rep: SortedMap[Long, XML.Tree])

  {

    def defined(serial: Long): Boolean = rep.isDefinedAt(serial)

    def get(serial: Long): Option[XML.Tree] = rep.get(serial)

    def entries: Iterator[(Long, XML.Tree)] = rep.iterator

    def + (entry: (Long, XML.Tree)): Results =

      if (defined(entry._1)) this

      else new Results(rep + entry)

    def ++ (other: Results): Results =

      if (this eq other) this

      else if (rep.isEmpty) other

      else (this /: other.entries)(_ + _)

    override def toString: String = entries.mkString("Results(", ", ", ")")

  }

  /* state */

  sealed case class State(

    command: Command,

    status: List[Markup] = Nil,

    results: Results = Results.empty,

    markup: Markup_Tree = Markup_Tree.empty)

  {

    def markup_to_XML(filter: XML.Elem => Boolean): XML.Body =

      markup.to_XML(command.range, command.source, filter)

    /* accumulate content */

    private def add_status(st: Markup): State = copy(status = st :: status)

    private def add_markup(m: Text.Markup): State = copy(markup = markup + m)

    def + (alt_id: Document.ID, message: XML.Elem): Command.State =

      message match {

        case XML.Elem(Markup(Markup.STATUS, _), msgs) =>

          (this /: msgs)((state, msg) =>

            msg match {

              case elem @ XML.Elem(markup, Nil) =>

                state.add_status(markup)

                  .add_markup(Text.Info(command.proper_range, elem))  // FIXME cumulation order!?

              case _ => System.err.println("Ignored status message: " + msg); state

            })

        case XML.Elem(Markup(Markup.REPORT, _), msgs) =>

          (this /: msgs)((state, msg) =>

            msg match {

              case XML.Elem(Markup(name, atts @ Position.Id_Range(id, raw_range)), args)

              if (id == command.id || id == alt_id) &&

                  command.range.contains(command.decode(raw_range)) =>

                val range = command.decode(raw_range)

                val props = Position.purge(atts)

                val info: Text.Markup = Text.Info(range, XML.Elem(Markup(name, props), args))

                state.add_markup(info)

              case XML.Elem(Markup(name, atts), args)

              if !atts.exists({ case (a, _) => Markup.POSITION_PROPERTIES(a) }) =>

                val range = command.proper_range

                val props = Position.purge(atts)

                val info: Text.Markup = Text.Info(range, XML.Elem(Markup(name, props), args))

                state.add_markup(info)

              case _ =>

                // FIXME System.err.println("Ignored report message: " + msg)

                state

            })

        case XML.Elem(Markup(name, atts), body) =>

          atts match {

            case Markup.Serial(i) =>

              val props = Position.purge(atts)

              val message1 = XML.Elem(Markup(Markup.message(name), props), body)

              val message2 = XML.Elem(Markup(name, props), body)

              val st0 = copy(results = results + (i -> message1))

              val st1 =

                if (Protocol.is_inlined(message))

                  (st0 /: Protocol.message_positions(command, message))(

                    (st, range) => st.add_markup(Text.Info(range, message2)))

                else st0

              st1

            case _ => System.err.println("Ignored message without serial number: " + message); this

          }

      }

  }

  /* make commands */

  type Span = List[Token]

  def apply(id: Document.Command_ID, node_name: Document.Node.Name, span: Span,

    results: Results = Results.empty, markup: Markup_Tree = Markup_Tree.empty): Command =

  {

    val source: String =

      span match {

        case List(tok) => tok.source

        case _ => span.map(_.source).mkString

      }

    val span1 = new mutable.ListBuffer[Token]

    var i = 0

    for (Token(kind, s) <- span) {

      val n = s.length

      val s1 = source.substring(i, i + n)

      span1 += Token(kind, s1)

      i += n

    }

    new Command(id, node_name, span1.toList, source, results, markup)

  }

  val empty = Command(Document.no_id, Document.Node.Name.empty, Nil)

  def unparsed(id: Document.Command_ID, source: String, results: Results, markup: Markup_Tree)

      : Command =

    Command(id, Document.Node.Name.empty, List(Token(Token.Kind.UNPARSED, source)), results, markup)

  def unparsed(source: String): Command =

    unparsed(Document.no_id, source, Results.empty, Markup_Tree.empty)

  def rich_text(id: Document.Command_ID, results: Results, body: XML.Body): Command =

  {

    val text = XML.content(body)

    val markup = Markup_Tree.from_XML(body)

    unparsed(id, text, results, markup)

  }

  /* perspective */

  object Perspective

  {

    val empty: Perspective = Perspective(Nil)

  }

  sealed case class Perspective(commands: List[Command])  // visible commands in canonical order

  {

    def same(that: Perspective): Boolean =

    {

      val cmds1 = this.commands

      val cmds2 = that.commands

      require(!cmds1.exists(_.is_undefined))

      require(!cmds2.exists(_.is_undefined))

      cmds1.length == cmds2.length &&

        (cmds1.iterator zip cmds2.iterator).forall({ case (c1, c2) => c1.id == c2.id })

    }

  }

}

final class Command private(

    val id: Document.Command_ID,

    val node_name: Document.Node.Name,

    val span: Command.Span,

    val source: String,

    val init_results: Command.Results,

    val init_markup: Markup_Tree)

{

  /* classification */

  def is_undefined: Boolean = id == Document.no_id

  val is_unparsed: Boolean = span.exists(_.is_unparsed)

  val is_unfinished: Boolean = span.exists(_.is_unfinished)

  val is_ignored: Boolean = !span.exists(_.is_proper)

  val is_malformed: Boolean = !is_ignored && (!span.head.is_command || span.exists(_.is_error))

  def is_command: Boolean = !is_ignored && !is_malformed

  def name: String =

    span.find(_.is_command) match { case Some(tok) => tok.source case _ => "" }

  override def toString =

    id + "/" + (if (is_command) name else if (is_ignored) "IGNORED" else "MALFORMED")

  /* source text */

  def length: Int = source.length

  val range: Text.Range = Text.Range(0, length)

  val proper_range: Text.Range =

    Text.Range(0, (length /: span.reverse.iterator.takeWhile(_.is_improper))(_ - _.source.length))

  def source(range: Text.Range): String = source.substring(range.start, range.stop)

  lazy val symbol_index = new Symbol.Index(source)

  def decode(i: Text.Offset): Text.Offset = symbol_index.decode(i)

  def decode(r: Text.Range): Text.Range = symbol_index.decode(r)

  /* accumulated results */

  val init_state: Command.State =

    Command.State(this, results = init_results, markup = init_markup)

}