src/Tools/VSCode/src/document_model.scala

incremental document changes;

/*  Title:      Tools/VSCode/src/document_model.scala
    Author:     Makarius

Document model for line-oriented text.
*/

package isabelle.vscode


import isabelle._

import java.io.{File => JFile}


object Document_Model
{
  /* decorations */

  object Decoration
  {
    def empty(typ: String): Decoration = Decoration(typ, Nil)

    def ranges(typ: String, ranges: List[Text.Range]): Decoration =
      Decoration(typ, ranges.map(Text.Info(_, List.empty[XML.Body])))
  }
  sealed case class Decoration(typ: String, content: List[Text.Info[List[XML.Body]]])


  /* content */

  sealed case class Content(doc: Line.Document)
  {
    def text_range: Text.Range = doc.text_range
    def text: String = doc.text
    def try_get_text(range: Text.Range): Option[String] = doc.try_get_text(range)

    lazy val bytes: Bytes = Bytes(text)
    lazy val chunk: Symbol.Text_Chunk = Symbol.Text_Chunk(text)
    lazy val bibtex_entries: List[Text.Info[String]] =
      try { Bibtex.document_entries(text) }
      catch { case ERROR(_) => Nil }
  }

  def init(session: Session, node_name: Document.Node.Name): Document_Model =
  {
    val resources = session.resources.asInstanceOf[VSCode_Resources]
    val content = Content(Line.Document("", resources.text_length))
    Document_Model(session, node_name, content)
  }
}

sealed case class Document_Model(
  session: Session,
  node_name: Document.Node.Name,
  content: Document_Model.Content,
  external_file: Boolean = false,
  node_required: Boolean = false,
  last_perspective: Document.Node.Perspective_Text = Document.Node.no_perspective_text,
  pending_edits: List[Text.Edit] = Nil,
  published_diagnostics: List[Text.Info[Command.Results]] = Nil,
  published_decorations: List[Document_Model.Decoration] = Nil) extends Document.Model
{
  /* external file */

  def external(b: Boolean): Document_Model = copy(external_file = b)

  def node_visible: Boolean = !external_file


  /* header */

  def node_header: Document.Node.Header =
    resources.special_header(node_name) getOrElse
      resources.check_thy_reader("", node_name, Scan.char_reader(content.text))


  /* perspective */

  def node_perspective(doc_blobs: Document.Blobs): (Boolean, Document.Node.Perspective_Text) =
  {
    if (is_theory) {
      val snapshot = this.snapshot()

      val text_perspective =
        if (node_visible || snapshot.commands_loading_ranges(resources.visible_node(_)).nonEmpty)
          Text.Perspective.full
        else Text.Perspective.empty

      (snapshot.node.load_commands_changed(doc_blobs),
        Document.Node.Perspective(node_required, text_perspective, Document.Node.Overlays.empty))
    }
    else (false, Document.Node.no_perspective_text)
  }


  /* blob */

  def get_blob: Option[Document.Blob] =
    if (is_theory) None
    else Some((Document.Blob(content.bytes, content.chunk, pending_edits.nonEmpty)))


  /* edits */

  def change_text(text: String, range: Option[Line.Range] = None): Option[Document_Model] =
  {
    val insert = Line.normalize(text)
    range match {
      case None =>
        Text.Edit.replace(0, content.text, insert) match {
          case Nil => None
          case edits =>
            val content1 = Document_Model.Content(Line.Document(insert, content.doc.text_length))
            Some(copy(content = content1, pending_edits = pending_edits ::: edits))
        }
      case Some(remove) =>
        content.doc.change(remove, insert) match {
          case None => error("Failed to apply document change: " + remove)
          case Some((Nil, _)) => None
          case Some((edits, doc1)) =>
            val content1 = Document_Model.Content(doc1)
            Some(copy(content = content1, pending_edits = pending_edits ::: edits))
        }
    }
  }

  def flush_edits(doc_blobs: Document.Blobs): Option[(List[Document.Edit_Text], Document_Model)] =
  {
    val (reparse, perspective) = node_perspective(doc_blobs)
    if (reparse || pending_edits.nonEmpty || last_perspective != perspective) {
      val edits = node_edits(node_header, pending_edits, perspective)
      Some((edits, copy(pending_edits = Nil, last_perspective = perspective)))
    }
    else None
  }


  /* publish annotations */

  def publish(rendering: VSCode_Rendering):
    (Option[List[Text.Info[Command.Results]]], Option[List[Document_Model.Decoration]], Document_Model) =
  {
    val diagnostics = rendering.diagnostics
    val decorations =
      if (node_visible) rendering.decorations
      else { for (deco <- published_decorations) yield Document_Model.Decoration.empty(deco.typ) }

    val changed_diagnostics =
      if (diagnostics == published_diagnostics) None else Some(diagnostics)
    val changed_decorations =
      if (decorations == published_decorations) None
      else if (published_decorations.isEmpty) Some(decorations)
      else Some(for { (a, b) <- decorations zip published_decorations if a != b } yield a)

    (changed_diagnostics, changed_decorations,
      copy(published_diagnostics = diagnostics, published_decorations = decorations))
  }


  /* prover session */

  def resources: VSCode_Resources = session.resources.asInstanceOf[VSCode_Resources]

  def is_stable: Boolean = pending_edits.isEmpty
  def snapshot(): Document.Snapshot = session.snapshot(node_name, pending_edits)

  def rendering(): VSCode_Rendering = new VSCode_Rendering(this, snapshot(), resources)
}