src/Tools/jEdit/src/jedit/document_view.scala

simplified/clarified Document_View.text_area_extension;
tuned Document.Node.block_size, trading some space for better time;

/*  Title:      Tools/jEdit/src/jedit/document_view.scala
    Author:     Fabian Immler, TU Munich
    Author:     Makarius

Document view connected to jEdit text area.
*/

package isabelle.jedit


import isabelle._

import scala.actors.Actor._

import java.awt.event.{MouseAdapter, MouseEvent}
import java.awt.{BorderLayout, Graphics, Dimension, Color, Graphics2D}
import javax.swing.{JPanel, ToolTipManager}
import javax.swing.event.{CaretListener, CaretEvent}

import org.gjt.sp.jedit.gui.RolloverButton
import org.gjt.sp.jedit.textarea.{JEditTextArea, TextArea, TextAreaExtension, TextAreaPainter}
import org.gjt.sp.jedit.syntax.SyntaxStyle


object Document_View
{
  def choose_color(snapshot: Document.Snapshot, command: Command): Color =
  {
    val state = snapshot.state(command)
    if (snapshot.is_outdated) new Color(240, 240, 240)
    else
      Isar_Document.command_status(state.status) match {
        case Isar_Document.Forked(i) if i > 0 => new Color(255, 228, 225)
        case Isar_Document.Finished => new Color(234, 248, 255)
        case Isar_Document.Failed => new Color(255, 193, 193)
        case Isar_Document.Unprocessed => new Color(255, 228, 225)
        case _ => Color.red
      }
  }


  /* document view of text area */

  private val key = new Object

  def init(model: Document_Model, text_area: TextArea): Document_View =
  {
    Swing_Thread.require()
    val doc_view = new Document_View(model, text_area)
    text_area.putClientProperty(key, doc_view)
    doc_view.activate()
    doc_view
  }

  def apply(text_area: TextArea): Option[Document_View] =
  {
    Swing_Thread.require()
    text_area.getClientProperty(key) match {
      case doc_view: Document_View => Some(doc_view)
      case _ => None
    }
  }

  def exit(text_area: TextArea)
  {
    Swing_Thread.require()
    apply(text_area) match {
      case None => error("No document view for text area: " + text_area)
      case Some(doc_view) =>
        doc_view.deactivate()
        text_area.putClientProperty(key, null)
    }
  }
}


class Document_View(val model: Document_Model, text_area: TextArea)
{
  private val session = model.session


  /* extended token styles */

  private var styles: Array[SyntaxStyle] = null  // owned by Swing thread

  def extend_styles()
  {
    Swing_Thread.require()
    styles = Document_Model.Token_Markup.extend_styles(text_area.getPainter.getStyles)
  }
  extend_styles()

  def set_styles()
  {
    Swing_Thread.require()
    text_area.getPainter.setStyles(styles)
  }


  /* commands_changed_actor */

  private val commands_changed_actor = actor {
    loop {
      react {
        case Session.Commands_Changed(changed) =>
          val buffer = model.buffer
          Isabelle.swing_buffer_lock(buffer) {
            val snapshot = model.snapshot()
            if (changed.exists(snapshot.node.commands.contains)) {
              var visible_change = false
              for ((command, start) <- snapshot.node.command_starts) {
                if (changed(command)) {
                  val stop = start + command.length
                  val line1 = buffer.getLineOfOffset(snapshot.convert(start))
                  val line2 = buffer.getLineOfOffset(snapshot.convert(stop))
                  if (line2 >= text_area.getFirstLine &&
                      line1 <= text_area.getFirstLine + text_area.getVisibleLines)
                    visible_change = true
                  text_area.invalidateLineRange(line1, line2)
                }
              }
              // FIXME danger of deadlock!?
              if (visible_change) model.buffer.propertiesChanged()

              overview.repaint()  // FIXME really paint here!?
            }
          }

        case bad => System.err.println("command_change_actor: ignoring bad message " + bad)
      }
    }
  }


  /* text_area_extension */

  // simplify slightly odd result of TextArea.getLineEndOffset
  // NB: jEdit already normalizes \r\n and \r to \n
  def visible_line_end(start: Text.Offset, end: Text.Offset): Text.Offset =
  {
    val end1 = end - 1
    if (start <= end1 && end1 < model.buffer.getLength &&
        model.buffer.getSegment(end1, 1).charAt(0) == '\n') end1
    else end
  }

  private val text_area_extension = new TextAreaExtension
  {
    override def paintScreenLineRange(gfx: Graphics2D,
      first_line: Int, last_line: Int, physical_lines: Array[Int],
      start: Array[Int], end: Array[Int], y0: Int, line_height: Int)
    {
      Isabelle.swing_buffer_lock(model.buffer) {
        val snapshot = model.snapshot()
        val saved_color = gfx.getColor
        try {
          var y = y0
          for (i <- 0 until physical_lines.length) {
            if (physical_lines(i) != -1) {
              val line_range = Text.Range(start(i), visible_line_end(start(i), end(i)))
              val cmds = snapshot.node.command_range(snapshot.revert(line_range))
              for ((command, command_start) <- cmds if !command.is_ignored) {
                val range = line_range.restrict(snapshot.convert(command.range + command_start))
                val p = text_area.offsetToXY(range.start)
                val q = text_area.offsetToXY(range.stop)
                gfx.setColor(Document_View.choose_color(snapshot, command))
                gfx.fillRect(p.x, y, q.x - p.x, line_height)
              }
            }
            y += line_height
          }
        }
        finally { gfx.setColor(saved_color) }
      }
    }

    override def getToolTipText(x: Int, y: Int): String =
    {
      Isabelle.swing_buffer_lock(model.buffer) {
        val snapshot = model.snapshot()
        val offset = text_area.xyToOffset(x, y)
        val markup =
          snapshot.select_markup(Text.Range(offset, offset + 1)) {
            case Text.Info(range, XML.Elem(Markup(Markup.ML_TYPING, _), body)) =>
              Isabelle.tooltip(Pretty.string_of(List(Pretty.block(body)), margin = 40))
          } { null }
        if (markup.hasNext) markup.next.info else null
      }
    }
  }


  /* caret handling */

  def selected_command(): Option[Command] =
  {
    Swing_Thread.require()
    model.snapshot().node.proper_command_at(text_area.getCaretPosition)
  }

  private val caret_listener = new CaretListener {
    private val delay = Swing_Thread.delay_last(session.input_delay) {
      session.perspective.event(Session.Perspective)
    }
    override def caretUpdate(e: CaretEvent) { delay() }
  }


  /* overview of command status left of scrollbar */

  private val overview = new JPanel(new BorderLayout)
  {
    private val WIDTH = 10
    private val HEIGHT = 2

    setPreferredSize(new Dimension(WIDTH, 0))

    setRequestFocusEnabled(false)

    addMouseListener(new MouseAdapter {
      override def mousePressed(event: MouseEvent) {
        val line = y_to_line(event.getY)
        if (line >= 0 && line < text_area.getLineCount)
          text_area.setCaretPosition(text_area.getLineStartOffset(line))
      }
    })

    override def addNotify() {
      super.addNotify()
      ToolTipManager.sharedInstance.registerComponent(this)
    }

    override def removeNotify() {
      ToolTipManager.sharedInstance.unregisterComponent(this)
      super.removeNotify
    }

    override def getToolTipText(event: MouseEvent): String =
    {
      val line = y_to_line(event.getY())
      if (line >= 0 && line < text_area.getLineCount) "<html><b>TODO:</b><br>Tooltip</html>"
      else ""
    }

    override def paintComponent(gfx: Graphics)
    {
      super.paintComponent(gfx)
      Swing_Thread.assert()
      val buffer = model.buffer
      Isabelle.buffer_lock(buffer) {
        val snapshot = model.snapshot()
        val saved_color = gfx.getColor  // FIXME needed!?
        try {
          for ((command, start) <- snapshot.node.command_starts if !command.is_ignored) {
            val line1 = buffer.getLineOfOffset(snapshot.convert(start))
            val line2 = buffer.getLineOfOffset(snapshot.convert(start + command.length)) + 1
            val y = line_to_y(line1)
            val height = HEIGHT * (line2 - line1)
            gfx.setColor(Document_View.choose_color(snapshot, command))
            gfx.fillRect(0, y, getWidth - 1, height)
          }
        }
        finally { gfx.setColor(saved_color) }
      }
    }

    private def line_to_y(line: Int): Int =
      (line * getHeight) / (text_area.getBuffer.getLineCount max text_area.getVisibleLines)

    private def y_to_line(y: Int): Int =
      (y * (text_area.getBuffer.getLineCount max text_area.getVisibleLines)) / getHeight
  }


  /* activation */

  private def activate()
  {
    text_area.getPainter.
      addExtension(TextAreaPainter.LINE_BACKGROUND_LAYER + 1, text_area_extension)
    text_area.addCaretListener(caret_listener)
    text_area.addLeftOfScrollBar(overview)
    session.commands_changed += commands_changed_actor
  }

  private def deactivate()
  {
    session.commands_changed -= commands_changed_actor
    text_area.removeLeftOfScrollBar(overview)
    text_area.removeCaretListener(caret_listener)
    text_area.getPainter.removeExtension(text_area_extension)
  }
}