src/Pure/System/system_dialog.scala

clarified result;

/*  Title:      Pure/Tools/system_dialog.scala
    Author:     Makarius

Dialog for system processes, with optional output window.
*/

package isabelle


import java.awt.{GraphicsEnvironment, Point, Font}

import scala.swing.{ScrollPane, Button, CheckBox, FlowPanel,
  BorderPanel, Frame, TextArea, SwingApplication, Component, Label}
import scala.swing.event.ButtonClicked


class System_Dialog extends Build.Progress
{
  val result = Future.promise[Int]


  /* GUI state -- owned by Swing thread */

  private var _title = "Isabelle"
  private var _window: Option[Window] = None
  private var _return_code: Option[Int] = None

  private def check_window(): Window =
  {
    Swing_Thread.require()

    _window match {
      case Some(window) => window
      case None =>
        val window = new Window
        _window = Some(window)

        window.pack()
        val point = GraphicsEnvironment.getLocalGraphicsEnvironment().getCenterPoint()
        window.location =
          new Point(point.x - window.size.width / 2, point.y - window.size.height / 2)
        window.visible = true

        window
      }
  }

  private def conclude()
  {
    Swing_Thread.require()
    require(_return_code.isDefined)
    require(!result.is_finished)

    _window match {
      case None =>
      case Some(window) =>
        window.visible = false
        _window = None
    }

    result.fulfill(_return_code.get)
  }


  /* window */

  private class Window extends Frame
  {
    title = _title
    iconImage = GUI.isabelle_image()

    override def closeOperation { if (_return_code.isDefined) conclude() }


    /* text */

    val text = new TextArea {
      font = new Font("SansSerif", Font.PLAIN, GUI.resolution_scale(10) max 14)
      editable = false
      columns = 50
      rows = 20
    }

    val scroll_text = new ScrollPane(text)


    /* layout panel with dynamic actions */

    val action_panel = new FlowPanel(FlowPanel.Alignment.Center)()
    val layout_panel = new BorderPanel
    layout_panel.layout(scroll_text) = BorderPanel.Position.Center
    layout_panel.layout(action_panel) = BorderPanel.Position.South

    contents = layout_panel

    def set_actions(cs: Component*)
    {
      action_panel.contents.clear
      action_panel.contents ++= cs
      layout_panel.revalidate
      layout_panel.repaint
    }


    /* actions */

    var do_auto_close = true
    def can_auto_close: Boolean = do_auto_close && _return_code == Some(0)

    val auto_close = new CheckBox("Auto close") {
      reactions += {
        case ButtonClicked(_) => do_auto_close = this.selected
        if (can_auto_close) conclude()
      }
    }
    auto_close.selected = do_auto_close
    auto_close.tooltip = "Automatically close dialog when finished"


    val stop_button = new Button("Stop") {
      reactions += {
        case ButtonClicked(_) =>
          is_stopped = true
          set_actions(new Label("Stopping ..."))
      }
    }

    set_actions(stop_button, auto_close)


    /* exit */

    val delay_exit =
      Swing_Thread.delay_first(Time.seconds(1.0))
      {
        if (can_auto_close) conclude()
        else {
          val button =
            new Button(if (_return_code == Some(0)) "OK" else "Exit") {
              reactions += { case ButtonClicked(_) => conclude() }
            }
          set_actions(button)
          button.peer.getRootPane.setDefaultButton(button.peer)
        }
      }
  }


  /* progress operations */

  def title(txt: String): Unit =
    Swing_Thread.later {
      _title = txt
      _window.foreach(window => window.title = txt)
    }

  def return_code(rc: Int): Unit =
    Swing_Thread.later {
      _return_code = Some(rc)
      _window.foreach(window => window.delay_exit.invoke)
    }

  override def echo(txt: String): Unit =
    Swing_Thread.later {
      val window = check_window()
      window.text.append(txt + "\n")
      val vertical = window.scroll_text.peer.getVerticalScrollBar
      vertical.setValue(vertical.getMaximum)
    }

  override def theory(session: String, theory: String): Unit =
    echo(session + ": theory " + theory)

  @volatile private var is_stopped = false
  override def stopped: Boolean = is_stopped
}