/*  Title:      Tools/jEdit/src/find_dockable.scala

    Author:     Makarius

Dockable window for "find" dialog.

*/

package isabelle.jedit

import isabelle._

import scala.actors.Actor._

import scala.swing.{FlowPanel, Button, Component}

import scala.swing.event.ButtonClicked

import java.awt.BorderLayout

import java.awt.event.{ComponentEvent, ComponentAdapter}

import org.gjt.sp.jedit.View

import org.gjt.sp.jedit.gui.HistoryTextArea

class Find_Dockable(view: View, position: String) extends Dockable(view, position)

{

  Swing_Thread.require()

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

  private val FIND_THEOREMS = "find_theorems"

  private val instance = Document_ID.make().toString

  private var zoom_factor = 100

  private var current_location: Option[Command] = None

  private var current_query: String = ""

  private var current_snapshot = Document.State.init.snapshot()

  private var current_state = Command.empty.init_state

  private var current_output: List[XML.Tree] = Nil

  /* pretty text area */

  val pretty_text_area = new Pretty_Text_Area(view)

  set_content(pretty_text_area)

  private def handle_resize()

  {

    Swing_Thread.require()

    pretty_text_area.resize(Rendering.font_family(),

      (Rendering.font_size("jedit_font_scale") * zoom_factor / 100).round)

  }

  private def handle_update()

  {

    Swing_Thread.require()

    val (new_snapshot, new_state) =

      Document_View(view.getTextArea) match {

        case Some(doc_view) =>

          val snapshot = doc_view.model.snapshot()

          if (!snapshot.is_outdated) {

            current_location match {

              case Some(cmd) =>

                (snapshot, snapshot.state.command_state(snapshot.version, cmd))

              case None =>

                (Document.State.init.snapshot(), Command.empty.init_state)

            }

          }

          else (current_snapshot, current_state)

        case None => (current_snapshot, current_state)

      }

    val new_output =

      (for {

        (_, XML.Elem(Markup(Markup.RESULT, props), body)) <- new_state.results.entries

        if props.contains((Markup.KIND, FIND_THEOREMS))

        if props.contains((Markup.INSTANCE, instance))

      } yield XML.Elem(Markup(Markup.WRITELN_MESSAGE, Nil), body)).toList

    if (new_output != current_output)

      pretty_text_area.update(new_snapshot, new_state.results, Pretty.separate(new_output))

    current_snapshot = new_snapshot

    current_state = new_state

    current_output = new_output

  }

  private def clear_overlay()

  {

    Swing_Thread.require()

    for {

      command <- current_location

      buffer <- JEdit_Lib.jedit_buffer(command.node_name.node)

      model <- PIDE.document_model(buffer)

    } model.remove_overlay(command, FIND_THEOREMS, List(instance, current_query))

    current_location = None

    current_query = ""

  }

  private def apply_query(query: String)

  {

    Swing_Thread.require()

    clear_overlay()

    Document_View(view.getTextArea) match {

      case Some(doc_view) =>

        val snapshot = doc_view.model.snapshot()

        snapshot.node.command_at(doc_view.text_area.getCaretPosition).map(_._1) match {

          case Some(command) =>

            current_location = Some(command)

            current_query = query

            doc_view.model.add_overlay(command, FIND_THEOREMS, List(instance, query))

          case None =>

        }

      case None =>

    }

  }

  private def locate_query()

  {

    Swing_Thread.require()

    current_location match {

      case Some(command) =>

        val snapshot = PIDE.session.snapshot(command.node_name)

        val commands = snapshot.node.commands

        if (commands.contains(command)) {

          val sources = commands.iterator.takeWhile(_ != command).map(_.source)

          val (line, column) = ((1, 1) /: sources)(Symbol.advance_line_column)

          Hyperlink(command.node_name.node, line, column).follow(view)

        }

      case None =>

    }

  }

  /* main actor */

  private val main_actor = actor {

    loop {

      react {

        case _: Session.Global_Options =>

          Swing_Thread.later { handle_resize() }

        case changed: Session.Commands_Changed =>

          current_location match {

            case Some(command) if changed.commands.contains(command) =>

              Swing_Thread.later { handle_update() }

            case _ =>

          }

        case bad =>

          java.lang.System.err.println("Find_Dockable: ignoring bad message " + bad)

      }

    }

  }

  override def init()

  {

    Swing_Thread.require()

    PIDE.session.global_options += main_actor

    PIDE.session.commands_changed += main_actor

    handle_resize()

  }

  override def exit()

  {

    Swing_Thread.require()

    PIDE.session.global_options -= main_actor

    PIDE.session.commands_changed -= main_actor

    delay_resize.revoke()

  }

  /* resize */

  private val delay_resize =

    Swing_Thread.delay_first(PIDE.options.seconds("editor_update_delay")) { handle_resize() }

  addComponentListener(new ComponentAdapter {

    override def componentResized(e: ComponentEvent) { delay_resize.invoke() }

  })

  /* controls */

  private val query = new HistoryTextArea("isabelle-find-theorems") {

    { val max = getPreferredSize; max.width = Integer.MAX_VALUE; setMaximumSize(max) }

    setColumns(25)

    setRows(1)

  }

  private val query_wrapped = Component.wrap(query)

  private val find = new Button("Find") {

    tooltip = "Find theorems meeting specified criteria"

    reactions += { case ButtonClicked(_) => apply_query(query.getText) }

  }

  private val locate = new Button("Locate") {

    tooltip = "Locate context of current query within source text"

    reactions += { case ButtonClicked(_) => locate_query() }

  }

  private val zoom = new GUI.Zoom_Box(factor => { zoom_factor = factor; handle_resize() }) {

    tooltip = "Zoom factor for output font size"

  }

  private val controls =

    new FlowPanel(FlowPanel.Alignment.Right)(query_wrapped, find, locate, zoom)

  add(controls.peer, BorderLayout.NORTH)

}