/*  Title:      Pure/GUI/gui.scala

     Module:     PIDE-GUI

     Author:     Makarius

 Basic GUI tools (for AWT/Swing).

 */

 package isabelle

 import java.lang.{ClassLoader, ClassNotFoundException, NoSuchMethodException}

 import java.awt.{Image, Component, Container, Toolkit, Window, Font, KeyboardFocusManager}

 import java.awt.font.{TextAttribute, TransformAttribute, FontRenderContext, LineMetrics}

 import java.awt.geom.AffineTransform

 import javax.swing.{ImageIcon, JOptionPane, UIManager, JLayeredPane, JFrame, JWindow,

   JButton, JTextField}

 import scala.collection.convert.WrapAsJava

 import scala.swing.{ComboBox, TextArea, ScrollPane}

 import scala.swing.event.SelectionChanged

 object GUI

 {

   /* Swing look-and-feel */

   def get_laf(): String =

   {

     if (Platform.is_windows || Platform.is_macos)

       UIManager.getSystemLookAndFeelClassName()

     else

       UIManager.getInstalledLookAndFeels().find(_.getName == "Nimbus").map(_.getClassName)

         .getOrElse(UIManager.getCrossPlatformLookAndFeelClassName())

   }

   def init_laf(): Unit = UIManager.setLookAndFeel(get_laf())

   def is_macos_laf(): Boolean =

     Platform.is_macos &&

     UIManager.getSystemLookAndFeelClassName() == UIManager.getLookAndFeel.getClass.getName

   /* plain focus traversal, notably for text fields */

   def plain_focus_traversal(component: Component)

   {

     val dummy_button = new JButton

     def apply(id: Int): Unit =

       component.setFocusTraversalKeys(id, dummy_button.getFocusTraversalKeys(id))

     apply(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS)

     apply(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS)

   }

   /* X11 window manager */

   def window_manager(): Option[String] =

   {

     if (Platform.is_windows || Platform.is_macos) None

     else

       try {

         val XWM = Class.forName("sun.awt.X11.XWM", true, ClassLoader.getSystemClassLoader)

         val getWM = XWM.getDeclaredMethod("getWM")

         getWM.setAccessible(true)

         getWM.invoke(null) match {

           case null => None

           case wm => Some(wm.toString)

         }

       }

       catch {

         case _: ClassNotFoundException => None

         case _: NoSuchMethodException => None

       }

   }

   /* simple dialogs */

   def scrollable_text(txt: String, width: Int = 60, height: Int = 20, editable: Boolean = false)

     : ScrollPane =

   {

     val text = new TextArea(txt)

     if (width > 0) text.columns = width

     if (height > 0 && split_lines(txt).length > height) text.rows = height

     text.editable = editable

     new ScrollPane(text)

   }

   private def simple_dialog(kind: Int, default_title: String,

     parent: Component, title: String, message: Seq[Any])

   {

     Swing_Thread.now {

       val java_message = message map { case x: scala.swing.Component => x.peer case x => x }

       JOptionPane.showMessageDialog(parent,

         java_message.toArray.asInstanceOf[Array[AnyRef]],

         if (title == null) default_title else title, kind)

     }

   }

   def dialog(parent: Component, title: String, message: Any*) =

     simple_dialog(JOptionPane.PLAIN_MESSAGE, null, parent, title, message)

   def warning_dialog(parent: Component, title: String, message: Any*) =

     simple_dialog(JOptionPane.WARNING_MESSAGE, "Warning", parent, title, message)

   def error_dialog(parent: Component, title: String, message: Any*) =

     simple_dialog(JOptionPane.ERROR_MESSAGE, "Error", parent, title, message)

   def confirm_dialog(parent: Component, title: String, option_type: Int, message: Any*): Int =

     Swing_Thread.now {

       val java_message = message map { case x: scala.swing.Component => x.peer case x => x }

       JOptionPane.showConfirmDialog(parent,

         java_message.toArray.asInstanceOf[Array[AnyRef]], title,

           option_type, JOptionPane.QUESTION_MESSAGE)

     }

   /* zoom box */

   class Zoom_Box(apply_factor: Int => Unit) extends ComboBox[String](

     List("50%", "70%", "85%", "100%", "125%", "150%", "175%", "200%", "300%", "400%"))

   {

     val Factor = "([0-9]+)%?".r

     def parse(text: String): Int =

       text match {

         case Factor(s) =>

           val i = Integer.parseInt(s)

           if (10 <= i && i < 1000) i else 100

         case _ => 100

       }

     def print(i: Int): String = i.toString + "%"

     def set_item(i: Int) {

       peer.getEditor match {

         case null =>

         case editor => editor.setItem(print(i))

       }

     }

     makeEditable()(c => new ComboBox.BuiltInEditor(c)(text => print(parse(text)), x => x))

     peer.getEditor.getEditorComponent match {

       case text: JTextField => text.setColumns(4)

       case _ =>

     }

     reactions += {

       case SelectionChanged(_) => apply_factor(parse(selection.item))

     }

     listenTo(selection)

     selection.index = 3

   }

   /* tooltip with multi-line support */

   def tooltip_lines(text: String): String =

     if (text == null || text == "") null

     else "<html>" + HTML.encode(text) + "</html>"

   /* screen resolution */

   def resolution_scale(): Double = Toolkit.getDefaultToolkit.getScreenResolution.toDouble / 72

   def resolution_scale(i: Int): Int = (i.toDouble * resolution_scale()).round.toInt

   /* icon */

   def isabelle_icon(): ImageIcon =

     new ImageIcon(getClass.getClassLoader.getResource("isabelle/isabelle_transparent-32.gif"))

   def isabelle_icons(): List[ImageIcon] =

     for (icon <- List("isabelle/isabelle_transparent-32.gif", "isabelle/isabelle_transparent.gif"))

       yield new ImageIcon(getClass.getClassLoader.getResource(icon))

   def isabelle_image(): Image = isabelle_icon().getImage

   def isabelle_images(): java.util.List[Image] =

     WrapAsJava.seqAsJavaList(isabelle_icons.map(_.getImage))

   /* component hierachy */

   def get_parent(component: Component): Option[Container] =

     component.getParent match {

       case null => None

       case parent => Some(parent)

     }

   def ancestors(component: Component): Iterator[Container] = new Iterator[Container] {

     private var next_elem = get_parent(component)

     def hasNext(): Boolean = next_elem.isDefined

     def next(): Container =

       next_elem match {

         case Some(parent) =>

           next_elem = get_parent(parent)

           parent

         case None => Iterator.empty.next()

       }

   }

   def parent_window(component: Component): Option[Window] =

     ancestors(component).collectFirst({ case x: Window => x })

   def layered_pane(component: Component): Option[JLayeredPane] =

     parent_window(component) match {

       case Some(window: JWindow) => Some(window.getLayeredPane)

       case Some(frame: JFrame) => Some(frame.getLayeredPane)

       case _ => None

     }

   /* font operations */

   def font_metrics(font: Font): LineMetrics =

     font.getLineMetrics("", new FontRenderContext(null, false, false))

   def imitate_font(family: String, font: Font, scale: Double = 1.0): Font =

   {

     val font1 = new Font(family, font.getStyle, font.getSize)

     val size = scale * (font_metrics(font).getAscent / font_metrics(font1).getAscent * font.getSize)

     font1.deriveFont(size.round.toInt)

   }

   def transform_font(font: Font, transform: AffineTransform): Font =

   {

     import scala.collection.JavaConversions._

     font.deriveFont(Map(TextAttribute.TRANSFORM -> new TransformAttribute(transform)))

   }

 }