package org.kuali.student.common.ui.client.widgets.panels.collapsable;

 import org.kuali.student.common.ui.client.widgets.KSButton;

 import com.google.gwt.animation.client.Animation;

 import com.google.gwt.core.client.GWT;

 import com.google.gwt.event.dom.client.ClickEvent;

 import com.google.gwt.event.dom.client.ClickHandler;

 import com.google.gwt.uibinder.client.UiBinder;

 import com.google.gwt.uibinder.client.UiField;

 import com.google.gwt.user.client.DOM;

 import com.google.gwt.user.client.ui.Composite;

 import com.google.gwt.user.client.ui.DisclosurePanel;

 import com.google.gwt.user.client.ui.HTMLPanel;

 import com.google.gwt.user.client.ui.SimplePanel;

 import com.google.gwt.user.client.ui.Widget;

 public class VerticalCollapsableDrawer extends Composite{

                 private static VerticalCollapsableDrawerBinder uiBinder = GWT

                 .create(VerticalCollapsableDrawerBinder.class);

                 interface VerticalCollapsableDrawerBinder extends

                         UiBinder<Widget, VerticalCollapsableDrawer> {

                 }

                 @UiField

                 SimplePanel content;

                 @UiField

                 KSButton drawerHandle;

                 @UiField

                 HTMLPanel container;

                 private boolean isOpen = true;

                 private ContentAnimation animation = new ContentAnimation();

                 public VerticalCollapsableDrawer(){

                         initWidget(uiBinder.createAndBindUi(this));

                         drawerHandle.setText("\u00AB");

                         drawerHandle.addClickHandler(new ClickHandler(){

                                 @Override

                                 public void onClick(ClickEvent event) {

                                         if(isOpen){

                                                 close();

                                                 drawerHandle.setText("\u00BB");

                                         }

                                         else{

                                                 open();

                                                 drawerHandle.setText("\u00AB");

                                         }

                                 }

                         });

                 }

                 @Override

                 protected void onLoad() {

                         super.onLoad();

                         container.getElementById("collapsePanel").setAttribute("style", "height: " 

                                         + content.getOffsetHeight() + "px");

                         //this.getElement().g;

                 }

                 public void open(){

                         isOpen = true;

                         animation.setOpen(this, true);

                 }

                 public void close(){

                         isOpen = false;

                         animation.setOpen(this, true);

                 }

                 public void setContent(Widget w){

                         content.setWidget(w);

                 }

                 private static class ContentAnimation extends Animation {

                             /**

                              * Whether the item is being opened or closed.

                              */

                             private boolean opening;

                             /**

                              * The {@link DisclosurePanel} being affected.

                              */

                             private VerticalCollapsableDrawer curPanel;

                             /**

                              * Open or close the content.

                              *

                              * @param panel the panel to open or close

                              * @param animate true to animate, false to open instantly

                              */

                             public void setOpen(VerticalCollapsableDrawer panel, boolean animate) {

                               // Immediately complete previous open

                               cancel();

                               // Open the new item

                               if (animate) {

                                 curPanel = panel;

                                 opening = panel.isOpen;

                                 run(1000);

                               } else {

                                 panel.content.setVisible(panel.isOpen);

                                 if (panel.isOpen) {

                                   // Special treatment on the visible case to ensure LazyPanel works

                                   panel.content.setVisible(true);

                                 }

                               }

                             }

                             @Override

                             protected void onComplete() {

                               if (!opening) {

                                 curPanel.content.setVisible(false);

                               }

                               DOM.setStyleAttribute(curPanel.content.getElement(), "width",

                                   "auto");

                               DOM.setStyleAttribute(curPanel.content.getElement(), "overflow", "visible");

                               curPanel = null;

                             }

                             @Override

                             protected void onStart() {

                               super.onStart();

                               DOM.setStyleAttribute(curPanel.content.getElement(), "overflow", "hidden");

                               if (opening) {

                                 curPanel.content.setVisible(true);

                                 // Special treatment on the visible case to ensure LazyPanel works

                                 curPanel.content.setVisible(true);

                              }

                             }

                             @Override

                             protected void onUpdate(double progress) {

                               int scrollWidth = DOM.getElementPropertyInt(

                                   curPanel.content.getElement(), "scrollWidth");

                               int width = (int) (progress * scrollWidth);

                               if (!opening) {

                                 width = scrollWidth - width;

                               }

                               width = Math.max(width, 1);

                               DOM.setStyleAttribute(curPanel.content.getElement(), "width",

                                   width + "px");

                               DOM.setStyleAttribute(curPanel.content.getElement(), "height",

                                   "auto");

                             }

                  }

 }