/*
 * Ext GWT 2.2.4 - Ext for GWT
 * Copyright(c) 2007-2010, Ext JS, LLC.
 * licensing@extjs.com
 * 
 * http://extjs.com/license
 */
package com.extjs.gxt.ui.client.widget;

import java.util.Stack;

import com.extjs.gxt.ui.client.core.XDOM;
import com.extjs.gxt.ui.client.event.FxEvent;
import com.extjs.gxt.ui.client.event.Listener;
import com.extjs.gxt.ui.client.event.PreviewEvent;
import com.extjs.gxt.ui.client.fx.FxConfig;
import com.extjs.gxt.ui.client.util.BaseEventPreview;
import com.google.gwt.user.client.DOM;
import com.google.gwt.user.client.Element;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.ui.RootPanel;

/**
 * A panel that grays out the view port and displays a widget above it.
 * 
 * <dl>
 * <dt>Inherited Events:</dt>
 * <dd>BoxComponent Move</dd>
 * <dd>BoxComponent Resize</dd>
 * <dd>Component Enable</dd>
 * <dd>Component Disable</dd>
 * <dd>Component BeforeHide</dd>
 * <dd>Component Hide</dd>
 * <dd>Component BeforeShow</dd>
 * <dd>Component Show</dd>
 * <dd>Component Attach</dd>
 * <dd>Component Detach</dd>
 * <dd>Component BeforeRender</dd>
 * <dd>Component Render</dd>
 * <dd>Component BrowserEvent</dd>
 * <dd>Component BeforeStateRestore</dd>
 * <dd>Component StateRestore</dd>
 * <dd>Component BeforeStateSave</dd>
 * <dd>Component SaveState</dd>
 * </dl>
 */
public class ModalPanel extends BoxComponent {

  private static Stack<ModalPanel> modalStack = new Stack<ModalPanel>();

  /**
   * Returns a ModalPanel from the stack.
   * 
   * @return the panel
   */
  public static ModalPanel pop() {
    ModalPanel panel = modalStack.size() > 0 ? modalStack.pop() : null;
    if (panel == null) {
      panel = new ModalPanel();
    }
    return panel;
  }

  /**
   * Pushes a panel back onto the stack.
   * 
   * @param panel the panel
   */
  public static void push(ModalPanel panel) {
    if (panel != null) {
      panel.hide();
      modalStack.push(panel);
    }
  }

  private boolean blink;
  private Component component;
  private boolean blinking;
  private BaseEventPreview eventPreview;

  /**
   * Creates a new model panel.
   */
  public ModalPanel() {
    baseStyle = "x-modal";
    shim = true;
    setShadow(false);
    monitorWindowResize = true;
  }

  /**
   * Returns the panel's event preview.
   * 
   * @return the event preview
   */
  public BaseEventPreview getEventPreview() {
    return eventPreview;
  }

  /**
   * Hides the panel.
   */
  public void hide() {
    super.hide();
    setZIndex(-1);
    component = null;
    if (eventPreview != null) {
      eventPreview.getIgnoreList().removeAll();
      eventPreview.remove();
    }
    RootPanel.get().remove(this);
  }

  /**
   * Returns true if blinking is enabled.
   * 
   * @return the blink state
   */
  public boolean isBlink() {
    return blink;
  }

  /**
   * True to blink the widget being displayed when the use clicks outside of the
   * widgets bounds (defaults to false).
   * 
   * @param blink true to blink
   */
  public void setBlink(boolean blink) {
    this.blink = blink;
  }

  /**
   * Displays the panel.
   */
  public void show(Component component) {
    this.component = component;
    RootPanel.get().add(this);

    el().makePositionable(true);
    el().updateZIndex(0);
    component.el().updateZIndex(0);

    super.show();

    eventPreview.getIgnoreList().removeAll();
    eventPreview.getIgnoreList().add(component.getElement());
    eventPreview.add();

    syncModal();
  }

  /**
   * Syncs to the viewport.
   */
  public void syncModal() {
    setSize(0, 0);
    int w = XDOM.getViewWidth(true);
    int h = XDOM.getViewHeight(true);
    setSize(w, h);
  }

  @Override
  protected void doAttachChildren() {
    super.doAttachChildren();
    ComponentHelper.doAttach(component);
  }

  @Override
  protected void doDetachChildren() {
    super.doDetachChildren();
    ComponentHelper.doDetach(component);
  }

  @Override
  protected void onDetach() {
    super.onDetach();
    if (eventPreview != null) {
      eventPreview.remove();
    }
  }

  @Override
  protected void onRender(Element target, int index) {
    setElement(DOM.createDiv(), target, index);
    super.onRender(target, index);
    eventPreview = new BaseEventPreview() {
      @Override
      protected boolean onPreview(PreviewEvent pe) {
        if (pe.getEventTypeInt() == Event.ONMOUSEDOWN && getElement().isOrHasChild(pe.getTarget())
            && (fly(pe.getTarget()).findParent(".x-ignore", -1) == null)) {
          if (blink && !blinking) {
            blinking = true;
            component.el().blink(new FxConfig(new Listener<FxEvent>() {
              public void handleEvent(FxEvent fe) {
                blinking = false;
                component.focus();
              }
            }));
          } else if (!blink) {
            component.focus();
          }

        }
        return super.onPreview(pe);
      }

    };
    eventPreview.setAutoHide(false);
  }

  @Override
  protected void onWindowResize(int width, int height) {
    super.onWindowResize(width, height);
    syncModal();
  }

}