content: /*
   * This library is part of OpenCms -
   * the Open Source Content Management System
   *
   * Copyright (c) Alkacon Software GmbH & Co. KG (https://www.alkacon.com)
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * Lesser General Public License for more details.
   *
   * For further information about Alkacon Software, please see the
   * company website: https://www.alkacon.com
   *
   * For further information about OpenCms, please see the
   * project website: https://www.opencms.org
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  package org.opencms.gwt.client.ui.tree;
  
  import org.opencms.gwt.client.dnd.CmsDNDHandler.Orientation;
  import org.opencms.gwt.client.ui.CmsList;
  import org.opencms.gwt.client.util.CmsDebugLog;
  import org.opencms.gwt.client.util.CmsDomUtil;
  
  import com.google.gwt.dom.client.Element;
  import com.google.gwt.event.logical.shared.CloseEvent;
  import com.google.gwt.event.logical.shared.CloseHandler;
  import com.google.gwt.event.logical.shared.HasCloseHandlers;
  import com.google.gwt.event.logical.shared.HasOpenHandlers;
  import com.google.gwt.event.logical.shared.OpenEvent;
  import com.google.gwt.event.logical.shared.OpenHandler;
  import com.google.gwt.event.shared.GwtEvent;
  import com.google.gwt.event.shared.HandlerRegistration;
  import com.google.gwt.event.shared.SimpleEventBus;
  import com.google.gwt.user.client.Timer;
  import com.google.gwt.user.client.ui.HasAnimation;
  
  /**
   * A tree of list items.<p>
   *
   * @param <I> the specific tree item implementation
   *
   * @since 8.0.0
   */
  public class CmsTree<I extends CmsTreeItem> extends CmsList<I>
  implements HasOpenHandlers<I>, HasCloseHandlers<I>, HasAnimation {
  
      /**
       * Timer to set sub item list visible.<p>
       */
      private class OpenTimer extends Timer {
  
          /** The tree item. */
          private CmsTreeItem m_item;
  
          /**
           * Constructor.<p>
           *
           * @param item the tree item
           */
          protected OpenTimer(CmsTreeItem item) {
  
              m_item = item;
          }
  
          /**
           * @see com.google.gwt.user.client.Timer#run()
           */
          @Override
          public void run() {
  
              m_item.setOpen(true);
              removeOpenTimer();
          }
  
          /**
           * Checks if the timer is running for the given tree item.<p>
           *
           * @param item the tree item to check
           * @return <code>true</code> if the given item matches the timer item
           */
          protected boolean checkTimer(CmsTreeItem item) {
  
              return item == m_item;
          }
  
      }
  
      /** The event bus for the tree. */
      protected SimpleEventBus m_eventBus;
  
      /** Flag to indicate is animations are enabled or not. */
      private boolean m_animate;
  
      /** The open timer if one is running. */
      private OpenTimer m_openTimer;
  
      /** The parent path of the current placeholder. */
      private String m_placeholderPath;
  
      /** Flag to indicate if dropping on root level is enabled or not. */
      private boolean m_rootDropEnabled;
  
      /**
       * Constructor.<p>
       */
      public CmsTree() {
  
          m_animate = false;
          m_eventBus = new SimpleEventBus();
      }
  
      /**
       * @see com.google.gwt.event.logical.shared.HasCloseHandlers#addCloseHandler(com.google.gwt.event.logical.shared.CloseHandler)
       */
      public HandlerRegistration addCloseHandler(CloseHandler<I> handler) {
  
          return m_eventBus.addHandlerToSource(CloseEvent.getType(), this, handler);
      }
  
      /**
       * @see com.google.gwt.event.logical.shared.HasOpenHandlers#addOpenHandler(com.google.gwt.event.logical.shared.OpenHandler)
       */
      public HandlerRegistration addOpenHandler(final OpenHandler<I> handler) {
  
          return m_eventBus.addHandlerToSource(OpenEvent.getType(), this, handler);
      }
  
      /**
       * Cancels the open timer if present.<p>
       */
      public void cancelOpenTimer() {
  
          if (m_openTimer != null) {
              m_openTimer.cancel();
              m_openTimer = null;
          }
      }
  
      /**
       * Closes all empty entries.<p>
       */
      public void closeAllEmpty() {
  
          CmsDebugLog.getInstance().printLine("closing all empty");
          int childCount = getWidgetCount();
          for (int index = 0; index < childCount; index++) {
              CmsTreeItem item = getItem(index);
              if (item.isOpen()) {
                  item.closeAllEmptyChildren();
              }
          }
      }
  
      /**
       * Fires the close event for an item.<p>
       *
       * @param item the item for which to fire the close event
       */
      public void fireClose(I item) {
  
          CloseEvent.fire(this, item);
      }
  
      /**
       * @see com.google.gwt.user.client.ui.Widget#fireEvent(com.google.gwt.event.shared.GwtEvent)
       */
      @Override
      public void fireEvent(GwtEvent<?> event) {
  
          m_eventBus.fireEventFromSource(event, this);
      }
  
      /**
       * Fires an open event for a tree item.<p>
       *
       * @param item the tree item for which the open event should be fired
       */
      public void fireOpen(I item) {
  
          OpenEvent.fire(this, item);
      }
  
      /**
       * Returns the placeholder path.<p>
       *
       * @return the path
       */
      public String getPlaceholderPath() {
  
          return m_placeholderPath;
      }
  
      /**
       * @see com.google.gwt.user.client.ui.HasAnimation#isAnimationEnabled()
       */
      public boolean isAnimationEnabled() {
  
          return m_animate;
      }
  
      /**
       * Returns if dropping on root level is enabled or not.<p>
       *
       * @return <code>true</code> if dropping on root level is enabled
       */
      public boolean isRootDropEnabled() {
  
          return m_rootDropEnabled;
      }
  
      /**
       * @see org.opencms.gwt.client.ui.CmsList#removePlaceholder()
       */
      @Override
      public void removePlaceholder() {
  
          super.removePlaceholder();
          m_placeholderPath = null;
      }
  
      /**
       * @see org.opencms.gwt.client.ui.CmsList#repositionPlaceholder(int, int, Orientation)
       */
      @Override
      public void repositionPlaceholder(int x, int y, Orientation orientation) {
  
          int widgetCount = getWidgetCount();
          for (int index = 0; index < widgetCount; index++) {
              CmsTreeItem item = getItem(index);
              Element itemElement = item.getElement();
              boolean over = false;
              switch (orientation) {
                  case HORIZONTAL:
                      over = CmsDomUtil.checkPositionInside(itemElement, x, -1);
                      break;
                  case VERTICAL:
                      over = CmsDomUtil.checkPositionInside(itemElement, -1, y);
                      break;
                  case ALL:
                  default:
                      over = CmsDomUtil.checkPositionInside(itemElement, x, y);
              }
  
              if (over) {
                  m_placeholderIndex = item.repositionPlaceholder(x, y, m_placeholder, orientation);
                  return;
              }
              if (isDNDTakeAll() && (index == (widgetCount - 1))) {
                  // last item of the list, no matching item was found and take-all is enabled
                  // check if cursor position is above or below
                  int relativeTop = CmsDomUtil.getRelativeY(y, getElement());
                  int elementHeight = getElement().getOffsetHeight();
                  if (relativeTop <= 0) {
                      if (isRootDropEnabled()) {
                          getElement().insertBefore(m_placeholder, getItem(0).getElement());
                          setPlaceholderPath("/");
                          m_placeholderIndex = 0;
                      }
                  } else {
                      if (relativeTop > elementHeight) {
                          // insert as last into last opened tree-item
                          if (item.isOpen() && (item.getChildCount() > 0)) {
                              int originalPathLevel = -1;
                              if ((getDnDHandler() != null) && (getDnDHandler().getDraggable() instanceof CmsTreeItem)) {
                                  originalPathLevel = CmsTreeItem.getPathLevel(
                                      ((CmsTreeItem)getDnDHandler().getDraggable()).getPath()) - 1;
                              }
                              // insert into the tree as last visible item
                              CmsTreeItem lastOpened = CmsTreeItem.getLastOpenedItem(item, originalPathLevel, true);
                              m_placeholderIndex = lastOpened.insertPlaceholderAsLastChild(m_placeholder);
                          } else if (isRootDropEnabled()) {
                              getElement().insertAfter(m_placeholder, itemElement);
                              setPlaceholderPath("/");
                              m_placeholderIndex = widgetCount;
                          }
                      }
                  }
              }
          }
      }
  
      /**
       * @see com.google.gwt.user.client.ui.HasAnimation#setAnimationEnabled(boolean)
       */
      public void setAnimationEnabled(boolean enable) {
  
          m_animate = enable;
      }
  
      /**
       * Here the meaning is enabling dropping on the root level.<p>
       *
       * Use {@link CmsTreeItem#setDropEnabled(boolean)} for dropping on tree items.<p>
       *
       * @see org.opencms.gwt.client.ui.CmsList#setDropEnabled(boolean)
       */
      @Override
      public void setDropEnabled(boolean enabled) {
  
          super.setDropEnabled(enabled);
      }
  
      /**
       * Sets a timer to set a tree item open.<p>
       *
       * @param item the item to open
       */
      public void setOpenTimer(CmsTreeItem item) {
  
          if (item.isOpen()) {
              return;
          }
          if (m_openTimer != null) {
              if (m_openTimer.checkTimer(item)) {
                  return;
              }
              m_openTimer.cancel();
          }
          m_openTimer = new OpenTimer(item);
          m_openTimer.schedule(100);
      }
  
      /**
       * Sets the drop on root enabled.<p>
       *
       * @param rootDropEnabled <code>true</code> to enable dropping on root level
       */
      public void setRootDropEnabled(boolean rootDropEnabled) {
  
          m_rootDropEnabled = rootDropEnabled;
      }
  
      /**
       * @see org.opencms.gwt.client.ui.CmsList#registerItem(org.opencms.gwt.client.ui.I_CmsListItem)
       */
      @Override
      @SuppressWarnings("unchecked")
      protected void registerItem(I item) {
  
          super.registerItem(item);
          item.setTree((CmsTree<CmsTreeItem>)this);
      }
  
      /**
       * Sets the timer reference to <code>null</code>.<p>
       */
      protected void removeOpenTimer() {
  
          m_openTimer = null;
      }
  
      /**
       * @see org.opencms.gwt.client.ui.CmsList#setPlaceholder(com.google.gwt.dom.client.Element)
       */
      @Override
      protected void setPlaceholder(Element placeholder) {
  
          super.setPlaceholder(placeholder);
      }
  
      /**
       * Sets the placeholder path.<p>
       *
       * @param path the path
       */
      protected void setPlaceholderPath(String path) {
  
          m_placeholderPath = path;
      }
  }
  