/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH (http://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: http://www.alkacon.com
*
* For further information about OpenCms, please see the
* project website: http://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.ade.containerpage.client.impl;
import org.opencms.gwt.client.util.CmsDomUtil;
import org.opencms.util.CmsStringUtil;
import java.util.ArrayList;
import java.util.List;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.Style;
/**
* A chain of ancestors of a DOM element whose Z-Index can be manipulated.<p>
*
* @since 8.0.0
*/
public final class CmsZIndexChain {
/**
* An entry in a z index ancestor chain.<p>
*/
private static class Entry {
/** The DOM element. */
private Element m_element;
/** If true, the original z-index came from the element itself rather than from the CSS. */
private boolean m_fromElement;
/** The original Z index, either directly from the element, or from CSS rules. */
private Integer m_origZIndex;
/**
* Creates a new entry from an element.<p>
*
* @param element the entry's element
*/
public Entry(Element element) {
m_element = element;
Style style = element.getStyle();
String ownStyle = CmsDomUtil.getZIndex(style);
String computedStyle = CmsDomUtil.getCurrentStyle(element, CmsDomUtil.Style.zIndex);
m_fromElement = !(CmsStringUtil.isEmptyOrWhitespaceOnly(ownStyle));
m_origZIndex = null;
try {
m_origZIndex = Integer.valueOf(computedStyle);
} catch (NumberFormatException e) {
// ignore
}
}
/**
* Bumps the entry's z index to a given value.<p>
*
* @param newZIndex the new value for the z index
*/
public void bump(int newZIndex) {
Style style = m_element.getStyle();
style.clearZIndex();
style.setZIndex(newZIndex);
}
/**
* Returns the original Z index of the element.<p>
*
* @return the original z index
*/
public int getOriginalZIndex() {
if (m_origZIndex == null) {
return 0;
}
return m_origZIndex.intValue();
}
/**
* Resets the entry's z index.<p>
*/
public void reset() {
if ((m_origZIndex == null) || !m_fromElement) {
m_element.getStyle().clearZIndex();
} else {
m_element.getStyle().setZIndex(m_origZIndex.intValue());
}
}
}
/** The list of this chain's entries. */
private List<Entry> m_entries;
/**
* Private constructor to create a Z index chain from a list of entries.<p>
*
* @param entries the list of entries
*/
private CmsZIndexChain(List<Entry> entries) {
m_entries = entries;
}
/**
* Creates a z index chain from an element's ancestors.<p>
*
* @param elem the element whose ancestors should be put in the Z index chain
*
* @return the z index chain for the element's ancestors
*/
public static CmsZIndexChain get(Element elem) {
List<Entry> entries = new ArrayList<Entry>();
do {
Entry entry = new Entry(elem);
entries.add(entry);
elem = elem.getParentElement();
} while (elem != null);
return new CmsZIndexChain(entries);
}
/**
* Bumps all entries of the chain to a given z index value.<p>
*
* @param zIndex a z index value
*/
public void bump(int zIndex) {
for (Entry entry : m_entries) {
entry.bump(zIndex);
}
}
/**
* Returns the maximum z index found in the chain.<p>
*
* @return the maximum z index found in the chain
*/
public int getMaxZIndex() {
int result = 0;
for (Entry entry : m_entries) {
result = Math.max(result, entry.getOriginalZIndex());
}
return result;
}
/**
* Resets the z indices of all entries in the chain.<p>
*/
public void reset() {
for (Entry entry : m_entries) {
entry.reset();
}
}
}