/*******************************************************************************
 * Copyright (c) 2006 Sybase, Inc. and others.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Sybase, Inc. - initial API and implementation
 *******************************************************************************/
package org.eclipse.jst.pagedesigner.converter;

import java.util.Set;

import org.eclipse.jst.pagedesigner.IHTMLConstants;
import org.eclipse.jst.pagedesigner.PDPlugin;
import org.eclipse.jst.pagedesigner.dtmanager.DTManager;
import org.eclipse.wst.xml.core.internal.provisional.document.IDOMDocument;
import org.eclipse.wst.xml.core.internal.provisional.document.IDOMText;
import org.w3c.dom.Attr;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * @author mengbo
 * @version 1.5
 */
public class ConverterUtil {
	/**
	 * 
	 * @param source
	 * @param dest
	 * @param ignore
	 */
	public static void copyAllAttributes(Element source, Element dest,
			Set ignore) {
		NamedNodeMap attrs = source.getAttributes();
		for (int i = 0, size = attrs.getLength(); i < size; i++) {
			Attr attr = (Attr) attrs.item(i);
			if (ignore == null || !ignore.contains(attr.getName())) {
				dest.setAttribute(attr.getName(), attr.getValue());
			}
		}
	}

	/**
	 * copy a single attribute (if exist)
	 * 
	 * @param source
	 * @param srcattr
	 * @param dest
	 * @param destattr
	 */
	public static void copyAttribute(Element source, String srcattr,
			Element dest, String destattr) {
		Attr attr = source.getAttributeNode(srcattr);
		if (attr != null) {
			dest.setAttribute(destattr, attr.getValue());
		}
	}

	/**
	 * @param hostElement
	 * @return true if hostElement represents an empty container
	 */
	public static boolean isEmptyContainer(Element hostElement) {
		NodeList nl = hostElement.getChildNodes();
		if (nl == null || nl.getLength() == 0) {
			return true;
		}

		for (int i = 0, n = nl.getLength(); i < n; i++) {
			Node node = nl.item(i);
			if (!(node instanceof IDOMText)) {
				return false;
			}
			if (!((IDOMText) node).isElementContentWhitespace()) {
				return false;
			}
		}
		return true;
	}

	/**
	 * @param document
	 * @param text
	 * @return the description element in the document containing text
	 */
	public static Element createDescriptionElement(IDOMDocument document,
			String text) {
		if (document == null) {
			return null;
		}
		Element span = document.createElement(IHTMLConstants.TAG_SPAN);
		span.setAttribute(
				"style", "color:gray;font-style:italic;font-size:normal;"); //$NON-NLS-1$ //$NON-NLS-2$
		if (text == null) {
			span.appendChild(document.createTextNode(PDPlugin
					.getResourceString("ConverterUtil.Description"))); //$NON-NLS-1$
		} else {
			span.appendChild(document.createTextNode(text));
		}
		return span;
	}

	/**
	 * Method to find the resulting converted tag containing a given
	 * source element. The converted element that will be
	 * the parent tag is returned so the caller can then determine
	 * if the parent is part of a table, header, body, footer, row,
	 * cell, or some other element. 
	 * 
	 * @param srcElem the source element to test.
	 * @param childElem a child of the source element (used by a
	 *                  recursive call to handle special case where
	 *                  it was moved up a level to the child model
	 *                  list of the grandparent).
	 * @return a converted element of the type that will contain the
	 *         source element. 
	 */
	static Node findConvertedParentElement(Element srcElem, Element childElem) {
		Node parent = srcElem.getParentNode();
		if ((parent == null) || !(parent instanceof Element)) {
			return null;
		}

		String name = parent.getNodeName();
		if (IHTMLConstants.TAG_HTML.equalsIgnoreCase(name)
				|| IHTMLConstants.TAG_BODY.equalsIgnoreCase(name)) {
			return null;
		}

		ITagConverter converter = createTagConverter((Element) parent);
		if (!converter.isVisualByHTML()) {
			return null;
		}

		converter.convertRefresh(null);
		ConvertPosition position = null;
		if (childElem != null) {
			// If a child node (grand child of current parent) was
			// passed in, check for its position. It may have been
			// moved up a level to child model list of the current
			// parent. In JSF this is done with a header or
			// footer facet tag in a column tag for a dataTable.
			position = converter.getChildVisualPosition(childElem);
		}
		if (position == null) {
			position = converter.getChildVisualPosition(srcElem);
		}
		if (position != null) {
			// return the node that will contain the visual
			// child and then the caller can check to see if this
			// element is table mark-up.
			return position.getParentNode();
		}

		// The current source element is not in the child model
		// list for the converted parent so recurse to next
		// ancestor and pass source element to see if it has been
		// moved up a level as child model of the grandparent.
		return findConvertedParentElement((Element) parent, srcElem);
	}

	private static ITagConverter createTagConverter(Element ele) {
		return DTManager.getInstance().getTagConverter(ele,
				IConverterFactory.MODE_DESIGNER, null);
	}
}