/*
 * $Id: XmlUtil.java,v 1.3 2011/03/24 16:06:35 davep Exp $
 *
 * This file is part of McIDAS-V
 *
 * Copyright 2007-2011
 * Space Science and Engineering Center (SSEC)
 * University of Wisconsin - Madison
 * 1225 W. Dayton Street, Madison, WI 53706, USA
 * https://www.ssec.wisc.edu/mcidas
 * 
 * All Rights Reserved
 * 
 * McIDAS-V is built on Unidata's IDV and SSEC's VisAD libraries, and
 * some McIDAS-V source code is based on IDV and VisAD source code.  
 * 
 * McIDAS-V is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * McIDAS-V 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 Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser Public License
 * along with this program.  If not, see http://www.gnu.org/licenses.
 */






package edu.wisc.ssec.mcidasv.util;


import java.util.ArrayList;
import java.util.List;

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;



/**
 * A collection of utilities for xml.
 *
 * @author IDV development team
 */

public abstract class XmlUtil extends ucar.unidata.xml.XmlUtil {

        /**
         * Print all the attributes of the given node
         * 
         * @param parent
         */
        public static void printNode(Node parent) {
                if (parent==null) {
                        System.out.println("null node!");
                        return;
                }
                System.out.println(parent.getNodeName() + " node:");
                NamedNodeMap attrs = parent.getAttributes();
                for(int i = 0 ; i<attrs.getLength() ; i++) {
                        Attr attribute = (Attr)attrs.item(i);     
                        System.out.println("  " + attribute.getName()+" = "+attribute.getValue());
                }
        }

    /**
     *  Find all of the  descendant elements of the given parent Node
     *  whose tag name.equals the given tag.
     *
     *  @param parent The root of the xml dom tree to search.
     *  @param tag The tag name to match.
     *  @return The list of descendants that match the given tag.
     */
    public static List<String> findDescendantNamesWithSeparator(Node parent, String tag, String separator) {
        ArrayList<String> found = new ArrayList<String>();
        findDescendantNamesWithSeparator(parent, tag, "", separator, found);
        return found;
    }
    
    /**
     *  Find all of the  descendant elements of the given parent Node
     *  whose tag name equals the given tag.
     *
     *  @param parent The root of the xml dom tree to search.
     *  @param tag The tag name to match.
     *  @param found The list of descendants that match the given tag.
     */
    private static void findDescendantNamesWithSeparator(Node parent, String tag, String descendants, String separator, List<String> found) {
            if (parent instanceof Element) {
                String elementName = ((Element)parent).getAttribute("name");
                if (!elementName.equals(""))
                        descendants += ((Element)parent).getAttribute("name");
                if (parent.getNodeName().equals(tag)) {
                found.add(descendants);
                }
                if (!elementName.equals(""))
                        descendants += separator;
        }
        NodeList children = parent.getChildNodes();
        for (int i = 0; i < children.getLength(); i++) {
            Node child = children.item(i);
                findDescendantNamesWithSeparator(child, tag, descendants, separator, found);
        }
    }
    
    /**
     * Find the element described by nameList (path)
     * 
     * @param parent
     * @param nameList
     * @return
     */
    public static Element getElementAtNamedPath(Node parent, List<String>nameList) {
        return getMakeElementAtNamedPath(parent, nameList, "", false);
    }
    
    /**
     * Make the element described by nameList (path)
     * 
     * @param parent
     * @param nameList
     * @return
     */
    public static Element makeElementAtNamedPath(Node parent, List<String>nameList, String tagname) {
        return getMakeElementAtNamedPath(parent, nameList, tagname, true);
    }
    
    /**
     * Find the element described by nameList (path)
     * 
     * @param parent
     * @param nameList
     * @return
     */
    public static Element getMakeElementAtNamedPath(Node parent, List<String>nameList, String tagName, boolean makeNew) {
        Element thisElement = null;
        if (parent instanceof Element && nameList.size() > 0) {
                for (int i=0; i<nameList.size(); i++) {
                        String thisName = nameList.get(i);
                        NodeList children = parent.getChildNodes();
                        boolean foundChild = false;
                        for (int j=0; j<children.getLength(); j++) {
                                Node child = children.item(j);
                                if (!(child instanceof Element)) continue;
                                if (XmlUtil.getAttribute(child, "name").equals(thisName)) {
                                        if (i == nameList.size()-1) thisElement = (Element)child;
                                        parent = child;
                                        foundChild = true;
                                        break;
                                }
                        }
                        
                        // Didn't find it where we expected to.  Create a new one.
                        if (makeNew && !foundChild && parent instanceof Element) {
                                try {
                                        Element newElement = XmlUtil.create(tagName, (Element)parent);
                                        newElement.setAttribute("name", thisName);
                                        parent.appendChild(newElement);
                                        parent = newElement;
                                        thisElement = newElement;
                                }
                                catch (Exception ex) {
                                        System.err.println("Error making new " + tagName + " node named " + thisName);
                                        break;
                                }
                        }
                        
                }
        }
        
        return thisElement;
    }
    
}