source: trunk/gli/src/org/greenstone/gatherer/valuetree/GValueModel.java@ 4364

package org.greenstone.gatherer.valuetree;
/**
 *#########################################################################
 *
 * A component of the Gatherer application, part of the Greenstone digital
 * library suite from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * <BR><BR>
 *
 * Author: John Thompson, Greenstone Digital Library, University of Waikato
 *
 * <BR><BR>
 *
 * Copyright (C) 1999 New Zealand Digital Library Project
 *
 * <BR><BR>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * <BR><BR>
 *
 * This program 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 General Public License for more details.
 *
 * <BR><BR>
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *########################################################################
 */
import java.util.*;
import javax.swing.tree.*;
import org.greenstone.gatherer.Gatherer;
import org.greenstone.gatherer.msm.ElementWrapper;
import org.greenstone.gatherer.msm.MetadataSetManager;
import org.greenstone.gatherer.msm.MSMUtils;
import org.greenstone.gatherer.util.SynchronizedTreeModelTools;
import org.greenstone.gatherer.util.Utility;
import org.w3c.dom.*;
/*
 * @author John Thompson, Greenstone Digital Library, University of Waikato
 * @version 2.1
 */
public class GValueModel 
    extends DefaultTreeModel {

    private ElementWrapper element;

    public GValueModel() {
    super(new DefaultMutableTreeNode("Temp"));
    }

    public GValueModel(String root) {
    super(new DefaultMutableTreeNode(root));
    }

    public GValueModel(ElementWrapper e) {
    super(new DefaultMutableTreeNode("Temp"));
    this.element = e;
    // Load the template value tree document.
    Document document = MSMUtils.getValueTreeTemplate();
    Element new_root = document.getDocumentElement();
    new_root.setAttribute("element", e.getName());
    root = new GValueNode(new_root);
    }

    public GValueModel(ElementWrapper e, Document document) {
    super(new DefaultMutableTreeNode("Temp"));
    this.element = e;
    Element new_root = document.getDocumentElement();
    new_root.setAttribute("element", e.getName());
    root = new GValueNode(new_root);
    }

    /** Value may include path ie news/newssw */
    public GValueNode addValue(String value) {
    ///ystem.err.println("Adding value to valuetree: " + value);
    StringTokenizer tokenizer = new StringTokenizer(value, "\\");
    GValueNode subject = (GValueNode) root;
    while(tokenizer.hasMoreTokens() && subject != null) {
        String token = tokenizer.nextToken();
        subject = addValue(token, subject, null);
                ///ystem.err.println("Found or created a node " + token);
    }
    return subject;
    }

    public GValueNode addValue(String value, GValueNode subject, String alias) {
    // To add a value we must first ensure it isn't already present in -this- nodes children. The bummer is that the nice getElements functions search the whole tree so...
    GValueNode value_node = subject.getValue(Utility.stripNL(value));
    if(value_node == null) {
                // Now add the new value.
        Document document = subject.getElement().getOwnerDocument();
                // Now we create a new subject and add it subject
        Element new_subject = document.createElementNS("","Subject");
        Element new_value = document.createElementNS("","Value");
        new_subject.appendChild(new_value);
        Text new_text = document.createTextNode(value);
        new_value.appendChild(new_text);
        if(alias != null && alias.length() > 0) {
        Element new_alias = document.createElementNS("","Alias");
        new_subject.appendChild(new_alias);
        Text new_alias_text = document.createTextNode(alias);
        new_alias.appendChild(new_alias_text);                  
        } 
        value_node = new GValueNode(new_subject);
                // Figure out where this node will be inserted in subjects 
                // children.
        int position = -1;
        for(int i = 0; position == -1 && i < subject.getChildCount(); i++) {
        Object sibling = subject.getChildAt(i);
        int rel_pos = value.compareTo(sibling.toString());
        ///ystem.err.println("'"+value+"'.compareTo('"+sibling+"') = " + rel_pos);
        if(rel_pos <= 0) {
            position = i;
        }
        }
        if(position == -1) {
        position = subject.getChildCount();
        }
                // Insert it. If position is still -1, append it to the end of subjects children.
                ///ystem.err.println("Inserting '" + value + "' at position " + position);
        insertNodeInto(value_node, subject, position);
                // Inform listeners that we've changed.
        Gatherer.c_man.getCollection().msm.fireValueChanged(element, null, this);
    }
    return value_node;
    }

    public Document getDocument() {
    return ((GValueNode)root).getElement().getOwnerDocument();
    }

    public ElementWrapper getElement() {
    return element;
    }

    /** Retrieve the hindex for a certain value within the value tree.
     * @param value The value whose index you wish to determine as a <strong>String</strong>.
     * @return A <strong>String</strong> containing an index such as "1", "2.1" or "18.2.5".
     */ 
    public String getHIndex(String value) {
    ///ystem.err.println("getHIndex(" + value + ")");
    return getHIndex((GValueNode) root, value, null);
    }

    /** Retrieve a value node given its hierarchical reference or value.
     * @param index The hierarchy index or value as a <strong>String</strong>.
     */
    public GValueNode getValue(String index_str) {
    ///ystem.err.println("Retrieve the value for: " + index_str);
    GValueNode result = null;
    if(isHierarchy() && Utility.isIndex(index_str)) {
                // StringTokenize the index
        StringTokenizer tokenizer = new StringTokenizer(index_str, ".");
        result = (GValueNode) root;
                // Using the index numbers retrieve the appropriate node.
        try {
        while(result != null && tokenizer.hasMoreTokens()) {
            int index = Integer.parseInt(tokenizer.nextToken()) - 1;
            // Retrieve the index'th child of the current result node
            if(0 <= index && index < result.getChildCount()) {
            result = (GValueNode) result.getChildAt(index);
            }
            // Otherwise we're broken.
            else {
            ///ystem.err.println("There is no " + index + "th childnode of " + result);
            result = null;
            }
        }
        }
                // Most likely caused by parseInt throwing a wobbly.
        catch (Exception error) {
        result = null;
        }
        if(result != null) {
        // Ensure result is enabled
        result.setEnabled(true);
        }
    }
    if(result == null) {
                ///ystem.err.println("No existing value. Adding " + index_str);
        result = addValue(index_str);
    }
    return result;
    }

    public boolean isHierarchy() {
    boolean result = false;
    // We are a hierarchy if our element says so....
    if(element.isHierarchy()) {
        return true;
    }
    // Or if our children are actually a hierarchy.
    for(int i = 0; i < root.getChildCount() && !result; i++) {
        GValueNode node = (GValueNode) root.getChildAt(i);
        if(node != null && node.getChildCount() > 0) {
        result = true;
        }
    }
    return result;
    }

    public void removeValue(GValueNode child) {
    child.setEnabled(false); // Doesn't appear anymore.
    SynchronizedTreeModelTools.removeNodeFromParent(this, child);
    Gatherer.c_man.getCollection().msm.fireValueChanged(new ElementWrapper(child.getElement()), null, this);
    }

    public void removeValue(String value) {
    // Retrieve the node to be removed.
    GValueNode node = getValue(value);
    // Now remove it
    removeNodeFromParent(node);
    }

    /** Called to remove a certain value of metadata within a specific
     * subject within a sbject hierarchy. 
     * Note that this method currently doesn't do anything.
     * @param value A String representing the value to be removed.
     * @param subject An Element representing the subject you wish to remove 
     * this value from.
     */ 
    public void removeValue(String value, GValueNode subject) {
    }

    public int size() {
    return size(root);
    }

    private int size(TreeNode current) {
    int size = 1;
    for(int i = 0; i < current.getChildCount(); i++) {
        size = size + size(current.getChildAt(i));
    }
    return size;
    }

    public String toString() {
    return element.toString();
    }

    public Vector traverseTree() {
    Vector contents = new Vector();
    contents.addAll(traverseTree((GValueNode) root));
    contents.remove((GValueNode) root);
    return contents;
    }

    public void updateValue(String new_value, String old_value) {
    ///ystem.err.println("Updating '" + old_value + "' to '" + new_value + "'"); 
    StringTokenizer tokenizer = new StringTokenizer(new_value, "\\");
    GValueNode subject = (GValueNode) root;
    while(tokenizer.hasMoreTokens()) {
        String token = tokenizer.nextToken();
        subject = updateValue(token, old_value, subject);
    }
    }

    /** Called to update a certain value of metadata within a specific
     * subject within a sbject hierarchy. 
     * Note that this simply in turn calls removeValue() to deal with the
     * old value, then addValue() to account for the new. 
     * @param new_value A String representing the updated value.
     * @param old_value A String representing the old value.
     * @param subject An Element representing the subject you wish to update 
     * this value in.
     */ 
    public GValueNode updateValue(String new_value, String old_value, GValueNode subject) {
    return addValue(new_value, subject, null);
    }

    private GValueModel copy() {
    Element document_element = ((GValueNode) root).getElement();
    Document document_copy = MSMUtils.getValueTreeTemplate();
    Element document_copy_element = document_copy.getDocumentElement();
    document_copy_element.setAttribute("element", element.getName());
    for(Node node = document_element.getFirstChild(); node != null; node = node.getNextSibling()) {
        if(node.getNodeName().equals("Subject")) {
        Node node_copy = document_copy.importNode(node, true);
        document_copy_element.appendChild(node_copy);
        }
    }
    return new GValueModel(element, document_copy);                 
    }

    private String getHIndex(GValueNode node, String value, String index) {
    for(int i = node.size(); i != 0; i--) {
        GValueNode next = (GValueNode)node.get(i - 1);
        String next_str = next.toString();
        if(value.startsWith(next_str)) {
        if(index == null) {
            index = String.valueOf(i);
        }
        else {
            index = index + "." + i;
        }
        value = value.substring(next.toString().length());
        if(value.startsWith("\\")) {
            value = value.substring(1);
            index = getHIndex(next, value, index);
        }
        return index;
        }
    }
    return index;
    }

    private Vector traverseTree(GValueNode node) {
    Vector contents = new Vector();
    contents.add(node);
    for(int i = 0; i < node.getChildCount(); i++) {
        contents.addAll(traverseTree((GValueNode)node.getChildAt(i)));
    }
    return contents;
    }
}