SplitAction.java

/*******************************************************************************
 * Copyright (c) 2004, 2008 John Krasnay 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:
 *     John Krasnay - initial API and implementation
 *******************************************************************************/
package net.sf.vex.action;

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

import net.sf.vex.ToolkitPlugin;
import net.sf.vex.css.CSS;
import net.sf.vex.css.Styles;
import net.sf.vex.dom.Document;
import net.sf.vex.dom.DocumentFragment;
import net.sf.vex.dom.Element;
import net.sf.vex.widget.IVexWidget;

/**
 * Splits the current block element.
 */
public class SplitAction extends AbstractVexAction {

    public void run(final IVexWidget vexWidget) {
        Element element = vexWidget.getCurrentElement();
        Styles styles = vexWidget.getStyleSheet().getStyles(element);
        while (!styles.isBlock()) {
            element = element.getParent();
            styles = vexWidget.getStyleSheet().getStyles(element);
        }
        splitElement(vexWidget, element);
    }


    /**
     * Splits the given element.
     * @param vexWidget IVexWidget containing the document.
     * @param element Element to be split.
     */
    public static void splitElement(final IVexWidget vexWidget, final Element element) {
        
        vexWidget.doWork(new Runnable() {
            public void run() {

            	long start = 0;
            	if (ToolkitPlugin.getInstance().isDebugging()) {
            		start = System.currentTimeMillis();
            	}
                
                Styles styles = vexWidget.getStyleSheet().getStyles(element);
                
                if (styles.getWhiteSpace().equals(CSS.PRE)) {
                    // can't call vexWidget.insertText() or we'll get an infinite loop
                    Document doc = vexWidget.getDocument();
                    int offset = vexWidget.getCaretOffset();
                    doc.insertText(offset, "\n");
                    vexWidget.moveTo(offset + 1);
                } else {
                    
                    // There may be a number of child elements below the given
                    // element. We cut out the tails of each of these elements
                    // and put them in a list of fragments to be reconstructed when
                    // we clone the element.
                    List children = new ArrayList();
                    List frags = new ArrayList();
                    Element child = vexWidget.getCurrentElement();
                    while (true) {
                        children.add(child);
                        vexWidget.moveTo(child.getEndOffset(), true);
                        frags.add(vexWidget.getSelectedFragment());
                        vexWidget.deleteSelection();
                        vexWidget.moveTo(child.getEndOffset() + 1);
                        if (child == element) {
                            break;
                        }
                        child = child.getParent();
                    }

                    for (int i = children.size() - 1; i >= 0; i--) {
                        child = (Element) children.get(i);
                        DocumentFragment frag = (DocumentFragment) frags.get(i);
                        vexWidget.insertElement((Element) child.clone());
                        int offset = vexWidget.getCaretOffset();
                        if (frag != null) {
                            vexWidget.insertFragment(frag);
                        }
                        vexWidget.moveTo(offset);
                    }
                }

                if (ToolkitPlugin.getInstance().isDebugging()) {
                    long end = System.currentTimeMillis();
                    System.out.println("split() took " + (end - start) + "ms");
                }
            }
        });
    }
}