package org.litesoft.GWT.client.dev.ui.inspection.finders;

import java.util.*;

import org.litesoft.GWT.client.dev.ui.inspection.*;

import com.google.gwt.dom.client.*;

public class ElementFinder extends Finder
{
    public ElementFinder(ElementSelectionSpec pSelectionSpec)
    {
        super(pSelectionSpec);
    }
    
    @Override
    protected ElementSelectionSpec getSelectionSpec()
    {
        return (ElementSelectionSpec) super.getSelectionSpec();
    }

    /**
     * Traverse the DOM breadth first, looking for an element which matches the
     * selector's criteria.
     */
    @Override
    public Element find(Element pRoot)
    {
        // TODO: extract traversal logic for reuse? Pull out as an Iterator so compound selectors can pull and pass control around?
        String elementName = getSelectionSpec().getElementName();
        LinkedList<Element> queue = new LinkedList<Element>();
        queue.add(pRoot);
        while (queue.size() > 0)
        {
            Element element = queue.remove(0);
            if (elementName.equals(element.getNodeName()))
            {
                return element;
            }
            else
            {
                Element sibling = element.getFirstChildElement();
                while (sibling != null)
                {
                    queue.add(sibling);
                    sibling = sibling.getNextSiblingElement();
                }
            }
        }
        return null;
    }
}