//**************************************************************************

//	Filename 	:	WsTokenHelper.java, WSSE Toolkit 2005

//

//	Author   	:	Denis Pilipchuk

//

//	Purpose  	:	This class holds a reference to the document which

//                  is used to generate XML for tokens.

//

//	Disclaimer: This software is provided "as-is" and does not imply

//              any warranty or responsibility.

//****************************************************************************



package wsse.Toolkit.Tokens;



// W3C DOM includes

import org.w3c.dom.Element;

import org.w3c.dom.Document;

import org.w3c.dom.NodeList;

import org.w3c.dom.Text;



import wsse.Toolkit.Utils.Xml.XmlDocHelper;

import wsse.Toolkit.Utils.Xml.XmlDocException;

import wsse.Toolkit.Utils.Xml.XmlID;

import wsse.Toolkit.Utils.Xml.XmlQName;



import wsse.Toolkit.Utils.Config.ConfigException;

import wsse.Toolkit.Utils.Config.ConfigHelper;



public class WsTokenHelper

{

    public static XmlDocHelper GetDocHelper(String docBuilderFactoryImpl) throws XmlDocException

    {

        XmlDocHelper docHelper = null;

        try

        {

            // Use default config file

            ConfigHelper cfgHelper = ConfigHelper.GetInstance(null);

            // Get the requested DocBuilderFactory implementation (null means default)

            docHelper = cfgHelper.GetXmlFactory().GetDocHelper(docBuilderFactoryImpl);

        }

        catch(ConfigException ce)

        {

            throw new XmlDocException("Error creating xml doc implementation: " + docBuilderFactoryImpl, ce);

        }

        return docHelper;

    }



	public WsTokenHelper(XmlDocHelper docHelper)

	{

		if (null == docHelper)

		{

			throw new NullPointerException("Null document helper passed: " + this);

		}

        m_document = docHelper.GetDocument();

	}



	public WsTokenHelper() throws XmlDocException

	{

		this(WsTokenHelper.GetDocHelper(null));

	}



    ///////////////////////////////////////////////////////////////////////////////////////////////////

    // Convenience instance methods - related to a particular document



	public Element CreateXmlElement(XmlQName qName)

	{

		return m_document.createElementNS(qName.GetNS(),qName.GetPrefixedName());

	}



    public Element CreateXmlElement(XmlQName qName, String value)

    {

        assert null != value : "Element's value can't be null";



        Text textNode = m_document.createTextNode(value);

        Element element = m_document.createElementNS(qName.GetNS(),qName.GetPrefixedName());

        element.appendChild(textNode);



        return element;

    }



    public Element EnsureElementOwner(Element element)

    {

        assert null != element : "Passed element can't be null";



        Document docChild = element.getOwnerDocument();

        // Need to import passed XML Element, if it was created by another document

        Element verifiedElement = docChild == m_document ? element : (Element)m_document.importNode(element, true);



        return verifiedElement;

    }



    public Document GetTokenDocument() { return m_document; }



    ///////////////////////////////////////////////////////////////////////////////////////////////////

    // Convenience static methods - not related to a particular document



    public static Element FindXmlElement(Element source, XmlQName qname, XmlID id)

    {

        if (null == source || null == qname)

        {

            throw new NullPointerException("Name and source parameters should be provided for the search");

        }



        // First, check the source node itself

        Element retElement = qname.IsMatch(source) ? source : null;



        if (null == retElement)

        {

            NodeList nodes = source.getElementsByTagNameNS(qname.GetNS(),

                qname.GetLocalName());

            // If ID was provided, use it in search as well (strict comparison).

            // Otherwise, employ lax comparison by name/ns only, i.e. use the first match

            if (null != id)

            {

                for (int i = 0; null == retElement && i < nodes.getLength(); i++)

                {

                    Element testNode = (Element) nodes.item(i);

                    String idAttr = testNode.getAttributeNS(id.GetNS(), id.GetTag());

                    retElement = null != idAttr && idAttr.equals(id.GetValue()) ?

                        testNode : null;

                }

            }

            else

            {

                retElement = nodes.getLength() > 0 ? (Element) nodes.item(0) : null;

            }

        }



        return retElement;

    }



    public static Element[] FindXmlElements(Element source, XmlQName qname)

    {

        if (null == source || null == qname)

        {

            throw new NullPointerException("All parameters should be provided for the search");

        }



        // Try to find the matching children

        NodeList nodes = source.getElementsByTagNameNS(qname.GetNS(),qname.GetLocalName());

        // Also check the source node itself

        boolean sourceMatch = qname.IsMatch(source);

        Element[] elements = new Element[nodes.getLength() + (sourceMatch ? 1 : 0)];

        for (int i = 0; i < nodes.getLength(); i++)

        {

            elements[i] = (Element) nodes.item(i);

        }

        if (sourceMatch)

        {

            elements[nodes.getLength()] = source;

        }



        return elements;

    }



	private Document m_document;

}