/*
 * Copyright  1999-2004 The Apache Software Foundation.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */
package org.apache.xml.security.samples.signature;



import org.apache.xml.security.signature.XMLSignatureInput;
import org.apache.xml.security.utils.resolver.ResourceResolverException;
import org.apache.xml.security.utils.resolver.ResourceResolverSpi;
import org.w3c.dom.Attr;


/**
 * This is a sample ResourceResolver who demonstrated how References without
 * URI attribuet could be handled.
 *
 * @author $Author: blautenb $
 */
public class NullURIReferenceResolver extends ResourceResolverSpi {

   /** {@link org.apache.commons.logging} logging facility */
    static org.apache.commons.logging.Log log = 
        org.apache.commons.logging.LogFactory.getLog(
                NullURIReferenceResolver.class.getName());

   /** Field _data[] */
   byte _data[] = null;

   /** Field _data2[][] */
   byte _data2[][] = null;

   /** Field _count */
   int _count = -1;

   /**
    * Constructor NullURIReferenceResolver
    *
    * @param data
    */
   public NullURIReferenceResolver(byte[] data) {
      _data = data;
      _count = -1;
   }

   /**
    * Constructor NullURIReferenceResolver
    *
    * @param data
    */
   public NullURIReferenceResolver(byte[][] data) {
      _data2 = data;
      _count = 0;
   }

   /**
    * Method engineResolve
    *
    * @param uri
    * @param BaseURI
    *
    * @throws ResourceResolverException
    */
   public XMLSignatureInput engineResolve(Attr uri, String BaseURI)
           throws ResourceResolverException {

      XMLSignatureInput result = null;

      if ((this._data != null) && (this._count == -1)) {

         // we always return the same stuff;
         result = new XMLSignatureInput(this._data);

         result.setSourceURI("memory://null");
         result.setMIMEType("text/txt");
      } else if ((this._data == null) && (this._count != -1)) {
         if (this._count < this._data2.length) {
            result = new XMLSignatureInput(this._data2[this._count]);

            result.setSourceURI("memory://" + this._count);

            this._count++;

            result.setMIMEType("text/txt");
         } else {
            String errMsg = "You did not supply enough data!!! There are only "
                            + (this._data2.length) + " byte[] arrays";
            Object exArgs[] = { errMsg };

            throw new ResourceResolverException("empty", exArgs, uri, BaseURI);
         }
      } else {
         Object exArgs[] = { "You did not supply data !!!" };

         throw new ResourceResolverException("empty", exArgs, uri, BaseURI);
      }

      return result;
   }

   /**
    * Method engineCanResolve
    *
    * @param uri
    * @param BaseURI
    *
    */
   public boolean engineCanResolve(Attr uri, String BaseURI) {

      if (uri == null) {
         if ((this._data != null) && (this._count == -1)) {
            return true;
         } else if ((this._data == null) && (this._count != -1)) {
            return true;
         }
      }

      return false;
   }

   /**
    * Method engineGetPropertyKeys
    *
    *
    */
   public String[] engineGetPropertyKeys() {
      return null;
   }
}