/*
 * 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 java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.security.PublicKey;
import java.security.cert.X509Certificate;

import org.apache.xml.security.keys.KeyInfo;
import org.apache.xml.security.samples.utils.resolver.OfflineResolver;
import org.apache.xml.security.signature.XMLSignature;
import org.apache.xml.security.samples.SampleUtils;
import org.apache.xml.security.utils.Constants;
import org.apache.xml.security.utils.XMLUtils;
import org.apache.xpath.XPathAPI;
import org.w3c.dom.Element;


/**
 *
 *
 *
 *
 * @author $Author: mullan $
 *
 */
public class VerifySignature {

   /**
    * Method main
    *
    * @param unused
    */
   public static void main(String unused[]) {

      boolean schemaValidate = false;
      final String signatureSchemaFile = "data/xmldsig-core-schema.xsd";
      // String signatureFileName = "data/ie/baltimore/merlin-examples/merlin-xmldsig-fifteen/signature-enveloping-rsa.xml";
      String signatureFileName = "signature.xml";

      if (schemaValidate) {
         System.out.println("We do schema-validation");
      }

      javax.xml.parsers.DocumentBuilderFactory dbf =
         javax.xml.parsers.DocumentBuilderFactory.newInstance();

      if (schemaValidate) {
         dbf.setAttribute("http://apache.org/xml/features/validation/schema",
                          Boolean.TRUE);
         dbf.setAttribute(
            "http://apache.org/xml/features/dom/defer-node-expansion",
            Boolean.TRUE);
         dbf.setValidating(true);
         dbf.setAttribute("http://xml.org/sax/features/validation",
                          Boolean.TRUE);
      }

      dbf.setNamespaceAware(true);
      dbf.setAttribute("http://xml.org/sax/features/namespaces", Boolean.TRUE);

      if (schemaValidate) {
         dbf.setAttribute(
            "http://apache.org/xml/properties/schema/external-schemaLocation",
            Constants.SignatureSpecNS + " " + signatureSchemaFile);
      }

      try {

         // File f = new File("signature.xml");
         File f = new File(signatureFileName);

         System.out.println("Try to verify " + f.toURL().toString());

         javax.xml.parsers.DocumentBuilder db = dbf.newDocumentBuilder();

         db.setErrorHandler(new org.apache.xml.security.utils
            .IgnoreAllErrorHandler());

         if (schemaValidate) {
            db.setEntityResolver(new org.xml.sax.EntityResolver() {

               public org.xml.sax.InputSource resolveEntity(
                       String publicId, String systemId)
                          throws org.xml.sax.SAXException {

                  if (systemId.endsWith("xmldsig-core-schema.xsd")) {
                     try {
                        return new org.xml.sax.InputSource(
                           new FileInputStream(signatureSchemaFile));
                     } catch (FileNotFoundException ex) {
                        throw new org.xml.sax.SAXException(ex);
                     }
                  } else {
                     return null;
                  }
               }
            });
         }

         org.w3c.dom.Document doc = db.parse(new java.io.FileInputStream(f));
         Element nscontext = SampleUtils.createDSctx(doc, "ds",
                                                  Constants.SignatureSpecNS);
         Element sigElement = (Element) XPathAPI.selectSingleNode(doc,
                                 "//ds:Signature[1]", nscontext);
         XMLSignature signature = new XMLSignature(sigElement,
                                                   f.toURL().toString());

         signature.addResourceResolver(new OfflineResolver());

         // XMLUtils.outputDOMc14nWithComments(signature.getElement(), System.out);
         KeyInfo ki = signature.getKeyInfo();

         if (ki != null) {
            if (ki.containsX509Data()) {
               System.out
                  .println("Could find a X509Data element in the KeyInfo");
            }

            X509Certificate cert = signature.getKeyInfo().getX509Certificate();

            if (cert != null) {
               /*
               System.out.println(
                  "I try to verify the signature using the X509 Certificate: "
                  + cert);
               */
               System.out.println("The XML signature in file "
                                  + f.toURL().toString() + " is "
                                  + (signature.checkSignatureValue(cert)
                                     ? "valid (good)"
                                     : "invalid !!!!! (bad)"));
            } else {
               System.out.println("Did not find a Certificate");

               PublicKey pk = signature.getKeyInfo().getPublicKey();

               if (pk != null) {
                  /*
                  System.out.println(
                     "I try to verify the signature using the public key: "
                     + pk);
                  */
                  System.out.println("The XML signature in file "
                                     + f.toURL().toString() + " is "
                                     + (signature.checkSignatureValue(pk)
                                        ? "valid (good)"
                                        : "invalid !!!!! (bad)"));
               } else {
                  System.out.println(
                     "Did not find a public key, so I can't check the signature");
               }
            }
         } else {
            System.out.println("Did not find a KeyInfo");
         }
      } catch (Exception ex) {
         ex.printStackTrace();
      }
   }

   static {
      org.apache.xml.security.Init.init();
   }
}
