/*
 * Copyright 2006-2009 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.
 *
 */
/*
 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
 */
package javax.xml.crypto.test.dsig;

import java.io.*;
import java.security.*;
import java.security.spec.*;
import java.util.*;
import javax.crypto.SecretKey;
import javax.xml.crypto.dsig.*;
import javax.xml.crypto.dsig.dom.DOMValidateContext;
import javax.xml.crypto.dsig.spec.*;
import javax.xml.crypto.dom.*;
import javax.xml.crypto.*;
import java.math.BigInteger;
import javax.xml.transform.*;
import javax.xml.transform.dom.*;
import javax.xml.transform.stream.StreamResult;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.*;

/*
 * @author Sean Mullan
 * @author Valerie Peng
 */
public class TestUtils {
    
    private static final String DSA_Y = "07066284216756577193658833512863439617178933165631848358445549382240081120085333137303066923542492834619027404463194956043802393462371310375123430985057160";
    private static final String DSA_P = "013232376895198612407547930718267435757728527029623408872245156039757713029036368719146452186041204237350521785240337048752071462798273003935646236777459223";
    private static final String DSA_Q = "0857393771208094202104259627990318636601332086981";
    private static final String DSA_G = "05421644057436475141609648488325705128047428394380474376834667300766108262613900542681289080713724597310673074119355136085795982097390670890367185141189796";
    private static final String DSA_X = "0527140396812450214498055937934275626078768840117";
    private static final String RSA_MOD = "010800185049102889923150759252557522305032794699952150943573164381936603255999071981574575044810461362008102247767482738822150129277490998033971789476107463";
    private static final String RSA_PUB = "065537";
    private static final String RSA_PRIV = "0161169735844219697954459962296126719476357984292128166117072108359155865913405986839960884870654387514883422519600695753920562880636800379454345804879553";

    private TestUtils() {}
    
    public static PublicKey getPublicKey(String algo) 
	throws InvalidKeySpecException, NoSuchAlgorithmException {
	KeyFactory kf = KeyFactory.getInstance(algo);
	KeySpec kspec;
	if (algo.equalsIgnoreCase("DSA")) {
	    kspec = new DSAPublicKeySpec(new BigInteger(DSA_Y), 
					 new BigInteger(DSA_P), 
					 new BigInteger(DSA_Q), 
					 new BigInteger(DSA_G));
	} else if (algo.equalsIgnoreCase("RSA")) {
	    kspec = new RSAPublicKeySpec(new BigInteger(RSA_MOD), 
					 new BigInteger(RSA_PUB));
	} else throw new RuntimeException("Unsupported key algorithm " + algo);
	return kf.generatePublic(kspec);
    }

    public static PrivateKey getPrivateKey(String algo) 
	throws InvalidKeySpecException, NoSuchAlgorithmException {
	KeyFactory kf = KeyFactory.getInstance(algo);
	KeySpec kspec;
	if (algo.equalsIgnoreCase("DSA")) {
	    kspec = new DSAPrivateKeySpec
		(new BigInteger(DSA_X), new BigInteger(DSA_P), 
		 new BigInteger(DSA_Q), new BigInteger(DSA_G));
	} else if (algo.equalsIgnoreCase("RSA")) {
	    kspec = new RSAPrivateKeySpec
		(new BigInteger(RSA_MOD), new BigInteger(RSA_PRIV));
	} else throw new RuntimeException("Unsupported key algorithm " + algo);
	return kf.generatePrivate(kspec);
    }

    public static SecretKey getSecretKey(final byte[] secret) {
	return new SecretKey() {
	    public String getFormat()	{ return "RAW"; }
	    public byte[] getEncoded()	{ return secret; }
	    public String getAlgorithm(){ return "SECRET"; }
	};
    }
    
    public static Document newDocument() {
	try {
	    DocumentBuilderFactory docFac =
                DocumentBuilderFactory.newInstance();
	    docFac.setNamespaceAware(true);
            DocumentBuilder docBuilder = docFac.newDocumentBuilder();
	    return docBuilder.newDocument();
	} catch (Exception ex) {
	    return null;
	}
    }

    public static class MyOwnC14nParameterSpec implements C14NMethodParameterSpec {}
    
    public static class MyOwnDigestMethodParameterSpec 
	implements DigestMethodParameterSpec {}
    
    public static class MyOwnSignatureMethodParameterSpec 
	implements SignatureMethodParameterSpec {}

    public static XMLValidateContext getXMLValidateContext(String type, 
						       File input, 
						       String tag) 
	throws Exception {
	if (type.equalsIgnoreCase("dom")) {
	    DocumentBuilderFactory docFactory =
		DocumentBuilderFactory.newInstance();
	    DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
	    Document doc = docBuilder.parse(input);
	    if (tag == null) {
		return new DOMValidateContext
		    (TestUtils.getPublicKey("RSA"), doc.getDocumentElement());
	    } else {
		NodeList list = doc.getElementsByTagName(tag);
		return new DOMValidateContext
		    (TestUtils.getPublicKey("RSA"), list.item(0));
	    }
	} else {
	    throw new Exception("Unsupported XMLValidateContext type: " + 
				type);
	}
    }

    public static class MyOwnDOMReference extends DOMStructure 
	implements Reference {
	private String id;
	private boolean status;
	private byte[] digest;
	private static MessageDigest MD;
	private static DigestMethod DIG_METHOD;
	private Data derefData;
	private InputStream dis;
	static {
	    try {
		MD = MessageDigest.getInstance("SHA");
		XMLSignatureFactory factory = XMLSignatureFactory.getInstance
       		    ("DOM", new org.jcp.xml.dsig.internal.dom.XMLDSigRI());
		DIG_METHOD = 
		    factory.newDigestMethod(DigestMethod.SHA1, null);
	    } catch (Exception ex) {
		// should never be thrown
	    }
	};
	
	public MyOwnDOMReference(String id, boolean status) {
	    super(newDocument());
	    this.id = id;
	    this.status = status;
	    digest = null;
	}

	public byte[] getDigestValue() {
	    if (digest == null) {
		byte[] inBytes = id.getBytes();
		digest = new byte[20];
		if (status) {
		    digest = MD.digest(inBytes);
		}
	    }
	    return digest;
	}
	public byte[] getCalculatedDigestValue() {
	    return null;
	}
	public DigestMethod getDigestMethod() { return DIG_METHOD; }
	public String getId() {
	    return id;
	}
	public String getType() {
	    return null;
	}
	public String getURI() {
	    return null;
	}
	public List getTransforms() {
	    return Collections.EMPTY_LIST;
	}
	public boolean validate(XMLValidateContext vCtx) 
	    throws XMLSignatureException {
	    this.dis = new ByteArrayInputStream(id.getBytes());
	    this.derefData = new OctetStreamData(this.dis);
	    return status;
	}
	public Data getDereferencedData() {
	    return derefData;
	}
	public InputStream getDigestInputStream() {
	    return dis;
        }
    }

    public static class MyOwnXMLStructure implements XMLStructure {
	public boolean isFeatureSupported(String feature) 
	    throws NullPointerException {
	    if (feature == null) throw new NullPointerException();
	    return false;
	}
    }

    public static class OctetStreamURIDereferencer implements URIDereferencer {
        private byte[] data = null;
        public OctetStreamURIDereferencer(byte[] in) {
            data = (byte[]) in.clone();
        }
        public Data dereference(URIReference ref, XMLCryptoContext ctxt) {
            return new OctetStreamData(new ByteArrayInputStream(data));
        }
        public byte[] getData() {
            return data;
        }
        public boolean equals(Object obj) {
            if (obj instanceof OctetStreamURIDereferencer) {
                return Arrays.equals
                    (((OctetStreamURIDereferencer) obj).getData(), data);
            } else {
                return false;
            }
        }
        public int hashCode() {
            return 5678;
        }
    }

    public static class NodeSetURIDereferencer implements URIDereferencer {
        private Node data = null;
        public NodeSetURIDereferencer(Node node) {
            data = node;
        }
        public Data dereference(URIReference ref, XMLCryptoContext ctxt) {
            return new NodeSetData() {
                public Iterator iterator() {
                    return Collections.singletonList(data).iterator();
                }
            };
        }
    }

    public static void dumpDocument(Document doc, String outName)
	throws Exception {
        DOMSource source = new DOMSource(doc);
	File path = new File(System.getProperty("test.dir"), outName);
        Result result = new StreamResult(new FileOutputStream(path));
        Transformer trans = TransformerFactory.newInstance().newTransformer();
        trans.setOutputProperty(OutputKeys.INDENT, "yes");
        trans.transform(source, result);
    }
}