/*
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 */
/*
 * $Id: DOMXMLSignatureFactory.java,v 1.21 2005/09/23 19:59:11 mullan Exp $
 */
package org.jcp.xml.dsig.internal.dom;

import javax.xml.crypto.*;
import javax.xml.crypto.dsig.*;
import javax.xml.crypto.dsig.dom.DOMValidateContext;
import javax.xml.crypto.dsig.keyinfo.*;
import javax.xml.crypto.dsig.spec.*;

import java.security.*;
import java.security.spec.AlgorithmParameterSpec;
import java.util.List;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;

/**
 * DOM-based implementation of XMLSignatureFactory.
 *
 * @author Sean Mullan
 */
public final class DOMXMLSignatureFactory extends XMLSignatureFactory {

    /**
     * Initializes a new instance of this class.
     */
    public DOMXMLSignatureFactory() {}

    public XMLSignature newXMLSignature(SignedInfo si, KeyInfo ki) {
	return new DOMXMLSignature(si, ki, null, null, null);
    }

    public XMLSignature newXMLSignature(SignedInfo si, KeyInfo ki,
        List objects, String id, String signatureValueId) {
	return new DOMXMLSignature(si, ki, objects, id, signatureValueId);
    }

    public Reference newReference(String uri, DigestMethod dm) {
	return newReference(uri, dm, null, null, null);
    }

    public Reference newReference(String uri, DigestMethod dm, List transforms,
        String type, String id) {
	return new DOMReference(uri, type, dm, transforms, id);
    }

    public Reference newReference(String uri, DigestMethod dm, 
	List appliedTransforms, Data result, List transforms, String type, 
	String id) {
	if (appliedTransforms == null) {
	    throw new NullPointerException("appliedTransforms cannot be null");
	}
	if (appliedTransforms.isEmpty()) {
	    throw new NullPointerException("appliedTransforms cannot be empty");
	}
	if (result == null) {
	    throw new NullPointerException("result cannot be null");
	}
	return new DOMReference
	    (uri, type, dm, appliedTransforms, result, transforms, id);
    }

    public Reference newReference(String uri, DigestMethod dm, List transforms,
        String type, String id, byte[] digestValue) {
	if (digestValue == null) {
	    throw new NullPointerException("digestValue cannot be null");
	}
	return new DOMReference
	    (uri, type, dm, null, null, transforms, id, digestValue);
    }

    public SignedInfo newSignedInfo(CanonicalizationMethod cm,
	SignatureMethod sm, List references) {
	return newSignedInfo(cm, sm, references, null);
    }

    public SignedInfo newSignedInfo(CanonicalizationMethod cm,
	SignatureMethod sm, List references, String id) {
	return new DOMSignedInfo(cm, sm, references, id);
    }

    // Object factory methods
    public XMLObject newXMLObject(List content, String id, String mimeType,
	String encoding) {
	return new DOMXMLObject(content, id, mimeType, encoding);
    }

    public Manifest newManifest(List references) {
	return newManifest(references, null);
    }

    public Manifest newManifest(List references, String id) {
	return new DOMManifest(references, id);
    }

    public SignatureProperties newSignatureProperties(List props, String id) {
	return new DOMSignatureProperties(props, id);
    }

    public SignatureProperty newSignatureProperty
	(List info, String target, String id) {
	return new DOMSignatureProperty(info, target, id);
    }

    public XMLSignature unmarshalXMLSignature(XMLValidateContext context)
        throws MarshalException {

        if (context == null) {
            throw new NullPointerException("context cannot be null");
        }
	return unmarshal(((DOMValidateContext) context).getNode(), context);
    }

    public XMLSignature unmarshalXMLSignature(XMLStructure xmlStructure)
        throws MarshalException {

        if (xmlStructure == null) {
            throw new NullPointerException("xmlStructure cannot be null");
        }
	return unmarshal
	    (((javax.xml.crypto.dom.DOMStructure) xmlStructure).getNode(), 
	     null);
    }

    private XMLSignature unmarshal(Node node, XMLValidateContext context) 
	throws MarshalException {

        node.normalize();
        
        Element element = null;
        if (node.getNodeType() == Node.DOCUMENT_NODE) {
            element = ((Document) node).getDocumentElement();
        } else if (node.getNodeType() == Node.ELEMENT_NODE) {
            element = (Element) node;
        } else {
            throw new MarshalException
		("Signature element is not a proper Node");
        }

        // check tag
        String tag = element.getLocalName();
	if (tag == null) {
	    throw new MarshalException("Document implementation must " +
		"support DOM Level 2 and be namespace aware");
	}
        if (tag.equals("Signature")) {
            return new DOMXMLSignature(element, context);
        } else {
            throw new MarshalException("invalid Signature tag: " + tag);
        }
    }

    public boolean isFeatureSupported(String feature) {
        if (feature == null) {
            throw new NullPointerException();
        } else {
            return false;
        }
    }

    public DigestMethod newDigestMethod(String algorithm,
        DigestMethodParameterSpec params) throws NoSuchAlgorithmException,
        InvalidAlgorithmParameterException {
	if (algorithm == null) {
	    throw new NullPointerException();
	}
        if (algorithm.equals(DigestMethod.SHA1)) {
	    return DOMSHADigestMethod.SHA1(params);
	} else if (algorithm.equals(DigestMethod.SHA256)) {
	    return DOMSHADigestMethod.SHA256(params);
	} else if (algorithm.equals(DigestMethod.SHA512)) {
            return DOMSHADigestMethod.SHA512(params);
	} else {
	    throw new NoSuchAlgorithmException("unsupported algorithm");
	}
    }

    public SignatureMethod newSignatureMethod(String algorithm,
        SignatureMethodParameterSpec params) throws NoSuchAlgorithmException,
        InvalidAlgorithmParameterException {
	if (algorithm == null) {
	    throw new NullPointerException();
	}
	if (algorithm.equals(SignatureMethod.HMAC_SHA1)) {
            return new DOMHMACSignatureMethod(params);
        } else if (algorithm.equals(SignatureMethod.RSA_SHA1)) {
            return new DOMRSASignatureMethod(params);
        } else if (algorithm.equals(SignatureMethod.DSA_SHA1)) {
            return new DOMDSASignatureMethod(params);
	} else {
	    throw new NoSuchAlgorithmException("unsupported algorithm");
	}
    }

    public Transform newTransform(String algorithm,
        TransformParameterSpec params) throws NoSuchAlgorithmException,
        InvalidAlgorithmParameterException {
	TransformService spi = TransformService.getInstance(algorithm, "DOM");
	spi.init(params);
	return new DOMTransform(spi);
    }

    public Transform newTransform(String algorithm,
        XMLStructure params) throws NoSuchAlgorithmException,
        InvalidAlgorithmParameterException {
	TransformService spi = TransformService.getInstance(algorithm, "DOM");
	if (params == null) {
	    spi.init(null);
	} else {
	    spi.init(params, null);
	}
	return new DOMTransform(spi);
    }

    public CanonicalizationMethod newCanonicalizationMethod(String algorithm,
        C14NMethodParameterSpec params) throws NoSuchAlgorithmException,
        InvalidAlgorithmParameterException {
	TransformService spi = TransformService.getInstance(algorithm, "DOM");
	spi.init(params);
	return new DOMCanonicalizationMethod(spi);
    }

    public CanonicalizationMethod newCanonicalizationMethod(String algorithm,
        XMLStructure params) throws NoSuchAlgorithmException,
        InvalidAlgorithmParameterException {
	TransformService spi = TransformService.getInstance(algorithm, "DOM");
	if (params == null) {
	    spi.init(null);
	} else {
	    spi.init(params, null);
	}
	return new DOMCanonicalizationMethod(spi);
    }

    public URIDereferencer getURIDereferencer() {
	return DOMURIDereferencer.INSTANCE;
    }
}