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package com.sun.xml.internal.ws.encoding;

import com.sun.xml.internal.ws.api.SOAPVersion;
import com.sun.xml.internal.ws.api.WSFeatureList;
import com.sun.xml.internal.ws.api.client.SelectOptimalEncodingFeature;
import com.sun.xml.internal.ws.api.fastinfoset.FastInfosetFeature;
import com.sun.xml.internal.ws.api.message.Message;
import com.sun.xml.internal.ws.api.message.Packet;
import com.sun.xml.internal.ws.api.message.ExceptionHasMessage;
import com.sun.xml.internal.ws.api.pipe.Codec;
import com.sun.xml.internal.ws.api.pipe.Codecs;
import com.sun.xml.internal.ws.api.pipe.ContentType;
import com.sun.xml.internal.ws.api.pipe.StreamSOAPCodec;
import com.sun.xml.internal.ws.client.ContentNegotiation;
import com.sun.xml.internal.ws.protocol.soap.MessageCreationException;
import com.sun.xml.internal.ws.resources.StreamingMessages;
import com.sun.xml.internal.ws.server.UnsupportedMediaException;
import static com.sun.xml.internal.ws.binding.WebServiceFeatureList.getSoapVersion;

import javax.xml.ws.WebServiceException;
import javax.xml.ws.WebServiceFeature;
import javax.xml.ws.soap.MTOMFeature;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.WritableByteChannel;
//import java.util.StringTokenizer;

SOAP binding Codec that can handle MTOM, SwA, and SOAP messages encoded using XML or Fast Infoset. 
 This is used when we need to determine the encoding from what we received (for decoding) and from configuration and Message contents (for encoding) 

TODO: Split this Codec into two, one that supports FI and one that does not.
Then further split the FI Codec into two, one for client and one for
server. This will simplify the logic and make it easier to understand/maintain.
Author:
Vivek Pandey, Kohsuke Kawaguchi/**
 * SOAP binding {@link Codec} that can handle MTOM, SwA, and SOAP messages
 * encoded using XML or Fast Infoset.
 *
 * <p>
 * This is used when we need to determine the encoding from what we received (for decoding)
 * and from configuration and {@link Message} contents (for encoding)
 *
 * <p>
 * TODO: Split this Codec into two, one that supports FI and one that does not.
 * Then further split the FI Codec into two, one for client and one for
 * server. This will simplify the logic and make it easier to understand/maintain.
 *
 * @author Vivek Pandey
 * @author Kohsuke Kawaguchi
 */
public class SOAPBindingCodec extends MimeCodec implements com.sun.xml.internal.ws.api.pipe.SOAPBindingCodec {

    public static final String UTF8_ENCODING = "utf-8";
    public static final String DEFAULT_ENCODING = UTF8_ENCODING;


    
True if Fast Infoset functionality has been
configured to be disabled, or the Fast Infoset
runtime is not available.
/**
     * True if Fast Infoset functionality has been
     * configured to be disabled, or the Fast Infoset
     * runtime is not available.
     */
    private boolean isFastInfosetDisabled;

    
True if the Fast Infoset codec should be used for encoding.
/**
     * True if the Fast Infoset codec should be used for encoding.
     */
    private boolean useFastInfosetForEncoding;

    
True if the content negotiation property should
be ignored by the client. This will be used in
the case of Fast Infoset being configured to be
disabled or automatically selected.
/**
     * True if the content negotiation property should
     * be ignored by the client. This will be used in
     * the case of Fast Infoset being configured to be
     * disabled or automatically selected.
     */
    private boolean ignoreContentNegotiationProperty;

    // The XML SOAP codec
    private final StreamSOAPCodec xmlSoapCodec;

    // The Fast Infoset SOAP codec
    private final Codec fiSoapCodec;

    // The XML MTOM codec
    private final MimeCodec xmlMtomCodec;

    // The XML SWA codec
    private final MimeCodec xmlSwaCodec;

    // The Fast Infoset SWA codec
    private final MimeCodec fiSwaCodec;

    
The XML SOAP MIME type
/**
     * The XML SOAP MIME type
     */
    private final String xmlMimeType;

    
The Fast Infoset SOAP MIME type
/**
     * The Fast Infoset SOAP MIME type
     */
    private final String fiMimeType;

    
The Accept header for XML encodings
/**
     * The Accept header for XML encodings
     */
    private final String xmlAccept;

    
The Accept header for Fast Infoset and XML encodings
/**
     * The Accept header for Fast Infoset and XML encodings
     */
    private final String connegXmlAccept;

    public StreamSOAPCodec getXMLCodec() {
        return xmlSoapCodec;
    }

    private ContentTypeImpl setAcceptHeader(Packet p, ContentTypeImpl c) {
        String _accept;
        if (!ignoreContentNegotiationProperty && p.contentNegotiation != ContentNegotiation.none) {
            _accept = connegXmlAccept;
        } else {
            _accept = xmlAccept;
        }
        c.setAcceptHeader(_accept);
        return c;
    }

    public SOAPBindingCodec(WSFeatureList features) {
        this(features, Codecs.createSOAPEnvelopeXmlCodec(features));
    }

    public SOAPBindingCodec(WSFeatureList features, StreamSOAPCodec xmlSoapCodec) {
        super(getSoapVersion(features), features);

        this.xmlSoapCodec = xmlSoapCodec;
        xmlMimeType = xmlSoapCodec.getMimeType();

        xmlMtomCodec = new MtomCodec(version, xmlSoapCodec, features);

        xmlSwaCodec = new SwACodec(version, features, xmlSoapCodec);

        String clientAcceptedContentTypes = xmlSoapCodec.getMimeType() + ", " +
                xmlMtomCodec.getMimeType();

        WebServiceFeature fi = features.get(FastInfosetFeature.class);
        isFastInfosetDisabled = (fi != null && !fi.isEnabled());
        if (!isFastInfosetDisabled) {
            fiSoapCodec = getFICodec(xmlSoapCodec, version);
            if (fiSoapCodec != null) {
                fiMimeType = fiSoapCodec.getMimeType();
                fiSwaCodec = new SwACodec(version, features, fiSoapCodec);
                connegXmlAccept = fiMimeType + ", " + clientAcceptedContentTypes;

                /**
                 * This feature will only be present on the client side.
                 *
                 * Fast Infoset is enabled on the client if the service
                 * explicitly supports Fast Infoset.
                 */
                WebServiceFeature select = features.get(SelectOptimalEncodingFeature.class);
                if (select != null) { // if the client FI feature is set - ignore negotiation property
                    ignoreContentNegotiationProperty = true;
                    if (select.isEnabled()) {
                        // If the client's FI encoding feature is enabled, and server's is not disabled
                        if (fi != null) {  // if server's FI feature also enabled
                            useFastInfosetForEncoding = true;
                        }

                        clientAcceptedContentTypes = connegXmlAccept;
                    } else {  // If client FI feature is disabled
                        isFastInfosetDisabled = true;
                    }
                }
            } else {
                // Fast Infoset could not be loaded by the runtime
                isFastInfosetDisabled = true;
                fiSwaCodec = null;
                fiMimeType = "";
                connegXmlAccept = clientAcceptedContentTypes;
                ignoreContentNegotiationProperty = true;
            }
        } else {
            // Fast Infoset is explicitly not supported by the service
            fiSoapCodec = fiSwaCodec = null;
            fiMimeType = "";
            connegXmlAccept = clientAcceptedContentTypes;
            ignoreContentNegotiationProperty = true;
        }

        xmlAccept = clientAcceptedContentTypes;

        if(getSoapVersion(features) == null)
            throw new WebServiceException("Expecting a SOAP binding but found ");
    }

    public String getMimeType() {
        return null;
    }

    public ContentType getStaticContentType(Packet packet) {
        ContentType toAdapt = getEncoder(packet).getStaticContentType(packet);
        return setAcceptHeader(packet, (ContentTypeImpl)toAdapt);
    }

    public ContentType encode(Packet packet, OutputStream out) throws IOException {
       preEncode(packet);
       ContentType ct = getEncoder(packet).encode(packet, out);
       ct = setAcceptHeader(packet, (ContentTypeImpl)ct);
       postEncode();
       return ct;
    }

    public ContentType encode(Packet packet, WritableByteChannel buffer) {
        preEncode(packet);
        ContentType ct = getEncoder(packet).encode(packet, buffer);
        ct = setAcceptHeader(packet, (ContentTypeImpl)ct);
        postEncode();
        return ct;
    }

    
Should be called before encode().
Set the state so that such state is used by encode process.
/**
     * Should be called before encode().
     * Set the state so that such state is used by encode process.
     */
    private void preEncode(Packet p) {
    }

    
Should be called after encode()
Reset the encoding state.
/**
     * Should be called after encode()
     * Reset the encoding state.
     */
    private void postEncode() {
    }

    
Should be called before decode().
Set the state so that such state is used by decode().
/**
     * Should be called before decode().
     * Set the state so that such state is used by decode().
     */
    private void preDecode(Packet p) {
        if (p.contentNegotiation == null)
            useFastInfosetForEncoding = false;
    }

    
Should be called after decode().
Set the state so that such state is used by encode().
/**
     * Should be called after decode().
     * Set the state so that such state is used by encode().
     */
    private void postDecode(Packet p) {
        p.setFastInfosetDisabled(isFastInfosetDisabled);
        if(features.isEnabled(MTOMFeature.class)) p.checkMtomAcceptable();
//            p.setMtomAcceptable( isMtomAcceptable(p.acceptableMimeTypes) );
        MTOMFeature mtomFeature = features.get(MTOMFeature.class);
        if (mtomFeature != null) {
            p.setMtomFeature(mtomFeature);
        }
        if (!useFastInfosetForEncoding) {
            useFastInfosetForEncoding = p.getFastInfosetAcceptable(fiMimeType);
//          useFastInfosetForEncoding = isFastInfosetAcceptable(p.acceptableMimeTypes);
        }
    }

    public void decode(InputStream in, String contentType, Packet packet) throws IOException {
        if (contentType == null) {
            contentType = xmlMimeType;
        }
        packet.setContentType(new ContentTypeImpl(contentType));
        preDecode(packet);
        try {
            if(isMultipartRelated(contentType))
                // parse the multipart portion and then decide whether it's MTOM or SwA
                super.decode(in, contentType, packet);
            else if(isFastInfoset(contentType)) {
                if (!ignoreContentNegotiationProperty && packet.contentNegotiation == ContentNegotiation.none)
                    throw noFastInfosetForDecoding();

                useFastInfosetForEncoding = true;
                fiSoapCodec.decode(in, contentType, packet);
            } else
                xmlSoapCodec.decode(in, contentType, packet);
        } catch(RuntimeException we) {
            if (we instanceof ExceptionHasMessage || we instanceof UnsupportedMediaException) {
                throw we;
            } else {
                throw new MessageCreationException(version, we);
            }
        }
        postDecode(packet);
    }

    public void decode(ReadableByteChannel in, String contentType, Packet packet) {
        if (contentType == null) {
            throw new UnsupportedMediaException();
        }

        preDecode(packet);
        try {
            if(isMultipartRelated(contentType))
                super.decode(in, contentType, packet);
            else if(isFastInfoset(contentType)) {
                if (packet.contentNegotiation == ContentNegotiation.none)
                    throw noFastInfosetForDecoding();

                useFastInfosetForEncoding = true;
                fiSoapCodec.decode(in, contentType, packet);
            } else
                xmlSoapCodec.decode(in, contentType, packet);
        } catch(RuntimeException we) {
            if (we instanceof ExceptionHasMessage || we instanceof UnsupportedMediaException) {
                throw we;
            } else {
                throw new MessageCreationException(version, we);
            }
        }
        postDecode(packet);
    }

    public SOAPBindingCodec copy() {
        return new SOAPBindingCodec(features, (StreamSOAPCodec)xmlSoapCodec.copy());
    }

    @Override
    protected void decode(MimeMultipartParser mpp, Packet packet) throws IOException {
        // is this SwA or XOP?
        final String rootContentType = mpp.getRootPart().getContentType();
        boolean isMTOM = isApplicationXopXml(rootContentType);
        packet.setMtomRequest(isMTOM);
        if(isMTOM) {
            xmlMtomCodec.decode(mpp,packet);
        } else if (isFastInfoset(rootContentType)) {
            if (packet.contentNegotiation == ContentNegotiation.none)
                throw noFastInfosetForDecoding();

            useFastInfosetForEncoding = true;
            fiSwaCodec.decode(mpp,packet);
        } else if (isXml(rootContentType))
            xmlSwaCodec.decode(mpp,packet);
        else {
            // TODO localize exception
            throw new IOException("");
        }
//        checkDuplicateKnownHeaders(packet);
    }

    private boolean isMultipartRelated(String contentType) {
        return compareStrings(contentType, MimeCodec.MULTIPART_RELATED_MIME_TYPE);
    }

    private boolean isApplicationXopXml(String contentType) {
        return compareStrings(contentType, MtomCodec.XOP_XML_MIME_TYPE);
    }

    private boolean isXml(String contentType) {
        return compareStrings(contentType, xmlMimeType);
    }

    private boolean isFastInfoset(String contentType) {
        if (isFastInfosetDisabled) return false;

        return compareStrings(contentType, fiMimeType);
    }

    private boolean compareStrings(String a, String b) {
        return a.length() >= b.length() &&
                b.equalsIgnoreCase(
                a.substring(0,
                b.length()));
    }

//    private boolean isFastInfosetAcceptable(String accept) {
//        if (accept == null || isFastInfosetDisabled) return false;
//
//        StringTokenizer st = new StringTokenizer(accept, ",");
//        while (st.hasMoreTokens()) {
//            final String token = st.nextToken().trim();
//            if (token.equalsIgnoreCase(fiMimeType)) {
//                return true;
//            }
//        }
//        return false;
//    }

    /*
     * Just check if the Accept header contains application/xop+xml,
     * no need to worry about q values.
     */
//    private boolean isMtomAcceptable(String accept) {
//        if (accept == null || isFastInfosetDisabled) return false;
//        StringTokenizer st = new StringTokenizer(accept, ",");
//        while (st.hasMoreTokens()) {
//            final String token = st.nextToken().trim();
//            if (token.toLowerCase().contains(MtomCodec.XOP_XML_MIME_TYPE)) {
//                return true;
//            }
//        }
//        return false;
//    }

    
Determines the encoding codec.
/**
     * Determines the encoding codec.
     */
    private Codec getEncoder(Packet p) {
        /**
         * The following logic is only for outbound packets
         * to be encoded by a client.
         * For a server the p.contentNegotiation == null.
         */
        if (!ignoreContentNegotiationProperty) {
            if (p.contentNegotiation == ContentNegotiation.none) {
                // The client may have changed the negotiation property from
                // pessismistic to none between invocations
                useFastInfosetForEncoding = false;
            } else if (p.contentNegotiation == ContentNegotiation.optimistic) {
                // Always encode using Fast Infoset if in optimisitic mode
                useFastInfosetForEncoding = true;
            }
        }

        // Override the MTOM binding for now
        // Note: Using FI with MTOM does not make sense
        if (useFastInfosetForEncoding) {
            final Message m = p.getMessage();
            if(m==null || m.getAttachments().isEmpty() || features.isEnabled(MTOMFeature.class))
                return fiSoapCodec;
            else
                return fiSwaCodec;
        }

        //If the packet does not have a binding, explicitly set the MTOMFeature
        //on the packet so that it has a way to determine whether to use MTOM
        if (p.getBinding() == null) {
            if (features != null) {
                p.setMtomFeature(features.get(MTOMFeature.class));
            }
        }

        if (p.shouldUseMtom()) {
            return xmlMtomCodec;
        }

        Message m = p.getMessage();
        if(m==null || m.getAttachments().isEmpty())
            return xmlSoapCodec;
        else
            return xmlSwaCodec;
    }

    private RuntimeException noFastInfosetForDecoding() {
        return new RuntimeException(StreamingMessages.FASTINFOSET_DECODING_NOT_ACCEPTED());
    }

    
Obtain an FI SOAP codec instance using reflection.
/**
     * Obtain an FI SOAP codec instance using reflection.
     */
    private static Codec getFICodec(StreamSOAPCodec soapCodec, SOAPVersion version) {
        try {
            Class c = Class.forName("com.sun.xml.internal.ws.encoding.fastinfoset.FastInfosetStreamSOAPCodec");
            Method m = c.getMethod("create", StreamSOAPCodec.class, SOAPVersion.class);
            return (Codec)m.invoke(null, soapCodec, version);
        } catch (Exception e) {
            // TODO Log that FI cannot be loaded
            return null;
        }
    }
}