/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
 * or http://forgerock.org/license/CDDLv1.0.html.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at legal-notices/CDDLv1_0.txt.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information:
 *      Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 *
 *      Copyright 2010 Sun Microsystems, Inc.
 *      Portions copyright 2013 ForgeRock AS
 */

package com.forgerock.opendj.ldap.extensions;

import java.io.IOException;

import org.forgerock.i18n.LocalizableMessage;
import org.forgerock.opendj.io.ASN1;
import org.forgerock.opendj.io.ASN1Reader;
import org.forgerock.opendj.ldap.ByteString;
import org.forgerock.opendj.ldap.DecodeException;
import org.forgerock.opendj.ldap.DecodeOptions;
import org.forgerock.opendj.ldap.ResultCode;
import org.forgerock.opendj.ldap.controls.Control;
import org.forgerock.opendj.ldap.requests.AbstractExtendedRequest;
import org.forgerock.opendj.ldap.requests.ExtendedRequest;
import org.forgerock.opendj.ldap.requests.ExtendedRequestDecoder;
import org.forgerock.opendj.ldap.responses.AbstractExtendedResultDecoder;
import org.forgerock.opendj.ldap.responses.ExtendedResult;
import org.forgerock.opendj.ldap.responses.ExtendedResultDecoder;

/**
 * Get connection ID extended request. This operation can be used to retrieve
 * the client connection ID.
 *
 * @see GetConnectionIDExtendedResult
 */
public final class GetConnectionIDExtendedRequest extends
        AbstractExtendedRequest<GetConnectionIDExtendedRequest, GetConnectionIDExtendedResult> {
    private static final class RequestDecoder implements
            ExtendedRequestDecoder<GetConnectionIDExtendedRequest, GetConnectionIDExtendedResult> {

        public GetConnectionIDExtendedRequest decodeExtendedRequest(
                final ExtendedRequest<?> request, final DecodeOptions options)
                throws DecodeException {
            // TODO: Check the OID and that the value is not present.
            final GetConnectionIDExtendedRequest newRequest = new GetConnectionIDExtendedRequest();
            for (final Control control : request.getControls()) {
                newRequest.addControl(control);
            }
            return newRequest;

        }
    }

    private static final class ResultDecoder extends
            AbstractExtendedResultDecoder<GetConnectionIDExtendedResult> {
        /**
         * {@inheritDoc}
         */
        public GetConnectionIDExtendedResult newExtendedErrorResult(final ResultCode resultCode,
                final String matchedDN, final String diagnosticMessage) {
            if (!resultCode.isExceptional()) {
                // A successful response must contain a response name and
                // value.
                throw new IllegalArgumentException("No response name and value for result code "
                        + resultCode.intValue());
            }
            return GetConnectionIDExtendedResult.newResult(resultCode).setMatchedDN(matchedDN)
                    .setDiagnosticMessage(diagnosticMessage);
        }

        public GetConnectionIDExtendedResult decodeExtendedResult(final ExtendedResult result,
                final DecodeOptions options) throws DecodeException {
            if (result instanceof GetConnectionIDExtendedResult) {
                return (GetConnectionIDExtendedResult) result;
            } else {
                final ResultCode resultCode = result.getResultCode();
                final GetConnectionIDExtendedResult newResult =
                        GetConnectionIDExtendedResult.newResult(resultCode).setMatchedDN(
                                result.getMatchedDN()).setDiagnosticMessage(
                                result.getDiagnosticMessage());

                final ByteString responseValue = result.getValue();
                if (!resultCode.isExceptional() && responseValue == null) {
                    throw DecodeException.error(LocalizableMessage.raw("Empty response value"));
                }
                if (responseValue != null) {
                    try {
                        final ASN1Reader reader = ASN1.getReader(responseValue);
                        newResult.setConnectionID((int) reader.readInteger());
                    } catch (final IOException e) {
                        throw DecodeException.error(LocalizableMessage
                                .raw("Error decoding response value"), e);
                    }
                }
                for (final Control control : result.getControls()) {
                    newResult.addControl(control);
                }
                return newResult;
            }
        }
    }

    /**
     * The OID for the extended operation that can be used to get the client
     * connection ID. It will be both the request and response OID.
     */
    public static final String OID = "1.3.6.1.4.1.26027.1.6.2";

    // Singleton.
    private static final GetConnectionIDExtendedRequest INSTANCE =
            new GetConnectionIDExtendedRequest();

    /**
     * A decoder which can be used to decode get connection ID extended
     * operation requests.
     */
    public static final RequestDecoder REQUEST_DECODER = new RequestDecoder();

    // No need to expose this.
    private static final ResultDecoder RESULT_DECODER = new ResultDecoder();

    /**
     * Creates a new get connection ID extended request.
     *
     * @return The new get connection ID extended request.
     */
    public static GetConnectionIDExtendedRequest newRequest() {
        return INSTANCE;
    }

    // Prevent instantiation.
    private GetConnectionIDExtendedRequest() {
        // Nothing to do.
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getOID() {
        return OID;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public ExtendedResultDecoder<GetConnectionIDExtendedResult> getResultDecoder() {
        return RESULT_DECODER;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public ByteString getValue() {
        return null;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean hasValue() {
        return false;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String toString() {
        final StringBuilder builder = new StringBuilder();
        builder.append("GetConnectionIDExtendedRequest(requestName=");
        builder.append(getOID());
        builder.append(", controls=");
        builder.append(getControls());
        builder.append(")");
        return builder.toString();
    }
}