/*
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.qpid.server.protocol.v0_8.output;

import org.apache.qpid.AMQException;
import org.apache.qpid.framing.AMQBody;
import org.apache.qpid.framing.AMQDataBlock;
import org.apache.qpid.framing.AMQFrame;
import org.apache.qpid.framing.AMQMethodBody;
import org.apache.qpid.framing.AMQShortString;
import org.apache.qpid.framing.BasicCancelOkBody;
import org.apache.qpid.framing.BasicGetOkBody;
import org.apache.qpid.framing.BasicReturnBody;
import org.apache.qpid.framing.ContentHeaderBody;
import org.apache.qpid.framing.MethodRegistry;
import org.apache.qpid.framing.abstraction.MessagePublishInfo;
import org.apache.qpid.protocol.AMQVersionAwareProtocolSession;
import org.apache.qpid.server.message.ServerMessage;
import org.apache.qpid.server.plugin.MessageConverter;
import org.apache.qpid.server.protocol.MessageConverterRegistry;
import org.apache.qpid.server.protocol.v0_8.AMQMessage;
import org.apache.qpid.server.message.MessageContentSource;
import org.apache.qpid.server.protocol.v0_8.AMQProtocolSession;
import org.apache.qpid.server.queue.QueueEntry;

import java.io.DataOutput;
import java.io.IOException;
import java.nio.ByteBuffer;

class ProtocolOutputConverterImpl implements ProtocolOutputConverter
{
    private static final int BASIC_CLASS_ID = 60;

    private final MethodRegistry _methodRegistry;
    private final AMQProtocolSession _protocolSession;

    ProtocolOutputConverterImpl(AMQProtocolSession session, MethodRegistry methodRegistry)
    {
        _protocolSession = session;
        _methodRegistry = methodRegistry;
    }


    public AMQProtocolSession getProtocolSession()
    {
        return _protocolSession;
    }

    public void writeDeliver(QueueEntry entry, int channelId, long deliveryTag, AMQShortString consumerTag)
            throws AMQException
    {
        AMQMessage msg = convertToAMQMessage(entry);
        AMQBody deliverBody = createEncodedDeliverBody(msg, entry.isRedelivered(), deliveryTag, consumerTag);
        writeMessageDelivery(msg, channelId, deliverBody);
    }

    private AMQMessage convertToAMQMessage(QueueEntry entry)
    {
        ServerMessage serverMessage = entry.getMessage();
        if(serverMessage instanceof AMQMessage)
        {
            return (AMQMessage) serverMessage;
        }
        else
        {
            return getMessageConverter(serverMessage).convert(serverMessage, entry.getQueue().getVirtualHost());
        }
    }

    private <M extends ServerMessage> MessageConverter<M, AMQMessage> getMessageConverter(M message)
    {
        Class<M> clazz = (Class<M>) message.getClass();
        return MessageConverterRegistry.getConverter(clazz, AMQMessage.class);
    }

    private void writeMessageDelivery(AMQMessage message, int channelId, AMQBody deliverBody)
            throws AMQException
    {
        writeMessageDelivery(message, message.getContentHeaderBody(), channelId, deliverBody);
    }

    private void writeMessageDelivery(MessageContentSource message, ContentHeaderBody contentHeaderBody, int channelId, AMQBody deliverBody)
            throws AMQException
    {


        int bodySize = (int) message.getSize();

        if(bodySize == 0)
        {
            SmallCompositeAMQBodyBlock compositeBlock = new SmallCompositeAMQBodyBlock(channelId, deliverBody,
                                                                             contentHeaderBody);

            writeFrame(compositeBlock);
        }
        else
        {
            int maxBodySize = (int) getProtocolSession().getMaxFrameSize() - AMQFrame.getFrameOverhead();


            int capacity = bodySize > maxBodySize ? maxBodySize : bodySize;

            int writtenSize = capacity;

            AMQBody firstContentBody = new MessageContentSourceBody(message,0,capacity);

            CompositeAMQBodyBlock
                    compositeBlock = new CompositeAMQBodyBlock(channelId, deliverBody, contentHeaderBody, firstContentBody);
            writeFrame(compositeBlock);

            while(writtenSize < bodySize)
            {
                capacity = bodySize - writtenSize > maxBodySize ? maxBodySize : bodySize - writtenSize;
                MessageContentSourceBody body = new MessageContentSourceBody(message, writtenSize, capacity);
                writtenSize += capacity;

                writeFrame(new AMQFrame(channelId, body));
            }
        }
    }

    private class MessageContentSourceBody implements AMQBody
    {
        public static final byte TYPE = 3;
        private int _length;
        private MessageContentSource _message;
        private int _offset;

        public MessageContentSourceBody(MessageContentSource message, int offset, int length)
        {
            _message = message;
            _offset = offset;
            _length = length;
        }

        public byte getFrameType()
        {
            return TYPE;
        }

        public int getSize()
        {
            return _length;
        }

        public void writePayload(DataOutput buffer) throws IOException
        {
            ByteBuffer buf = _message.getContent(_offset, _length);

            if(buf.hasArray())
            {
                buffer.write(buf.array(), buf.arrayOffset()+buf.position(), buf.remaining());
            }
            else
            {

                byte[] data = new byte[_length];

                buf.get(data);

                buffer.write(data);
            }
        }

        public void handle(int channelId, AMQVersionAwareProtocolSession amqProtocolSession) throws AMQException
        {
            throw new UnsupportedOperationException();
        }
    }

    public void writeGetOk(QueueEntry entry, int channelId, long deliveryTag, int queueSize) throws AMQException
    {
        AMQBody deliver = createEncodedGetOkBody(entry, deliveryTag, queueSize);
        writeMessageDelivery(convertToAMQMessage(entry), channelId, deliver);
    }


    private AMQBody createEncodedDeliverBody(AMQMessage message,
                                             boolean isRedelivered,
                                             final long deliveryTag,
                                             final AMQShortString consumerTag)
            throws AMQException
    {

        final AMQShortString exchangeName;
        final AMQShortString routingKey;

        final MessagePublishInfo pb = message.getMessagePublishInfo();
        exchangeName = pb.getExchange();
        routingKey = pb.getRoutingKey();

        final AMQBody returnBlock = new EncodedDeliveryBody(deliveryTag, routingKey, exchangeName, consumerTag, isRedelivered);
        return returnBlock;
    }

    private class EncodedDeliveryBody implements AMQBody
    {
        private final long _deliveryTag;
        private final AMQShortString _routingKey;
        private final AMQShortString _exchangeName;
        private final AMQShortString _consumerTag;
        private final boolean _isRedelivered;
        private AMQBody _underlyingBody;

        private EncodedDeliveryBody(long deliveryTag, AMQShortString routingKey, AMQShortString exchangeName, AMQShortString consumerTag, boolean isRedelivered)
        {
            _deliveryTag = deliveryTag;
            _routingKey = routingKey;
            _exchangeName = exchangeName;
            _consumerTag = consumerTag;
            _isRedelivered = isRedelivered;
        }

        public AMQBody createAMQBody()
        {
            return _methodRegistry.createBasicDeliverBody(_consumerTag,
                                                          _deliveryTag,
                                                          _isRedelivered,
                                                          _exchangeName,
                                                          _routingKey);
        }

        public byte getFrameType()
        {
            return AMQMethodBody.TYPE;
        }

        public int getSize()
        {
            if(_underlyingBody == null)
            {
                _underlyingBody = createAMQBody();
            }
            return _underlyingBody.getSize();
        }

        public void writePayload(DataOutput buffer) throws IOException
        {
            if(_underlyingBody == null)
            {
                _underlyingBody = createAMQBody();
            }
            _underlyingBody.writePayload(buffer);
        }

        public void handle(final int channelId, final AMQVersionAwareProtocolSession amqMinaProtocolSession)
            throws AMQException
        {
            throw new AMQException("This block should never be dispatched!");
        }

        @Override
        public String toString()
        {
            return "[" + getClass().getSimpleName() + " underlyingBody: " + String.valueOf(_underlyingBody) + "]";
        }
    }

    private AMQBody createEncodedGetOkBody(QueueEntry entry, long deliveryTag, int queueSize)
            throws AMQException
    {
        final AMQShortString exchangeName;
        final AMQShortString routingKey;

        final AMQMessage message = convertToAMQMessage(entry);
        final MessagePublishInfo pb = message.getMessagePublishInfo();
        exchangeName = pb.getExchange();
        routingKey = pb.getRoutingKey();

        final boolean isRedelivered = entry.isRedelivered();

        BasicGetOkBody getOkBody =
                _methodRegistry.createBasicGetOkBody(deliveryTag,
                                                    isRedelivered,
                                                    exchangeName,
                                                    routingKey,
                                                    queueSize);

        return getOkBody;
    }

    public byte getProtocolMinorVersion()
    {
        return _protocolSession.getProtocolMinorVersion();
    }

    public byte getProtocolMajorVersion()
    {
        return getProtocolSession().getProtocolMajorVersion();
    }

    private AMQBody createEncodedReturnFrame(MessagePublishInfo messagePublishInfo,
                                             int replyCode,
                                             AMQShortString replyText) throws AMQException
    {

        BasicReturnBody basicReturnBody =
                _methodRegistry.createBasicReturnBody(replyCode,
                                                     replyText,
                                                     messagePublishInfo.getExchange(),
                                                     messagePublishInfo.getRoutingKey());


        return basicReturnBody;
    }

    public void writeReturn(MessagePublishInfo messagePublishInfo, ContentHeaderBody header, MessageContentSource message, int channelId, int replyCode, AMQShortString replyText)
            throws AMQException
    {

        AMQBody returnFrame = createEncodedReturnFrame(messagePublishInfo, replyCode, replyText);

        writeMessageDelivery(message, header, channelId, returnFrame);
    }


    public void writeFrame(AMQDataBlock block)
    {
        getProtocolSession().writeFrame(block);
    }


    public void confirmConsumerAutoClose(int channelId, AMQShortString consumerTag)
    {

        BasicCancelOkBody basicCancelOkBody = _methodRegistry.createBasicCancelOkBody(consumerTag);
        writeFrame(basicCancelOkBody.generateFrame(channelId));

    }


    public static final class CompositeAMQBodyBlock extends AMQDataBlock
    {
        public static final int OVERHEAD = 3 * AMQFrame.getFrameOverhead();

        private final AMQBody _methodBody;
        private final AMQBody _headerBody;
        private final AMQBody _contentBody;
        private final int _channel;


        public CompositeAMQBodyBlock(int channel, AMQBody methodBody, AMQBody headerBody, AMQBody contentBody)
        {
            _channel = channel;
            _methodBody = methodBody;
            _headerBody = headerBody;
            _contentBody = contentBody;
        }

        public long getSize()
        {
            return OVERHEAD + _methodBody.getSize() + _headerBody.getSize() + _contentBody.getSize();
        }

        public void writePayload(DataOutput buffer) throws IOException
        {
            AMQFrame.writeFrames(buffer, _channel, _methodBody, _headerBody, _contentBody);
        }

        @Override
        public String toString()
        {
            StringBuilder builder = new StringBuilder();
            builder.append("[").append(getClass().getSimpleName())
                .append(" methodBody=").append(_methodBody)
                .append(", headerBody=").append(_headerBody)
                .append(", contentBody=").append(_contentBody)
                .append(", channel=").append(_channel).append("]");
            return builder.toString();
        }

    }

    public static final class SmallCompositeAMQBodyBlock extends AMQDataBlock
    {
        public static final int OVERHEAD = 2 * AMQFrame.getFrameOverhead();

        private final AMQBody _methodBody;
        private final AMQBody _headerBody;
        private final int _channel;


        public SmallCompositeAMQBodyBlock(int channel, AMQBody methodBody, AMQBody headerBody)
        {
            _channel = channel;
            _methodBody = methodBody;
            _headerBody = headerBody;

        }

        public long getSize()
        {
            return OVERHEAD + _methodBody.getSize() + _headerBody.getSize() ;
        }

        public void writePayload(DataOutput buffer) throws IOException
        {
            AMQFrame.writeFrames(buffer, _channel, _methodBody, _headerBody);
        }

        @Override
        public String toString()
        {
            StringBuilder builder = new StringBuilder();
            builder.append(getClass().getSimpleName())
                .append("methodBody=").append(_methodBody)
                .append(", headerBody=").append(_headerBody)
                .append(", channel=").append(_channel).append("]");
            return builder.toString();
        }
    }

}
