#ifndef QPID_MESSAGING_RECEIVER_H
#define QPID_MESSAGING_RECEIVER_H

/*
 *
 * 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.
 *
 */
#include "qpid/Exception.h"
#include "qpid/client/ClientImportExport.h"
#include "qpid/client/Handle.h"
#include "qpid/sys/Time.h"

namespace qpid {
namespace client {

template <class> class PrivateImplRef;

}

namespace messaging {

class Message;
class MessageListener;
class ReceiverImpl;

/**
 * A pull style interface for message retrieval.
 */
class Receiver : public qpid::client::Handle<ReceiverImpl>
{
  public:
    struct NoMessageAvailable : qpid::Exception {};

    QPID_CLIENT_EXTERN Receiver(ReceiverImpl* impl = 0);
    QPID_CLIENT_EXTERN Receiver(const Receiver&);
    QPID_CLIENT_EXTERN ~Receiver();
    QPID_CLIENT_EXTERN Receiver& operator=(const Receiver&);
    /**
     * Retrieves a message from this receivers local queue, or waits
     * for upto the specified timeout for a message to become
     * available. Returns false if there is no message to give after
     * waiting for the specified timeout.
     */
    QPID_CLIENT_EXTERN bool get(Message& message, qpid::sys::Duration timeout=qpid::sys::TIME_INFINITE);
    /**
     * Retrieves a message from this receivers local queue, or waits
     * for upto the specified timeout for a message to become
     * available. Throws NoMessageAvailable if there is no
     * message to give after waiting for the specified timeout.
     */
    QPID_CLIENT_EXTERN Message get(qpid::sys::Duration timeout=qpid::sys::TIME_INFINITE);
    /**
     * Retrieves a message for this receivers subscription or waits
     * for upto the specified timeout for one to become
     * available. Unlike get() this method will check with the server
     * that there is no message for the subscription this receiver is
     * serving before returning false.
     */
    QPID_CLIENT_EXTERN bool fetch(Message& message, qpid::sys::Duration timeout=qpid::sys::TIME_INFINITE);
    /**
     * Retrieves a message for this receivers subscription or waits
     * for upto the specified timeout for one to become
     * available. Unlike get() this method will check with the server
     * that there is no message for the subscription this receiver is
     * serving before throwing an exception.
     */
    QPID_CLIENT_EXTERN Message fetch(qpid::sys::Duration timeout=qpid::sys::TIME_INFINITE);
    
    /**
     * Enables the message flow for this receiver
     */
    QPID_CLIENT_EXTERN void start();
    /**
     * Stops the message flow for this receiver (without actually
     * cancelling the subscription).
     */
    QPID_CLIENT_EXTERN void stop();
    /**
     * Sets the capacity for the receiver. The capacity determines how
     * many incoming messages can be held in the receiver before being
     * requested by a client via fetch() (or pushed to a listener).
     */
    QPID_CLIENT_EXTERN void setCapacity(uint32_t);

    /**
     * Cancels this receiver
     */
    QPID_CLIENT_EXTERN void cancel();

    /**
     * Set a message listener for receiving messages asynchronously.
     */
    QPID_CLIENT_EXTERN void setListener(MessageListener* listener);
  private:
  friend class qpid::client::PrivateImplRef<Receiver>;
};
}} // namespace qpid::messaging

#endif  /*!QPID_MESSAGING_RECEIVER_H*/