/*
 *
 * Copyright (c) 2006 The Apache Software Foundation
 *
 * Licensed 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.
 *
 */
#ifndef _QueueRegistry_
#define _QueueRegistry_

#include <map>
#include "qpid/sys/Monitor.h"
#include "qpid/broker/Queue.h"

namespace qpid {
namespace broker {

class SessionHandlerImpl;

/**
 * A registry of queues indexed by queue name.
 *
 * Queues are reference counted using shared_ptr to ensure that they
 * are deleted when and only when they are no longer in use.
 *
 */
class QueueRegistry{
 
  public:
    QueueRegistry(MessageStore* const store = 0);
    ~QueueRegistry();

    /**
     * Declare a queue.
     *
     * @return The queue and a boolean flag which is true if the queue
     * was created by this declare call false if it already existed.
     */
    std::pair<Queue::shared_ptr, bool> declare(const string& name, bool durable = false, u_int32_t autodelete = 0, 
                                               const ConnectionToken* const owner = 0);

    /**
     * Destroy the named queue.
     *
     * Note: if the queue is in use it is not actually destroyed until
     * all shared_ptrs to it are destroyed. During that time it is
     * possible that a new queue with the same name may be
     * created. This should not create any problems as the new and
     * old queues exist independently. The registry has
     * forgotten the old queue so there can be no confusion for
     * subsequent calls to find or declare with the same name.
     *
     */
    void destroy(const string& name);

    /**
     * Find the named queue. Return 0 if not found.
     */
    Queue::shared_ptr find(const string& name);

    /**
     * Generate unique queue name.
     */
    string generateName();

  private:
    typedef std::map<string, Queue::shared_ptr> QueueMap;
    QueueMap queues;
    qpid::sys::Mutex lock;
    int counter;
    MessageStore* const store;
};

    
}
}


#endif