/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2011 University of California, Los Angeles
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Author: Ilya Moiseenko <iliamo@cs.ucla.edu>
 */

#ifndef ccnx_content_store_h
#define	ccnx_content_store_h

#include <ns3/system-mutex.h>
#include <list>
#include <string>
#include "hash-helper.h"

using namespace std;

namespace  ns3
{
    
class CsEntry;
typedef list<CsEntry*>::iterator CsLruIterator;
        
//structure for CS entry
struct CsEntry
{
    string contentName;
    int contentSize;
            
    CsLruIterator lruPosition;
};
        
typedef string_key_hash_t<CsEntry>::iterator CsIterator;
typedef string_key_hash_t<CsEntry>::iterator CsRangeIterator;
    
class CcnxContentStore
{
public:
    CcnxContentStore( int max_size=NDN_CONTENT_STORE_SIZE );
    virtual ~CcnxContentStore( );
            
    // Find corresponding CS entry for the given content name
    CsEntry* Lookup( const string prefix );
    //bool isValid( const CsIterator &it ) { return it!=_cs.end(); }
            
    // Add new content to the content store. Old content will be replaced
    void Add( const string contentName, int contentSize );
            
    // Dump content store entries
    void Dump( );
            
protected:
    //move the given CS entry to the head of the list
    void Promote( CsEntry &entry );
            
private:
    int                   m_maxSize; // maximum number of entries in cache
            
    string_key_hash_t<CsEntry>  m_contentStore;     // actual content store
    list<CsEntry*>			  m_LRU;	// LRU index of the content store
    SystemMutex				m_csMutex;   // just to make sure we are not
};
}
#endif