/**
 * @note This file is named NetworkDatabase.h instead of NetDb.h to avoid
 *  a possible nameclash with a file included by boost on case insensitive
 *  filesystems.
 */
#ifndef NETDB_H__
#define NETDB_H__

#include <inttypes.h>
#include <set>
#include <map>
#include <list>
#include <string>
#include <thread>
#include <mutex>
#include <boost/filesystem.hpp>
#include "util/Queue.h"
#include "I2NPProtocol.h"
#include "RouterInfo.h"
#include "LeaseSet.h"
#include "tunnel/Tunnel.h"
#include "tunnel/TunnelPool.h"
#include "Reseed.h"
#include "NetDbRequests.h"

namespace i2p
{
namespace data
{       
    
    class NetDb
    {
        public:

            NetDb ();
            ~NetDb ();

            void Start ();
            void Stop ();
            
            void AddRouterInfo (const uint8_t * buf, int len);
            void AddRouterInfo (const IdentHash& ident, const uint8_t * buf, int len);
            void AddLeaseSet (const IdentHash& ident, const uint8_t * buf, int len, std::shared_ptr<i2p::tunnel::InboundTunnel> from);
            std::shared_ptr<RouterInfo> FindRouter (const IdentHash& ident) const;
            std::shared_ptr<LeaseSet> FindLeaseSet (const IdentHash& destination) const;

            void RequestDestination (const IdentHash& destination, RequestedDestination::RequestComplete requestComplete = nullptr);            
            
            void HandleDatabaseStoreMsg (std::shared_ptr<const I2NPMessage> msg);
            void HandleDatabaseSearchReplyMsg (std::shared_ptr<const I2NPMessage> msg);
            void HandleDatabaseLookupMsg (std::shared_ptr<const I2NPMessage> msg);          

            std::shared_ptr<const RouterInfo> GetRandomRouter () const;
            std::shared_ptr<const RouterInfo> GetRandomRouter (std::shared_ptr<const RouterInfo> compatibleWith) const;
            std::shared_ptr<const RouterInfo> GetHighBandwidthRandomRouter (std::shared_ptr<const RouterInfo> compatibleWith) const;
            std::shared_ptr<const RouterInfo> GetRandomPeerTestRouter () const;
            std::shared_ptr<const RouterInfo> GetRandomIntroducer () const;
            std::shared_ptr<const RouterInfo> GetClosestFloodfill (const IdentHash& destination, const std::set<IdentHash>& excluded) const;
            std::vector<IdentHash> GetClosestFloodfills (const IdentHash& destination, size_t num,
                std::set<IdentHash>& excluded) const;
            std::shared_ptr<const RouterInfo> GetClosestNonFloodfill (const IdentHash& destination, const std::set<IdentHash>& excluded) const;
            void SetUnreachable (const IdentHash& ident, bool unreachable);         

            void PostI2NPMsg (std::shared_ptr<const I2NPMessage> msg);

            void Reseed ();

            // for web interface
            int GetNumRouters () const { return m_RouterInfos.size (); };
            int GetNumFloodfills () const { return m_Floodfills.size (); };
            int GetNumLeaseSets () const { return m_LeaseSets.size (); };
            
        private:

            bool CreateNetDb(boost::filesystem::path directory);
            void Load ();
            void SaveUpdated ();
            void Run (); // exploratory thread
            void Explore (int numDestinations); 
            void Publish ();
            void ManageLeaseSets ();
            void ManageRequests ();

            template<typename Filter>
            std::shared_ptr<const RouterInfo> GetRandomRouter (Filter filter) const;    
        
        private:

            std::map<IdentHash, std::shared_ptr<LeaseSet> > m_LeaseSets;
            mutable std::mutex m_RouterInfosMutex;
            std::map<IdentHash, std::shared_ptr<RouterInfo> > m_RouterInfos;
            mutable std::mutex m_FloodfillsMutex;
            std::list<std::shared_ptr<RouterInfo> > m_Floodfills;
            
            bool m_IsRunning;
            std::thread * m_Thread; 
            i2p::util::Queue<std::shared_ptr<const I2NPMessage> > m_Queue; // of I2NPDatabaseStoreMsg

            Reseeder * m_Reseeder;

            friend class NetDbRequests; 
            NetDbRequests m_Requests;

            static const char m_NetDbPath[];
    };

    extern NetDb netdb;
}
}

#endif