/*
 * Copyright (C) 2009-2010 Big Muscle, http://strongdc.sf.net
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef _KBUCKET_H
#define _KBUCKET_H

#include "Constants.h"

#include "dcpp/CID.h"
#include "dcpp/Client.h"
#include "dcpp/MerkleTree.h"
#include "dcpp/Pointer.h"
#include "dcpp/SimpleXML.h"
#include "dcpp/TimerManager.h"
#include "dcpp/User.h"

namespace dht
{
	struct UDPKey
	{
		string	ip;
		CID		key;
	};

	struct Node :
		public OnlineUser
	{
		typedef boost::intrusive_ptr<Node> Ptr;
		typedef std::map<CID, Node::Ptr> Map;

		Node(const UserPtr& u);
		virtual ~Node() throw();

		uint8_t getType() const { return type; }
		bool isIpVerified() const { return ipVerified; }

		bool isOnline() const { return online; }
		void setOnline(bool _online) { online = _online; }

		void setAlive();
		void setIpVerified(bool verified) { ipVerified = verified; }
		void setTimeout(uint64_t now = GET_TICK());

		CID getUdpKey() const;
		void setUdpKey(const CID& _key);
		const UDPKey& getUDPKey() const { return key; }

	private:

		friend class KBucket;

		UDPKey		key;

		uint64_t	created;
		uint64_t	expires;
		uint8_t		type;
		bool		ipVerified;
		bool		online;	// getUser()->isOnline() returns true when node is online in any hub, we need info when he is online in DHT
	};

	class KBucket
	{
	public:
		KBucket(void);
		~KBucket(void);

		typedef std::deque<Node::Ptr> NodeList;

		/** Creates new (or update existing) node which is NOT added to our routing table */
		Node::Ptr createNode(const UserPtr& u, const string& ip, uint16_t port, bool update, bool isUdpKeyValid);

		/** Adds node to routing table */
		bool insert(const Node::Ptr& node);

		/** Finds "max" closest nodes and stores them to the list */
		void getClosestNodes(const CID& cid, Node::Map& closest, unsigned int max, uint8_t maxType) const;

		/** Return list of all nodes in this bucket */
		const NodeList& getNodes() const { return nodes; }

		/** Removes dead nodes */
		bool checkExpiration(uint64_t currentTime);

		/** Loads existing nodes from disk */
		void loadNodes(SimpleXML& xml);

		/** Save bootstrap nodes to disk */
		void saveNodes(SimpleXML& xml);

	private:

		/** List of nodes in this bucket */
		NodeList nodes;

		/** List of known IPs in this bucket */
		StringSet ipMap;

	};

}

#endif	// _KBUCKET_H
