/*
 * Copyright (C) 2009-2010 Big Muscle, http://strongdc.sourceforge.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, see <https://www.gnu.org/licenses/>.
 */

#pragma once

#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 dcpp::intrusive_ptr<Node> Ptr;
        typedef std::map<CID, Node::Ptr> Map;

        Node(const UserPtr& u);
        ~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, const std::string &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;

    };

}
