// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2012 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#ifndef __cplusplus
# error This header can only be compiled as C++.
#endif

#ifndef __INCLUDED_PROTOCOL_H__
#define __INCLUDED_PROTOCOL_H__

#include "serialize.h"
#include "netbase.h"
#include <string>
#include "uint256.h"

extern bool fTestNet;
static inline unsigned short GetDefaultPort(const bool testnet = fTestNet)
{
    return testnet ? 25714 : 32001;
}


extern unsigned char pchMessageStart[4];

/** Message header.
 * (4) message start.
 * (12) command.
 * (4) size.
 * (4) checksum.
 */
class CMessageHeader
{
    public:
        CMessageHeader();
        CMessageHeader(const char* pszCommand, unsigned int nMessageSizeIn);

        std::string GetCommand() const;
        bool IsValid() const;

        IMPLEMENT_SERIALIZE
            (
             READWRITE(FLATDATA(pchMessageStart));
             READWRITE(FLATDATA(pchCommand));
             READWRITE(nMessageSize);
             READWRITE(nChecksum);
            )

    // TODO: make private (improves encapsulation)
    public:
        enum {
            MESSAGE_START_SIZE=sizeof(::pchMessageStart),
            COMMAND_SIZE=12,
            MESSAGE_SIZE_SIZE=sizeof(int),
            CHECKSUM_SIZE=sizeof(int),

            MESSAGE_SIZE_OFFSET=MESSAGE_START_SIZE+COMMAND_SIZE,
            CHECKSUM_OFFSET=MESSAGE_SIZE_OFFSET+MESSAGE_SIZE_SIZE,
            HEADER_SIZE=MESSAGE_START_SIZE+COMMAND_SIZE+MESSAGE_SIZE_SIZE+CHECKSUM_SIZE
        };
        char pchMessageStart[MESSAGE_START_SIZE];
        char pchCommand[COMMAND_SIZE];
        unsigned int nMessageSize;
        unsigned int nChecksum;
};

/**
 * Bitcoin protocol message types. When adding new message types, don't forget
 * to update allNetMessageTypes in protocol.cpp.
 */
namespace NetMsgType {

/**
 * The version message provides information about the transmitting node to the
 * receiving node at the beginning of a connection.
 * @see https://bitcoin.org/en/developer-reference#version
 */
extern const char *VERSION;
/**
 * The verack message acknowledges a previously-received version message,
 * informing the connecting node that it can begin to send other messages.
 * @see https://bitcoin.org/en/developer-reference#verack
 */
extern const char *VERACK;
/**
 * The addr (IP address) message relays connection information for peers on the
 * network.
 * @see https://bitcoin.org/en/developer-reference#addr
 */
extern const char *ADDR;
/**
 * The inv message (inventory message) transmits one or more inventories of
 * objects known to the transmitting peer.
 * @see https://bitcoin.org/en/developer-reference#inv
 */
extern const char *INV;
/**
 * The getdata message requests one or more data objects from another node.
 * @see https://bitcoin.org/en/developer-reference#getdata
 */
extern const char *GETDATA;
/**
 * The merkleblock message is a reply to a getdata message which requested a
 * block using the inventory type MSG_MERKLEBLOCK.
 * @since protocol version 70001 as described by BIP37.
 * @see https://bitcoin.org/en/developer-reference#merkleblock
 */
extern const char *MERKLEBLOCK;
/**
 * The getblocks message requests an inv message that provides block header
 * hashes starting from a particular point in the block chain.
 * @see https://bitcoin.org/en/developer-reference#getblocks
 */
extern const char *GETBLOCKS;
/**
 * The getheaders message requests a headers message that provides block
 * headers starting from a particular point in the block chain.
 * @since protocol version 31800.
 * @see https://bitcoin.org/en/developer-reference#getheaders
 */
extern const char *GETHEADERS;
/**
 * The tx message transmits a single transaction.
 * @see https://bitcoin.org/en/developer-reference#tx
 */
extern const char *TX;
/**
 * The headers message sends one or more block headers to a node which
 * previously requested certain headers with a getheaders message.
 * @since protocol version 31800.
 * @see https://bitcoin.org/en/developer-reference#headers
 */
extern const char *HEADERS;
/**
 * The block message transmits a single serialized block.
 * @see https://bitcoin.org/en/developer-reference#block
 */
extern const char *BLOCK;
/**
 * The getaddr message requests an addr message from the receiving node,
 * preferably one with lots of IP addresses of other receiving nodes.
 * @see https://bitcoin.org/en/developer-reference#getaddr
 */
extern const char *GETADDR;
/**
 * The mempool message requests the TXIDs of transactions that the receiving
 * node has verified as valid but which have not yet appeared in a block.
 * @since protocol version 60002.
 * @see https://bitcoin.org/en/developer-reference#mempool
 */
extern const char *MEMPOOL;
/**
 * The ping message is sent periodically to help confirm that the receiving
 * peer is still connected.
 * @see https://bitcoin.org/en/developer-reference#ping
 */
extern const char *PING;
/**
 * The pong message replies to a ping message, proving to the pinging node that
 * the ponging node is still alive.
 * @since protocol version 60001 as described by BIP31.
 * @see https://bitcoin.org/en/developer-reference#pong
 */
extern const char *PONG;
/**
 * The alert message warns nodes of problems that may affect them or the rest
 * of the network.
 * @since protocol version 311.
 * @see https://bitcoin.org/en/developer-reference#alert
 */
extern const char *ALERT;
/**
 * The notfound message is a reply to a getdata message which requested an
 * object the receiving node does not have available for relay.
 * @ince protocol version 70001.
 * @see https://bitcoin.org/en/developer-reference#notfound
 */
extern const char *NOTFOUND;
/**
 * The filterload message tells the receiving peer to filter all relayed
 * transactions and requested merkle blocks through the provided filter.
 * @since protocol version 70001 as described by BIP37.
 *   Only available with service bit NODE_BLOOM since protocol version
 *   70011 as described by BIP111.
 * @see https://bitcoin.org/en/developer-reference#filterload
 */
extern const char *FILTERLOAD;
/**
 * The filteradd message tells the receiving peer to add a single element to a
 * previously-set bloom filter, such as a new public key.
 * @since protocol version 70001 as described by BIP37.
 *   Only available with service bit NODE_BLOOM since protocol version
 *   70011 as described by BIP111.
 * @see https://bitcoin.org/en/developer-reference#filteradd
 */
extern const char *FILTERADD;
/**
 * The filterclear message tells the receiving peer to remove a previously-set
 * bloom filter.
 * @since protocol version 70001 as described by BIP37.
 *   Only available with service bit NODE_BLOOM since protocol version
 *   70011 as described by BIP111.
 * @see https://bitcoin.org/en/developer-reference#filterclear
 */
extern const char *FILTERCLEAR;
/**
 * The reject message informs the receiving node that one of its previous
 * messages has been rejected.
 * @since protocol version 70002 as described by BIP61.
 * @see https://bitcoin.org/en/developer-reference#reject
 */
extern const char *REJECT;
/**
 * Indicates that a node prefers to receive new block announcements via a
 * "headers" message rather than an "inv".
 * @since protocol version 70012 as described by BIP130.
 * @see https://bitcoin.org/en/developer-reference#sendheaders
 */
extern const char *SENDHEADERS;

// Neutron message types
// NOTE: do NOT declare non-implmented here, we don't want them to be exposed to the outside
// TODO: add description
extern const char *SPORK;
extern const char *GETSPORKS;
extern const char *MASTERNODEPAYMENTVOTE;
extern const char *MASTERNODEPAYMENTSYNC;
extern const char *DSTX;
extern const char *DSEG;
extern const char *DSEE;
extern const char *DSEEP;
// TODO: add all commands
};

/* Get a vector of all valid message types (see above) */
const std::vector<std::string> &getAllNetMessageTypes();

/** nServices flags */
enum
{
    NODE_NETWORK = (1 << 0),
};

/** A CService with information about it as peer */
class CAddress : public CService
{
    public:
        CAddress();
        explicit CAddress(CService ipIn, uint64_t nServicesIn=NODE_NETWORK);

        void Init();

        IMPLEMENT_SERIALIZE
            (
             CAddress* pthis = const_cast<CAddress*>(this);
             CService* pip = (CService*)pthis;
             if (fRead)
                 pthis->Init();
             if (nType & SER_DISK)
                 READWRITE(nVersion);
             if ((nType & SER_DISK) ||
                 (nVersion >= CADDR_TIME_VERSION && !(nType & SER_GETHASH)))
                 READWRITE(nTime);
             READWRITE(nServices);
             READWRITE(*pip);
            )

        void print() const;

    // TODO: make private (improves encapsulation)
    public:
        uint64_t nServices;

        // disk and network only
        unsigned int nTime;

        // memory only
        int64_t nLastTry;
};

/** inv message data */
class CInv
{
    public:
        CInv();
        CInv(int typeIn, const uint256& hashIn);
        CInv(const std::string& strType, const uint256& hashIn);

        IMPLEMENT_SERIALIZE
        (
            READWRITE(type);
            READWRITE(hash);
        )

        friend bool operator<(const CInv& a, const CInv& b);

        bool IsKnownType() const;
        const char* GetCommand() const;
        std::string ToString() const;
        void print() const;

    // TODO: make private (improves encapsulation)
    public:
        int type;
        uint256 hash;
};

enum
{
    MSG_TX = 1,
    MSG_BLOCK,
    // Nodes may always request a MSG_FILTERED_BLOCK in a getdata, however,
    // MSG_FILTERED_BLOCK should not appear in any invs except as a part of getdata.
    MSG_FILTERED_BLOCK,
    // Neutron message types
    // NOTE: declare non-implmented here, we must keep this enum consistent and backwards compatible
    MSG_SPORK,
    MSG_MASTERNODE_WINNER,
};

#endif // __INCLUDED_PROTOCOL_H__
