// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2022 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <protocol.h>

#include <common/system.h>

#include <atomic>

static std::atomic<bool> g_initial_block_download_completed(false);

namespace NetMsgType {
const char* VERSION = "version";
const char* VERACK = "verack";
const char* ADDR = "addr";
const char* ADDRV2 = "addrv2";
const char* SENDADDRV2 = "sendaddrv2";
const char* INV = "inv";
const char* GETDATA = "getdata";
const char* MERKLEBLOCK = "merkleblock";
const char* GETBLOCKS = "getblocks";
const char* GETHEADERS = "getheaders";
const char* TX = "tx";
const char* HEADERS = "headers";
const char* BLOCK = "block";
const char* GETADDR = "getaddr";
const char* MEMPOOL = "mempool";
const char* PING = "ping";
const char* PONG = "pong";
const char* NOTFOUND = "notfound";
const char* FILTERLOAD = "filterload";
const char* FILTERADD = "filteradd";
const char* FILTERCLEAR = "filterclear";
const char* SENDHEADERS = "sendheaders";
const char* FEEFILTER = "feefilter";
const char* SENDCMPCT = "sendcmpct";
const char* CMPCTBLOCK = "cmpctblock";
const char* GETBLOCKTXN = "getblocktxn";
const char* BLOCKTXN = "blocktxn";
const char* GETCFILTERS = "getcfilters";
const char* CFILTER = "cfilter";
const char* GETCFHEADERS = "getcfheaders";
const char* CFHEADERS = "cfheaders";
const char* GETCFCHECKPT = "getcfcheckpt";
const char* CFCHECKPT = "cfcheckpt";
const char* WTXIDRELAY = "wtxidrelay";
const char* SENDTXRCNCL = "sendtxrcncl";
} // namespace NetMsgType

/** All known message types. Keep this in the same order as the list of
 * messages above and in protocol.h.
 */
const static std::vector<std::string> g_all_net_message_types{
    NetMsgType::VERSION,
    NetMsgType::VERACK,
    NetMsgType::ADDR,
    NetMsgType::ADDRV2,
    NetMsgType::SENDADDRV2,
    NetMsgType::INV,
    NetMsgType::GETDATA,
    NetMsgType::MERKLEBLOCK,
    NetMsgType::GETBLOCKS,
    NetMsgType::GETHEADERS,
    NetMsgType::TX,
    NetMsgType::HEADERS,
    NetMsgType::BLOCK,
    NetMsgType::GETADDR,
    NetMsgType::MEMPOOL,
    NetMsgType::PING,
    NetMsgType::PONG,
    NetMsgType::NOTFOUND,
    NetMsgType::FILTERLOAD,
    NetMsgType::FILTERADD,
    NetMsgType::FILTERCLEAR,
    NetMsgType::SENDHEADERS,
    NetMsgType::FEEFILTER,
    NetMsgType::SENDCMPCT,
    NetMsgType::CMPCTBLOCK,
    NetMsgType::GETBLOCKTXN,
    NetMsgType::BLOCKTXN,
    NetMsgType::GETCFILTERS,
    NetMsgType::CFILTER,
    NetMsgType::GETCFHEADERS,
    NetMsgType::CFHEADERS,
    NetMsgType::GETCFCHECKPT,
    NetMsgType::CFCHECKPT,
    NetMsgType::WTXIDRELAY,
    NetMsgType::SENDTXRCNCL,
};

CMessageHeader::CMessageHeader(const MessageStartChars& pchMessageStartIn, const char* pszCommand, unsigned int nMessageSizeIn)
{
    memcpy(pchMessageStart, pchMessageStartIn, MESSAGE_START_SIZE);

    // Copy the command name
    size_t i = 0;
    for (; i < COMMAND_SIZE && pszCommand[i] != 0; ++i) pchCommand[i] = pszCommand[i];
    assert(pszCommand[i] == 0); // Assert that the command name passed in is not longer than COMMAND_SIZE

    nMessageSize = nMessageSizeIn;
}

std::string CMessageHeader::GetCommand() const
{
    return std::string(pchCommand, pchCommand + strnlen(pchCommand, COMMAND_SIZE));
}

bool CMessageHeader::IsCommandValid() const
{
    // Check the command string for errors
    for (const char* p1 = pchCommand; p1 < pchCommand + COMMAND_SIZE; ++p1) {
        if (*p1 == 0) {
            // Must be all zeros after the first zero
            for (; p1 < pchCommand + COMMAND_SIZE; ++p1) {
                if (*p1 != 0) {
                    return false;
                }
            }
        } else if (*p1 < ' ' || *p1 > 0x7E) {
            return false;
        }
    }

    return true;
}


ServiceFlags GetDesirableServiceFlags(ServiceFlags services) {
    if ((services & NODE_NETWORK_LIMITED) && g_initial_block_download_completed) {
        return ServiceFlags(NODE_NETWORK_LIMITED | NODE_WITNESS);
    }
    return ServiceFlags(NODE_NETWORK | NODE_WITNESS);
}

void SetServiceFlagsIBDCache(bool state) {
    g_initial_block_download_completed = state;
}

CInv::CInv()
{
    type = 0;
    hash.SetNull();
}

CInv::CInv(uint32_t typeIn, const uint256& hashIn) : type(typeIn), hash(hashIn) {}

bool operator<(const CInv& a, const CInv& b)
{
    return (a.type < b.type || (a.type == b.type && a.hash < b.hash));
}

std::string CInv::GetCommand() const
{
    std::string cmd;
    if (type & MSG_WITNESS_FLAG)
        cmd.append("witness-");
    int masked = type & MSG_TYPE_MASK;
    switch (masked)
    {
    case MSG_TX:             return cmd.append(NetMsgType::TX);
    // WTX is not a message type, just an inv type
    case MSG_WTX:            return cmd.append("wtx");
    case MSG_BLOCK:          return cmd.append(NetMsgType::BLOCK);
    case MSG_FILTERED_BLOCK: return cmd.append(NetMsgType::MERKLEBLOCK);
    case MSG_CMPCT_BLOCK:    return cmd.append(NetMsgType::CMPCTBLOCK);
    default:
        throw std::out_of_range(strprintf("CInv::GetCommand(): type=%d unknown type", type));
    }
}

std::string CInv::ToString() const
{
    try {
        return strprintf("%s %s", GetCommand(), hash.ToString());
    } catch(const std::out_of_range &) {
        return strprintf("0x%08x %s", type, hash.ToString());
    }
}

const std::vector<std::string> &getAllNetMessageTypes()
{
    return g_all_net_message_types;
}

/**
 * Convert a service flag (NODE_*) to a human readable string.
 * It supports unknown service flags which will be returned as "UNKNOWN[...]".
 * @param[in] bit the service flag is calculated as (1 << bit)
 */
static std::string serviceFlagToStr(size_t bit)
{
    const uint64_t service_flag = 1ULL << bit;
    switch ((ServiceFlags)service_flag) {
    case NODE_NONE: abort();  // impossible
    case NODE_NETWORK:         return "NETWORK";
    case NODE_BLOOM:           return "BLOOM";
    case NODE_WITNESS:         return "WITNESS";
    case NODE_COMPACT_FILTERS: return "COMPACT_FILTERS";
    case NODE_NETWORK_LIMITED: return "NETWORK_LIMITED";
    // Not using default, so we get warned when a case is missing
    }

    return strprintf("UNKNOWN[2^%u]", bit);
}

std::vector<std::string> serviceFlagsToStr(uint64_t flags)
{
    std::vector<std::string> str_flags;

    for (size_t i = 0; i < sizeof(flags) * 8; ++i) {
        if (flags & (1ULL << i)) {
            str_flags.emplace_back(serviceFlagToStr(i));
        }
    }

    return str_flags;
}

GenTxid ToGenTxid(const CInv& inv)
{
    assert(inv.IsGenTxMsg());
    return inv.IsMsgWtx() ? GenTxid::Wtxid(inv.hash) : GenTxid::Txid(inv.hash);
}