thehub/hub/server/rpcmining.cpp

/*
 * This file is part of the Flowee project
 * Copyright (C) 2010 Satoshi Nakamoto
 * Copyright (C) 2009-2015 The Bitcoin Core developers
 * Copyright (C) 2017-2021 Tom Zander <tom@flowee.org>
 *
 * 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 3 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 <http://www.gnu.org/licenses/>.
 */

#include "Application.h"
#include "SettingsDefaults.h"
#include <validation/Engine.h>
#include "primitives/Block.h"
#include "chain.h"
#include "chainparams.h"
#include "core_io.h"
#include "main.h"
#include "miner.h"
#include "net.h"
#include "BlocksDB.h"
#include "pow.h"
#include "rpcserver.h"
#include "txmempool.h"
#include "util.h"
#include "utiltime.h"
#include "utilstrencodings.h"
#include "validationinterface.h"
#include <streaming/BufferPool.h>

#include <stdint.h>

#include <boost/assign/list_of.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/foreach.hpp>

#include <univalue.h>

/**
 * Return average network hashes per second based on the last 'lookup' blocks,
 * or from the last difficulty change if 'lookup' is nonpositive.
 * If 'height' is nonnegative, compute the estimate at the time when a given block was found.
 */
UniValue GetNetworkHashPS(int lookup, int height) {
    CBlockIndex *pb = chainActive.Tip();

    if (height >= 0 && height < chainActive.Height())
        pb = chainActive[height];

    if (pb == NULL || !pb->nHeight)
        return 0;

    // If lookup is -1, then use blocks since last difficulty change.
    if (lookup <= 0)
        lookup = pb->nHeight % Params().GetConsensus().DifficultyAdjustmentInterval() + 1;

    // If lookup is larger than chain, then set it to chain length.
    if (lookup > pb->nHeight)
        lookup = pb->nHeight;

    CBlockIndex *pb0 = pb;
    int64_t minTime = pb0->GetBlockTime();
    int64_t maxTime = minTime;
    for (int i = 0; i < lookup; i++) {
        pb0 = pb0->pprev;
        int64_t time = pb0->GetBlockTime();
        minTime = std::min(time, minTime);
        maxTime = std::max(time, maxTime);
    }

    // In case there's a situation where minTime == maxTime, we don't want a divide by zero exception.
    if (minTime == maxTime)
        return 0;

    arith_uint256 workDiff = pb->nChainWork - pb0->nChainWork;
    int64_t timeDiff = maxTime - minTime;

    return workDiff.getdouble() / timeDiff;
}

UniValue getnetworkhashps(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() > 2)
        throw std::runtime_error(
            "getnetworkhashps ( blocks height )\n"
            "\nReturns the estimated network hashes per second based on the last n blocks.\n"
            "Pass in [blocks] to override # of blocks, -1 specifies since last difficulty change.\n"
            "Pass in [height] to estimate the network speed at the time when a certain block was found.\n"
            "\nArguments:\n"
            "1. blocks     (numeric, optional, default=120) The number of blocks, or -1 for blocks since last difficulty change.\n"
            "2. height     (numeric, optional, default=-1) To estimate at the time of the given height.\n"
            "\nResult:\n"
            "x             (numeric) Hashes per second estimated\n"
            "\nExamples:\n"
            + HelpExampleCli("getnetworkhashps", "")
            + HelpExampleRpc("getnetworkhashps", "")
       );

    LOCK(cs_main);
    return GetNetworkHashPS(params.size() > 0 ? params[0].get_int() : 120, params.size() > 1 ? params[1].get_int() : -1);
}

UniValue getgenerate(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 0)
        throw std::runtime_error(
            "getgenerate\n"
            "\nReturn if the server is set to generate coins or not. The default is false.\n"
            "It is set with the command line argument -gen (or " + std::string(Settings::hubConfFilename()) + " setting gen)\n"
            "It can also be set with the setgenerate call.\n"
            "\nResult\n"
            "true|false      (boolean) If the server is set to generate coins or not\n"
            "\nExamples:\n"
            + HelpExampleCli("getgenerate", "")
            + HelpExampleRpc("getgenerate", "")
        );

    LOCK(cs_main);
    return GetBoolArg("-gen", Settings::DefaultGenerateCoins);
}

UniValue generate(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() < 2 || params.size() > 2)
        throw std::runtime_error(
            "generate numblocks coinbase\n"
            "\nMine blocks immediately (before the RPC call returns)\n"
            "\nNote: this function can only be used on the regtest network\n"
            "\nArguments:\n"
            "1. numblocks    (numeric, required) How many blocks are generated immediately.\n"
            "2. coinbase     (string, required) the hash160 (bitcoin address) for the coinbase\n"
            "\nResult\n"
            "[ blockhashes ]     (array) hashes of blocks generated\n"
            "\nExamples:\n"
            "\nGenerate 11 blocks\n"
            + HelpExampleCli("generate", "11")
        );

    if (!Params().MineBlocksOnDemand())
        throw JSONRPCError(RPC_METHOD_NOT_FOUND, "This method can only be used on regtest");

    int nHeightStart = 0;
    int nHeightEnd = 0;
    int nHeight = 0;
    int nGenerate = params[0].get_int();

    CScript coinbase = Mining::ScriptForCoinbase(params[1].get_str());

    {   // Don't keep cs_main locked
        LOCK(cs_main);
        nHeightStart = chainActive.Height();
        nHeight = nHeightStart;
        nHeightEnd = nHeightStart+nGenerate;
    }

    Mining *miningInstance = Mining::instance();
    miningInstance->SetCoinbase(coinbase);
    unsigned int nExtraNonce = 0;
    UniValue blockHashes(UniValue::VARR);
    Streaming::BufferPool pool;
    auto *bv = Application::instance()->validation();
    while (nHeight < nHeightEnd)
    {
        std::unique_ptr<CBlockTemplate> pblocktemplate(miningInstance->CreateNewBlock());
        if (!pblocktemplate.get())
            throw JSONRPCError(RPC_INTERNAL_ERROR, "Couldn't create new block");
        MutableBlock *pblock = &pblocktemplate->block;
        {
            LOCK(cs_main);
            miningInstance->IncrementExtraNonce(pblock, chainActive.Tip(), nExtraNonce);
        }
        while (!CheckProofOfWork(pblock->createHash(), pblock->nBits, Params().GetConsensus())) {
            // Yes, there is a chance every nonce could fail to satisfy the -regtest
            // target -- 1 in 2^(2^32). That ain't gonna happen.
            ++pblock->nNonce;
        }

        auto blockFuture = bv->addBlock(Block::fromOldBlock(*pblock, &pool),
                Validation::ForwardGoodToPeers | Validation::SaveGoodToDisk).start();
        ++nHeight;
        blockHashes.push_back(pblock->createHash().GetHex());
        blockFuture.waitUntilFinished();
    }
    return blockHashes;
}

UniValue setgenerate(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() < 1 || params.size() > 2)
        throw std::runtime_error(
            "setgenerate generate ( genproclimit )\n"
            "\nSet 'generate' true or false to turn generation on or off.\n"
            "Generation is limited to 'genproclimit' processors, -1 is unlimited.\n"
            "See the getgenerate call for the current setting.\n"
            "\nArguments:\n"
            "1. generate         (boolean, required) Set to true to turn on generation, off to turn off.\n"
            "2. genproclimit     (numeric, optional) Set the processor limit for when generation is on. Can be -1 for unlimited.\n"
            "\nExamples:\n"
            "\nSet the generation on with a limit of one processor\n"
            + HelpExampleCli("setgenerate", "true 1") +
            "\nCheck the setting\n"
            + HelpExampleCli("getgenerate", "") +
            "\nTurn off generation\n"
            + HelpExampleCli("setgenerate", "false") +
            "\nUsing json rpc\n"
            + HelpExampleRpc("setgenerate", "true, 1")
        );

    if (Params().MineBlocksOnDemand())
        throw JSONRPCError(RPC_METHOD_NOT_FOUND, "Use the generate method instead of setgenerate on this network");

    bool fGenerate = true;
    if (params.size() > 0)
        fGenerate = params[0].get_bool();

    int nGenProcLimit = GetArg("-genproclimit", Settings::DefaultGenerateThreads);
    if (params.size() > 1)
    {
        nGenProcLimit = params[1].get_int();
        if (nGenProcLimit == 0)
            fGenerate = false;
    }

    mapArgs["-gen"] = (fGenerate ? "1" : "0");
    mapArgs ["-genproclimit"] = itostr(nGenProcLimit);
    std::string coinbase = GetArg("-gencoinbase", "");
    if (coinbase.empty())
        throw JSONRPCError(RPC_INVALID_PARAMETER, "Please use the commandline argument -gencoinbase to set a coinbase");

    Mining::GenerateBitcoins(fGenerate, nGenProcLimit, Params(), coinbase);

    return NullUniValue;
}

UniValue getmininginfo(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 0)
        throw std::runtime_error(
            "getmininginfo\n"
            "\nReturns a json object containing mining-related information."
            "\nResult:\n"
            "{\n"
            "  \"blocks\": nnn,             (numeric) The current block\n"
            "  \"currentblocksize\": nnn,   (numeric) The last block size\n"
            "  \"currentblocktx\": nnn,     (numeric) The last block transaction\n"
            "  \"difficulty\": xxx.xxxxx    (numeric) The current difficulty\n"
            "  \"errors\": \"...\"          (string) Current errors\n"
            "  \"generate\": true|false     (boolean) If the generation is on or off (see getgenerate or setgenerate calls)\n"
            "  \"genproclimit\": n          (numeric) The processor limit for generation. -1 if no generation. (see getgenerate or setgenerate calls)\n"
            "  \"pooledtx\": n              (numeric) The size of the mem pool\n"
            "  \"testnet\": true|false      (boolean) If using testnet or not\n"
            "  \"chain\": \"xxxx\",         (string) current network name as defined in BIP70 (main, test, regtest)\n"
            "}\n"
            "\nExamples:\n"
            + HelpExampleCli("getmininginfo", "")
            + HelpExampleRpc("getmininginfo", "")
        );


    LOCK(cs_main);

    UniValue obj(UniValue::VOBJ);
    obj.push_back(Pair("blocks",           (int)chainActive.Height()));
    obj.push_back(Pair("currentblocksize", (uint64_t)nLastBlockSize));
    obj.push_back(Pair("currentblocktx",   (uint64_t)nLastBlockTx));
    obj.push_back(Pair("difficulty",       (double)GetDifficulty()));
    obj.push_back(Pair("errors",           GetWarnings("statusbar")));
    obj.push_back(Pair("genproclimit",     (int)GetArg("-genproclimit", Settings::DefaultGenerateThreads)));
    obj.push_back(Pair("networkhashps",    getnetworkhashps(params, false)));
    obj.push_back(Pair("pooledtx",         (uint64_t)mempool.size()));
    obj.push_back(Pair("testnet",          Params().TestnetToBeDeprecatedFieldRPC()));
    obj.push_back(Pair("chain",            Params().NetworkIDString()));
    obj.push_back(Pair("generate",         getgenerate(params, false)));
    return obj;
}


// NOTE: Unlike wallet RPC (which use BCH values), mining RPCs follow GBT (BIP 22) in using satoshi amounts
UniValue prioritisetransaction(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 3)
        throw std::runtime_error(
            "prioritisetransaction <txid> <priority delta> <fee delta>\n"
            "Accepts the transaction into mined blocks at a higher (or lower) priority\n"
            "\nArguments:\n"
            "1. \"txid\"       (string, required) The transaction id.\n"
            "2. priority delta (numeric, required) The priority to add or subtract.\n"
            "                  The transaction selection algorithm considers the tx as it would have a higher priority.\n"
            "                  (priority of a transaction is calculated: coinage * value_in_satoshis / txsize) \n"
            "3. fee delta      (numeric, required) The fee value (in satoshis) to add (or subtract, if negative).\n"
            "                  The fee is not actually paid, only the algorithm for selecting transactions into a block\n"
            "                  considers the transaction as it would have paid a higher (or lower) fee.\n"
            "\nResult\n"
            "true              (boolean) Returns true\n"
            "\nExamples:\n"
            + HelpExampleCli("prioritisetransaction", "\"txid\" 0.0 10000")
            + HelpExampleRpc("prioritisetransaction", "\"txid\", 0.0, 10000")
        );

    LOCK(cs_main);

    uint256 hash = ParseHashStr(params[0].get_str(), "txid");
    int64_t nAmount = params[2].get_int64();

    mempool.PrioritiseTransaction(hash, params[0].get_str(), params[1].get_real(), nAmount);
    return true;
}


UniValue getblocktemplate(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() > 1)
        throw std::runtime_error(
            "getblocktemplate ( \"jsonrequestobject\" )\n"
            "\nIf the request parameters include a 'mode' key, that is used to explicitly select between the default 'template' request or a 'proposal'.\n"
            "It returns data needed to construct a block to work on.\n"
            "See https://github.com/bitcoin/bips/blob/master/bip-0022.mediawiki for full specification.\n"

            "\nArguments:\n"
            "1. \"jsonrequestobject\"       (string, optional) A json object in the following spec\n"
            "     {\n"
            "       \"mode\":\"template\"    (string, optional) This must be set to \"template\" or omitted\n"
            "       \"capabilities\":[       (array, optional) A list of strings\n"
            "           \"support\"           (string) client side supported feature, 'longpoll', 'coinbasetxn', 'coinbasevalue', 'proposal', 'serverlist', 'workid'\n"
            "           ,...\n"
            "         ]\n"
            "     }\n"
            "\n"

            "\nResult:\n"
            "{\n"
            "  \"version\" : n,                    (numeric) The block version\n"
            "  \"previousblockhash\" : \"xxxx\",    (string) The hash of current highest block\n"
            "  \"transactions\" : [                (array) contents of non-coinbase transactions that should be included in the next block\n"
            "      {\n"
            "         \"data\" : \"xxxx\",          (string) transaction data encoded in hexadecimal (byte-for-byte)\n"
            "         \"hash\" : \"xxxx\",          (string) hash/id encoded in little-endian hexadecimal\n"
            "         \"depends\" : [              (array) array of numbers \n"
            "             n                        (numeric) transactions before this one (by 1-based index in 'transactions' list) that must be present in the final block if this one is\n"
            "             ,...\n"
            "         ],\n"
            "         \"fee\": n,                   (numeric) difference in value between transaction inputs and outputs (in Satoshis); for coinbase transactions, this is a negative Number of the total collected block fees (ie, not including the block subsidy); if key is not present, fee is unknown and clients MUST NOT assume there isn't one\n"
            "         \"sigops\" : n,               (numeric) total number of SigOps, as counted for purposes of block limits; if key is not present, sigop count is unknown and clients MUST NOT assume there aren't any\n"
            "         \"required\" : true|false     (boolean) if provided and true, this transaction must be in the final block\n"
            "      }\n"
            "      ,...\n"
            "  ],\n"
            "  \"coinbaseaux\" : {                  (json object) data that should be included in the coinbase's scriptSig content\n"
            "      \"flags\" : \"flags\"            (string) \n"
            "  },\n"
            "  \"coinbasevalue\" : n,               (numeric) maximum allowable input to coinbase transaction, including the generation award and transaction fees (in Satoshis)\n"
            "  \"coinbasetxn\" : { ... },           (json object) information for coinbase transaction\n"
            "  \"target\" : \"xxxx\",               (string) The hash target\n"
            "  \"mintime\" : xxx,                   (numeric) The minimum timestamp appropriate for next block time in seconds since epoch (Jan 1 1970 GMT)\n"
            "  \"mutable\" : [                      (array of string) list of ways the block template may be changed \n"
            "     \"value\"                         (string) A way the block template may be changed, e.g. 'time', 'transactions', 'prevblock'\n"
            "     ,...\n"
            "  ],\n"
            "  \"noncerange\" : \"00000000ffffffff\",   (string) A range of valid nonces\n"
            "  \"sigoplimit\" : n,                 (numeric) limit of sigops in blocks\n"
            "  \"sizelimit\" : n,                  (numeric) limit of block size. (deprecated)\n"
            "  \"curtime\" : ttt,                  (numeric) current timestamp in seconds since epoch (Jan 1 1970 GMT)\n"
            "  \"bits\" : \"xxx\",                 (string) compressed target of next block\n"
            "  \"height\" : n                      (numeric) The height of the next block\n"
            "}\n"

            "\nExamples:\n"
            + HelpExampleCli("getblocktemplate", "")
            + HelpExampleRpc("getblocktemplate", "")
         );

    std::string strMode = "template";
    UniValue lpval = NullUniValue;
    if (params.size() > 0)
    {
        const UniValue& oparam = params[0].get_obj();
        const UniValue& modeval = find_value(oparam, "mode");
        if (modeval.isStr())
            strMode = modeval.get_str();
        else if (modeval.isNull())
        {
            /* Do nothing */
        }
        else
            throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid mode");
        lpval = find_value(oparam, "longpollid");

        if (strMode == "proposal")
        {
            const UniValue& dataval = find_value(oparam, "data");
            if (!dataval.isStr())
                throw JSONRPCError(RPC_TYPE_ERROR, "Missing data String key for proposal");

            MutableBlock block;
            if (!DecodeHexBlk(block, dataval.get_str()))
                throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Block decode failed");

            uint256 hash = block.createHash();
            CBlockIndex *pindex = Blocks::Index::get(hash);
            if (pindex) {
                if (pindex->IsValid(BLOCK_VALID_SCRIPTS))
                    return "duplicate";
                if (pindex->nStatus & BLOCK_FAILED_MASK)
                    return "duplicate-invalid";
                return "duplicate-inconclusive";
            }

            CBlockIndex* const pindexPrev = chainActive.Tip();
            // TestBlockValidity only supports blocks built on the current Tip
            if (block.hashPrevBlock != pindexPrev->GetBlockHash())
                return "inconclusive-not-best-prevblk";
            auto settings = Application::instance()->validation()->addBlock(Block::fromOldBlock(block), 0);
            settings.setCheckPoW(false);
            settings.setOnlyCheckValidity(true);
            settings.start();
            settings.waitUntilFinished();
            if (settings.error().empty())
                return NullUniValue;
            return settings.error();
        }
    }

    if (strMode != "template")
        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid mode");

    if (vNodes.empty())
        throw JSONRPCError(RPC_CLIENT_NOT_CONNECTED, "Bitcoin is not connected!");

    if (IsInitialBlockDownload())
        throw JSONRPCError(RPC_CLIENT_IN_INITIAL_DOWNLOAD, "Bitcoin is downloading blocks...");

    static unsigned int nTransactionsUpdatedLast;

    LOCK(cs_main);
    if (!lpval.isNull())
    {
        // Wait to respond until either the best block changes, OR a minute has passed and there are more transactions
        uint256 hashWatchedChain;
        boost::system_time checktxtime;
        unsigned int nTransactionsUpdatedLastLP;

        if (lpval.isStr())
        {
            // Format: <hashBestChain><nTransactionsUpdatedLast>
            std::string lpstr = lpval.get_str();

            hashWatchedChain.SetHex(lpstr.substr(0, 64));
            nTransactionsUpdatedLastLP = atoi64(lpstr.substr(64));
        }
        else
        {
            // NOTE: Spec does not specify behaviour for non-string longpollid, but this makes testing easier
            hashWatchedChain = chainActive.Tip()->GetBlockHash();
            nTransactionsUpdatedLastLP = nTransactionsUpdatedLast;
        }

        // Release the wallet and main lock while waiting
        LEAVE_CRITICAL_SECTION(cs_main)
        {
            checktxtime = boost::get_system_time() + boost::posix_time::minutes(1);

            boost::unique_lock<boost::mutex> lock(csBestBlock);
            while (chainActive.Tip()->GetBlockHash() == hashWatchedChain && IsRPCRunning())
            {
                if (!cvBlockChange.timed_wait(lock, checktxtime))
                {
                    // Timeout: Check transactions for update
                    if (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLastLP)
                        break;
                    checktxtime += boost::posix_time::seconds(10);
                }
            }
        }
        ENTER_CRITICAL_SECTION(cs_main)

        if (!IsRPCRunning())
            throw JSONRPCError(RPC_CLIENT_NOT_CONNECTED, "Shutting down");
        // TODO: Maybe recheck connections/IBD and (if something wrong) send an expires-immediately template to stop miners?
    }

    // Update block
    static CBlockIndex* pindexPrev;
    static int64_t nStart;
    static CBlockTemplate* pblocktemplate;
    if (pindexPrev != chainActive.Tip() ||
        (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLast && GetTime() - nStart > 5))
    {
        // Clear pindexPrev so future calls make a new block, despite any failures from here on
        pindexPrev = NULL;

        // Store the pindexBest used before CreateNewBlock, to avoid races
        nTransactionsUpdatedLast = mempool.GetTransactionsUpdated();
        CBlockIndex* pindexPrevNew = chainActive.Tip();
        nStart = GetTime();

        // Create new block
        if(pblocktemplate)
        {
            delete pblocktemplate;
            pblocktemplate = NULL;
        }
        Mining mining;
        CScript scriptDummy = CScript() << OP_TRUE;
        mining.SetCoinbase(scriptDummy);
        LEAVE_CRITICAL_SECTION(cs_main)
        pblocktemplate = mining.CreateNewBlock(*Application::instance()->validation());
        if (!pblocktemplate)
            throw JSONRPCError(RPC_OUT_OF_MEMORY, "Out of memory");
        ENTER_CRITICAL_SECTION(cs_main)

        // Need to update only after we know CreateNewBlock succeeded
        pindexPrev = pindexPrevNew;
    }
    MutableBlock* pblock = &pblocktemplate->block; // pointer for convenience

    // Update nTime
    Mining::UpdateTime(*pblock, Params().GetConsensus(), pindexPrev);
    pblock->nNonce = 0;

    UniValue aCaps(UniValue::VARR); aCaps.push_back("proposal");

    UniValue transactions(UniValue::VARR);
    std::map<uint256, int64_t> setTxIndex;
    size_t i = 0;
    BOOST_FOREACH (const CTransaction& tx, pblock->vtx) {
        uint256 txHash = tx.GetHash();
        setTxIndex[txHash] = i++;

        if (tx.IsCoinBase())
            continue;

        UniValue entry(UniValue::VOBJ);

        entry.push_back(Pair("data", EncodeHexTx(tx)));

        entry.push_back(Pair("hash", txHash.GetHex()));

        UniValue deps(UniValue::VARR);
        BOOST_FOREACH (const CTxIn &in, tx.vin)
        {
            if (setTxIndex.count(in.prevout.hash))
                deps.push_back(setTxIndex[in.prevout.hash]);
        }
        entry.push_back(Pair("depends", deps));

        assert(i > 0);
        size_t index_in_template = i - 1;
        entry.push_back(Pair("fee", pblocktemplate->vTxFees[index_in_template]));
        entry.push_back(Pair("sigops", 0));

        transactions.push_back(entry);
    }

    arith_uint256 hashTarget = arith_uint256().SetCompact(pblock->nBits);

    static UniValue aMutable(UniValue::VARR);
    if (aMutable.empty())
    {
        aMutable.push_back("time");
        aMutable.push_back("transactions");
        aMutable.push_back("prevblock");
    }

    UniValue result(UniValue::VOBJ);
    result.push_back(Pair("capabilities", aCaps));
    result.push_back(Pair("version", pblock->nVersion));
    result.push_back(Pair("previousblockhash", pblock->hashPrevBlock.GetHex()));
    result.push_back(Pair("transactions", transactions));
    result.push_back(Pair("coinbasevalue", (int64_t)pblock->vtx[0].vout[0].nValue));
    result.push_back(Pair("longpollid", chainActive.Tip()->GetBlockHash().GetHex() + i64tostr(nTransactionsUpdatedLast)));
    result.push_back(Pair("target", hashTarget.GetHex()));
    result.push_back(Pair("mintime", (int64_t)pindexPrev->GetMedianTimePast()+1));
    result.push_back(Pair("mutable", aMutable));
    result.push_back(Pair("noncerange", "00000000ffffffff"));
    int64_t sizeLimit = 32E6; // lets have a nice big default, the goal is to remove this from the API
    result.push_back(Pair("sigoplimit", 100000)); // obsolete
    result.push_back(Pair("sizelimit", sizeLimit));
    result.push_back(Pair("curtime", pblock->blockTime()));
    result.push_back(Pair("bits", strprintf("%08x", pblock->nBits)));
    result.push_back(Pair("height", (int64_t)(pindexPrev->nHeight+1)));

    return result;
}

UniValue submitblock(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() < 1 || params.size() > 2)
        throw std::runtime_error(
            "submitblock \"hexdata\" ( \"jsonparametersobject\" )\n"
            "\nAttempts to submit new block to network.\n"
            "The 'jsonparametersobject' parameter is currently ignored.\n"
            "See https://en.bitcoin.it/wiki/BIP_0022 for full specification.\n"

            "\nArguments\n"
            "1. \"hexdata\"    (string, required) the hex-encoded block data to submit\n"
            "2. \"jsonparametersobject\"     (string, optional) object of optional parameters\n"
            "    {\n"
            "      \"workid\" : \"id\"    (string, optional) if the server provided a workid, it MUST be included with submissions\n"
            "    }\n"
            "\nResult:\n"
            "\nExamples:\n"
            + HelpExampleCli("submitblock", "\"mydata\"")
            + HelpExampleRpc("submitblock", "\"mydata\"")
        );

    MutableBlock block;
    if (!DecodeHexBlk(block, params[0].get_str()))
        throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Block decode failed");

    uint256 hash = block.createHash();
    {
        CBlockIndex *pindex = Blocks::Index::get(hash);
        if (pindex) {
            if (Blocks::DB::instance()->headerChain().Contains(pindex))
                return "duplicate";
            if (pindex->nStatus & BLOCK_FAILED_MASK)
                return "duplicate-invalid";
            // Otherwise, we might only have the header - process the block before returning
        }
    }

    auto future = Application::instance()->validation()->addBlock(Block::fromOldBlock(block), Validation::SaveGoodToDisk | Validation::ForwardGoodToPeers);
    future.start();
    future.waitUntilFinished();
    auto index = future.blockIndex();
    if (index && future.error().empty() && index->IsValid()) // all Ok
        return NullUniValue;

    if (!future.error().empty())
        throw JSONRPCError(RPC_VERIFY_ERROR, future.error());

    if (index)
        return "rejected";
    return "accepted";
}

UniValue estimatefee(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 1)
        throw std::runtime_error(
            "estimatefee nblocks\n"
            "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n"
            "confirmation within nblocks blocks.\n"
            "\nArguments:\n"
            "1. nblocks     (numeric)\n"
            "\nResult:\n"
            "n              (numeric) estimated fee-per-kilobyte\n"
            "\n"
            "A negative value is returned if not enough transactions and blocks\n"
            "have been observed to make an estimate.\n"
            "\nExample:\n"
            + HelpExampleCli("estimatefee", "6")
            );

    RPCTypeCheck(params, boost::assign::list_of(UniValue::VNUM));
    return -1.0;
}

UniValue estimatepriority(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 1)
        throw std::runtime_error(
            "estimatepriority nblocks\n"
            "\nEstimates the approximate priority a zero-fee transaction needs to begin\n"
            "confirmation within nblocks blocks.\n"
            "\nArguments:\n"
            "1. nblocks     (numeric)\n"
            "\nResult:\n"
            "n              (numeric) estimated priority\n"
            "\n"
            "A negative value is returned if not enough transactions and blocks\n"
            "have been observed to make an estimate.\n"
            "\nExample:\n"
            + HelpExampleCli("estimatepriority", "6")
            );

    RPCTypeCheck(params, boost::assign::list_of(UniValue::VNUM));
    return -1;
}

UniValue estimatesmartfee(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 1)
        throw std::runtime_error(
            "estimatesmartfee nblocks\n"
            "\nWARNING: This interface is unstable and may disappear or change!\n"
            "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n"
            "confirmation within nblocks blocks if possible and return the number of blocks\n"
            "for which the estimate is valid.\n"
            "\nArguments:\n"
            "1. nblocks     (numeric)\n"
            "\nResult:\n"
            "{\n"
            "  \"feerate\" : x.x,     (numeric) estimate fee-per-kilobyte (in BCH)\n"
            "  \"blocks\" : n         (numeric) block number where estimate was found\n"
            "}\n"
            "\n"
            "A negative value is returned if not enough transactions and blocks\n"
            "have been observed to make an estimate for any number of blocks.\n"
            "However it will not return a value below the mempool reject fee.\n"
            "\nExample:\n"
            + HelpExampleCli("estimatesmartfee", "6")
            );

    RPCTypeCheck(params, boost::assign::list_of(UniValue::VNUM));

    UniValue result(UniValue::VOBJ);
    result.push_back(Pair("feerate", -1));
    result.push_back(Pair("blocks", 0));
    return result;
}

UniValue estimatesmartpriority(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 1)
        throw std::runtime_error(
            "estimatesmartpriority nblocks\n"
            "\nWARNING: This interface is unstable and may disappear or change!\n"
            "\nEstimates the approximate priority a zero-fee transaction needs to begin\n"
            "confirmation within nblocks blocks if possible and return the number of blocks\n"
            "for which the estimate is valid.\n"
            "\nArguments:\n"
            "1. nblocks     (numeric)\n"
            "\nResult:\n"
            "{\n"
            "  \"priority\" : x.x,    (numeric) estimated priority\n"
            "  \"blocks\" : n         (numeric) block number where estimate was found\n"
            "}\n"
            "\n"
            "A negative value is returned if not enough transactions and blocks\n"
            "have been observed to make an estimate for any number of blocks.\n"
            "However if the mempool reject fee is set it will return 1e9 * MAX_MONEY.\n"
            "\nExample:\n"
            + HelpExampleCli("estimatesmartpriority", "6")
            );

    RPCTypeCheck(params, boost::assign::list_of(UniValue::VNUM));

    UniValue result(UniValue::VOBJ);
    result.push_back(Pair("priority", -1));
    result.push_back(Pair("blocks", 0));
    return result;
}

UniValue setcoinbase(const UniValue& params, bool fHelp)
{
    if (fHelp || params.size() != 1)
        throw std::runtime_error(
            "setcoinbase pubkey\n"
            "\nwhen called this registers a public key to be used as a coinbase for subsequent\n"
            "calls to getblocktemplate\n"
            "\nArguments:\n"
            "1. pubkey     (hex)  the raw (hex encoded) pubkey\n"
            "\n"
            );


    auto script = Mining::ScriptForCoinbase(params[0].get_str());
    Mining::instance()->SetCoinbase(script);
    return  UniValue(UniValue::VOBJ);
}

UniValue validateblocktemplate(const UniValue &params, bool fHelp)
{
    if (fHelp || params.size() < 1 || params.size() > 1)
        throw std::runtime_error(
            "validateblocktemplate \"hexdata\"\n"
            "\nReturns whether this block template will be accepted if a hash solution is found.\n"
            "See https://en.bitcoin.it/wiki/BIP_0022 for full specification.\n"

            "\nArguments\n"
            "1. \"hexdata\"    (string, required) the hex-encoded block to validate (same format as submitblock)\n"
            "\nResult:\n"
            "true (boolean) submitted block template is valid\n"
            "JSONRPCException if submitted block template is invalid\n");

    Block block;
    {   // go via the old serialization since it does extra checks right here.
        MutableBlock oldBlock;
        if (!DecodeHexBlk(oldBlock, params[0].get_str()))
            throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Block decode failed");
        block = Block::fromOldBlock(oldBlock);
    }

    auto pindexPrev = Blocks::Index::get(block.previousBlockId());
    if (!pindexPrev)
        throw std::runtime_error("invalid block: unknown parent");
    if (pindexPrev != chainActive.Tip())
        throw std::runtime_error("invalid block: does not build on chain tip");
    auto settings = Application::instance()->validation()->addBlock(block, 0);
    settings.setCheckMerkleRoot(true);
    settings.setCheckPoW(false);
    settings.setOnlyCheckValidity(true);
    logInfo(Log::RPC) << "Block submitted for validation" << block.createHash() << block.size() << "bytes";
    settings.start();
    logInfo(Log::RPC) << "Validation started";
    settings.waitUntilFinished();
    logInfo(Log::RPC) << "Validation finished with:" << settings.error();
    if (!settings.error().empty())
        throw std::runtime_error(std::string("invalid block: ") + settings.error());

    return UniValue(true);
}