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// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers

/*!
 * \file gen_multisig.cpp
 * 
 * \brief Generates a set of multisig wallets
 */
#include <iostream>
#include <sstream>
#include <boost/program_options.hpp>
#include <boost/algorithm/string.hpp>
#include <boost/format.hpp>
#include "include_base_utils.h"
#include "crypto/crypto.h"  // for crypto::secret_key definition
#include "common/i18n.h"
#include "common/command_line.h"
#include "common/util.h"
#include "common/scoped_message_writer.h"
#include "wallet/wallet_args.h"
#include "wallet/wallet2.h"

using namespace std;
using namespace epee;
using namespace cryptonote;
using boost::lexical_cast;
namespace po = boost::program_options;

#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "wallet.gen_multisig"

namespace genms
{
  const char* tr(const char* str)
  {
    return i18n_translate(str, "tools::gen_multisig");
  }

}

namespace
{
  const command_line::arg_descriptor<std::string> arg_filename_base = {"filename-base", genms::tr("Base filename (-1, -2, etc suffixes will be appended as needed)"), ""};
  const command_line::arg_descriptor<std::string> arg_scheme = {"scheme", genms::tr("Give threshold and participants at once as M/N"), ""};
  const command_line::arg_descriptor<uint32_t> arg_participants = {"participants", genms::tr("How many participants will share parts of the multisig wallet"), 0};
  const command_line::arg_descriptor<uint32_t> arg_threshold = {"threshold", genms::tr("How many signers are required to sign a valid transaction"), 0};
  const command_line::arg_descriptor<bool, false> arg_testnet = {"testnet", genms::tr("Create testnet multisig wallets"), false};
  const command_line::arg_descriptor<bool, false> arg_stagenet = {"stagenet", genms::tr("Create stagenet multisig wallets"), false};
  const command_line::arg_descriptor<bool, false> arg_create_address_file = {"create-address-file", genms::tr("Create an address file for new wallets"), false};

  const command_line::arg_descriptor< std::vector<std::string> > arg_command = {"command", ""};
}

static bool generate_multisig(uint32_t threshold, uint32_t total, const std::string &basename, network_type nettype, bool create_address_file)
{
  tools::msg_writer() << (boost::format(genms::tr("Generating %u %u/%u multisig wallets")) % total % threshold % total).str();

  const auto pwd_container = tools::password_container::prompt(true, "Enter password for new multisig wallets");

  try
  {
    // create M wallets first
    std::vector<boost::shared_ptr<tools::wallet2>> wallets(total);
    for (size_t n = 0; n < total; ++n)
    {
      std::string name = basename + "-" + std::to_string(n + 1);
      wallets[n].reset(new tools::wallet2(nettype, 1, false));
      wallets[n]->init("");
      wallets[n]->generate(name, pwd_container->password(), rct::rct2sk(rct::skGen()), false, false, create_address_file);
    }

    // gather the keys
    std::vector<crypto::secret_key> sk(total);
    std::vector<crypto::public_key> pk(total);
    for (size_t n = 0; n < total; ++n)
    {
      wallets[n]->decrypt_keys(pwd_container->password());
      if (!tools::wallet2::verify_multisig_info(wallets[n]->get_multisig_info(), sk[n], pk[n]))
      {
        tools::fail_msg_writer() << genms::tr("Failed to verify multisig info");
        return false;
      }
      wallets[n]->encrypt_keys(pwd_container->password());
    }

    // make the wallets multisig
    std::vector<std::string> extra_info(total);
    std::stringstream ss;
    for (size_t n = 0; n < total; ++n)
    {
      std::string name = basename + "-" + std::to_string(n + 1);
      std::vector<crypto::secret_key> skn;
      std::vector<crypto::public_key> pkn;
      for (size_t k = 0; k < total; ++k)
      {
        if (k != n)
        {
          skn.push_back(sk[k]);
          pkn.push_back(pk[k]);
        }
      }
      extra_info[n] = wallets[n]->make_multisig(pwd_container->password(), skn, pkn, threshold);
      ss << "  " << name << std::endl;
    }

    // finalize step if needed
    if (!extra_info[0].empty())
    {
      std::unordered_set<crypto::public_key> pkeys;
      std::vector<crypto::public_key> signers(total);
      for (size_t n = 0; n < total; ++n)
      {
        if (!tools::wallet2::verify_extra_multisig_info(extra_info[n], pkeys, signers[n]))
        {
          tools::fail_msg_writer() << genms::tr("Error verifying multisig extra info");
          return false;
        }
      }
      for (size_t n = 0; n < total; ++n)
      {
        if (!wallets[n]->finalize_multisig(pwd_container->password(), pkeys, signers))
        {
          tools::fail_msg_writer() << genms::tr("Error finalizing multisig");
          return false;
        }
      }
    }

    std::string address = wallets[0]->get_account().get_public_address_str(wallets[0]->nettype());
    tools::success_msg_writer() << genms::tr("Generated multisig wallets for address ") << address << std::endl << ss.str();
  }
  catch (const std::exception &e)
  {
    tools::fail_msg_writer() << genms::tr("Error creating multisig wallets: ") << e.what();
    return false;
  }

  return true;
}

int main(int argc, char* argv[])
{
  TRY_ENTRY();

  po::options_description desc_params(wallet_args::tr("Wallet options"));
  command_line::add_arg(desc_params, arg_filename_base);
  command_line::add_arg(desc_params, arg_scheme);
  command_line::add_arg(desc_params, arg_threshold);
  command_line::add_arg(desc_params, arg_participants);
  command_line::add_arg(desc_params, arg_testnet);
  command_line::add_arg(desc_params, arg_stagenet);
  command_line::add_arg(desc_params, arg_create_address_file);

  boost::optional<po::variables_map> vm;
  bool should_terminate = false;
  std::tie(vm, should_terminate) = wallet_args::main(
   argc, argv,
   "monero-gen-multisig [(--testnet|--stagenet)] [--filename-base=<filename>] [--scheme=M/N] [--threshold=M] [--participants=N]",
    genms::tr("This program generates a set of multisig wallets - use this simpler scheme only if all the participants trust each other"),
    desc_params,
    boost::program_options::positional_options_description(),
    [](const std::string &s, bool emphasis){ tools::scoped_message_writer(emphasis ? epee::console_color_white : epee::console_color_default, true) << s; },
    "monero-gen-multisig.log"
  );
  if (!vm)
    return 1;
  if (should_terminate)
    return 0;

  bool testnet, stagenet;
  uint32_t threshold = 0, total = 0;
  std::string basename;

  testnet = command_line::get_arg(*vm, arg_testnet);
  stagenet = command_line::get_arg(*vm, arg_stagenet);
  if (testnet && stagenet)
  {
    tools::fail_msg_writer() << genms::tr("Error: Can't specify more than one of --testnet and --stagenet");
    return 1;
  }
  if (command_line::has_arg(*vm, arg_scheme))
  {
    if (sscanf(command_line::get_arg(*vm, arg_scheme).c_str(), "%u/%u", &threshold, &total) != 2)
    {
      tools::fail_msg_writer() << genms::tr("Error: expected N/M, but got: ") << command_line::get_arg(*vm, arg_scheme);
      return 1;
    }
  }
  if (!(*vm)["threshold"].defaulted())
  {
    if (threshold)
    {
      tools::fail_msg_writer() << genms::tr("Error: either --scheme or both of --threshold and --participants may be given");
      return 1;
    }
    threshold = command_line::get_arg(*vm, arg_threshold);
  }
  if (!(*vm)["participants"].defaulted())
  {
    if (total)
    {
      tools::fail_msg_writer() << genms::tr("Error: either --scheme or both of --threshold and --participants may be given");
      return 1;
    }
    total = command_line::get_arg(*vm, arg_participants);
  }
  if (threshold <= 1 || threshold > total)
  {
    tools::fail_msg_writer() << (boost::format(genms::tr("Error: expected N > 1 and N <= M, but got N==%u and M==%d")) % threshold % total).str();
    return 1;
  }
  if (!(*vm)["filename-base"].defaulted() && !command_line::get_arg(*vm, arg_filename_base).empty())
  {
    basename = command_line::get_arg(*vm, arg_filename_base);
  }
  else
  {
    tools::fail_msg_writer() << genms::tr("Error: --filename-base is required");
    return 1;
  }

  if (threshold != total-1 && threshold != total)
  {
    tools::fail_msg_writer() << genms::tr("Error: unsupported scheme: only N/N and N-1/N are supported");
    return 1;
  }
  bool create_address_file = command_line::get_arg(*vm, arg_create_address_file);
  if (!generate_multisig(threshold, total, basename, testnet ? TESTNET : stagenet ? STAGENET : MAINNET, create_address_file))
    return 1;

  return 0;
  CATCH_ENTRY_L0("main", 1);
}