/*

  This file is part of solidity.

  solidity 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.

  solidity 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 solidity.  If not, see <http://www.gnu.org/licenses/>.

*/

// SPDX-License-Identifier: GPL-3.0

/** @file LinkerObject.cpp

 * @author Christian R <c@ethdev.com>

 * @date 2015

 */

#include <libevmasm/LinkerObject.h>

#include <libsolutil/CommonData.h>

#include <libsolutil/Keccak256.h>

using namespace std;

using namespace solidity;

using namespace solidity::util;

using namespace solidity::evmasm;

void LinkerObject::append(LinkerObject const& _other)

{

  for (auto const& ref: _other.linkReferences)

    linkReferences[ref.first + bytecode.size()] = ref.second;

  bytecode += _other.bytecode;

}

void LinkerObject::link(map<string, h160> const& _libraryAddresses)

{

  std::map<size_t, std::string> remainingRefs;

  for (auto const& linkRef: linkReferences)

    if (h160 const* address = matchLibrary(linkRef.second, _libraryAddresses))

      copy(address->data(), address->data() + 20, bytecode.begin() + vector<uint8_t>::difference_type(linkRef.first));

    else

      remainingRefs.insert(linkRef);

  linkReferences.swap(remainingRefs);

}

string LinkerObject::toHex() const

{

  string hex = solidity::util::toHex(bytecode);

  for (auto const& ref: linkReferences)

  {

    size_t pos = ref.first * 2;

    string hash = libraryPlaceholder(ref.second);

    hex[pos] = hex[pos + 1] = hex[pos + 38] = hex[pos + 39] = '_';

    for (size_t i = 0; i < 36; ++i)

      hex[pos + 2 + i] = hash.at(i);

  }

  return hex;

}

string LinkerObject::libraryPlaceholder(string const& _libraryName)

{

  return "$" + keccak256(_libraryName).hex().substr(0, 34) + "$";

}

h160 const*

LinkerObject::matchLibrary(

  string const& _linkRefName,

  map<string, h160> const& _libraryAddresses

)

{

  auto it = _libraryAddresses.find(_linkRefName);

  if (it != _libraryAddresses.end())

    return &it->second;

  return nullptr;

}