/*

  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

#include <libyul/optimiser/UnusedFunctionsCommon.h>

#include <libyul/Dialect.h>

#include <libsolutil/CommonData.h>

using namespace solidity;

using namespace solidity::util;

using namespace solidity::yul;

using namespace solidity::yul::unusedFunctionsCommon;

FunctionDefinition unusedFunctionsCommon::createLinkingFunction(

  FunctionDefinition const& _original,

  std::pair<std::vector<bool>, std::vector<bool>> const& _usedParametersAndReturns,

  YulName const& _originalFunctionName,

  YulName const& _linkingFunctionName,

  NameDispenser& _nameDispenser

)

{

  auto generateTypedName = [&](NameWithDebugData t)

  {

    return NameWithDebugData{

      t.debugData,

      _nameDispenser.newName(t.name)

    };

  };

  FunctionDefinition linkingFunction{

    _original.debugData,

    _linkingFunctionName,

    util::applyMap(_original.parameters, generateTypedName),

    util::applyMap(_original.returnVariables, generateTypedName),

    {_original.debugData, {}} // body

  };

  FunctionCall call{_original.debugData, Identifier{_original.debugData, _originalFunctionName}, {}};

  for (auto const& p: filter(linkingFunction.parameters, _usedParametersAndReturns.first))

    call.arguments.emplace_back(Identifier{_original.debugData, p.name});

  Assignment assignment{_original.debugData, {}, nullptr};

  for (auto const& r: filter(linkingFunction.returnVariables, _usedParametersAndReturns.second))

    assignment.variableNames.emplace_back(Identifier{_original.debugData, r.name});

  if (assignment.variableNames.empty())

    linkingFunction.body.statements.emplace_back(ExpressionStatement{_original.debugData, std::move(call)});

  else

  {

    assignment.value = std::make_unique<Expression>(std::move(call));

    linkingFunction.body.statements.emplace_back(std::move(assignment));

  }

  return linkingFunction;

}