/* Copyright 2017 - 2026 R. Thomas
 * Copyright 2017 - 2026 Quarkslab
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include "logging.hpp"
#include "LIEF/Visitor.hpp"
#include "LIEF/endianness_support.hpp"

#include "LIEF/MachO/ThreadCommand.hpp"
#include "MachO/Structures.hpp"

namespace LIEF::MachO {

template<class T>
inline T from_big_endian(T value) {
#ifdef __BYTE_ORDER__
  #if defined(__ORDER_LITTLE_ENDIAN__) &&                                         \
      (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
  return get_swapped_endian<T>(value);
  #else
  return value;
  #endif
#else
  // No __BYTE_ORDER__ (e.g. MSVC): assume a little-endian host.
  return get_swapped_endian<T>(value);
#endif
}

ThreadCommand::ThreadCommand(const details::thread_command& cmd,
                             Header::CPU_TYPE arch) :
  LoadCommand::LoadCommand{LoadCommand::TYPE(cmd.cmd), cmd.cmdsize},
  flavor_{cmd.flavor},
  count_{cmd.count},
  architecture_{arch} {}

ThreadCommand::ThreadCommand(uint32_t flavor, uint32_t count,
                             Header::CPU_TYPE arch) :
  LoadCommand::LoadCommand{LoadCommand::TYPE::UNIXTHREAD,
                           static_cast<uint32_t>(sizeof(details::thread_command) +
                                                 count * sizeof(uint32_t))},
  flavor_{flavor},
  count_{count},
  architecture_{arch},
  state_(size() - sizeof(details::thread_command), 0) {}

uint64_t ThreadCommand::pc() const {
  uint64_t entry = 0;
  switch (architecture_) {
    case Header::CPU_TYPE::X86:
    {
      if (state_.size() < sizeof(details::x86_thread_state_t)) {
        return entry;
      }
      entry =
          reinterpret_cast<const details::x86_thread_state_t*>(state_.data())->eip;
      break;
    }

    case Header::CPU_TYPE::X86_64:
    {
      if (state_.size() < sizeof(details::x86_thread_state64_t)) {
        return entry;
      }
      entry = reinterpret_cast<const details::x86_thread_state64_t*>(state_.data())
                  ->rip;
      break;
    }

    case Header::CPU_TYPE::ARM:
    {
      if (state_.size() < sizeof(details::arm_thread_state_t)) {
        return entry;
      }
      entry =
          reinterpret_cast<const details::arm_thread_state_t*>(state_.data())->r15;
      break;
    }

    case Header::CPU_TYPE::ARM64:
    {
      if (state_.size() < sizeof(details::arm_thread_state64_t)) {
        return entry;
      }
      entry = reinterpret_cast<const details::arm_thread_state64_t*>(state_.data())
                  ->pc;
      break;
    }

    case Header::CPU_TYPE::POWERPC:
    {
      if (state_.size() < sizeof(details::ppc_thread_state_t)) {
        return entry;
      }
      entry = from_big_endian(
          reinterpret_cast<const details::ppc_thread_state_t*>(state_.data())->srr0
      );
      break;
    }

    case Header::CPU_TYPE::POWERPC64:
    {
      if (state_.size() < sizeof(details::ppc_thread_state64_t)) {
        return entry;
      }
      entry = from_big_endian(
          reinterpret_cast<const details::ppc_thread_state64_t*>(state_.data())
              ->srr0
      );
      break;
    }

    default:
    {
      LIEF_ERR("Unknown architecture");
    }
  }
  return entry;
}

void ThreadCommand::accept(Visitor& visitor) const {
  visitor.visit(*this);
}

std::ostream& ThreadCommand::print(std::ostream& os) const {
  LoadCommand::print(os) << '\n';
  os << fmt::format("flavor={:#x}, count={:#x}, pc={:#08x}", flavor(), count(),
                    pc());
  return os;
}


}