/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying

   file LICENSE.rst or https://cmake.org/licensing for details.  */

#include "cmFileTimes.h"

#include <utility>

#include <cm/memory>

#include "cmsys/Status.hxx"

#include "cm_sys_stat.h"

#if defined(_WIN32)

#  include <windows.h>

#  include "cmSystemTools.h"

#else

#  include <cerrno>

#  include <utime.h>

#endif

#if defined(_WIN32) &&                                                        \

  (defined(_MSC_VER) || defined(__WATCOMC__) || defined(__MINGW32__))

#  include <io.h>

#endif

#ifdef _WIN32

class cmFileTimes::WindowsHandle

{

public:

  WindowsHandle(HANDLE h)

    : handle_(h)

  {

  }

  ~WindowsHandle()

  {

    if (this->handle_ != INVALID_HANDLE_VALUE) {

      CloseHandle(this->handle_);

    }

  }

  explicit operator bool() const

  {

    return this->handle_ != INVALID_HANDLE_VALUE;

  }

  bool operator!() const { return this->handle_ == INVALID_HANDLE_VALUE; }

  operator HANDLE() const { return this->handle_; }

private:

  HANDLE handle_;

};

#endif

class cmFileTimes::Times

{

public:

#if defined(_WIN32) && !defined(__CYGWIN__)

  FILETIME timeCreation;

  FILETIME timeLastAccess;

  FILETIME timeLastWrite;

#else

  struct utimbuf timeBuf;

#endif

};

cmFileTimes::cmFileTimes() = default;

cmFileTimes::cmFileTimes(std::string const& fileName)

{

  this->Load(fileName);

}

cmFileTimes::~cmFileTimes() = default;

cmsys::Status cmFileTimes::Load(std::string const& fileName)

{

  std::unique_ptr<Times> ptr;

  if (this->IsValid()) {

    // Invalidate this and reuse times

    ptr.swap(this->times);

  } else {

    ptr = cm::make_unique<Times>();

  }

#if defined(_WIN32) && !defined(__CYGWIN__)

  cmFileTimes::WindowsHandle handle =

    CreateFileW(cmSystemTools::ConvertToWindowsExtendedPath(fileName).c_str(),

                GENERIC_READ, FILE_SHARE_READ, 0, OPEN_EXISTING,

                FILE_FLAG_BACKUP_SEMANTICS, 0);

  if (!handle) {

    return cmsys::Status::Windows_GetLastError();

  }

  if (!GetFileTime(handle, &ptr->timeCreation, &ptr->timeLastAccess,

                   &ptr->timeLastWrite)) {

    return cmsys::Status::Windows_GetLastError();

  }

#else

  struct stat st;

  if (stat(fileName.c_str(), &st) < 0) {

    return cmsys::Status::POSIX_errno();

  }

  ptr->timeBuf.actime = st.st_atime;

  ptr->timeBuf.modtime = st.st_mtime;

#endif

  // Accept times

  this->times = std::move(ptr);

  return cmsys::Status::Success();

}

cmsys::Status cmFileTimes::Store(std::string const& fileName) const

{

  if (!this->IsValid()) {

    return cmsys::Status::POSIX(EINVAL);

  }

#if defined(_WIN32) && !defined(__CYGWIN__)

  cmFileTimes::WindowsHandle handle = CreateFileW(

    cmSystemTools::ConvertToWindowsExtendedPath(fileName).c_str(),

    FILE_WRITE_ATTRIBUTES, 0, 0, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, 0);

  if (!handle) {

    return cmsys::Status::Windows_GetLastError();

  }

  if (SetFileTime(handle, &this->times->timeCreation,

                  &this->times->timeLastAccess,

                  &this->times->timeLastWrite) == 0) {

    return cmsys::Status::Windows_GetLastError();

  }

#else

  if (utime(fileName.c_str(), &this->times->timeBuf) < 0) {

    return cmsys::Status::POSIX_errno();

  }

#endif

  return cmsys::Status::Success();

}

cmsys::Status cmFileTimes::Copy(std::string const& fromFile,

                                std::string const& toFile)

{

  cmFileTimes fileTimes;

  cmsys::Status load_status = fileTimes.Load(fromFile);

  if (!load_status) {

    return load_status;

  }

  return fileTimes.Store(toFile);

}