/*
Copyright (C) 2012 Sebastian Herbord. All rights reserved.

This file is part of Mod Organizer.

Mod Organizer 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.

Mod Organizer 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 Mod Organizer.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "util.h"
#include "windows_error.h"
#include "mainwindow.h"
#include "env.h"
#include <log.h>
#include <usvfs.h>
#include <usvfs_version.h>

namespace MOShared
{

bool FileExists(const std::string &filename)
{
  DWORD dwAttrib = ::GetFileAttributesA(filename.c_str());

  return (dwAttrib != INVALID_FILE_ATTRIBUTES);
}

bool FileExists(const std::wstring &filename)
{
  DWORD dwAttrib = ::GetFileAttributesW(filename.c_str());

  return (dwAttrib != INVALID_FILE_ATTRIBUTES);
}

bool FileExists(const std::wstring &searchPath, const std::wstring &filename)
{
  std::wstringstream stream;
  stream << searchPath << "\\" << filename;
  return FileExists(stream.str());
}

std::string ToString(const std::wstring &source, bool utf8)
{
  std::string result;
  if (source.length() > 0) {
    UINT codepage = CP_UTF8;
    if (!utf8) {
      codepage = AreFileApisANSI() ? GetACP() : GetOEMCP();
    }
    int sizeRequired = ::WideCharToMultiByte(codepage, 0, &source[0], -1, nullptr, 0, nullptr, nullptr);
    if (sizeRequired == 0) {
      throw windows_error("failed to convert string to multibyte");
    }
    // the size returned by WideCharToMultiByte contains zero termination IF -1 is specified for the length.
    // we don't want that \0 in the string because then the length field would be wrong. Because madness
    result.resize(sizeRequired - 1, '\0');
    ::WideCharToMultiByte(codepage, 0, &source[0], (int)source.size(), &result[0], sizeRequired, nullptr, nullptr);
  }

  return result;
}

std::wstring ToWString(const std::string &source, bool utf8)
{
  std::wstring result;
  if (source.length() > 0) {
    UINT codepage = CP_UTF8;
    if (!utf8) {
      codepage = AreFileApisANSI() ? GetACP() : GetOEMCP();
    }
    int sizeRequired
        = ::MultiByteToWideChar(codepage, 0, source.c_str(),
                                static_cast<int>(source.length()), nullptr, 0);
    if (sizeRequired == 0) {
      throw windows_error("failed to convert string to wide character");
    }
    result.resize(sizeRequired, L'\0');
    ::MultiByteToWideChar(codepage, 0, source.c_str(),
                          static_cast<int>(source.length()), &result[0],
                          sizeRequired);
  }

  return result;
}

static std::locale loc("");
static auto locToLowerW = [] (wchar_t in) -> wchar_t {
  return std::tolower(in, loc);
};

static auto locToLower = [] (char in) -> char {
  return std::tolower(in, loc);
};

std::string &ToLower(std::string &text)
{
  //std::transform(text.begin(), text.end(), text.begin(), locToLower);
  CharLowerBuffA(const_cast<CHAR *>(text.c_str()), static_cast<DWORD>(text.size()));
  return text;
}

std::string ToLower(const std::string &text)
{
  std::string result(text);
  //std::transform(result.begin(), result.end(), result.begin(), locToLower);
  CharLowerBuffA(const_cast<CHAR *>(result.c_str()), static_cast<DWORD>(result.size()));
  return result;
}

std::wstring &ToLower(std::wstring &text)
{
  //std::transform(text.begin(), text.end(), text.begin(), locToLowerW);
  CharLowerBuffW(const_cast<WCHAR *>(text.c_str()), static_cast<DWORD>(text.size()));
  return text;
}

std::wstring ToLower(const std::wstring &text)
{
  std::wstring result(text);
  //std::transform(result.begin(), result.end(), result.begin(), locToLowerW);
  CharLowerBuffW(const_cast<WCHAR *>(result.c_str()), static_cast<DWORD>(result.size()));
  return result;
}

bool CaseInsenstiveComparePred(wchar_t lhs, wchar_t rhs)
{
  return std::tolower(lhs, loc) == std::tolower(rhs, loc);
}

bool CaseInsensitiveEqual(const std::wstring &lhs, const std::wstring &rhs)
{
  return (lhs.length() == rhs.length())
      && std::equal(lhs.begin(), lhs.end(),
                    rhs.begin(),
                    [] (wchar_t lhs, wchar_t rhs) -> bool {
                      return std::tolower(lhs, loc) == std::tolower(rhs, loc);
                    });
}

VS_FIXEDFILEINFO GetFileVersion(const std::wstring &fileName)
{
  DWORD handle = 0UL;
  DWORD size = ::GetFileVersionInfoSizeW(fileName.c_str(), &handle);
  if (size == 0) {
    throw windows_error("failed to determine file version info size");
  }

  boost::scoped_array<char> buffer(new char[size]);
  try {
    handle = 0UL;
    if (!::GetFileVersionInfoW(fileName.c_str(), handle, size, buffer.get())) {
      throw windows_error("failed to determine file version info");
    }

    void *versionInfoPtr = nullptr;
    UINT versionInfoLength = 0;
    if (!::VerQueryValue(buffer.get(), L"\\", &versionInfoPtr, &versionInfoLength)) {
      throw windows_error("failed to determine file version");
    }

    VS_FIXEDFILEINFO result = *(VS_FIXEDFILEINFO*)versionInfoPtr;
    return result;
  } catch (...) {
    throw;
  }
}

std::wstring GetFileVersionString(const std::wstring &fileName)
{
  DWORD handle = 0UL;
  DWORD size = ::GetFileVersionInfoSizeW(fileName.c_str(), &handle);
  if (size == 0) {
    throw windows_error("failed to determine file version info size");
  }

  boost::scoped_array<char> buffer(new char[size]);
  try {
    handle = 0UL;
    if (!::GetFileVersionInfoW(fileName.c_str(), handle, size, buffer.get())) {
      throw windows_error("failed to determine file version info");
    }

    LPVOID strBuffer = nullptr;
    UINT strLength = 0;
    if (!::VerQueryValue(buffer.get(), L"\\StringFileInfo\\040904B0\\ProductVersion", &strBuffer, &strLength)) {
      throw windows_error("failed to determine file version");
    }

    return std::wstring((LPCTSTR)strBuffer);
  }
  catch (...) {
    throw;
  }
}

MOBase::VersionInfo createVersionInfo()
{
  VS_FIXEDFILEINFO version = GetFileVersion(QApplication::applicationFilePath().toStdWString());

  if (version.dwFileFlags & VS_FF_PRERELEASE)
  {
    // Pre-release builds need annotating
    QString versionString = QString::fromStdWString(GetFileVersionString(QApplication::applicationFilePath().toStdWString()));

    // The pre-release flag can be set without the string specifying what type of pre-release
    bool noLetters = true;
    for (QChar character : versionString)
    {
      if (character.isLetter())
      {
        noLetters = false;
        break;
      }
    }

    if (noLetters)
    {
      // Default to pre-alpha when release type is unspecified
      return MOBase::VersionInfo(version.dwFileVersionMS >> 16,
                                 version.dwFileVersionMS & 0xFFFF,
                                 version.dwFileVersionLS >> 16,
                                 version.dwFileVersionLS & 0xFFFF,
                                 MOBase::VersionInfo::RELEASE_PREALPHA);
    }
    else
    {
      // Trust the string to make sense
      return MOBase::VersionInfo(versionString);
    }
  }
  else
  {
    // Non-pre-release builds just need their version numbers reading
    return MOBase::VersionInfo(version.dwFileVersionMS >> 16,
                               version.dwFileVersionMS & 0xFFFF,
                               version.dwFileVersionLS >> 16,
                               version.dwFileVersionLS & 0xFFFF);
  }
}

QString getUsvfsDLLVersion()
{
  // once 2.2.2 is released, this can be changed to call USVFSVersionString()
  // directly; until then, using GetProcAddress() allows for mixing up devbuilds
  // and usvfs dlls

  using USVFSVersionStringType = const char* WINAPI ();

  QString s;

  const auto m = ::LoadLibraryW(L"usvfs_x64.dll");

  if (m) {
    auto* f = reinterpret_cast<USVFSVersionStringType*>(
      ::GetProcAddress(m, "USVFSVersionString"));

    if (f) {
      s = f();
    }

    ::FreeLibrary(m);
  }

  if (s.isEmpty()) {
    s = "?";
  }

  return s;
}

QString getUsvfsVersionString()
{
  const QString dll = getUsvfsDLLVersion();
  const QString header = USVFS_VERSION_STRING;

  QString usvfsVersion;

  if (dll == header) {
    return dll;
  } else {
    return "dll is " + dll + ", compiled against " + header;
  }
}

void SetThisThreadName(const QString& s)
{
  using SetThreadDescriptionType = HRESULT (
    HANDLE hThread,
    PCWSTR lpThreadDescription
  );

  static SetThreadDescriptionType* SetThreadDescription = [] {
    SetThreadDescriptionType* p = nullptr;

    env::LibraryPtr kernel32(LoadLibraryW(L"kernel32.dll"));
    if (!kernel32) {
      return p;
    }

    p = reinterpret_cast<SetThreadDescriptionType*>(
      GetProcAddress(kernel32.get(), "SetThreadDescription"));

    return p;
  }();

  if (SetThreadDescription) {
    SetThreadDescription(GetCurrentThread(), s.toStdWString().c_str());
  }
}

} // namespace MOShared


TimeThis::TimeThis(QString what)
  : m_what(std::move(what)), m_start(Clock::now())
{
}

TimeThis::~TimeThis()
{
  using namespace std::chrono;

  const auto end = Clock::now();
  const auto d = duration_cast<milliseconds>(end - m_start).count();

  if (m_what.isEmpty()) {
    MOBase::log::debug("{} ms", d);
  } else {
    MOBase::log::debug("{} {} ms", m_what, d);
  }
}


static bool g_exiting = false;
static bool g_canClose = false;

MainWindow* findMainWindow()
{
  for (auto* tl : qApp->topLevelWidgets()) {
    if (auto* mw=dynamic_cast<MainWindow*>(tl)) {
      return mw;
    }
  }

  return nullptr;
}

bool ExitModOrganizer(ExitFlags e)
{
  if (g_exiting) {
    return true;
  }

  g_exiting = true;
  MOBase::Guard g([&]{ g_exiting = false; });

  if (!e.testFlag(Exit::Force)) {
    if (auto* mw=findMainWindow()) {
      if (!mw->canExit()) {
        return false;
      }
    }
  }

  g_canClose = true;

  const int code = (e.testFlag(Exit::Restart) ? RestartExitCode : 0);
  qApp->exit(code);

  return true;
}

bool ModOrganizerCanCloseNow()
{
  return g_canClose;
}

bool ModOrganizerExiting()
{
  return g_exiting;
}

void ResetExitFlag()
{
  g_exiting = false;
}