// VerCtrl.cpp

#include "StdAfx.h"

#include "../../../Common/StringToInt.h"

#include "../../../Windows/FileName.h"
#include "../../../Windows/FileFind.h"

#include "App.h"
#include "RegistryUtils.h"
#include "OverwriteDialog.h"

#include "resource.h"

using namespace NWindows;
using namespace NFile;
using namespace NFind;
using namespace NDir;

static FString ConvertPath_to_Ctrl(const FString &path)
{
  FString s = path;
  s.Replace(FChar(':'), FChar('_'));
  return s;
}

struct CFileDataInfo
{
  CByteBuffer Data;
  BY_HANDLE_FILE_INFORMATION Info;
  bool IsOpen;

  CFileDataInfo(): IsOpen (false) {}
  UInt64 GetSize() const { return (((UInt64)Info.nFileSizeHigh) << 32) + Info.nFileSizeLow; }
  bool Read(const FString &path);
};


bool CFileDataInfo::Read(const FString &path)
{
  IsOpen = false;
  NIO::CInFile file;
  if (!file.Open(path))
    return false;
  if (!file.GetFileInformation(&Info))
    return false;

  const UInt64 size = GetSize();
  const size_t size2 = (size_t)size;
  if (size2 != size || size2 > (1 << 28))
  {
    SetLastError(1);
    return false;
  }

  Data.Alloc(size2);

  size_t processedSize;
  if (!file.ReadFull(Data, size2, processedSize))
    return false;
  if (processedSize != size2)
  {
    SetLastError(1);
    return false;
  }
  IsOpen = true;
  return true;
}


static bool CreateComplexDir_for_File(const FString &path)
{
  FString resDirPrefix;
  FString resFileName;
  if (!GetFullPathAndSplit(path, resDirPrefix, resFileName))
    return false;
  return CreateComplexDir(resDirPrefix);
}


static bool ParseNumberString(const FString &s, UInt32 &number)
{
  const FChar *end;
  UInt64 result = ConvertStringToUInt64(s, &end);
  if (*end != 0 || s.IsEmpty() || result > (UInt32)0x7FFFFFFF)
    return false;
  number = (UInt32)result;
  return true;
}


static void WriteFile(const FString &path, bool createAlways, const CFileDataInfo &fdi, const CPanel &panel)
{
  NIO::COutFile outFile;
  if (!outFile.Create(path, createAlways)) // (createAlways = false) means CREATE_NEW
  {
    panel.MessageBox_LastError();
    return;
  }
  UInt32 processedSize;
  if (!outFile.Write(fdi.Data, (UInt32)fdi.Data.Size(), processedSize))
  {
    panel.MessageBox_LastError();
    return;
  }
  if (processedSize != fdi.Data.Size())
  {
    panel.MessageBox_Error(L"Write error");
    return;
  }
  if (!outFile.SetTime(
      &fdi.Info.ftCreationTime,
      &fdi.Info.ftLastAccessTime,
      &fdi.Info.ftLastWriteTime))
  {
    panel.MessageBox_LastError();
    return;
  }

  if (!SetFileAttrib(path, fdi.Info.dwFileAttributes))
  {
    panel.MessageBox_LastError();
    return;
  }
}


static UInt64 FILETIME_to_UInt64(const FILETIME &ft)
{
  return ft.dwLowDateTime | ((UInt64)ft.dwHighDateTime << 32);
}

static void UInt64_TO_FILETIME(UInt64 v, FILETIME &ft)
{
  ft.dwLowDateTime = (DWORD)v;
  ft.dwHighDateTime = (DWORD)(v >> 32);
}


void CApp::VerCtrl(unsigned id)
{
  const CPanel &panel = GetFocusedPanel();
  
  if (!panel.Is_IO_FS_Folder())
  {
    panel.MessageBox_Error_UnsupportOperation();
    return;
  }

  CRecordVector<UInt32> indices;
  panel.GetSelectedItemsIndices(indices);

  if (indices.Size() != 1)
  {
    // panel.MessageBox_Error_UnsupportOperation();
    return;
  }

  const FString path = us2fs(panel.GetItemFullPath(indices[0]));

  UString vercPath;
  ReadReg_VerCtrlPath(vercPath);
  if (vercPath.IsEmpty())
    return;
  NName::NormalizeDirPathPrefix(vercPath);

  FString dirPrefix;
  FString fileName;
  if (!GetFullPathAndSplit(path, dirPrefix, fileName))
  {
    panel.MessageBox_LastError();
    return;
  }

  const FString dirPrefix2 = us2fs(vercPath) + ConvertPath_to_Ctrl(dirPrefix);
  const FString path2 = dirPrefix2 + fileName;

  bool sameTime = false;
  bool sameData = false;
  bool areIdentical = false;

  CFileDataInfo fdi, fdi2;
  if (!fdi.Read(path))
  {
    panel.MessageBox_LastError();
    return;
  }

  if (fdi2.Read(path2))
  {
    sameData = (fdi.Data == fdi2.Data);
    sameTime = (CompareFileTime(&fdi.Info.ftLastWriteTime, &fdi2.Info.ftLastWriteTime) == 0);
    areIdentical = (sameData && sameTime);
  }

  const bool isReadOnly = NAttributes::IsReadOnly(fdi.Info.dwFileAttributes);

  if (id == IDM_VER_EDIT)
  {
    if (!isReadOnly)
    {
      panel.MessageBox_Error(L"File is not read-only");
      return;
    }
    
    if (!areIdentical)
    {
      if (fdi2.IsOpen)
      {
        NFind::CEnumerator enumerator;
        FString d2 = dirPrefix2;
        d2 += "_7vc";
        d2.Add_PathSepar();
        d2 += fileName;
        d2.Add_PathSepar();
        enumerator.SetDirPrefix(d2);
        NFind::CDirEntry fi;
        Int32 maxVal = -1;
        while (enumerator.Next(fi))
        {
          UInt32 val;
          if (!ParseNumberString(fi.Name, val))
            continue;
          if ((Int32)val > maxVal)
            maxVal = val;
        }

        UInt32 next = (UInt32)maxVal + 1;
        if (maxVal < 0)
        {
          next = 1;
          if (!::CreateComplexDir_for_File(path2))
          {
            panel.MessageBox_LastError();
            return;
          }
        }

        // we rename old file2 to some name;
        FString path_num = d2;
        {
          AString t;
          t.Add_UInt32((UInt32)next);
          while (t.Len() < 3)
            t.InsertAtFront('0');
          path_num += t;
        }

        if (maxVal < 0)
        {
          if (!::CreateComplexDir_for_File(path_num))
          {
            panel.MessageBox_LastError();
            return;
          }
        }

        if (!NDir::MyMoveFile(path2, path_num))
        {
          panel.MessageBox_LastError();
          return;
        }
      }
      else
      {
        if (!::CreateComplexDir_for_File(path2))
        {
          panel.MessageBox_LastError();
          return;
        }
      }
      /*
      if (!::CopyFile(fs2fas(path), fs2fas(path2), TRUE))
      {
        panel.MessageBox_LastError();
        return;
      }
      */
      WriteFile(path2,
          false,  // (createAlways = false) means CREATE_NEW
          fdi, panel);
    }
      
    if (!SetFileAttrib(path, fdi.Info.dwFileAttributes & ~(DWORD)FILE_ATTRIBUTE_READONLY))
    {
      panel.MessageBox_LastError();
      return;
    }

    return;
  }
  
  if (isReadOnly)
  {
    panel.MessageBox_Error(L"File is read-only");
    return;
  }

  if (id == IDM_VER_COMMIT)
  {
    if (sameData)
    {
      if (!sameTime)
      {
        panel.MessageBox_Error(
          L"Same data, but different timestamps.\n"
          L"Use `Revert` to recover timestamp.");
        return;
      }
    }

    const UInt64 timeStampOriginal = FILETIME_to_UInt64(fdi.Info.ftLastWriteTime);
    UInt64 timeStamp2 = 0;
    if (fdi2.IsOpen)
      timeStamp2 = FILETIME_to_UInt64(fdi2.Info.ftLastWriteTime);

    if (timeStampOriginal > timeStamp2)
    {
      const UInt64 k_Ntfs_prec = 10000000;
      UInt64 timeStamp = timeStampOriginal;
      const UInt32 k_precs[] = { 60 * 60, 60, 2, 1 };
      for (unsigned i = 0; i < ARRAY_SIZE(k_precs); i++)
      {
        timeStamp = timeStampOriginal;
        const UInt64 prec = k_Ntfs_prec * k_precs[i];
        // timeStamp += prec - 1; // for rounding up
        timeStamp /= prec;
        timeStamp *= prec;
        if (timeStamp > timeStamp2)
          break;
      }

      if (timeStamp != timeStampOriginal
          && timeStamp > timeStamp2)
      {
        FILETIME mTime;
        UInt64_TO_FILETIME(timeStamp, mTime);
        // NDir::SetFileAttrib(path, 0);
        {
          NIO::COutFile outFile;
          if (!outFile.Open(path, OPEN_EXISTING))
          {
            panel.MessageBox_LastError();
            return;
            // if (::GetLastError() != ERROR_SUCCESS)
            // throw "open error";
          }
          else
          {
            const UInt64 cTime = FILETIME_to_UInt64(fdi.Info.ftCreationTime);
            if (cTime > timeStamp)
              outFile.SetTime(&mTime, NULL, &mTime);
            else
              outFile.SetMTime(&mTime);
          }
        }
      }
    }

    if (!SetFileAttrib(path, fdi.Info.dwFileAttributes | FILE_ATTRIBUTE_READONLY))
    {
      panel.MessageBox_LastError();
      return;
    }
    return;
  }

  if (id == IDM_VER_REVERT)
  {
    if (!fdi2.IsOpen)
    {
      panel.MessageBox_Error(L"No file to revert");
      return;
    }
    if (!sameData || !sameTime)
    {
      if (!sameData)
      {
        /*
        UString m;
        m = "Are you sure you want to revert file ?";
        m.Add_LF();
        m += path;
        if (::MessageBoxW(panel.GetParent(), m, L"Version Control: File Revert", MB_OKCANCEL | MB_ICONQUESTION) != IDOK)
          return;
        */
        COverwriteDialog dialog;
        
        dialog.OldFileInfo.SetTime(&fdi.Info.ftLastWriteTime);
        dialog.OldFileInfo.SetSize(fdi.GetSize());
        dialog.OldFileInfo.Name = fs2us(path);
        
        dialog.NewFileInfo.SetTime(&fdi2.Info.ftLastWriteTime);
        dialog.NewFileInfo.SetSize(fdi2.GetSize());
        dialog.NewFileInfo.Name = fs2us(path2);

        dialog.ShowExtraButtons = false;
        dialog.DefaultButton_is_NO = true;
        
        INT_PTR writeAnswer = dialog.Create(panel.GetParent());
        
        if (writeAnswer != IDYES)
          return;
      }
      
      WriteFile(path,
          true,  // (createAlways = true) means CREATE_ALWAYS
          fdi2, panel);
    }
    else
    {
      if (!SetFileAttrib(path, fdi2.Info.dwFileAttributes | FILE_ATTRIBUTE_READONLY))
      {
        panel.MessageBox_LastError();
        return;
      }
    }
    return;
  }

  // if (id == IDM_VER_DIFF)
  {
    if (!fdi2.IsOpen)
      return;
    DiffFiles(fs2us(path2), fs2us(path));
  }
}
