/*=========================================================================

  Program:   ParaView
  Module:    vtkPVFileInformation.cxx

  Copyright (c) Kitware, Inc.
  All rights reserved.
  See Copyright.txt or http://www.paraview.org/HTML/Copyright.html for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
#include "vtkPVFileInformation.h"
#include "vtkPVConfig.h"

#include "vtkClientServerStream.h"
#include "vtkCollection.h"
#include "vtkCollectionIterator.h"
#include "vtkFileSequenceParser.h"
#include "vtkNew.h"
#include "vtkObjectFactory.h"
#include "vtkPVFileInformationHelper.h"
#include "vtkProcessModule.h"
#include "vtkSmartPointer.h"

#if defined(_WIN32)
#define _WIN32_IE 0x0400    // special folder support
#define _WIN32_WINNT 0x0400 // shared folder support
#include <direct.h>         // _getcwd
#include <shlobj.h>         // SHGetFolderPath
#include <string.h>         // for strcasecmp
#include <windows.h>        // FindFirstFile, FindNextFile, FindClose, ...
#define vtkPVServerFileListingGetCWD _getcwd
#else
#include <dirent.h>    // opendir, readdir, closedir
#include <errno.h>     // errno
#include <stdlib.h>    // getenv
#include <string.h>    // strerror
#include <sys/types.h> // DIR, struct dirent
#include <unistd.h>    // access, getcwd
#define vtkPVServerFileListingGetCWD getcwd
#endif
#if defined(__APPLE__)
#include "vtkPVMacFileInformationHelper.h"
#include <vector>
#endif

#include <algorithm>
#include <set>
#include <string>
#include <time.h>
#include <vtksys/RegularExpression.hxx>
#include <vtksys/SystemTools.hxx>

vtkStandardNewMacro(vtkPVFileInformation);

inline void vtkPVFileInformationAddTerminatingSlash(std::string& name)
{
  if (name.size() > 0)
  {
    char last = *(name.end() - 1);
    if (last != '/' && last != '\\')
    {
#if defined(_WIN32)
      name += "\\";
#else
      name += "/";
#endif
    }
  }
}

#if defined(_WIN32)

static std::string WindowsNetworkRoot = "Windows Network";

// assumes native back-slashes
static bool IsUncPath(const std::string& path)
{
  if (path.size() >= 2 && path[0] == '\\' && path[1] == '\\')
  {
    return true;
  }
  return false;
}

static bool IsNetworkPath(const std::string& path)
{
  if (path.compare(0, WindowsNetworkRoot.size(), WindowsNetworkRoot) == 0)
  {
    return true;
  }
  return false;
}

// returns true if path is valid, false otherwise
// returns subdirs, if any

static bool getNetworkSubdirs(
  const std::string& name, DWORD DisplayType, std::vector<std::string>& subdirs)
{
  HANDLE han = 0;
  NETRESOURCEA rc;
  rc.dwScope = RESOURCE_GLOBALNET;
  rc.dwType = RESOURCETYPE_ANY; // TODO, restrict this to disk at server level?
  rc.dwDisplayType = DisplayType;
  rc.dwUsage = RESOURCEUSAGE_CONTAINER;
  if (DisplayType == RESOURCEDISPLAYTYPE_NETWORK)
  {
    rc.dwUsage |= RESOURCEUSAGE_RESERVED; // wonder why this is needed?
  }
  rc.lpLocalName = NULL;
  rc.lpProvider = NULL;
  rc.lpComment = NULL;
  rc.lpRemoteName = const_cast<char*>(name.c_str());

  DWORD ret = WNetOpenEnumA(RESOURCE_GLOBALNET, RESOURCETYPE_ANY, 0, &rc, &han);

  if (NO_ERROR == ret)
  {
    DWORD count = 10;
    NETRESOURCE res[10];
    DWORD bufsize = sizeof(NETRESOURCE) * count;
    do
    {
      ret = WNetEnumResourceA(han, &count, res, &bufsize);
      if (ret == NO_ERROR || ret == ERROR_MORE_DATA)
      {
        for (DWORD i = 0; i < count; i++)
        {
          std::string subdir = res[i].lpRemoteName;
          if (subdir.compare(0, name.size(), name) == 0)
          {
            subdir = subdir.c_str() + name.size() + 1;
          }
          subdirs.push_back(subdir);
        }
      }
    } while (ret == ERROR_MORE_DATA);
  }
  return NO_ERROR == ret;
}

static bool getNetworkSubdirs(const std::string& path, std::vector<std::string>& subdirs, int& type)
{
  if (!IsNetworkPath(path))
  {
    return false;
  }

  // path follows this convention
  // Windows Network\Domain\Server\Share
  // this doesn't return subdirectories of "Share", use normal
  // win32 API for that

  static const int MaxTokens = 4;

  std::vector<vtksys::String> pathtokens;
  pathtokens = vtksys::SystemTools::SplitString(path.c_str() + 1, '\\');

  static DWORD DisplayType[MaxTokens] = { RESOURCEDISPLAYTYPE_NETWORK, RESOURCEDISPLAYTYPE_DOMAIN,
    RESOURCEDISPLAYTYPE_SERVER, RESOURCEDISPLAYTYPE_SHARE };

  int tokenIndex = static_cast<int>(pathtokens.size()) - 1;

  if (tokenIndex >= MaxTokens)
    return false;

  std::string name = pathtokens[tokenIndex];

  if (tokenIndex == 0)
  {
    type = vtkPVFileInformation::NETWORK_DOMAIN;
  }
  else if (tokenIndex == 1)
  {
    type = vtkPVFileInformation::NETWORK_SERVER;
  }
  else if (tokenIndex == 2)
  {
    type = vtkPVFileInformation::NETWORK_SHARE;
    name = "\\\\" + name;
  }

  return getNetworkSubdirs(name, DisplayType[tokenIndex], subdirs);
}

static bool getUncSharesOnServer(const std::string& server, std::vector<std::string>& ret)
{
  return getNetworkSubdirs(std::string("\\\\") + server, RESOURCEDISPLAYTYPE_SERVER, ret);
}

#endif

static int vtkPVFileInformationGetType(const char* path)
{
  int type = vtkPVFileInformation::INVALID;

  std::string realpath = path;

  if (vtksys::SystemTools::FileExists(realpath.c_str()))
  {
    type = vtkPVFileInformation::SINGLE_FILE;
  }
  if (vtksys::SystemTools::FileIsDirectory(realpath.c_str()))
  {
    type = vtkPVFileInformation::DIRECTORY;
  }
#if defined(_WIN32)
  // doing stat on root of devices doesn't work

  // is it the root of a drive?
  if (realpath.size() > 0 && realpath[1] == ':' && realpath.size() == 2 ||
    (realpath.size() == 3 && realpath[2] == '\\'))
  {
    // Path may be drive letter.
    DWORD n = GetLogicalDrives();
    int which = tolower(realpath[0]) - 'a';
    if (n & (1 << which))
    {
      type = vtkPVFileInformation::DRIVE;
    }
  }

  if (IsNetworkPath(realpath))
  {
    // this code doesn't give out anything with
    // "Windows Network\..." unless its a directory.
    // that may change
    std::vector<vtksys::String> pathtokens;
    pathtokens = vtksys::SystemTools::SplitString(realpath.c_str(), '\\');
    if (pathtokens.size() == 1)
    {
      type = vtkPVFileInformation::NETWORK_ROOT;
    }
    else if (pathtokens.size() == 2)
    {
      type = vtkPVFileInformation::NETWORK_DOMAIN;
    }
    else if (pathtokens.size() == 3)
    {
      type = vtkPVFileInformation::NETWORK_SERVER;
    }
    else
    {
      type = vtkPVFileInformation::NETWORK_SHARE;
    }
  }

  // is it the root of a shared folder?
  if (IsUncPath(realpath))
  {
    std::vector<vtksys::String> parts =
      vtksys::SystemTools::SplitString(realpath.c_str() + 2, '\\', true);
    if (parts.empty())
    {
      // global network
      type = vtkPVFileInformation::DIRECTORY;
    }
    else
    {
      std::vector<std::string> shares;
      bool ret = getUncSharesOnServer(parts[0], shares);
      if (parts.size() == 1 && ret)
      {
        // server exists
        type = vtkPVFileInformation::NETWORK_SERVER;
      }
      else if (parts.size() == 2 && ret)
      {
        for (unsigned int i = 0; i < shares.size(); i++)
        {
          if (parts[1] == shares[i])
          {
            // share on server exists
            type = vtkPVFileInformation::DIRECTORY;
            break;
          }
        }
      }
    }
  }
#endif
  return type;
}

#if defined(_WIN32)
static std::string vtkPVFileInformationResolveLink(const std::string& fname, WIN32_FIND_DATA& wfd)
{
  IShellLink* shellLink;
  HRESULT hr;
  char Link[MAX_PATH];
  bool coInit = false;
  std::string result;

  hr = ::CoCreateInstance(
    CLSID_ShellLink, NULL, CLSCTX_INPROC_SERVER, IID_IShellLink, (LPVOID*)&shellLink);
  if (hr == CO_E_NOTINITIALIZED)
  {
    coInit = true;
    ::CoInitialize(NULL);
    hr = ::CoCreateInstance(
      CLSID_ShellLink, NULL, CLSCTX_INPROC_SERVER, IID_IShellLink, (LPVOID*)&shellLink);
  }
  if (SUCCEEDED(hr))
  {
    IPersistFile* ppf;
    hr = shellLink->QueryInterface(IID_IPersistFile, (LPVOID*)&ppf);
    if (SUCCEEDED(hr))
    {
      std::wstring wfname(fname.begin(), fname.end());
      hr = ppf->Load((LPOLESTR)wfname.c_str(), STGM_READ);
      if (SUCCEEDED(hr))
      {
        if (shellLink->GetPath(Link, MAX_PATH, &wfd, SLGP_UNCPRIORITY) == NOERROR)
        {
          result = Link;
        }
        ppf->Release();
      }
    }
    shellLink->Release();
  }
  if (coInit)
  {
    CoUninitialize();
  }

  return result;
}
#endif

std::string MakeAbsolutePath(const std::string& path, const std::string& working_dir)
{
  std::string ret = path;
#if defined(_WIN32)
  if (!IsUncPath(path) && !IsNetworkPath(path))
#endif
  {
    ret = vtksys::SystemTools::CollapseFullPath(path.c_str(), working_dir.c_str());
  }
  return ret;
}

//-----------------------------------------------------------------------------
class vtkPVFileInformationSet : public std::set<vtkSmartPointer<vtkPVFileInformation> >
{
};

//-----------------------------------------------------------------------------
vtkPVFileInformation::vtkPVFileInformation()
{
  this->RootOnly = 1;
  this->Contents = vtkCollection::New();
  this->SequenceParser = vtkFileSequenceParser::New();
  this->Type = INVALID;
  this->Name = NULL;
  this->FullPath = NULL;
  this->FastFileTypeDetection = 0;
  this->Hidden = false;
  this->Extension = NULL;
  this->Size = 0;
#ifdef _WIN32
  this->ModificationTime = _time64(NULL);
#else
  this->ModificationTime = time(NULL);
#endif
}

//-----------------------------------------------------------------------------
vtkPVFileInformation::~vtkPVFileInformation()
{
  this->Contents->Delete();
  this->SequenceParser->Delete();
  this->SetName(NULL);
  this->SetFullPath(NULL);
  this->SetExtension(NULL);
  this->Size = 0;
#ifdef _WIN32
  this->ModificationTime = _time64(NULL);
#else
  this->ModificationTime = time(NULL);
#endif
}

bool vtkPVFileInformation::IsDirectory(int t)
{
  return t == DIRECTORY || t == DIRECTORY_LINK || t == DRIVE || t == NETWORK_ROOT ||
    t == NETWORK_DOMAIN || t == NETWORK_SERVER || t == NETWORK_SHARE;
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::CopyFromObject(vtkObject* object)
{
  this->Initialize();

  vtkPVFileInformationHelper* helper = vtkPVFileInformationHelper::SafeDownCast(object);
  if (!helper)
  {
    vtkErrorMacro("Can collect information only from a vtkPVFileInformationHelper.");
    return;
  }

  if (helper->GetSpecialDirectories())
  {
    this->GetSpecialDirectories();
    return;
  }

  this->FastFileTypeDetection = helper->GetFastFileTypeDetection();

  std::string working_directory = vtksys::SystemTools::GetCurrentWorkingDirectory().c_str();
  if (helper->GetWorkingDirectory() && helper->GetWorkingDirectory()[0])
  {
    working_directory = helper->GetWorkingDirectory();
  }
  std::string lworking_directory = vtkPVFileInformationHelper::Utf8ToLocalWin32(working_directory);

  std::string path = helper->GetPath();
  std::string lpath = vtkPVFileInformationHelper::Utf8ToLocalWin32(path);
  this->SetName(path.c_str());

  if (!vtksys::SystemTools::FileIsFullPath(path))
  {
    lpath = MakeAbsolutePath(lpath, lworking_directory);
  }

  bool isLink = false;

#if defined(_WIN32)
  std::string::size_type idx;
  for (idx = lpath.find('/', 0); idx != std::string::npos; idx = lpath.find('/', idx))
  {
    lpath.replace(idx, 1, 1, '\\');
  }

  int len = static_cast<int>(lpath.size());
  if (len > 4 && lpath.compare(len - 4, 4, ".lnk") == 0)
  {
    WIN32_FIND_DATA data;
    lpath = vtkPVFileInformationResolveLink(lpath, data);
    isLink = true;
  }
#endif

  this->SetFullPath(vtkPVFileInformationHelper::LocalToUtf8Win32(lpath).c_str());

  this->Type = vtkPVFileInformationGetType(lpath.c_str()); // this->FullPath);
  if (isLink && this->Type == SINGLE_FILE)
  {
    this->Type = SINGLE_FILE_LINK;
  }
  else if (isLink && this->Type == DIRECTORY)
  {
    this->Type = DIRECTORY_LINK;
  }

  // determine if this is a hidden directory/file
  this->SetHiddenFlag();

  if (this->IsDirectory(this->Type) && helper->GetDirectoryListing())
  {
// Since we want a directory listing, we now to platform specific listing
// with intelligent pattern matching hee-haa.
#if defined(_WIN32)
    this->GetWindowsDirectoryListing();
#else
    this->GetDirectoryListing();
#endif
  }
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::GetSpecialDirectories()
{
  // FIXME: Use vtkPVLibraryInfo (see paraview/paraview!798) once it's available
  // to get such paths. Hardcoding it for now.
  if (vtkProcessModule* pm = vtkProcessModule::GetProcessModule())
  {
#if defined(_WIN32) || defined(__APPLE__)
    std::string dataPath = pm->GetSelfDir() + "/../data";
#else
    std::string appdir = pm->GetSelfDir();
    ;
    std::string dataPath = vtksys::SystemTools::GetFilenameName(appdir) == "bin"
      ?
      /* w/o shared forwarding */ appdir + "/../share/paraview-" PARAVIEW_VERSION "/data"
      :
      /* w/ shared forwarding  */ appdir + "/../../share/paraview-" PARAVIEW_VERSION "/data";
#endif
    dataPath = vtksys::SystemTools::CollapseFullPath(dataPath);
    if (vtksys::SystemTools::FileIsDirectory(dataPath))
    {
      vtkNew<vtkPVFileInformation> info;
      info->SetFullPath(dataPath.c_str());
      info->SetName("Examples");
      info->Type = DIRECTORY;
      this->Contents->AddItem(info.Get());
    }
  }

#if defined(_WIN32)
  // Return favorite directories ...

  TCHAR szPath[MAX_PATH];
  std::string tmp;

  if (SUCCEEDED(SHGetSpecialFolderPath(NULL, szPath, CSIDL_PERSONAL, false)))
  {
    tmp = szPath;
    vtkSmartPointer<vtkPVFileInformation> info = vtkSmartPointer<vtkPVFileInformation>::New();
    info->SetFullPath(vtkPVFileInformationHelper::LocalToUtf8Win32(tmp).c_str());
    info->SetName("My Documents");
    info->Type = DIRECTORY;
    this->Contents->AddItem(info);
  }

  if (SUCCEEDED(SHGetSpecialFolderPath(NULL, szPath, CSIDL_DESKTOPDIRECTORY, false)))
  {
    tmp = szPath;
    vtkSmartPointer<vtkPVFileInformation> info = vtkSmartPointer<vtkPVFileInformation>::New();
    info->SetFullPath(vtkPVFileInformationHelper::LocalToUtf8Win32(tmp).c_str());
    info->SetName("Desktop");
    info->Type = DIRECTORY;
    this->Contents->AddItem(info);
  }

  if (SUCCEEDED(SHGetSpecialFolderPath(NULL, szPath, CSIDL_FAVORITES, false)))
  {
    tmp = szPath;
    vtkSmartPointer<vtkPVFileInformation> info = vtkSmartPointer<vtkPVFileInformation>::New();
    info->SetFullPath(vtkPVFileInformationHelper::LocalToUtf8Win32(tmp).c_str());
    info->SetName("Favorites");
    info->Type = DIRECTORY;
    this->Contents->AddItem(info);
  }

  // Return drive letters ...
  DWORD n = GetLogicalDrives();
  for (int i = 0; i < sizeof(DWORD) * 8; i++)
  {
    if (n & (1 << i))
    {
      std::string driveLetter;
      driveLetter += 'A' + i;
      driveLetter += ":\\";
      vtkSmartPointer<vtkPVFileInformation> info = vtkSmartPointer<vtkPVFileInformation>::New();
      info->SetFullPath(driveLetter.c_str());
      info->SetName(driveLetter.c_str());
      info->Type = DRIVE;
      this->Contents->AddItem(info);
    }
  }

  vtkSmartPointer<vtkPVFileInformation> info = vtkSmartPointer<vtkPVFileInformation>::New();
  info->SetFullPath(WindowsNetworkRoot.c_str());
  info->SetName("Windows Network");
  info->Type = NETWORK_ROOT;
  this->Contents->AddItem(info);

#else // _WIN32
#if defined(__APPLE__)

  // Add special directories
  vtkNew<vtkPVMacFileInformationHelper> helper;
  vtkSmartPointer<vtkPVFileInformation> info;

  std::string homeDirectory = helper->GetHomeDirectory();
  if (homeDirectory != "")
  {
    // Home directory
    info = vtkSmartPointer<vtkPVFileInformation>::New();
    info->SetFullPath(homeDirectory.c_str());
    info->SetName("Home");
    info->Type = DIRECTORY;
    this->Contents->AddItem(info);

    // Desktop directory
    std::string desktop = helper->GetDesktopDirectory();
    if (desktop.size() > 0)
    {
      info = vtkSmartPointer<vtkPVFileInformation>::New();
      info->SetFullPath(desktop.c_str());
      info->SetName("Desktop");
      info->Type = DIRECTORY;
      this->Contents->AddItem(info);
    }

    // Documents directory
    std::string documents = helper->GetDocumentsDirectory();
    if (documents.size() > 0)
    {
      info = vtkSmartPointer<vtkPVFileInformation>::New();
      info->SetFullPath(documents.c_str());
      info->SetName("Documents");
      info->Type = DIRECTORY;
      this->Contents->AddItem(info);
    }

    // Downloads directory
    std::string downloads = helper->GetDownloadsDirectory();
    if (downloads.size() > 0)
    {
      info = vtkSmartPointer<vtkPVFileInformation>::New();
      info->SetFullPath(downloads.c_str());
      info->SetName("Downloads");
      info->Type = DIRECTORY;
      this->Contents->AddItem(info);
    }
  }

  // Get the mounted volumes
  std::vector<vtkPVMacFileInformationHelper::NamePath> volumes = helper->GetMountedVolumes();
  for (size_t i = 0; i < volumes.size(); ++i)
  {
    std::string name = volumes[i].first;
    std::string path = volumes[i].second;
    info = vtkSmartPointer<vtkPVFileInformation>::New();

    // Filter out "home" and "net".
    if (name == "home" || name == "net")
    {
      continue;
    }

    info->SetFullPath(path.c_str());
    info->SetName(name.c_str());
    info->Type = DRIVE;
    this->Contents->AddItem(info);
  }

#else
  if (const char* home = getenv("HOME"))
  {
    vtkSmartPointer<vtkPVFileInformation> info = vtkSmartPointer<vtkPVFileInformation>::New();
    info->SetFullPath(home);
    info->SetName("Home");
    info->Type = DIRECTORY;
    this->Contents->AddItem(info);
  }
#endif
#endif // !_WIN32
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::GetWindowsDirectoryListing()
{
#if defined(_WIN32)
  vtkPVFileInformationSet info_set;

  std::string lfullPath = vtkPVFileInformationHelper::Utf8ToLocalWin32(this->FullPath);

  if (IsNetworkPath(lfullPath))
  {
    std::vector<std::string> shares;
    int type;
    if (getNetworkSubdirs(this->FullPath, shares, type))
    {
      for (unsigned int i = 0; i < shares.size(); i++)
      {
        vtkPVFileInformation* info = vtkPVFileInformation::New();
        info->SetName(vtkPVFileInformationHelper::LocalToUtf8Win32(shares[i]).c_str());
        std::string fullpath = vtksys::SystemTools::CollapseFullPath(shares[i].c_str(), lfullPath);
        info->SetFullPath(vtkPVFileInformationHelper::LocalToUtf8Win32(fullpath).c_str());
        info->Type = type;
        info->FastFileTypeDetection = this->FastFileTypeDetection;
        info_set.insert(info);
        info->Delete();
      }
    }
    this->OrganizeCollection(info_set);

    for (vtkPVFileInformationSet::iterator iter = info_set.begin(); iter != info_set.end(); ++iter)
    {
      this->Contents->AddItem(*iter);
    }
    return;
  }

  if (IsUncPath(lfullPath))
  {
    bool didListing = false;
    std::vector<vtksys::String> parts =
      vtksys::SystemTools::SplitString(this->FullPath + 2, '\\', true);

    if (parts.size() == 1)
    {
      // get list of all shares on server
      std::vector<std::string> shares;
      if (getUncSharesOnServer(parts[0], shares))
      {
        for (unsigned int i = 0; i < shares.size(); i++)
        {
          vtkPVFileInformation* info = vtkPVFileInformation::New();
          info->SetName(vtkPVFileInformationHelper::LocalToUtf8Win32(shares[i]).c_str());
          std::string fullpath = "\\\\" + parts[0] + "\\" + shares[i];
          info->SetFullPath(vtkPVFileInformationHelper::LocalToUtf8Win32(fullpath).c_str());
          info->Type = NETWORK_SHARE;
          info->FastFileTypeDetection = this->FastFileTypeDetection;
          info_set.insert(info);
          info->Delete();
        }
      }
      didListing = true;
    }

    if (didListing)
    {
      this->OrganizeCollection(info_set);

      for (vtkPVFileInformationSet::iterator iter = info_set.begin(); iter != info_set.end();
           ++iter)
      {
        this->Contents->AddItem(*iter);
      }
      return;
    }
    // fall through for normal file listing that works after shares are
    // known
  }

  // Search for all files in the given directory.
  std::string prefix = lfullPath;
  vtkPVFileInformationAddTerminatingSlash(prefix);
  std::string pattern = prefix;
  pattern += "*";
  WIN32_FIND_DATA data;
  HANDLE handle = FindFirstFile(pattern.c_str(), &data);
  if (handle == INVALID_HANDLE_VALUE)
  {
    LPVOID lpMsgBuf;
    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM, NULL, GetLastError(),
      MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR)&lpMsgBuf, 0, NULL);
    vtkErrorMacro(
      "Error calling FindFirstFile : " << (char*)lpMsgBuf << "\nDirectory: " << prefix.c_str());
    LocalFree(lpMsgBuf);
    return;
  }

  do
  {
    std::string filename = data.cFileName;
    if (filename == "." || filename == "..")
      continue;
    std::string fullpath = prefix + filename;
    size_t len = filename.size();
    bool isLink = false;

    if (len > 4 && strncmp(filename.c_str() + len - 4, ".lnk", 4) == 0)
    {
      fullpath = vtkPVFileInformationResolveLink(fullpath, data);
      filename.resize(filename.size() - 4);
      isLink = true;
    }

    DWORD isdir = data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY;
    DWORD isfile = (data.dwFileAttributes & FILE_ATTRIBUTE_NORMAL) ||
      (!(data.dwFileAttributes & FILE_ATTRIBUTE_SYSTEM) &&
                     !(data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY));

    FileTypes type = isdir ? DIRECTORY : SINGLE_FILE;
    if (isLink)
    {
      type = type == DIRECTORY ? DIRECTORY_LINK : SINGLE_FILE_LINK;
    }

    if (isdir || isfile)
    {
      vtkPVFileInformation* infoD = vtkPVFileInformation::New();
      infoD->SetName(vtkPVFileInformationHelper::LocalToUtf8Win32(filename).c_str());
      infoD->SetFullPath(vtkPVFileInformationHelper::LocalToUtf8Win32(fullpath).c_str());
      infoD->Type = type;
      infoD->FastFileTypeDetection = this->FastFileTypeDetection;
      infoD->SetHiddenFlag(); // needs full path set first

      // Recover status info
      struct _stat64 status;
      int res = _stat64(fullpath.c_str(), &status);
      if (res != -1)
      {
        if (isfile)
        {
          std::string::size_type pos = filename.rfind('.');
          if (pos != std::string::npos)
          {
            std::string ext = filename.substr(pos + 1);
            infoD->SetExtension(ext.c_str());
          }
        }
        infoD->Size = status.st_size;
        infoD->ModificationTime = status.st_mtime;
      }

      info_set.insert(infoD);
      infoD->Delete();
    }

    // Find the next file.
  } while (FindNextFile(handle, &data) != 0);

  if (GetLastError() != ERROR_NO_MORE_FILES)
  {
    LPVOID lpMsgBuf;
    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM, NULL, GetLastError(),
      MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR)&lpMsgBuf, 0, NULL);
    vtkErrorMacro(
      "Error calling FindNextFile : " << (char*)lpMsgBuf << "\nDirectory: " << prefix.c_str());
    LocalFree(lpMsgBuf);
  }

  if (!FindClose(handle))
  {
    vtkErrorMacro("Error calling FindClose.");
  }

  this->OrganizeCollection(info_set);

  for (vtkPVFileInformationSet::iterator iter = info_set.begin(); iter != info_set.end(); ++iter)
  {
    this->Contents->AddItem(*iter);
  }

#else
  vtkErrorMacro("GetWindowsDirectoryListing cannot be called on non-Windows systems.");
#endif
}

/* There is a problem with the Portland compiler, large file
support and glibc/Linux system headers:
             http://www.pgroup.com/userforum/viewtopic.php?
             p=1992&sid=f16167f51964f1a68fe5041b8eb213b6
*/
#if defined(__PGI) && defined(__USE_FILE_OFFSET64)
#define dirent dirent64
#endif

//-----------------------------------------------------------------------------
void vtkPVFileInformation::GetDirectoryListing()
{
#if defined(_WIN32)

  vtkErrorMacro("GetDirectoryListing() cannot be called on Windows systems.");
  return;

#else

  vtkPVFileInformationSet info_set;
  std::string prefix = this->FullPath;
  vtkPVFileInformationAddTerminatingSlash(prefix);

  // Open the directory and make sure it exists.
  DIR* dir = opendir(this->FullPath);
  if (!dir)
  {
    // Could add check of errno here.
    return;
  }

  // Loop through the directory listing.
  while (const dirent* d = readdir(dir))
  {
    // Skip the special directory entries.
    if (strcmp(d->d_name, ".") == 0 || strcmp(d->d_name, "..") == 0)
    {
      continue;
    }
    vtkPVFileInformation* info = vtkPVFileInformation::New();
    info->SetName(d->d_name);
    info->SetFullPath((prefix + d->d_name).c_str());
    info->Type = INVALID;
    info->SetHiddenFlag();

    // Recover status info
    vtksys::SystemTools::Stat_t status;
    int res = vtksys::SystemTools::Stat(info->FullPath, &status);
    if (res != -1)
    {
      if (!S_ISDIR(status.st_mode))
      {
        std::string::size_type pos = std::string(d->d_name).rfind('.');
        if (pos != std::string::npos)
        {
          std::string ext = std::string(d->d_name).substr(pos + 1);
          info->SetExtension(ext.c_str());
        }
      }
      info->Size = status.st_size;
      info->ModificationTime = status.st_mtime;
    }
// fix to bug #09452 such that directories with trailing names can be
// shown in the file dialog
#if defined(__SVR4) && defined(__sun)
    if (res != -1 && status.st_mode & S_IFDIR)
    {
      info->Type = DIRECTORY;
    }
#else
    if (d->d_type & DT_DIR)
    {
      info->Type = DIRECTORY;
    }
#endif

    info->FastFileTypeDetection = this->FastFileTypeDetection;
    info_set.insert(info);
    info->Delete();
  }
  closedir(dir);

  this->OrganizeCollection(info_set);

  // Now we detect the file types for items.
  // We dissolve any groups that contain non-file items.

  for (vtkPVFileInformationSet::iterator iter = info_set.begin(); iter != info_set.end(); ++iter)
  {
    vtkPVFileInformation* obj = (*iter);
    if (obj->DetectType())
    {
      this->Contents->AddItem(obj);
    }
    else
    {
      // Add children to contents.
      for (int cc = 0; cc < obj->Contents->GetNumberOfItems(); cc++)
      {
        vtkPVFileInformation* child =
          vtkPVFileInformation::SafeDownCast(obj->Contents->GetItemAsObject(cc));
        if (child->DetectType())
        {
          this->Contents->AddItem(child);
        }
      }
    }
  }
#endif
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::SetHiddenFlag()
{
#if defined(_WIN32)
  if (!this->FullPath)
  {
    this->Hidden = false;
    return;
  }
  // LPCSTR fp = this->FullPath;
  DWORD flags =
    GetFileAttributes(vtkPVFileInformationHelper::Utf8ToLocalWin32(this->FullPath).c_str());
  this->Hidden = (flags & FILE_ATTRIBUTE_HIDDEN) ? true : false;
#else
  if (!this->Name)
  {
    this->Hidden = false;
    return;
  }
  this->Hidden = (this->Name[0] == '.') ? true : false;
#endif
}

//-----------------------------------------------------------------------------
bool vtkPVFileInformation::DetectType()
{
  if (this->Type == FILE_GROUP)
  {
    vtkSmartPointer<vtkCollectionIterator> iter;
    iter.TakeReference(this->Contents->NewIterator());
    for (iter->InitTraversal(); !iter->IsDoneWithTraversal(); iter->GoToNextItem())
    {
      vtkPVFileInformation* child = vtkPVFileInformation::SafeDownCast(iter->GetCurrentObject());
      if (!child->DetectType() || child->Type != SINGLE_FILE)
      {
        return false;
      }
      if (this->FastFileTypeDetection)
      {
        // Assume all children are same as this child.
        for (; !iter->IsDoneWithTraversal(); iter->GoToNextItem())
        {
          vtkPVFileInformation* child2 =
            vtkPVFileInformation::SafeDownCast(iter->GetCurrentObject());
          child2->Type = child->Type;
        }
        break;
      }
    }
    return true;
  }
  else if (this->Type == INVALID)
  {
    if (vtksys::SystemTools::FileExists(this->FullPath))
    {
      this->Type = (vtksys::SystemTools::FileIsDirectory(this->FullPath)) ? DIRECTORY : SINGLE_FILE;
      return true;
    }
    return false;
  }
  return true;
}

struct vtkPVFileInformation::vtkInfo
{
  typedef std::map<int, vtkSmartPointer<vtkPVFileInformation> > ChildrenType;
  vtkSmartPointer<vtkPVFileInformation> Group;
  ChildrenType Children;
};

//-----------------------------------------------------------------------------
void vtkPVFileInformation::OrganizeCollection(vtkPVFileInformationSet& info_set)
{
  typedef std::map<std::string, vtkInfo> MapOfStringToInfo;
  MapOfStringToInfo fileGroups;

  std::string prefix = this->FullPath;
  vtkPVFileInformationAddTerminatingSlash(prefix);

  for (vtkPVFileInformationSet::iterator iter = info_set.begin(); iter != info_set.end();)
  {
    vtkPVFileInformation* obj = *iter;

    if (obj->Type != FILE_GROUP && !IsDirectory(obj->Type))
    {
      bool match = false;

      match = this->SequenceParser->ParseFileSequence(obj->GetName());

      if (match)
      {
        std::string groupName = this->SequenceParser->GetSequenceName();
        int groupIndex = this->SequenceParser->GetSequenceIndex();

        MapOfStringToInfo::iterator iter2 = fileGroups.find(groupName);
        vtkPVFileInformation* group = 0;
        if (iter2 == fileGroups.end())
        {
          group = vtkPVFileInformation::New();
          group->SetName(groupName.c_str());
          group->SetFullPath((prefix + groupName).c_str());
          group->Type = FILE_GROUP;
          // the group inherits the hidden flag of the first item in the group
          group->Hidden = obj->Hidden;
          group->FastFileTypeDetection = this->FastFileTypeDetection;
          // fileGroups[groupName] = group;
          vtkInfo info;
          info.Group = group;
          fileGroups[groupName] = info;
          group->Delete();

          iter2 = fileGroups.find(groupName);
        }

        iter2->second.Children[groupIndex] = obj;
        vtkPVFileInformationSet::iterator prev_iter = iter++;
        info_set.erase(prev_iter);
        continue;
      }
    }
    ++iter;
  }

  // Now scan through all created groups and dissolve trivial groups
  // i.e. groups with single entries. Add all other groups to the
  // results.
  for (MapOfStringToInfo::iterator iter2 = fileGroups.begin(); iter2 != fileGroups.end(); ++iter2)
  {
    vtkInfo& info = iter2->second;
    vtkPVFileInformation* group = info.Group;
    if (info.Children.size() > 1)
    {
      vtkInfo::ChildrenType::iterator childIter = info.Children.begin();
      for (; childIter != info.Children.end(); ++childIter)
      {
        group->Contents->AddItem(childIter->second.GetPointer());
      }
      // Build group children.
      info_set.insert(group);
    }
    else
    {
      vtkInfo::ChildrenType::iterator childIter = info.Children.begin();
      for (; childIter != info.Children.end(); ++childIter)
      {
        info_set.insert(childIter->second.GetPointer());
      }
    }
  }
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::CopyToStream(vtkClientServerStream* stream)
{
  *stream << vtkClientServerStream::Reply << this->Name << this->FullPath << this->Type
          << this->Hidden << this->Contents->GetNumberOfItems() << this->Extension << this->Size
          << this->ModificationTime;

  vtkSmartPointer<vtkCollectionIterator> iter;
  iter.TakeReference(this->Contents->NewIterator());
  for (iter->InitTraversal(); !iter->IsDoneWithTraversal(); iter->GoToNextItem())
  {
    vtkClientServerStream childStream;
    vtkPVFileInformation* child = vtkPVFileInformation::SafeDownCast(iter->GetCurrentObject());
    child->CopyToStream(&childStream);
    *stream << childStream;
  }
  *stream << vtkClientServerStream::End;
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::CopyFromStream(const vtkClientServerStream* css)
{
  this->Initialize();
  const char* temp = 0;
  if (!css->GetArgument(0, 0, &temp))
  {
    vtkErrorMacro("Error parsing Name.");
    return;
  }
  this->SetName(temp);

  if (!css->GetArgument(0, 1, &temp))
  {
    vtkErrorMacro("Error parsing FullPath.");
    return;
  }
  this->SetFullPath(temp);

  if (!css->GetArgument(0, 2, &this->Type))
  {
    vtkErrorMacro("Error parsing Type.");
    return;
  }

  if (!css->GetArgument(0, 3, &this->Hidden))
  {
    vtkErrorMacro("Error parsing Hidden.");
    return;
  }

  int num_of_children = 0;
  if (!css->GetArgument(0, 4, &num_of_children))
  {
    vtkErrorMacro("Error parsing Number of children.");
    return;
  }
  if (!css->GetArgument(0, 5, &temp))
  {
    vtkErrorMacro("Error parsing File extension.");
    return;
  }
  this->SetExtension(temp);
  if (!css->GetArgument(0, 6, &this->Size))
  {
    vtkErrorMacro("Error parsing File extension.");
    return;
  }
  if (!css->GetArgument(0, 7, &this->ModificationTime))
  {
    vtkErrorMacro("Error parsing File extension.");
    return;
  }
  for (int cc = 0; cc < num_of_children; cc++)
  {
    vtkPVFileInformation* child = vtkPVFileInformation::New();
    vtkClientServerStream childStream;
    if (!css->GetArgument(0, 8 + cc, &childStream))
    {
      vtkErrorMacro("Error parsing child #" << cc);
      return;
    }
    child->CopyFromStream(&childStream);
    this->Contents->AddItem(child);
    child->Delete();
  }
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::Initialize()
{
  this->SetName(0);
  this->SetFullPath(0);
  this->Type = INVALID;
  this->Hidden = false;
  this->Contents->RemoveAllItems();
  this->SetExtension(0);
  this->Size = 0;
#ifdef _WIN32
  this->ModificationTime = _time64(NULL);
#else
  this->ModificationTime = time(NULL);
#endif
}

//-----------------------------------------------------------------------------
void vtkPVFileInformation::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os, indent);
  os << indent << "Name: " << (this->Name ? this->Name : "(null)") << endl;
  os << indent << "FullPath: " << (this->FullPath ? this->FullPath : "(null)") << endl;
  os << indent << "Type: ";
  switch (this->Type)
  {
    case INVALID:
      os << "INVALID" << endl;
      break;

    case SINGLE_FILE:
      os << "SINGLE_FILE" << endl;
      break;

    case DIRECTORY:
      os << "DIRECTORY" << endl;
      break;

    case FILE_GROUP:
      os << "FILE_GROUP" << endl;
  }
  os << indent << "Hidden: " << this->Hidden << endl;
  os << indent << "FastFileTypeDetection: " << this->FastFileTypeDetection << endl;

  for (int cc = 0; cc < this->Contents->GetNumberOfItems(); cc++)
  {
    os << endl;
    this->Contents->GetItemAsObject(cc)->PrintSelf(os, indent.GetNextIndent());
  }
}
