/*============================================================================
  CMake - Cross Platform Makefile Generator
  Copyright 2000-2010 Kitware, Inc., Insight Software Consortium

  Distributed under the OSI-approved BSD License (the "License");
  see accompanying file Copyright.txt for details.

  This software is distributed WITHOUT ANY WARRANTY; without even the
  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the License for more information.
============================================================================*/
#include "cmArchiveWrite.h"

#include "cmSystemTools.h"
#include <cmsys/ios/iostream>
#include <cmsys/Directory.hxx>
#include <cmsys/FStream.hxx>
#include <cm_libarchive.h>

//----------------------------------------------------------------------------
static std::string cm_archive_error_string(struct archive* a)
{
  const char* e = archive_error_string(a);
  return e? e : "unknown error";
}

//----------------------------------------------------------------------------
class cmArchiveWrite::Entry
{
  struct archive_entry* Object;
public:
  Entry(): Object(archive_entry_new()) {}
  ~Entry() { archive_entry_free(this->Object); }
  operator struct archive_entry*() { return this->Object; }
};

//----------------------------------------------------------------------------
struct cmArchiveWrite::Callback
{
  // archive_write_callback
  static __LA_SSIZE_T Write(struct archive*, void *cd,
                            const void *b, size_t n)
    {
    cmArchiveWrite* self = static_cast<cmArchiveWrite*>(cd);
    if(self->Stream.write(static_cast<const char*>(b),
                          static_cast<cmsys_ios::streamsize>(n)))
      {
      return static_cast<__LA_SSIZE_T>(n);
      }
    else
      {
      return static_cast<__LA_SSIZE_T>(-1);
      }
    }
};

//----------------------------------------------------------------------------
cmArchiveWrite::cmArchiveWrite(std::ostream& os, Compress c, Type t):
  Stream(os),
  Archive(archive_write_new()),
  Disk(archive_read_disk_new()),
  Verbose(false)
{
  switch (c)
    {
    case CompressNone:
      if(archive_write_set_compression_none(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_compression_none: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
      break;
    case CompressCompress:
      if(archive_write_set_compression_compress(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_compression_compress: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
      break;
    case CompressGZip:
      if(archive_write_set_compression_gzip(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_compression_gzip: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
      break;
    case CompressBZip2:
      if(archive_write_set_compression_bzip2(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_compression_bzip2: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
      break;
    case CompressLZMA:
      if(archive_write_set_compression_lzma(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_compression_lzma: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
      break;
    case CompressXZ:
      if(archive_write_set_compression_xz(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_compression_xz: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
      break;
    };
#if !defined(_WIN32) || defined(__CYGWIN__)
  if (archive_read_disk_set_standard_lookup(this->Disk) != ARCHIVE_OK)
    {
    this->Error = "archive_read_disk_set_standard_lookup: ";
    this->Error += cm_archive_error_string(this->Archive);
    return;;
    }
#endif
  switch (t)
    {
    case TypeZIP:
      if(archive_write_set_format_zip(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_format_zip: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
      break;
    case TypeTAR:
      if(archive_write_set_format_pax_restricted(this->Archive) != ARCHIVE_OK)
        {
        this->Error = "archive_write_set_format_pax_restricted: ";
        this->Error += cm_archive_error_string(this->Archive);
        return;
        }
    break;
    }

  // do not pad the last block!!
  if (archive_write_set_bytes_in_last_block(this->Archive, 1))
    {
    this->Error = "archive_write_set_bytes_in_last_block: ";
    this->Error += cm_archive_error_string(this->Archive);
    return;
    }

  if(archive_write_open(
       this->Archive, this, 0,
       reinterpret_cast<archive_write_callback*>(&Callback::Write),
       0) != ARCHIVE_OK)
    {
    this->Error = "archive_write_open: ";
    this->Error += cm_archive_error_string(this->Archive);
    return;
    }
}

//----------------------------------------------------------------------------
cmArchiveWrite::~cmArchiveWrite()
{
  archive_read_finish(this->Disk);
  archive_write_finish(this->Archive);
}

//----------------------------------------------------------------------------
bool cmArchiveWrite::Add(std::string path, size_t skip, const char* prefix)
{
  if(this->Okay())
    {
    if(!path.empty() && path[path.size()-1] == '/')
      {
      path.erase(path.size()-1);
      }
    this->AddPath(path.c_str(), skip, prefix);
    }
  return this->Okay();
}

//----------------------------------------------------------------------------
bool cmArchiveWrite::AddPath(const char* path,
                             size_t skip, const char* prefix)
{
  if(!this->AddFile(path, skip, prefix))
    {
    return false;
    }
  if(!cmSystemTools::FileIsDirectory(path) ||
    cmSystemTools::FileIsSymlink(path))
    {
    return true;
    }
  cmsys::Directory d;
  if(d.Load(path))
    {
    std::string next = path;
    next += "/";
    std::string::size_type end = next.size();
    unsigned long n = d.GetNumberOfFiles();
    for(unsigned long i = 0; i < n; ++i)
      {
      const char* file = d.GetFile(i);
      if(strcmp(file, ".") != 0 && strcmp(file, "..") != 0)
        {
        next.erase(end);
        next += file;
        if(!this->AddPath(next.c_str(), skip, prefix))
          {
          return false;
          }
        }
      }
    }
  return true;
}

//----------------------------------------------------------------------------
bool cmArchiveWrite::AddFile(const char* file,
                             size_t skip, const char* prefix)
{
  // Skip the file if we have no name for it.  This may happen on a
  // top-level directory, which does not need to be included anyway.
  if(skip >= strlen(file))
    {
    return true;
    }
  const char* out = file + skip;

  // Meta-data.
  std::string dest = prefix? prefix : "";
  dest += out;
  if(this->Verbose)
    {
    std::cout << dest << "\n";
    }
  Entry e;
  archive_entry_copy_sourcepath(e, file);
  archive_entry_set_pathname(e, dest.c_str());
  if(archive_read_disk_entry_from_file(this->Disk, e, -1, 0) != ARCHIVE_OK)
    {
    this->Error = "archive_read_disk_entry_from_file: ";
    this->Error += cm_archive_error_string(this->Disk);
    return false;
    }
  // Clear acl and xattr fields not useful for distribution.
  archive_entry_acl_clear(e);
  archive_entry_xattr_clear(e);
  archive_entry_set_fflags(e, 0, 0);
  if(archive_write_header(this->Archive, e) != ARCHIVE_OK)
    {
    this->Error = "archive_write_header: ";
    this->Error += cm_archive_error_string(this->Archive);
    return false;
    }

  // do not copy content of symlink
  if (!archive_entry_symlink(e))
    {
    // Content.
    if(size_t size = static_cast<size_t>(archive_entry_size(e)))
      {
      return this->AddData(file, size);
      }
    }
  return true;
}

//----------------------------------------------------------------------------
bool cmArchiveWrite::AddData(const char* file, size_t size)
{
  cmsys::ifstream fin(file, std::ios::in | cmsys_ios_binary);
  if(!fin)
    {
    this->Error = "Error opening \"";
    this->Error += file;
    this->Error += "\": ";
    this->Error += cmSystemTools::GetLastSystemError();
    return false;
    }

  char buffer[16384];
  size_t nleft = size;
  while(nleft > 0)
    {
    typedef cmsys_ios::streamsize ssize_type;
    size_t const nnext = nleft > sizeof(buffer)? sizeof(buffer) : nleft;
    ssize_type const nnext_s = static_cast<ssize_type>(nnext);
    fin.read(buffer, nnext_s);
    // Some stream libraries (older HPUX) return failure at end of
    // file on the last read even if some data were read.  Check
    // gcount instead of trusting the stream error status.
    if(static_cast<size_t>(fin.gcount()) != nnext)
      {
      break;
      }
    if(archive_write_data(this->Archive, buffer, nnext) != nnext_s)
      {
      this->Error = "archive_write_data: ";
      this->Error += cm_archive_error_string(this->Archive);
      return false;
      }
    nleft -= nnext;
    }
  if(nleft > 0)
    {
    this->Error = "Error reading \"";
    this->Error += file;
    this->Error += "\": ";
    this->Error += cmSystemTools::GetLastSystemError();
    return false;
    }
  return true;
}