// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
// Mobius Forensic Toolkit
// Copyright (C) 2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019,2020,2021,2022,2023 Eduardo Aguiar
//
// This program 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 2, or (at your option) any later
// version.
//
// This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
#include "filesystem.h"
#include "filesystem_impl_null.h"
#include <mobius/core/resource.h>

namespace mobius
{
namespace vfs
{
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Default constructor
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
filesystem::filesystem ()
 : impl_ (std::make_shared <filesystem_impl_null> ())
{
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Constructor
//! \param reader Reader object
//! \param offset Offset from the beginning of the stream
//! \param type Filesystem type (default = "autodetect")
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
filesystem::filesystem (
  const mobius::io::reader& reader,
  std::uint64_t offset,
  const std::string& type
)
{
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  // Detect filesystem type, if type == "autodetect"
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  if (type == "autodetect")
    {
      for (const auto& resource : mobius::core::get_resources ("filesystem"))
        {
          auto fs_resource = resource.get_value <filesystem_resource_type> ();

          if (fs_resource.is_instance (reader, offset))
            {
              impl_ = fs_resource.build (reader, offset);
              break;
            }
        }
    }

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  // Otherwise, lookup implementation according to type
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  else
    {
      auto resource = mobius::core::get_resource ("filesystem." + type);

      if (resource)
        {
          auto fs_resource = resource.get_value <filesystem_resource_type> ();
          impl_ = fs_resource.build (reader, offset);
        }
    }

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  // If filesystem is not detected, create null instance
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  if (!impl_)
    impl_ = std::make_shared <filesystem_impl_null> ();
}

} // namespace vfs
} // namespace mobius
