// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
// 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 "file_impl.h"
#include "folder_impl.h"
#include "reader_impl.h"
#include "writer_impl.h"
#include "path.h"
#include "uri.h"
#include <mobius/exception.inc>
#include <mobius/exception_posix.inc>
#include <mobius/system/user.h>
#include <mobius/system/group.h>
#include <climits>
#include <stdexcept>
#include <unistd.h>
#include <sys/stat.h>

namespace mobius::io::local
{
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Initialize object
//! \param path File path
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::file_impl (const std::string& path)
  : path_ (path), given_path_ (path)
{
  if (path_.empty ())
    throw std::invalid_argument (MOBIUS_EXCEPTION_MSG ("invalid path"));
  
  mobius::io::path p (path_);
  name_ = p.get_filename ();
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get file name
//! \return File name
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
std::string
file_impl::get_name () const
{
  return name_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Check if URL file exists
//! \return true/false
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
bool
file_impl::exists () const
{
  if (!is_stat_loaded_)
    _load_stat ();

  return exists_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Check if file is deleted
//! \return true/false
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
bool
file_impl::is_deleted () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return false;  // local files are never deleted
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Check if file is reallocated
//! \return true/false
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
bool
file_impl::is_reallocated () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return false;  // local files are never reallocated
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Check if file is hidden
//! \return true/false
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
bool
file_impl::is_hidden () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return !name_.empty () && name_[0] == '.';
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get short file name
//! \return Short file name
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
std::string
file_impl::get_short_name () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return std::string (); // local files don't have short names
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get file inode
//! \return Inode
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::inode_type
file_impl::get_inode () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return inode_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get file size
//! \return Size in bytes
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::size_type
file_impl::get_size () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return size_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get file type
//! \return File type
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::type
file_impl::get_type () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return type_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief get file owner's user id
//! \return user ID
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::user_id_type
file_impl::get_user_id () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return user_id_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief get file owner's user name
//! \return user name
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
std::string
file_impl::get_user_name () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return user_name_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief get file group ID
//! \return group ID
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::group_id_type
file_impl::get_group_id () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return group_id_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief get file owner's group name
//! \return group name
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
std::string
file_impl::get_group_name () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return group_name_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief get file access permissions
//! \return permission mask
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::permission_type
file_impl::get_permissions () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return permissions_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get last access timestamp
//! \return Last file access date/time
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
mobius::datetime::datetime
file_impl::get_access_time () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return access_time_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get last metadata modification timestamp
//! \return Last file metadata modification date/time
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
mobius::datetime::datetime
file_impl::get_modification_time () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return modification_time_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get last metadata modification timestamp
//! \return Last file metadata modification date/time
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
mobius::datetime::datetime
file_impl::get_metadata_time () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return metadata_time_;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get creation time
//! \return Creation date/time
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
mobius::datetime::datetime
file_impl::get_creation_time () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return mobius::datetime::datetime (); // local files don't have creation time
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get deletion time
//! \return Deletion date/time
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
mobius::datetime::datetime
file_impl::get_deletion_time () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return mobius::datetime::datetime (); // local files don't have deletion time
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get backup time
//! \return Backup date/time
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
mobius::datetime::datetime
file_impl::get_backup_time () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return mobius::datetime::datetime (); // local files don't have backup time
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get parent folder
//! \return Parent folder
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::folder_type
file_impl::get_parent () const
{
  mobius::io::path path (path_);

  return std::make_shared <folder_impl> (path.get_dirname ());
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Reload file info
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
void
file_impl::reload ()
{
  is_stat_loaded_ = false;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Remove file
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
void
file_impl::remove ()
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));
  
  if (::remove (path_.c_str ()) == -1)
    throw std::runtime_error (MOBIUS_EXCEPTION_POSIX);
  
  is_stat_loaded_ = false;  // force reload of attributes
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Rename file
//! \param filename New filename
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
void
file_impl::rename (const std::string& filename)
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  // create new path
  mobius::io::path old_path (path_);
  mobius::io::path new_path = old_path.get_sibling_by_name (filename);
  
  // rename file
  if (::rename (path_.c_str (), new_path.get_value ().c_str ()) == -1)
    throw std::runtime_error (MOBIUS_EXCEPTION_POSIX);

  // update attributes
  path_ = new_path.get_value ();
  name_ = filename;
  is_stat_loaded_ = false;  // force reload of attributes
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Move file
//! \param f File implementation pointer
//! \return <b>true</b> if file has been moved, <b>false</b> otherwise
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
bool
file_impl::move (file_type impl)
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));
  
  // if destination file impl is also local, use rename function
  auto pimpl = std::dynamic_pointer_cast <file_impl> (impl);

  if (pimpl)
    {
      if (::rename (path_.c_str (), pimpl->path_.c_str ()) == -1)
        throw std::runtime_error (MOBIUS_EXCEPTION_POSIX);
      
      return true;
    }
    
  return false;
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Create a reader for file
//! \return Pointer to a new created reader
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::reader_type
file_impl::new_reader () const
{
  if (!exists ())
    throw std::runtime_error (MOBIUS_EXCEPTION_MSG ("file does not exist"));

  return std::make_shared <reader_impl> (path_);
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Create a writer for file
//! \param overwite true/false to wipe file content
//! \return Pointer to a new created writer
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
file_impl::writer_type
file_impl::new_writer (bool overwrite) const
{
  return std::make_shared <writer_impl> (path_, overwrite);
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief load metadata calling POSIX stat function
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
void
file_impl::_load_stat () const
{
  if (is_stat_loaded_)
    return;

  struct stat st;

  if (lstat (path_.c_str (), &st))   // error
    {
      exists_ = false;

      if (errno != ENOENT && errno != ENOTDIR)
        throw std::runtime_error (MOBIUS_EXCEPTION_POSIX);
    }

  else
    {
      exists_ = true;

      inode_ = st.st_ino;
      size_ = st.st_size;
      user_id_ = st.st_uid;
      group_id_ = st.st_gid;
      permissions_ = st.st_mode & 0777;
      access_time_ = mobius::datetime::new_datetime_from_unix_timestamp (st.st_atime);
      modification_time_ = mobius::datetime::new_datetime_from_unix_timestamp (st.st_mtime);
      metadata_time_ = mobius::datetime::new_datetime_from_unix_timestamp (st.st_ctime);

      // get user name
      mobius::system::user user (user_id_);
      if (user)
        user_name_ = user.get_name ();

      // get group name
      mobius::system::group group (group_id_);
      if (group)
        group_name_ = group.get_name ();

      // handle file according to type
      auto t = st.st_mode & S_IFMT;
      
      if (t == S_IFBLK)
        type_ = type::block_device;
      
      else if (t == S_IFCHR)
        type_ = type::char_device;
      
      else if (t == S_IFIFO)
        type_ = type::fifo;
      
      else if (t == S_IFLNK)
        {
          type_ = type::symlink;

          /*char buffer[PATH_MAX];
          auto rc = readlink (path_.c_str (), buffer, PATH_MAX);
          
          if (rc != -1)
            metadata_.set ("linkpath", std::string (buffer, rc));*/
        }

      else if (t == S_IFREG)
        type_ = type::regular;
      
      else if (t == S_IFSOCK)
        type_ = type::socket;
      
      else
        type_ = type::none;
    }

  is_stat_loaded_ = true;
}

} // namespace mobius::io::local
