/*
 *  Copyright (C) 2005-2018 Team Kodi
 *  This file is part of Kodi - https://kodi.tv
 *
 *  SPDX-License-Identifier: GPL-2.0-or-later
 *  See LICENSES/README.md for more information.
 */

#include "File.h"

namespace XBMCAddon
{
  namespace xbmcvfs
  {
    XbmcCommons::Buffer File::readBytes(unsigned long numBytes)
    {
      DelayedCallGuard dg(languageHook);
      int64_t size = file->GetLength();
      if ((!numBytes || (((int64_t)numBytes) > size)) && (size >= 0))
        numBytes = (unsigned long) size;


      XbmcCommons::Buffer ret(numBytes);

      if (numBytes == 0)
        return ret;

      while(ret.remaining() > 0)
      {
        ssize_t bytesRead = file->Read(ret.curPosition(), ret.remaining());
        if (bytesRead <= 0) // we consider this a failure or a EOF, can't tell which,
        {                   //  return whatever we have already.
          ret.flip();
          return ret;
        }
        ret.forward(bytesRead);
      }
      ret.flip();
      return ret;
    }

    bool File::write(XbmcCommons::Buffer& buffer)
    {
      DelayedCallGuard dg(languageHook);
      while (buffer.remaining() > 0)
      {
        ssize_t bytesWritten = file->Write( buffer.curPosition(), buffer.remaining());
        if (bytesWritten == 0)       // this could be a failure (see HDFile, and XFileUtils) or
                                     //  it could mean something else when a negative number means an error
                                     //  (see CCurlFile). There is no consistency so we can only assume we're
                                     //  done when we get a 0.
          return false;
        else if (bytesWritten < 0)   // But, if we get something less than zero, we KNOW it's an error.
          return false;
        buffer.forward(bytesWritten);// Otherwise, we advance the buffer by the amount written.
      }
      return true;
    }

  }
}