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

Program:   Visualization Toolkit
Module:    vtkASCIITextCodec.cxx

Copyright (c)
All rights reserved.
See Copyright.txt or http://www.kitware.com/Copyright.htm 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.

=========================================================================*/
/*-------------------------------------------------------------------------
  Copyright 2010 Sandia Corporation.
  Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
  the U.S. Government retains certain rights in this software.
-------------------------------------------------------------------------*/

#include <vtkASCIITextCodec.h>

#include <vtkObjectFactory.h>
#include <vtkTextCodecFactory.h>

#include <stdexcept>

vtkStandardNewMacro(vtkASCIITextCodec);

const char* vtkASCIITextCodec::Name() {return "US-ASCII" ;}

bool vtkASCIITextCodec::CanHandle(const char* NameStr)
{
  if (0 == strcmp(NameStr, "US-ASCII") || 0 == strcmp(NameStr, "ASCII"))
    return true ;
  else
    return false ;
}

bool vtkASCIITextCodec::IsValid(istream& InputStream)
{
  bool returnBool = true ;

  // get the position of the stream so we can restore it when we are done
  istream::pos_type StreamPos = InputStream.tellg() ;

  // check the code points for non-ascii characters
  while (!InputStream.eof())
    {
    vtkTypeUInt32 CodePoint = InputStream.get() ;

    if(!InputStream.eof() && CodePoint > 0x7f)
      {
      returnBool = false ;
      break ;
      }
    }

  // reset the stream
  InputStream.clear() ;
  InputStream.seekg(StreamPos) ;

  return returnBool ;
}


void vtkASCIITextCodec::ToUnicode(istream& InputStream,
                                  vtkTextCodec::OutputIterator& output)
{
  while (!InputStream.eof())
    {
    vtkTypeUInt32 CodePoint = InputStream.get();

    if(!InputStream.eof())
      {
      if (CodePoint > 0x7f)
        throw std::runtime_error("Detected a character that isn't valid US-ASCII.");

      *output++ = CodePoint;
      }
    }
}


vtkUnicodeString::value_type vtkASCIITextCodec::NextUnicode(istream& InputStream)
{
  vtkTypeUInt32 CodePoint = InputStream.get();

  if (!InputStream.eof())
    {
    if(CodePoint > 0x7f)
      throw std::runtime_error("Detected a character that isn't valid US-ASCII.");

    return CodePoint ;
    }
  else
    return 0 ;
}

vtkASCIITextCodec::vtkASCIITextCodec() : vtkTextCodec()
{
}


vtkASCIITextCodec::~vtkASCIITextCodec()
{
}


void vtkASCIITextCodec::PrintSelf(ostream& os, vtkIndent indent)
{
  os << indent << "vtkASCIITextCodec (" << this << ") \n" ;
  indent = indent.GetNextIndent();
  this->Superclass::PrintSelf(os, indent.GetNextIndent()) ;
}