#ifndef PvlTokenizer_h
#define PvlTokenizer_h
/**
 * @file
 * $Revision: 1.5 $
 * $Date: 2010/01/09 02:09:23 $
 *
 *   Unless noted otherwise, the portions of Isis written by the USGS are public
 *   domain. See individual third-party library and package descriptions for
 *   intellectual property information,user agreements, and related information.
 *
 *   Although Isis has been used by the USGS, no warranty, expressed or implied,
 *   is made by the USGS as to the accuracy and functioning of such software
 *   and related material nor shall the fact of distribution constitute any such
 *   warranty, and no responsibility is assumed by the USGS in connection
 *   therewith.
 *
 *   For additional information, launch
 *   $ISISROOT/doc//documents/Disclaimers/Disclaimers.html in a browser or see
 *   the Privacy &amp; Disclaimers page on the Isis website,
 *   http://isis.astrogeology.usgs.gov, and the USGS privacy and disclaimers on
 *   http://www.usgs.gov/privacy.html.
 */

#include <iostream>
#include "PvlToken.h"

#include <QString>

namespace Isis {
  /**
   * @brief Construct Token list from a stream
   *
   * This class tokenizes a stream. That is, it will take a stream, from a file
   * or a string, and break the contents of the stream into keyword-value pairs.
   * Examples of such are PDS labels, the standard Isis command line, and VICAR
   * labels. Note that this does not validate the stream to ensure it is of PDS-
   * or VICAR-type. It simply creates a list of keyword-value pairs which can be
   * parsed by another object. The ruleset for tokenizing is straightforward.
   * Consider SPACECRAFT=MARS_GLOBAL_SURVEYOR. The keyword would be SPACECRAFT
   * and the value would be MARS_GLOBAL_SURVEYOR. Other valid examples include:
   * LINES=5, FOCAL_LENGTH=12.4, INSTRUMENT="CAMERA_A", LIST=(0,1,5), and
   * DOGS=("LAB","PUG","BULL"). The later examples, are considered arrays and
   * therefore, will have multiple values associated with the keyword. Comments
   * are allowed in the stream and are indicated by either "#" or "/ *" as the
   * first character on the line.
   *
   * @ingroup Parsing
   *
   * @author 2002-02-15 Jeff Anderson
   *
   * @internal
   *  @history 2003-02-25 Stuart Sides - Modified the way END is checked for. It
   *                                     was not working for embedded labels.
   *
   *  @history 2003-05-16 Stuart Sides - Modified schema from astrogeology...
   *                                     isis.astrogeology...
   *
   *  @history 2003-05-28 Stuart Sides - Modified so single quotes work the same
   *                                     as double quotes
   *
   *  @history 2003-10-28 Jeff Anderson - Fixed bug in order to allow for
   *                                      whitespace inside of arrays of strings
   *
   *  @history 2004-01-22 Jeff Anderson - Removed single quotes when the occur as
   *                                      delimeters inside of array keywords.
   *
   *  @history 2005-02-16 Jeff Anderson - Modified parsing of comma separated
   *                                      lists to not remove parens or squiggly
   *                                      brackets.
   *
   *  @history 2005-02-18 Elizabeth Ribelin - Modified file to support Doxygen
   *                                          documentation
   *
   *  @history 2006-05-31 Elizabeth Miller - Fixed bug in Load method when a
   *                                         keyword is loaded without a value
   *
   *  @todo 2005-02-14 Jeff Anderson - finish class documentation and add coded
   *                                   and implementation examples
   *
   *  @history 2007-04-13 Stuart Sides - Fixed bug where quoted strings broken
   *                                     over more than two lines were not being
   *                                     read correctly.
   *
   *  @history 2009-03-13 Steven Lambright - Inline comments now correctly
   *           correlate to the keywords before them on the same line.
   *
   *  @history 2010-01-08 Eric Hyer - PvlTokenizer.cpp used EOF without including
   *                                  fstream, breaking this class on recent
   *                                  compilers (I added #include <fstream>).
   */
  class PvlTokenizer {

    protected:
      std::vector<Isis::PvlToken> tokens; /**<The array of Tokens parse out of
                                              the stream*/


      QString ReadComment(std::istream &stream);
      QString ReadToken(std::istream &stream);
      bool SkipWhiteSpace(std::istream &stream);
      QString ReadToSingleQuote(std::istream &stream);
      QString ReadToDoubleQuote(std::istream &stream);
      QString ReadToParen(std::istream &stream);
      QString ReadToBrace(std::istream &stream);
      void ParseCommaList(Isis::PvlToken &t, const QString &cl);
      void ValidateCharacter(int c);

    public:
      PvlTokenizer();
      ~PvlTokenizer();

      void Load(std::istream &stream, const QString &terminator = "END");
      void Clear();

      std::vector<Isis::PvlToken> & GetTokenList();
  };
};

#endif
