RhodeCode

	    }

	  } else if (section == "attributes" && !attributes_done) {

	    if (_attributes_caption.empty() || _attributes_caption == caption) {

	      readAttributes();

	      attributes_done = true;

	    }

	  } else {

	    if (extra_sections.find(section) != extra_sections.end()) {

	      std::ostringstream msg;

	      msg << "Multiple occurence of section " << section;

	      throw DataFormatError(msg.str().c_str());

	    }

	    Sections::iterator it = _sections.find(section);

	    if (it != _sections.end()) {

	      extra_sections.insert(section);

	      it->second->process(*_is, line_num);

	    }

	    readLine();

	    skipSection();

	  }

	} catch (DataFormatError& error) {

	  error.line(line_num);

	  throw;

	}	

      }

      if (!nodes_done) {

	throw DataFormatError("Section @nodes not found");

      }

      if (!edges_done) {

	throw DataFormatError("Section @edges not found");

      }

      if (!attributes_done && !_attributes.empty()) {

	throw DataFormatError("Section @attributes not found");

      }

    }

    /// @}

  };

  /// \relates GraphReader

  template <typename Graph>

  GraphReader<Graph> graphReader(std::istream& is, Graph& graph) {

    GraphReader<Graph> tmp(is, graph);

    return tmp;

  }

  /// \relates GraphReader

  template <typename Graph>

  GraphReader<Graph> graphReader(const std::string& fn, 

				       Graph& graph) {

    GraphReader<Graph> tmp(fn, graph);

    return tmp;

  }

  /// \relates GraphReader

  template <typename Graph>

  GraphReader<Graph> graphReader(const char* fn, Graph& graph) {

    GraphReader<Graph> tmp(fn, graph);

    return tmp;

  }

  /// \ingroup lemon_io

  ///

  /// \brief Reader for the contents of the \ref lgf-format "LGF" file 

  ///

  /// This class can be used to read the sections, the map names and

  /// the attributes from a file. Usually, the Lemon programs know

  /// that, which type of graph, which maps and which attributes

  /// should be read from a file, but in general tools (like glemon)

  /// the contents of an LGF file should be guessed somehow. This class

  /// reads the graph and stores the appropriate information for

  /// reading the graph.

  ///

  ///\code LgfContents contents("graph.lgf"); 

  /// contents.run();

  ///

  /// // does it contain any node section and arc section

  /// if (contents.nodeSectionNum() == 0 || contents.arcSectionNum()) {

  ///   std::cerr << "Failure, cannot find graph" << std::endl;

  ///   return -1;

  /// }

  /// std::cout << "The name of the default node section : " 

  ///           << contents.nodeSection(0) << std::endl;

  /// std::cout << "The number of the arc maps : " 

  ///           << contents.arcMaps(0).size() << std::endl;

  /// std::cout << "The name of second arc map : " 

  ///           << contents.arcMaps(0)[1] << std::endl;

  ///\endcode

  class LgfContents {    

  private:

    std::istream* _is;

    bool local_is;

    std::vector<std::string> _node_sections;

    std::vector<std::string> _edge_sections;

    std::vector<std::string> _attribute_sections;

    std::vector<std::string> _extra_sections;

    std::vector<bool> _arc_sections;

    std::vector<std::vector<std::string> > _node_maps;

    std::vector<std::vector<std::string> > _edge_maps;

    std::vector<std::vector<std::string> > _attributes;

    int line_num;

    std::istringstream line;

  public:

    /// \brief Constructor

    ///

    /// Construct an \e LGF contents reader, which reads from the given

    /// input stream.

    LgfContents(std::istream& is) 

      : _is(&is), local_is(false) {}

    /// \brief Constructor

    ///

    /// Construct an \e LGF contents reader, which reads from the given

    /// file.

    LgfContents(const std::string& fn) 

      : _is(new std::ifstream(fn.c_str())), local_is(true) {}

    /// \brief Constructor

    ///

    /// Construct an \e LGF contents reader, which reads from the given

    /// file.

    LgfContents(const char* fn)

      : _is(new std::ifstream(fn)), local_is(true) {}

    /// \brief Copy constructor

    ///

    /// The copy constructor transfers all data from the other reader,

    /// therefore the copied reader will not be usable more. 

    LgfContents(LgfContents& other)

      : _is(other._is), local_is(other.local_is) {

      other._is = 0;

      other.local_is = false;

      _node_sections.swap(other._node_sections);

      _edge_sections.swap(other._edge_sections);

      _attribute_sections.swap(other._attribute_sections);

      _extra_sections.swap(other._extra_sections);

      _arc_sections.swap(other._arc_sections);

      _node_maps.swap(other._node_maps);

      _edge_maps.swap(other._edge_maps);

      _attributes.swap(other._attributes);

    }

    /// \brief Destructor

    ~LgfContents() {

      if (local_is) delete _is;

    }

    /// \name Node sections

    /// @{

    /// \brief Gives back the number of node sections in the file.

    ///

    /// Gives back the number of node sections in the file.

    int nodeSectionNum() const {

      return _node_sections.size();

    }

    /// \brief Returns the section name at the given position. 

    ///

    /// Returns the section name at the given position. 

    const std::string& nodeSection(int i) const {

      return _node_sections[i];

    }

    /// \brief Gives back the node maps for the given section.

    ///

    /// Gives back the node maps for the given section.

    const std::vector<std::string>& nodeMaps(int i) const {

      return _node_maps[i];

    }

    /// @}

    /// @{

    ///

    int arcSectionNum() const {

      return _edge_sections.size();

    }

    /// \brief Returns the section name at the given position. 

    ///

    /// Returns the section name at the given position. 

    const std::string& arcSection(int i) const {

      return _edge_sections[i];

    }

    ///

    const std::vector<std::string>& arcMaps(int i) const {

      return _edge_maps[i];

    }

    /// @}

    /// @{

    ///

    int edgeSectionNum() const {

      return _edge_sections.size();

    }

    /// \brief Returns the section name at the given position. 

    ///

    /// Returns the section name at the given position. 

    const std::string& edgeSection(int i) const {

      return _edge_sections[i];

    }

    /// \brief Gives back the edge maps for the given section.

    ///

    /// Gives back the edge maps for the given section.

    const std::vector<std::string>& edgeMaps(int i) const {

      return _edge_maps[i];

    }

    /// @}

    /// \name Attribute sections   

    /// @{

    /// \brief Gives back the number of attribute sections in the file.

    ///

    /// Gives back the number of attribute sections in the file.

    int attributeSectionNum() const {

      return _attribute_sections.size();

    }

    /// \brief Returns the section name at the given position. 

    ///

    /// Returns the section name at the given position. 

    const std::string& attributeSection(int i) const {

      return _attribute_sections[i];

    }

    /// \brief Gives back the attributes for the given section.

    ///

    /// Gives back the attributes for the given section.

    const std::vector<std::string>& attributes(int i) const {

      return _attributes[i];

    }

    /// @}

    /// \name Extra sections   

    /// @{

    /// \brief Gives back the number of extra sections in the file.

    ///

    /// Gives back the number of extra sections in the file.

    int extraSectionNum() const {

      return _extra_sections.size();

    }

    /// \brief Returns the extra section type at the given position. 

    ///

    /// Returns the section type at the given position. 

    const std::string& extraSection(int i) const {

      return _extra_sections[i];

    }

    /// @}

  private:

    bool readLine() {

      std::string str;

      while(++line_num, std::getline(*_is, str)) {

	line.clear(); line.str(str);

	char c;

	if (line >> std::ws >> c && c != '#') {

	  line.putback(c);

	  return true;

	}

      }

      return false;

    }

    bool readSuccess() {

      return static_cast<bool>(*_is);

    }

    void skipSection() {

      char c;

      while (readSuccess() && line >> c && c != '@') {

	readLine();

      }

      line.putback(c);

    }

    void readMaps(std::vector<std::string>& maps) {

      if (!readLine()) 

	throw DataFormatError("Cannot find map captions");

      std::string map;

      while (_reader_bits::readToken(line, map)) {

	maps.push_back(map);

      }

    }

    void readAttributes(std::vector<std::string>& attrs) {

      readLine();

      char c;

      while (readSuccess() && line >> c && c != '@') {

	line.putback(c);

	std::string attr;

	_reader_bits::readToken(line, attr);

	attrs.push_back(attr);

	readLine();

      }

      line.putback(c);

    }

  public:

    /// \name Execution of the contents reader    

    /// @{

    /// \brief Start the reading

    ///

    /// This function starts the reading

    void run() {

      readLine();

      skipSection();

      while (readSuccess()) {

	char c;

	line >> c;

	std::string section, caption;

	_reader_bits::readToken(line, section);

	_reader_bits::readToken(line, caption);

	if (section == "nodes") {

	  _node_sections.push_back(caption);

	  _node_maps.push_back(std::vector<std::string>());

	  readMaps(_node_maps.back());

	  readLine(); skipSection();

	} else if (section == "arcs" || section == "edges") {

	  _edge_sections.push_back(caption);

	  _arc_sections.push_back(section == "arcs");

	  _edge_maps.push_back(std::vector<std::string>());

	  readMaps(_edge_maps.back());

	  readLine(); skipSection();

	} else if (section == "attributes") {

	  _attribute_sections.push_back(caption);

	  _attributes.push_back(std::vector<std::string>());

	  readAttributes(_attributes.back());

	} else {

	  _extra_sections.push_back(section);

	  readLine(); skipSection();

	}

      }

    }

    /// @}

  };

}

#endif