/* -*- C++ -*-

  * src/lemon/graph_writer.h - Part of LEMON, a generic C++ optimization library

  *

  * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

  * (Egervary Combinatorial Optimization Research Group, EGRES).

  *

  * Permission to use, modify and distribute this software is granted

  * provided that this copyright notice appears in all copies. For

  * precise terms see the accompanying LICENSE file.

  *

  * This software is provided "AS IS" with no warranty of any kind,

  * express or implied, and with no claim as to its suitability for any

  * purpose.

  *

  */

 ///\ingroup gio

 ///\file

 ///\brief Graph writer.

 #include <iostream>

 #include <sstream>

 #include <map>

 #include <vector>

 #include <memory>

 #include <lemon/invalid.h>

 #include <lemon/error.h>

 namespace lemon {

   /// \brief Standard WriterTraits for the GraphWriter class.

   ///

   /// Standard WriterTraits for the GraphWriter class.

   /// It defines standard writing method for all type of value. 

   struct DefaultWriterTraits {

     /// \brief Template class for writing an value.

     ///

     /// Template class for writing an value.

     template <typename _Value>

     struct Writer {

       /// The value type.

       typedef _Value Value;

       /// \brief Writes a value from the given stream.

       ///

       /// Writes a value from the given stream.

       void write(std::ostream& os, const Value& value) {

 	os << value << '\t';

       }

     };

   };

   /// \brief Writer class for quoted strings.

   ///

   /// Writer class for quoted strings. It can process the escape

   /// sequences in the string.

   class QuotedStringWriter {

   public:

     typedef std::string Value;

     /// \brief Constructor for the writer.

     ///

     /// Constructor for the writer. If the given parameter is true

     /// the writer creates escape sequences from special characters.

     QuotedStringWriter(bool _escaped = true) : escaped(_escaped) {}

     /// \brief Writes a quoted string from the given stream.

     ///

     /// Writes a quoted string from the given stream.

     void write(std::ostream& os, const std::string& value) {

       os << "\"";

       if (escaped) {

 	ostringstream ls;

 	for (int i = 0; i < (int)value.size(); ++i) {

 	  writeEscape(ls, value[i]);

 	}

 	os << ls.str();

       } else {

 	os << value;

       }

       os << "\"";

     }

   private:

     static void writeEscape(std::ostream& os, char c) {

       switch (c) {

       case '\\':

 	os << "\\\\";

 	return;

       case '\"':

 	os << "\\\"";

 	return;

       case '\'':

 	os << "\\\'";

 	return;

       case '\?':

 	os << "\\\?";

 	return;

       case '\a':

 	os << "\\a";

 	return;

       case '\b':

 	os << "\\b";

 	return;

       case '\f':

 	os << "\\f";

 	return;

       case '\r':

 	os << "\\r";

 	return;

       case '\n':

 	os << "\\n";

 	return;

       case '\t':

 	os << "\\t";

 	return;

       case '\v':

 	os << "\\v";

 	return;

       default:

 	if (c < 0x20) {

 	  os << '\\' << oct << (int)c;

 	} else {

 	  os << c;

 	}

 	return;

       }     

     }

   private:

     bool escaped;

   };

   /// \brief The graph writer class.

   ///

   /// The writer class for the graph output.

   /// \see \ref GraphReader

   /// \see \ref graph-io-page

   template <typename _Graph, typename _WriterTraits = DefaultWriterTraits> 

   class GraphWriter {

   public:

     typedef _Graph Graph;

     typedef typename Graph::Node Node;

     typedef typename Graph::NodeIt NodeIt;

     typedef typename Graph::Edge Edge;

     typedef typename Graph::EdgeIt EdgeIt;

     typedef _WriterTraits WriterTraits;

     /// \brief Construct a new GraphWriter.

     ///

     /// Construct a new GraphWriter. It writes from the given map,

     /// it constructs the given map and it use the given writer as the

     /// default skipper.

     GraphWriter(std::ostream& _os, Graph& _graph) : os(_os), graph(_graph) {}

     /// \brief Destruct the graph writer.

     ///

     /// Destruct the graph writer.

     ~GraphWriter() {

       for (typename NodeMapWriters::iterator it = node_map_writers.begin(); 

 	   it != node_map_writers.end(); ++it) {

 	delete it->second;

       }

       for (typename EdgeMapWriters::iterator it = edge_map_writers.begin();

 	   it != edge_map_writers.end(); ++it) {

 	delete it->second;

       }

     }

     // Node map rules

     /// \brief Add a new node map writer command for the writer.

     ///

     /// Add a new node map writer command for the writer.

     template <typename Map>

     GraphWriter& addNodeMap(std::string name, const Map& map) {

       return addNodeMap<typename WriterTraits::template Writer<

 	typename Map::Value>, Map>(name, map);

     }

     /// \brief Add a new node map writer command for the writer.

     ///

     /// Add a new node map writer command for the writer.

     template <typename Writer, typename Map>

     GraphWriter& addNodeMap(std::string name, const Map& map, 

 			      const Writer& writer = Writer()) {

       node_map_writers.push_back(

         make_pair(name, new MapWriter<Node, Map, Writer>(map, writer)));

       return *this;

     }

     // Edge map rules

     /// \brief Add a new edge map writer command for the writer.

     ///

     /// Add a new edge map writer command for the writer.

     template <typename Map>

     GraphWriter& addEdgeMap(std::string name, const Map& map) { 

       return addEdgeMap<typename WriterTraits::template Writer<

         typename Map::Value>, Map>(name, map);

     }

     /// \brief Add a new edge map writer command for the writer.

     ///

     /// Add a new edge map writer command for the writer.

     template <typename Writer, typename Map>

     GraphWriter& addEdgeMap(std::string name, 

 			    const Map& map, const Writer& writer = Writer()) {

       edge_map_writers.push_back(make_pair(name, 

 	new MapWriter<Edge, Map, Writer>(map, writer)));

       return *this;

     }

     /// \brief Add a new labeled node writer for the writer.

     ///

     /// Add a new labeled node writer for the writer.

     GraphWriter& addNode(std::string name, const Node& node) {

       node_writers.push_back(make_pair(name, node));

       return *this;

     }

     /// \brief Add a new labeled edge writer for the writer.

     ///

     /// Add a new labeled edge writer for the writer.

     GraphWriter& addEdge(std::string name, const Edge& edge) {

       edge_writers.push_back(make_pair(name, edge));

       return *this;

     }

     /// \brief Executes the writer commands.

     ///

     /// Executes the writer commands.

     void run() {   

       writeNodeSet();

       writeEdgeSet();

       writeNodes();

       writeEdges();

       os << "@end" << std::endl;

     }

   private:

     void writeNodeSet() {

       if (node_map_writers.size() == 0) return;

       os << "@nodeset" << std::endl;

       for (int i = 0; i < (int)node_map_writers.size(); ++i) {

 	os << node_map_writers[i].first << '\t';

       } 

       os << std::endl;

       for (NodeIt it(graph); it != INVALID; ++it) {

 	for (int i = 0; i < (int)node_map_writers.size(); ++i) {

 	  node_map_writers[i].second->write(os, it);

 	}

 	os << std::endl;

       }

     }

     void writeEdgeSet() {

       if (edge_map_writers.size() == 0) return;

       if (node_map_writers.size() == 0) {

 	throw Exception() << "Missing node id map";

       }

       os << "@edgeset" << std::endl;

       os << "\t\t";

       for (int i = 0; i < (int)edge_map_writers.size(); ++i) {

 	os << edge_map_writers[i].first << '\t';

       } 

       os << std::endl;

       for (EdgeIt it(graph); it != INVALID; ++it) {

 	node_map_writers[0].second->write(os, graph.source(it));

 	node_map_writers[0].second->write(os, graph.target(it));

 	for (int i = 0; i < (int)edge_map_writers.size(); ++i) {

 	  edge_map_writers[i].second->write(os, it);

 	}

 	os << std::endl;

       }

     }

     void writeNodes() {

       if (node_writers.size() == 0) return;

       if (node_map_writers.size() == 0) {

 	throw Exception() << "Missing node id map";

       }

       os << "@nodes" << std::endl;

       for (int i = 0; i < (int)node_writers.size(); ++i) {

 	os << node_writers[i].first << '\t';

 	node_map_writers[0].second->write(os, node_writers[i].second);

 	os << std::endl;

       } 

     }

     void writeEdges() {

       if (edge_writers.size() == 0) return;

       if (edge_map_writers.size() == 0) {

 	throw Exception() << "Missing edge id map";

       }

       os << "@edges" << std::endl;

       for (int i = 0; i < (int)edge_writers.size(); ++i) {

 	os << edge_writers[i].first << '\t';

 	edge_map_writers[0].second->write(os, edge_writers[i].second);

 	os << std::endl;

       } 

     }

     // Writers

     template <class _Item>

     class WriterBase {

     public:

       typedef _Item Item;

       virtual void write(std::ostream&, const Item&) = 0;

     };

     template <class _Item, typename _Map, typename _Writer>

     class MapWriter : public WriterBase<_Item> {

     public:

       typedef _Map Map;

       typedef _Writer Writer;

       typedef typename Writer::Value Value;

       typedef _Item Item;

       const Map& map;

       Writer writer;

       MapWriter(const Map& _map, const Writer& _writer) 

 	: map(_map), writer(_writer) {}

       virtual void write(std::ostream& os, const Item& item) {

 	writer.write(os, map[item]);

       }

     };

     typedef std::vector< std::pair<std::string, WriterBase<Node>*> > 

       NodeMapWriters;

     NodeMapWriters node_map_writers;

     typedef std::vector< std::pair<std::string, WriterBase<Edge>*> > 

       EdgeMapWriters;

     EdgeMapWriters edge_map_writers;

     typedef std::vector<std::pair<std::string, Node> > NodeWriters;

     NodeWriters node_writers;

     typedef std::vector<std::pair<std::string, Edge> > EdgeWriters;

     EdgeWriters edge_writers;

     std::ostream& os;

     Graph& graph;

   };

 }