//
// Software License for AMDiS
//
// Copyright (c) 2010 Dresden University of Technology 
// All rights reserved.
// Authors: Simon Vey, Thomas Witkowski et al.
//
// This file is part of AMDiS
//
// See also license.opensource.txt in the distribution.

#ifndef INITFILE_H
#define INITFILE_H

#include <fstream>
#include <sstream>
#include <string>
#include <map>
#include <list>
#include <set>
#include <vector>
#include <stdexcept>
#include <iostream>
#include <typeinfo>
#include "FixVec.h"

#include <boost/algorithm/string/trim.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/numeric/conversion/cast.hpp> 

#include <boost/type_traits.hpp>

// a parser for arithmetic expressions
#include "muParser.h"

namespace AMDiS {

  namespace InitfileInternal {
  
    /// Exceptions
    struct WrongVectorSize : std::runtime_error {
      WrongVectorSize(std::string m)
      : std::runtime_error(m) 
      {}
    };


    struct NoDelim : std::runtime_error {
      NoDelim(std::string m)
      : std::runtime_error(m) 
      {}
    };


    struct WrongVectorFormat : std::runtime_error {
      WrongVectorFormat(std::string m) 
      : std::runtime_error(m) 
      {}
    };

    struct GetTagError : std::runtime_error {
      GetTagError(std::string m)
      : std::runtime_error(m)
      {}
    };
    
    template<typename T>
    struct WrongValueFormat : std::runtime_error {
      static std::string name(int) 
      { 
        return "int"; 
      }

      static std::string name(bool) 
      { 
        return "bool"; 
      }

      static std::string name(double) 
      { 
        return "double"; 
      }

      static std::string name(unsigned int) 
      { 
        return "unsigned int";
      }

      template<typename G>
      static std::string name(G) 
      { 
        return std::string(typeid(G).name()); 
      }

      WrongValueFormat(std::string value)
      : std::runtime_error(std::string("cannot convert '") + 
        value + std::string("' into <") + name(T()) + ">")
      {}
    };

    template<typename T>
    struct BadArithmeticExpression : std::runtime_error {
      static std::string name(int) 
      {
        return "int";
      }

      static std::string name(bool) 
      { 
        return "bool";
      }

      static std::string name(double) 
      { 
        return "double";
      }

      static std::string name(unsigned int) 
      {
        return "unsigned int";
      }

      template<typename G>
      static std::string name(G) 
      { 
        return std::string(typeid(G).name());
      }

      BadArithmeticExpression(std::string m, std::string value) 
      : std::runtime_error(std::string("cannot evaluate expression '") + 
        value + std::string("' into <") + name(T()) + 
        ">\nParser message: '" + m + "'") 
      {}
    };


    /// trim std::string
    inline std::string trim(const std::string& oldStr) 
    {
      std::string swap(oldStr);
      boost::algorithm::trim(swap);
      return swap;
    }


    /// return the delimiter or throw an exception if there is no known 
    /// delimiter in value
    inline size_t checkDelim(const std::string& value, const std::string& delims)
    {
      size_t pos(std::string::npos);
      for (unsigned i = 0; i < delims.length(); i++) {
        pos = value.find(delims[i]);
        if (pos != std::string::npos)
          return i;
      }
      throw NoDelim("cannot detect the delimiter in " + value);
      return 0; 
    }


    /** parse an container from tag tag. The Container must have the properties:
    * 	- type value_type
    * 	- member function push_back
    */
    template< typename Container >
    inline void getContainer(const std::string val_, Container& c)
    {
      // accepted brackets and delimiters for vector input
      std::string begBrackets= "{[(";
      std::string endBrackets= "}])";
      std::string delims= ",;";

      c.clear();
      std::string val = trim(val_); 
      size_t pos = begBrackets.find(val[0]);
      if (pos == std::string::npos)
        throw WrongVectorFormat("cannot convert "
            "'" + val + "' into a list. No leading bracket found!");
      if (val[val.length() - 1] != endBrackets[pos])
        throw WrongVectorFormat("begin and end bracket are different in"
            " value '" + val + "'");
      size_t oldPos = 1;
      size_t curDelim = 0;
      typedef typename Container::value_type ValueType;
      ValueType swap;
      try {
        curDelim = checkDelim(val, delims);
        pos = val.find(delims[curDelim], oldPos);
        while (pos != std::string::npos) {
          std::string curWord = val.substr(oldPos, pos - oldPos);
          oldPos = pos + 1;
          convert(curWord, swap);
          c.push_back(swap);
          pos = val.find(delims[curDelim], oldPos);
        }
        //last entry
        std::string curWord = val.substr(oldPos, val.length() - 1 - oldPos);
        convert(curWord, swap);
        c.push_back(swap);
      } catch (NoDelim nd) {
        std::string curWord = val.substr(1, val.length() - 2);
        curWord = trim(curWord);
        if (curWord.length() > 0) {
          // container with one entry
          convert(curWord, swap);
          c.push_back(swap);
        }
      }
    }


    /// convert string to string
    inline void convert(const std::string valStr, std::string& value) 
    {
      value = trim(valStr);
    }


    /// convert string to intrinsic type
    template<typename T>
    inline void convert(const std::string valStr, T& value , 
        typename boost::enable_if<boost::is_pod<T> >::type* p = NULL , 
        typename boost::disable_if<boost::is_enum<T> >::type* p2 = NULL)
    {
      using boost::lexical_cast;
      using boost::numeric_cast;

      mu::Parser parser;
      parser.DefineConst(_T("M_PI"), m_pi);
      parser.DefineConst(_T("M_E"), m_e);

      try {
        parser.SetExpr(valStr);
        value = numeric_cast< T >(parser.Eval());
      } catch (boost::bad_lexical_cast e) {
        throw WrongValueFormat< T >(valStr);
      } catch (boost::bad_numeric_cast e) {
        throw WrongValueFormat< T >(valStr);
      } catch (mu::Parser::exception_type &e) {
        throw BadArithmeticExpression<T>(e.GetMsg(), valStr);
      }
    }


    template<typename T>
    inline void convert(const std::string valStr, T& value, 
        typename boost::enable_if< boost::is_enum< T > >::type* p = NULL) 
    {
      int swap = 0;
      try {
        swap = boost::lexical_cast<int>(trim(valStr));
      } catch (boost::bad_lexical_cast e) {
        throw WrongValueFormat< T >(valStr);
      }
      value = static_cast< T >(swap);
    }


    /// convert special enums
    inline void convert(const std::string valStr, Norm& value) 
    {
      std::string swapStr = boost::to_upper_copy(valStr);

      if (swapStr == "NO_NORM")
        value = static_cast< Norm >(NO_NORM);
      else if (swapStr == "H1_NORM")
        value = static_cast< Norm >(H1_NORM);
      else if (swapStr == "L2_NORM")
        value = static_cast< Norm >(L2_NORM);
      else {
        int swap= 0;
        convert(valStr, swap);
        value = static_cast< Norm >(swap);
      }
    }


    /// convert string to WorldVector
    template< typename T >
    inline void convert(const std::string valStr, WorldVector<T>& c) 
    {
      std::vector<T> temp_vec;
      getContainer(valStr, temp_vec);
      if (static_cast<int>(temp_vec.size()) != c.getSize())
        throw WrongVectorSize("wrong number of entries for WorldVector");
  
      for (unsigned i = 0; i < temp_vec.size(); i++)
        c[i] = temp_vec[i];
    }


    /// convert string to std::list using begBrackets, endBrackets and delims
    template<typename T>
    inline void convert(const std::string valStr, std::list<T>& value)
    {
      getContainer(valStr, value);
    }


    /// convert string to std::vector using begBrackets, endBrackets and delims
    template<typename T>
    inline void convert(const std::string valStr, std::vector<T>& value)
    {
      getContainer(valStr, value);
    }


    /// convert value of arbitrary type to string using stringstream and 
    /// operator<< for type
    template<typename T>
    inline void convert(const T value, std::string& valStr) 
    {
      std::stringstream ss;
      ss.precision(6);
      ss << value;
      valStr = ss.str();
    }


    /// convert WorldVector to string
    template<typename T>
    inline void convert(const WorldVector<T>& c, std::string& valStr)
    {
      std::vector<T> temp_vec(c.getSize());
      for (unsigned i = 0; i < temp_vec.size(); i++)
        temp_vec[i] = c[i];
      convert(temp_vec, valStr);
    }
  } // end namespace InitfileInternal


  /** The entry in an initfile. This helper class was constructed to allow calls 
  *  like val = data.get(tag) for arbitrary types of val. At current stage, only
  *  double and bool is supported
  */
  struct InitEntry {
    ///the value as string
    std::string valStr;

    /// initialize with value as string
    InitEntry(std::string v = "")
    : valStr(v) 
    {}

    /// cast string to type T
    template<typename T>
    operator T() const 
    { 
      T t; 
      convert(valStr, t); 
      return t;
    }
  };


  /// output-stream for std::list
  template<typename T>
  std::ostream& operator<<(std::ostream& o, const std::list< T >& l)
  {
    typename std::list< T >::const_iterator it = l.begin();
    o << "[";
    for (unsigned i = 0; it != l.end() && i < l.size(); i++) {
      o << *it << (i < l.size() - 1 ? ", " : "");
      ++it;
    }
    o << "]";
    return o;
  }


  /// output-stream for std::vector
  template<typename T>
  std::ostream& operator<<(std::ostream& o, const std::vector<T>& l)
  {
    typename std::vector<T>::const_iterator it = l.begin();
    o << "[";
    for (unsigned i = 0; it != l.end() && i < l.size(); i++) {
      o << *it << (i < l.size() - 1 ? ", " : "");
      ++it;
    }
    o << "]";
    return o;
  }


  /** Basis data container as a map of tag on a value as strings. The container 
  *  throws an exception, if the tag was not found.
  */
  struct Initfile : public std::map<std::string, std::string> 
  {
    typedef std::map< std::string, std::string > super;

    static const int TAG_NOT_FOUND = 1;
    static const int TAG_NOT_FOUND_BREAK = 2;

    /// Exceptions
    struct TagNotFound : std::invalid_argument {
      TagNotFound(std::string m) 
      : std::invalid_argument(m) 
      {}
    };


    struct TagNotFoundBreak : std::invalid_argument {
    // print 'tag not found' and exit
      TagNotFoundBreak(std::string m)
      : std::invalid_argument(m) 
      {}
    };


    /** initialize init-file from file with filename in, read data and save it 
    *  to singleton-map
    *  @param in: filename string
    */
    static void init(std::string in);

    static void init(int print, string filename, const char *flags = NULL) 
    {
        WARNING("Parameters::init(int,std::string,const char*) is depreciated. "
          "Use Parameters::init(std::string) instead!\n");
        init(filename);
    }


    /** Static get routine for getting parameter-values from init-file 
    *  initialized in init()-method.
    *  Cast the value to the desired type using std::stringstream.
    *  @param tag: The tag to look for
    *  @param value: The result.
    *  @param debugInfo: msgInfo for current parameter. (0..no printing,
    *    1..print missing parameter info, 2..print parameter value) [optional]
    */
    template<typename T>
    static void get(const std::string tag, T& value, int debugInfo = -1)
    {
      using namespace InitfileInternal;
      initIntern();
      if (debugInfo == -1)
        debugInfo = singlett->getMsgInfo();

      std::string valStr;
      int error_code = singlett->checkedGet(tag, valStr);
      if (error_code == 0) {
	valStr = trim(valStr);
	convert(valStr, value);
      } else if(error_code == TAG_NOT_FOUND_BREAK)
	throw TagNotFoundBreak("required tag '" + tag + "' not found");
      else if (error_code == TAG_NOT_FOUND && debugInfo == 2)
	std::cout << "there is no tag '" + tag + "'" << std::endl;
      
      if (debugInfo == 2) {
	std::cout << "Parameter '" << tag << "'"
		  << " initialized with: " << value << std::endl;
      }
    }


    /// return InitEntry object for tag tag
    static InitEntry get(const std::string tag) 
    {
      using namespace InitfileInternal;
      singlett->getMsgInfo();
      InitEntry result;
      
      std::string valStr;
      int error_code = singlett->checkedGet(tag, valStr);
      if (error_code == 0) {
	valStr = trim(valStr);
	result = InitEntry(valStr);
      } else if(error_code == TAG_NOT_FOUND_BREAK)
	throw TagNotFoundBreak("required tag '" + tag + "' not found");
      else if (error_code == TAG_NOT_FOUND)
	throw TagNotFound("there is no tag '" + tag + "'"); // exception must be thrown, because an empty object would be return otherwise
	
      return result;
    }


    /// update map tag->value_old to tag->value in singleton
    template<typename T>
    static void set(const std::string tag, T& value, int debugInfo=  -1) 
    {
      using namespace InitfileInternal;
      initIntern();
      if (debugInfo == -1)
        debugInfo = singlett->getMsgInfo();

      std::string swap = "";
      convert(value, swap);
      (*singlett)[trim(tag)] = swap;
      // update msg parameters msgInfo, msgWait, paramInfo
      singlett->getInternalParameters();
      if (debugInfo == 2)
        std::cout << "Parameter '" << tag << "'"
                  << " set to: " << value << std::endl;
    }


    /// add map tag->value to data in singleton
    template< typename T >
    static void add(const std::string tag, T& value, int debugInfo = -1) 
    {
      set(tag, value, debugInfo);
    }


    /// rescheduling parameter
    static void readArgv(int argc, char **argv);


    /// Returns specified info level
    static int getMsgInfo() 
    { 
      return (singlett != NULL) ? singlett->msgInfo : 0; 
    }


    /// Returns specified wait value
    static int getMsgWait() 
    { 
      return (singlett != NULL) ? singlett->msgWait : 0; 
    }


    /// Checks whether parameters are initialized. if not, call init()
    static bool initialized() 
    { 
      return (singlett != NULL); 
    }


    /// return pointer to singleton
    static Initfile *getSingleton() 
    { 
      return singlett; 
    }


    /// print all data in singleton to std::cout
    static void printParameters();


    /// clear data in singleton
    static void clearData()
    {
      initIntern();
      singlett->clear();
    }


    /// save singlett-data to file with filename fn
    static void save(std::string fn)
    {
      initIntern();
      singlett->write(fn);
    }
	
protected:	
    Initfile() 
    : msgInfo(0), 
      msgWait(1), 
      paramInfo(1), 
      breakOnMissingTag(0) 
    {}


    static void initIntern() 
    {
      if (singlett == NULL)
	      singlett = new Initfile;
    }


    /// list of processed files
    static std::set< std::string > fn_include_list;


    /// pointer to the singleton that contains the data
    static Initfile* singlett;


    /// return the value of the given tag or throws an exception if the tag 
    /// does not exist
    int checkedGet(const std::string& tag, std::string &valStr) const
    {
      super::const_iterator it = find(tag);
      if (it == end()) {
        if (breakOnMissingTag == 0 || msgInfo <= 2)
	  return TAG_NOT_FOUND;
        else
	  return TAG_NOT_FOUND_BREAK;
      }
      valStr = it->second;

      return 0;
    }

    /// replace variables by its value defined as parameter previousely
    /// variable definition is simple parameter definition
    /// variable evaluation by ${variablename} or $variablename
    /// the last version only for variablenames without whitespaces
    std::string variableReplacement(const std::string& input) const;

    /** Fill the initfile from an input stream.
    * @param in: the stream to fill the data from.
    * Current dataformat: tag:value
    * Comment char: percent '%'
    * Include files: #include "filename" or #include <filename>
    */
    void read(std::istream& in);

    /// Fill the initfile from a file with filename fn
    void read(std::string fn, bool force = false);

    /** Write data-map to initfile
    * @param out: the stream to fill the data in.
    */
    void write(std::ostream& out);

    /// Write data-map to initfile with filename fn
    void write(std::string fn);

    /// read parameters for msgInfo, msgWait, paramInfo
    void getInternalParameters();

    int msgInfo, msgWait, paramInfo, breakOnMissingTag;	
  };
  
  typedef Initfile Parameters;

} // end namespace AMDiS
#endif