#ifndef __JTRIGGER__JPREPROCESSOR__
#define __JTRIGGER__JPREPROCESSOR__

#include <string>
#include <utility>
#include <vector>
#include <algorithm>

#include "JLang/JException.hh"
#include "JLang/JPredicate.hh"
#include "JLang/JVectorize.hh"


/**
 * \file
 *
 * Auxiliaries for pre-processing of hits.
 * \author mdejong
 */
namespace JTRIGGER {}
namespace JPP { using namespace JTRIGGER; }

namespace JTRIGGER {

  using JLANG::JTypeInformationException;


  /**
   * Auxiliary class for specifying the way of pre-processing of hits.
   */
  struct JPreprocessor :
    public std::string
  {
    /**
     * Preprocessing options.
     */
    enum JOption_t {
      none_t    = 0,     //!< no pre-processing
      join_t,            //!< join   consecutive hits according match criterion
      filter_t,          //!< filter consecutive hits according match criterion
      remove_t           //!< remove consecutive hits according match criterion
    };


    typedef std::pair<JPreprocessor, JOption_t>              pair_type;
    typedef std::vector<pair_type>                           data_type;


    /**
     * Default constructor.
     */
    JPreprocessor() :
      std::string(get_options()[0].first)
    {}
    

    /**
     * Type conversion operator.
     *
     * \return            option
     */
    operator JOption_t () const
    {
      return JPreprocessor::getOption(*this);
    }


    /**
     * Get option.
     *
     * \param  option     option
     * \return            option
     */
    static JOption_t getOption(const JPreprocessor& option)
    {
      using namespace std;
      using namespace JPP;

      data_type::const_iterator i = find_if(get_options().begin(), 
					    get_options().end(),
					    make_predicate(&pair_type::first, JPreprocessor(option)));

      if (i != get_options().end()) {
	return i->second;
      } else {
	THROW(JTypeInformationException, "Invalid option <" << option << ">");
      }
    };


    /**
     * Get option.
     *
     * \param  option     option
     * \return            option
     */
    static JPreprocessor getOption(const JOption_t option)
    {
      using namespace std;
      using namespace JPP;

      data_type::const_iterator i = find_if(get_options().begin(), 
					    get_options().end(),
					    make_predicate(&pair_type::second, option));

      if (i != get_options().end()) {
	return i->first;
      } else {
	THROW(JTypeInformationException, "Invalid option <" << option << ">");
      }
    };
    
    
    /**
     * Get options.
     *
     * \return            list of options
     */
    static std::vector<JPreprocessor> getOptions() 
    {
      return JLANG::make_array(get_options().begin(), 
			       get_options().end(),
			       &pair_type::first);
    }
    
    
    /**
     * Get options.
     *
     * \param  option     option
     * \return            list of options
     */
    static std::vector<JPreprocessor> getOptions(const JOption_t option)
    {
      std::vector<JPreprocessor> buffer(1, getOption(option));

      for (const auto& i : get_options()) {
	if (i.second != option) {
	  buffer.push_back(i.first);
	}
      }

      return buffer;
    }

  protected:

    static const char ENUM_EXTENSION = '_';   //!< Extension of enumeration names.

    /**
     * Constructor.
     *
     * \param  option     option
     */
    JPreprocessor(const std::string& option) :
      std::string(option)
    {
      using namespace std;

      const string::size_type pos = this->rfind(ENUM_EXTENSION);

      if (pos != string::npos) {
	this->erase(pos);
      }
    }


    /**
     * Get paired options.
     *
     * \return            list of paired options
     */
    static const data_type& get_options()
    {
      static data_type buffer;

      if (buffer.empty()) {

#define MAKE_ENTRY(A) std::make_pair(JPreprocessor(#A), A)

	buffer.push_back(MAKE_ENTRY(none_t));
	buffer.push_back(MAKE_ENTRY(join_t));
	buffer.push_back(MAKE_ENTRY(filter_t));
	buffer.push_back(MAKE_ENTRY(remove_t));
	
#undef MAKE_ENTRY
      }

      return buffer;
    }
  };
}

#endif