/* -*- mode: C++; indent-tabs-mode: nil; -*-

 *

 * This file is a part of LEMON, a generic C++ optimization library.

 *

 * Copyright (C) 2003-2010

 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, 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.

 *

 */

#ifndef LEMON_ARG_PARSER_H

#define LEMON_ARG_PARSER_H

#include <vector>

#include <map>

#include <list>

#include <string>

#include <iostream>

#include <sstream>

#include <algorithm>

#include <lemon/assert.h>

///\ingroup misc

///\file

///\brief A tool to parse command line arguments.

namespace lemon {

  ///Exception used by ArgParser

  ///Exception used by ArgParser.

  ///

  class ArgParserException : public Exception {

  public:

    /// Reasons for failure

    /// Reasons for failure.

    ///

    enum Reason {

      HELP,         ///< <tt>--help</tt> option was given.

      UNKNOWN_OPT,  ///< Unknown option was given.

      INVALID_OPT   ///< Invalid combination of options.

    };

  private:

    Reason _reason;

  public:

    ///Constructor

    ArgParserException(Reason r) throw() : _reason(r) {}

    ///Virtual destructor

    virtual ~ArgParserException() throw() {}

    ///A short description of the exception

    virtual const char* what() const throw() {

      switch(_reason)

        {

        case HELP:

          return "lemon::ArgParseException: ask for help";

          break;

        case UNKNOWN_OPT:

          return "lemon::ArgParseException: unknown option";

          break;

        case INVALID_OPT:

          return "lemon::ArgParseException: invalid combination of options";

          break;

        }

      return "";

    }

    ///Return the reason for the failure

    Reason reason() const {return _reason; }

  };

  ///Command line arguments parser

  ///\ingroup misc

  ///Command line arguments parser.

  ///

  ///For a complete example see the \ref arg_parser_demo.cc demo file.

  class ArgParser {

    static void _showHelp(void *p);

  protected:

    int _argc;

    const char * const *_argv;

    enum OptType { UNKNOWN=0, BOOL=1, STRING=2, DOUBLE=3, INTEGER=4, FUNC=5 };

    class ParData {

    public:

      union {

        bool *bool_p;

        int *int_p;

        double *double_p;

        std::string *string_p;

        struct {

          void (*p)(void *);

          void *data;

        } func_p;

      };

      std::string help;

      bool mandatory;

      OptType type;

      bool set;

      bool ingroup;

      bool has_syn;

      bool syn;

      bool self_delete;

      ParData() : mandatory(false), type(UNKNOWN), set(false), ingroup(false),

                  has_syn(false), syn(false), self_delete(false) {}

    };

    typedef std::map<std::string,ParData> Opts;

    Opts _opts;

    class GroupData

    {

    public:

      typedef std::list<std::string> Opts;

      Opts opts;

      bool only_one;

      bool mandatory;

      GroupData() :only_one(false), mandatory(false) {}

    };

    typedef std::map<std::string,GroupData> Groups;

    Groups _groups;

    struct OtherArg

    {

      std::string name;

      std::string help;

      OtherArg(std::string n, std::string h) :name(n), help(h) {}

    };

    std::vector<OtherArg> _others_help;

    std::vector<std::string> _file_args;

    std::string _command_name;

  private:

    //Bind a function to an option.

    //\param name The name of the option. The leading '-' must be omitted.

    //\param help A help string.

    //\retval func The function to be called when the option is given. It

    //  must be of type "void f(void *)"

    //\param data Data to be passed to \c func

    ArgParser &funcOption(const std::string &name,

                    const std::string &help,

                    void (*func)(void *),void *data);

    bool _exit_on_problems;

    void _terminate(ArgParserException::Reason reason) const;

  public:

    ///Constructor

    ArgParser(int argc, const char * const *argv);

    ~ArgParser();

    ///\name Options

    ///

    ///@{

    ///Add a new integer type option

    ///Add a new integer type option.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param value A default value for the option.

    ///\param obl Indicate if the option is mandatory.

    ArgParser &intOption(const std::string &name,

                    const std::string &help,

                    int value=0, bool obl=false);

    ///Add a new floating point type option

    ///Add a new floating point type option.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param value A default value for the option.

    ///\param obl Indicate if the option is mandatory.

    ArgParser &doubleOption(const std::string &name,

                      const std::string &help,

                      double value=0, bool obl=false);

    ///Add a new bool type option

    ///Add a new bool type option.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param value A default value for the option.

    ///\param obl Indicate if the option is mandatory.

    ///\note A mandatory bool obtion is of very little use.

    ArgParser &boolOption(const std::string &name,

                      const std::string &help,

                      bool value=false, bool obl=false);

    ///Add a new string type option

    ///Add a new string type option.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param value A default value for the option.

    ///\param obl Indicate if the option is mandatory.

    ArgParser &stringOption(const std::string &name,

                      const std::string &help,

                      std::string value="", bool obl=false);

    ///Give help string for non-parsed arguments.

    ///With this function you can give help string for non-parsed arguments.

    ///The parameter \c name will be printed in the short usage line, while

    ///\c help gives a more detailed description.

    ArgParser &other(const std::string &name,

                     const std::string &help="");

    ///@}

    ///\name Options with External Storage

    ///Using this functions, the value of the option will be directly written

    ///into a variable once the option appears in the command line.

    ///@{

    ///Add a new integer type option with a storage reference

    ///Add a new integer type option with a storage reference.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param obl Indicate if the option is mandatory.

    ///\retval ref The value of the argument will be written to this variable.

    ArgParser &refOption(const std::string &name,

                    const std::string &help,

                    int &ref, bool obl=false);

    ///Add a new floating type option with a storage reference

    ///Add a new floating type option with a storage reference.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param obl Indicate if the option is mandatory.

    ///\retval ref The value of the argument will be written to this variable.

    ArgParser &refOption(const std::string &name,

                      const std::string &help,

                      double &ref, bool obl=false);

    ///Add a new bool type option with a storage reference

    ///Add a new bool type option with a storage reference.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param obl Indicate if the option is mandatory.

    ///\retval ref The value of the argument will be written to this variable.

    ///\note A mandatory bool obtion is of very little use.

    ArgParser &refOption(const std::string &name,

                      const std::string &help,

                      bool &ref, bool obl=false);

    ///Add a new string type option with a storage reference

    ///Add a new string type option with a storage reference.

    ///\param name The name of the option. The leading '-' must be omitted.

    ///\param help A help string.

    ///\param obl Indicate if the option is mandatory.

    ///\retval ref The value of the argument will be written to this variable.

    ArgParser &refOption(const std::string &name,

                      const std::string &help,

                      std::string &ref, bool obl=false);

    ///@}

    ///\name Option Groups and Synonyms

    ///

    ///@{

    ///Bundle some options into a group

    /// You can group some option by calling this function repeatedly for each

    /// option to be grouped with the same groupname.

    ///\param group The group name.

    ///\param opt The option name.

    ArgParser &optionGroup(const std::string &group,

                           const std::string &opt);

    ///Make the members of a group exclusive

    ///If you call this function for a group, than at most one of them can be

    ///given at the same time.

    ArgParser &onlyOneGroup(const std::string &group);

    ///Make a group mandatory

    ///Using this function, at least one of the members of \c group

    ///must be given.

    ArgParser &mandatoryGroup(const std::string &group);

    ///Create synonym to an option

    ///With this function you can create a synonym \c syn of the

    ///option \c opt.

    ArgParser &synonym(const std::string &syn,

                           const std::string &opt);

    ///@}

  private:

    void show(std::ostream &os,Opts::const_iterator i) const;

    void show(std::ostream &os,Groups::const_iterator i) const;

    void showHelp(Opts::const_iterator i) const;

    void showHelp(std::vector<OtherArg>::const_iterator i) const;

    void unknownOpt(std::string arg) const;

    void requiresValue(std::string arg, OptType t) const;

    void checkMandatories() const;

    void shortHelp() const;

    void showHelp() const;

  public:

    ///Start the parsing process

    ArgParser &parse();

    /// Synonym for parse()

    ArgParser &run()

    {

      return parse();

    }

    ///Give back the command name (the 0th argument)

    const std::string &commandName() const { return _command_name; }

    ///Check if an opion has been given to the command.

    bool given(std::string op) const

    {

      Opts::const_iterator i = _opts.find(op);

      return i!=_opts.end()?i->second.set:false;

    }

    ///Magic type for operator[]

    ///This is the type of the return value of ArgParser::operator[]().

    ///It automatically converts to \c int, \c double, \c bool or

    ///\c std::string if the type of the option matches, which is checked

    ///with an \ref LEMON_ASSERT "assertion" (i.e. it performs runtime

    ///type checking).

    class RefType

    {

      const ArgParser &_parser;

      std::string _name;

    public:

      ///\e

      RefType(const ArgParser &p,const std::string &n) :_parser(p),_name(n) {}

      ///\e

      operator bool()

      {

        Opts::const_iterator i = _parser._opts.find(_name);

        LEMON_ASSERT(i!=_parser._opts.end(),

                     std::string()+"Unkown option: '"+_name+"'");

        LEMON_ASSERT(i->second.type==ArgParser::BOOL,

                     std::string()+"'"+_name+"' is a bool option");

        return *(i->second.bool_p);

      }

      ///\e

      operator std::string()

      {

        Opts::const_iterator i = _parser._opts.find(_name);

        LEMON_ASSERT(i!=_parser._opts.end(),

                     std::string()+"Unkown option: '"+_name+"'");

        LEMON_ASSERT(i->second.type==ArgParser::STRING,

                     std::string()+"'"+_name+"' is a string option");

        return *(i->second.string_p);

      }

      ///\e

      operator double()

      {

        Opts::const_iterator i = _parser._opts.find(_name);

        LEMON_ASSERT(i!=_parser._opts.end(),

                     std::string()+"Unkown option: '"+_name+"'");

        LEMON_ASSERT(i->second.type==ArgParser::DOUBLE ||

                     i->second.type==ArgParser::INTEGER,

                     std::string()+"'"+_name+"' is a floating point option");

        return i->second.type==ArgParser::DOUBLE ?

          *(i->second.double_p) : *(i->second.int_p);

      }

      ///\e

      operator int()

      {

        Opts::const_iterator i = _parser._opts.find(_name);

        LEMON_ASSERT(i!=_parser._opts.end(),

                     std::string()+"Unkown option: '"+_name+"'");

        LEMON_ASSERT(i->second.type==ArgParser::INTEGER,

                     std::string()+"'"+_name+"' is an integer option");

        return *(i->second.int_p);

      }

    };

    ///Give back the value of an option

    ///Give back the value of an option.

    ///\sa RefType

    RefType operator[](const std::string &n) const

    {

      return RefType(*this, n);

    }

    ///Give back the non-option type arguments.

    ///Give back a reference to a vector consisting of the program arguments

    ///not starting with a '-' character.

    const std::vector<std::string> &files() const { return _file_args; }

    ///Throw instead of exit in case of problems

    void throwOnProblems()

    {

      _exit_on_problems=false;

    }

  };

}

#endif // LEMON_ARG_PARSER_H