text: // Copyright (c) 2014-2018, The goplb Project
  // 
  // All rights reserved.
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  // Redistribution and use in source and binary forms, with or without modification, are
  // permitted provided that the following conditions are met:
  // 
  // 1. Redistributions of source code must retain the above copyright notice, this list of
  //    conditions and the following disclaimer.
  // 
  // 2. Redistributions in binary form must reproduce the above copyright notice, this list
  //    of conditions and the following disclaimer in the documentation and/or other
  //    materials provided with the distribution.
  // 
  // 3. Neither the name of the copyright holder nor the names of its contributors may be
  //    used to endorse or promote products derived from this software without specific
  //    prior written permission.
  // 
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
  // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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  // THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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  // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  // 
  // Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
  
  #pragma once
  
  #include <functional>
  #include <iostream>
  #include <sstream>
  #include <array>
  #include <type_traits>
  
  #include <boost/program_options/parsers.hpp>
  #include <boost/program_options/options_description.hpp>
  #include <boost/program_options/variables_map.hpp>
  #include "include_base_utils.h"
  
  namespace command_line
  {
  
    //! \return True if `str` is `is_iequal("y" || "yes" || `tr("yes"))`.
    bool is_yes(const std::string& str);
    //! \return True if `str` is `is_iequal("n" || "no" || `tr("no"))`.
    bool is_no(const std::string& str);
  
    template<typename T, bool required = false, bool dependent = false, int NUM_DEPS = 1>
    struct arg_descriptor;
  
    template<typename T>
    struct arg_descriptor<T, false>
    {
      typedef T value_type;
  
      const char* name;
      const char* description;
      T default_value;
      bool not_use_default;
    };
  
    template<typename T>
    struct arg_descriptor<std::vector<T>, false>
    {
      typedef std::vector<T> value_type;
  
      const char* name;
      const char* description;
    };
  
    template<typename T>
    struct arg_descriptor<T, true>
    {
      static_assert(!std::is_same<T, bool>::value, "Boolean switch can't be required");
  
      typedef T value_type;
  
      const char* name;
      const char* description;
    };
  
    template<typename T>
    struct arg_descriptor<T, false, true>
    {
      typedef T value_type;
  
      const char* name;
      const char* description;
  
      T default_value;
  
      const arg_descriptor<bool, false>& ref;
      std::function<T(bool, bool, T)> depf;
  
      bool not_use_default;
    };
  
    template<typename T, int NUM_DEPS>
    struct arg_descriptor<T, false, true, NUM_DEPS>
    {
      typedef T value_type;
  
      const char* name;
      const char* description;
  
      T default_value;
  
      std::array<const arg_descriptor<bool, false> *, NUM_DEPS> ref;
      std::function<T(std::array<bool, NUM_DEPS>, bool, T)> depf;
  
      bool not_use_default;
    };
  
    template<typename T>
    boost::program_options::typed_value<T, char>* make_semantic(const arg_descriptor<T, true>& /*arg*/)
    {
      return boost::program_options::value<T>()->required();
    }
  
    template<typename T>
    boost::program_options::typed_value<T, char>* make_semantic(const arg_descriptor<T, false>& arg)
    {
      auto semantic = boost::program_options::value<T>();
      if (!arg.not_use_default)
        semantic->default_value(arg.default_value);
      return semantic;
    }
  
    template<typename T>
    boost::program_options::typed_value<T, char>* make_semantic(const arg_descriptor<T, false, true>& arg)
    {
      auto semantic = boost::program_options::value<T>();
      if (!arg.not_use_default) {
        std::ostringstream format;
        format << arg.depf(false, true, arg.default_value) << ", "
               << arg.depf(true, true, arg.default_value) << " if '"
               << arg.ref.name << "'";
        semantic->default_value(arg.depf(arg.ref.default_value, true, arg.default_value), format.str());
      }
      return semantic;
    }
  
    template<typename T, int NUM_DEPS>
    boost::program_options::typed_value<T, char>* make_semantic(const arg_descriptor<T, false, true, NUM_DEPS>& arg)
    {
      auto semantic = boost::program_options::value<T>();
      if (!arg.not_use_default) {
        std::array<bool, NUM_DEPS> depval;
        depval.fill(false);
        std::ostringstream format;
        format << arg.depf(depval, true, arg.default_value);
        for (size_t i = 0; i < depval.size(); ++i)
        {
          depval.fill(false);
          depval[i] = true;
          format << ", " << arg.depf(depval, true, arg.default_value) << " if '" << arg.ref[i]->name << "'";
        }
        for (size_t i = 0; i < depval.size(); ++i)
          depval[i] = arg.ref[i]->default_value;
        semantic->default_value(arg.depf(depval, true, arg.default_value), format.str());
      }
      return semantic;
    }
  
    template<typename T>
    boost::program_options::typed_value<T, char>* make_semantic(const arg_descriptor<T, false>& arg, const T& def)
    {
      auto semantic = boost::program_options::value<T>();
      if (!arg.not_use_default)
        semantic->default_value(def);
      return semantic;
    }
  
    template<typename T>
    boost::program_options::typed_value<std::vector<T>, char>* make_semantic(const arg_descriptor<std::vector<T>, false>& /*arg*/)
    {
      auto semantic = boost::program_options::value< std::vector<T> >();
      semantic->default_value(std::vector<T>(), "");
      return semantic;
    }
  
    template<typename T, bool required, bool dependent, int NUM_DEPS>
    void add_arg(boost::program_options::options_description& description, const arg_descriptor<T, required, dependent, NUM_DEPS>& arg, bool unique = true)
    {
      if (0 != description.find_nothrow(arg.name, false))
      {
        CHECK_AND_ASSERT_MES(!unique, void(), "Argument already exists: " << arg.name);
        return;
      }
  
      description.add_options()(arg.name, make_semantic(arg), arg.description);
    }
  
    template<typename T>
    void add_arg(boost::program_options::options_description& description, const arg_descriptor<T, false>& arg, const T& def, bool unique = true)
    {
      if (0 != description.find_nothrow(arg.name, false))
      {
        CHECK_AND_ASSERT_MES(!unique, void(), "Argument already exists: " << arg.name);
        return;
      }
  
      description.add_options()(arg.name, make_semantic(arg, def), arg.description);
    }
  
    template<>
    inline void add_arg(boost::program_options::options_description& description, const arg_descriptor<bool, false>& arg, bool unique)
    {
      if (0 != description.find_nothrow(arg.name, false))
      {
        CHECK_AND_ASSERT_MES(!unique, void(), "Argument already exists: " << arg.name);
        return;
      }
  
      description.add_options()(arg.name, boost::program_options::bool_switch(), arg.description);
    }
  
    template<typename charT>
    boost::program_options::basic_parsed_options<charT> parse_command_line(int argc, const charT* const argv[],
      const boost::program_options::options_description& desc, bool allow_unregistered = false)
    {
      auto parser = boost::program_options::command_line_parser(argc, argv);
      parser.options(desc);
      if (allow_unregistered)
      {
        parser.allow_unregistered();
      }
      return parser.run();
    }
  
    template<typename F>
    bool handle_error_helper(const boost::program_options::options_description& desc, F parser)
    {
      try
      {
        return parser();
      }
      catch (const std::exception& e)
      {
        std::cerr << "Failed to parse arguments: " << e.what() << std::endl;
        std::cerr << desc << std::endl;
        return false;
      }
      catch (...)
      {
        std::cerr << "Failed to parse arguments: unknown exception" << std::endl;
        std::cerr << desc << std::endl;
        return false;
      }
    }
  
    template<typename T, bool required, bool dependent, int NUM_DEPS>
    typename std::enable_if<!std::is_same<T, bool>::value, bool>::type has_arg(const boost::program_options::variables_map& vm, const arg_descriptor<T, required, dependent, NUM_DEPS>& arg)
    {
      auto value = vm[arg.name];
      return !value.empty();
    }
  
    template<typename T, bool required, bool dependent, int NUM_DEPS>
    bool is_arg_defaulted(const boost::program_options::variables_map& vm, const arg_descriptor<T, required, dependent, NUM_DEPS>& arg)
    {
      return vm[arg.name].defaulted();
    }
  
    template<typename T>
    T get_arg(const boost::program_options::variables_map& vm, const arg_descriptor<T, false, true>& arg)
    {
      return arg.depf(get_arg(vm, arg.ref), is_arg_defaulted(vm, arg), vm[arg.name].template as<T>());
    }
  
    template<typename T, int NUM_DEPS>
    T get_arg(const boost::program_options::variables_map& vm, const arg_descriptor<T, false, true, NUM_DEPS>& arg)
    {
      std::array<bool, NUM_DEPS> depval;
      for (size_t i = 0; i < depval.size(); ++i)
        depval[i] = get_arg(vm, *arg.ref[i]);
      return arg.depf(depval, is_arg_defaulted(vm, arg), vm[arg.name].template as<T>());
    }
  
    template<typename T, bool required>
    T get_arg(const boost::program_options::variables_map& vm, const arg_descriptor<T, required>& arg)
    {
      return vm[arg.name].template as<T>();
    }
   
    template<bool dependent, int NUM_DEPS>
    inline bool has_arg(const boost::program_options::variables_map& vm, const arg_descriptor<bool, false, dependent, NUM_DEPS>& arg)
    {
      return get_arg(vm, arg);
    }
  
  
    extern const arg_descriptor<bool> arg_help;
    extern const arg_descriptor<bool> arg_version;
  }
  