Arguments.cpp

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#include "joedb/ui/Arguments.h"
#include "joedb/error/assert.h"
 
namespace joedb
{
 Arguments::Argument::Argument(const char *argv): s(argv), used(false)
 {
  if (s[0] == '-' && s[1] == '-')
   option = std::string_view(s.data() + 2, s.size() - 2);
 }
 
 void Arguments::update_index()
 {
  while (index < argc && args[index].used)
   index++;
 }
 
 std::string_view Arguments::use_index()
 {
  JOEDB_DEBUG_ASSERT(index < argc);
  args[index].used = true;
  const auto result = args[index].s;
  update_index();
  return result;
 }
 
 Arguments::Arguments(int argc, const char * const *argv):
  argc(argc),
  argv(argv)
 {
  args.reserve(argc);
  for (int i = 0; i < argc; i++)
   args.emplace_back(argv[i]);
 }
 
 bool Arguments::has_flag(const char * name)
 {
  options.emplace_back(name, std::string_view{});
 
  for (auto &arg: args)
  {
   if (arg.option == name)
   {
    arg.used = true;
    update_index();
    return true;
   }
  }
 
  return false;
 }
 
 std::string_view Arguments::get_string_option
 (
  const char * name,
  const char * description,
  const char * default_string
 )
 {
  options.emplace_back(name, description);
 
  for (size_t i = 0; i < args.size() - 1; i++)
  {
   if (args[i].option == name)
   {
    args[i].used = true;
    args[i + 1].used = true;
    update_index();
    return args[i + 1].s;
   }
  }
 
  return default_string;
 }
 
 size_t Arguments::get_enum_option
 (
  const char * name,
  const std::vector<const char *> &labels,
  size_t default_index
 )
 {
  options.emplace_back(name, labels, default_index);
 
  for (size_t i = 0; i < args.size() - 1; i++)
  {
   if (args[i].option == name)
   {
    args[i].used = true;
    args[i + 1].used = true;
    update_index();
 
    for (int j = int(labels.size()); --j >= 0;)
     if (labels[j] == args[i + 1].s)
      return size_t(j);
 
    throw Exception
    (
     std::string("invalid value for option ") + std::string(args[i].s) +
     ": " + std::string(args[i + 1].s)
    );
   }
  }
 
  return default_index;
 }
 
 std::string_view Arguments::get_next()
 {
  return get_next(nullptr);
 }
 
 std::string_view Arguments::get_next(const char * parameter)
 {
  if (parameter)
   options.emplace_back(parameter);
 
  if (index < argc)
   return use_index();
  else
  {
   missing_arg = true;
   return std::string_view{};
  }
 }
 
 bool Arguments::peek(const char *s)
 {
  if (index < argc && args[index].s == s)
  {
   use_index();
   return true;
  }
  else
   return false;
 }
 
 void Arguments::add_parameter(const char * parameter)
 {
  options.emplace_back(parameter);
 }
 
 std::ostream &Arguments::print_help(std::ostream &out) const
 {
  out << "usage: " << args[0].s;
 
  for (const auto &option: options)
  {
   if (option.name.data())
   {
    out << " [--";
    out << option.name;
    if (option.parameter.data())
     out << " <" << option.parameter << '>';
    else if (option.labels)
    {
     for (size_t i = 0; i < option.labels->size(); i++)
     {
      out << (i > 0 ? '|' : ' ');
      out << option.labels->at(i);
      if (size_t(option.default_index) == i)
       out << '*';
     }
    }
    out << ']';
   }
   else if (option.parameter.data())
    out << ' ' << option.parameter;
  }
 
  out << '\n';
 
  return out;
 }
}