#ifndef PROGRAM_OPTIONS_H
#define PROGRAM_OPTIONS_H

/* wraps boost options_description as printable_opts - show the options values used as well as defaults in usage or log messages.  boost program options library lacks any concept of printing configured values; it only supports parsing them from strings */

#ifdef _WIN32
#include <iso646.h>
#endif
#include <boost/program_options.hpp>
#include <boost/function.hpp>
#include <boost/shared_ptr.hpp>
#include <stdexcept>
#include <iosfwd>


// change --opt-name=x --opt_name=x for all strings x.  danger: probably the argv from int main isn't supposed to be modified?
inline int arg_minusto_underscore(char *s) {
  if (!*s || *s++ != '-') return 0;
  if (!*s || *s++ != '-') return 0;
  int chars_replaced=0;
  for(;*s;++s) {
    if (*s=='=')
      break;
    if (*s=='-') {
      *s='_';
      ++chars_replaced;
    }
  }
  return chars_replaced;
}

inline
int argv_minus_to_underscore(int argc, char **argv) {
  int chars_replaced=0;
  for (int i=1;i<argc;++i) {
    chars_replaced+=arg_minusto_underscore(argv[i]);
  }
  return chars_replaced;
}

template <class T>
boost::program_options::typed_value<T>*
defaulted_value(T *v)
{
  return boost::program_options::value<T>(v)->default_value(*v);
}

inline void program_options_fatal(std::string const& msg) {
  throw std::runtime_error(msg);
}


inline std::string const& get_single_arg(boost::any& v,std::vector<std::string> const& values)
{
  boost::program_options::validators::check_first_occurrence(v);
  return boost::program_options::validators::get_single_string(values);
}

template <class I>
void must_complete_read(I &in,std::string const& msg="Couldn't parse")
{
  char c;
  if (in.bad())
    program_options_fatal(msg + " - failed input");
  if (in >> c)
    program_options_fatal(msg + " - got extra char: " + std::string(c,1));
}

template <class Ostream>
struct any_printer  : public boost::function<void (Ostream &,boost::any const&)>
{
  typedef boost::function<void (Ostream &,boost::any const&)> F;

  template <class T>
  struct typed_print
  {
    void operator()(Ostream &o,boost::any const& t) const
    {
      o << *boost::any_cast<T const>(&t);
    }
  };

  template <class T>
  static
  void typed_print_template(Ostream &o,boost::any const& t)
  {
    o << *boost::any_cast<T const>(&t);
  }

  any_printer() {}

  any_printer(const any_printer& x)
    : F(static_cast<F const&>(x))
  {}

  template <class T>
  explicit any_printer(T const*) : F(typed_print<T>()) {
  }

  template <class T>
  void set()
  {
    F f(typed_print<T>());
    swap(f);
  }
};

// have to wrap regular options_description and store our own tables because
// author didn't make enough stuff protected/public or add a virtual print
// method to value_semantic
template <class Ostream>
struct printable_options_description
  : public boost::program_options::options_description
{
  typedef printable_options_description<Ostream> self_type;
  typedef boost::program_options::options_description options_description;
  typedef boost::program_options::option_description option_description;
  typedef boost::shared_ptr<self_type> group_type;
  typedef std::vector<group_type > groups_type;

  struct printable_option
  {
    typedef boost::shared_ptr<option_description> OD;

    any_printer<Ostream> print;
    OD od;
    bool in_group;

    std::string const& name()
    { return od->long_name(); }

    std::string const& description()
    { return od->description(); }

    std::string const& vmkey()
    {
      return od->key(name());
    }
    template <class T>
    printable_option(T *tag, OD const& od) : print(tag),od(od),in_group(false) {}
    printable_option() : in_group(false) {}
  };
  typedef std::vector<printable_option > options_type;
  BOOST_STATIC_CONSTANT(unsigned,default_linewrap=80); // options_description::m_default_line_length
  printable_options_description(unsigned line_length = default_linewrap) :
    options_description(line_length) {}

  printable_options_description(const std::string& caption,
                                unsigned line_length = default_linewrap)
    : options_description(caption,line_length), caption(caption) {}

  self_type &add_options()
  { return *this; }

  template <class T,class C>
  self_type &
  operator()(char const* name,
             boost::program_options::typed_value<T,C> *val,
             char const*description=NULL)
  {
    printable_option opt((T *)0,simple_add(name,val,description));
    pr_options.push_back(opt);
    return *this;
  }

  self_type&
  add(self_type const& desc)
  {
    options_description::add(desc);
    groups.push_back(group_type(new self_type(desc)));
    for (typename options_type::const_iterator i=desc.pr_options.begin(),e=desc.pr_options.end();
         i!=e;++i) {
      pr_options.push_back(*i);
      pr_options.back().in_group=true;
    }
    return *this;
  }

  void print_option(Ostream &o,
                    printable_option &opt,
                    boost::program_options::variable_value const & var,
                    bool only_value=false)
  {
    using namespace boost;
    using namespace boost::program_options;
    using namespace std;
    string const& name=opt.name();
    if (!only_value) {
      if (var.defaulted())
        o << "#DEFAULTED# ";
      if (var.empty()) {
        o << "#EMPTY# "<<name;
        return;
      }
      o << name<<" = ";
    }
    opt.print(o,var.value());
  }

  enum { SHOW_DEFAULTED=0x1
         , SHOW_EMPTY=0x2
         , SHOW_DESCRIPTION=0x4
         ,  SHOW_HIERARCHY=0x8
         ,  SHOW_ALL=0x0FFF
         ,  SHOW_HELP=0x1000
  };

  void print(Ostream &o,
             boost::program_options::variables_map &vm,
             int show_flags=SHOW_DESCRIPTION & SHOW_DEFAULTED & SHOW_HIERARCHY)
  {
    const bool show_defaulted=bool(show_flags & SHOW_DEFAULTED);
    const bool show_description=bool(show_flags & SHOW_DESCRIPTION);
    const bool hierarchy=bool(show_flags & SHOW_HIERARCHY);
    const bool show_empty=bool(show_flags & SHOW_EMPTY);
    const bool show_help=bool(show_flags & SHOW_HELP);

    using namespace boost::program_options;
    using namespace std;
    o << "### " << caption << endl;
    for (typename options_type::iterator i=pr_options.begin(),e=pr_options.end();
         i!=e;++i) {
      printable_option & opt=*i;
      if (!show_help && opt.name()=="help")
        continue;
      if (hierarchy and opt.in_group)
        continue;
      variable_value const & var=vm[opt.vmkey()];
      if (var.defaulted() && !show_defaulted)
        continue;
      if (var.empty() && !show_empty)
        continue;
      if (show_description)
        o << "# " << opt.description() << endl;
      print_option(o,opt,var);
      o << endl;
    }
    o << endl;
    if (hierarchy)
      for (typename groups_type::iterator i=groups.begin(),e=groups.end();
           i!=e;++i)
        (*i)->print(o,vm,show_flags);
  }

/// parses arguments, then stores/notifies from opts->vm.  returns unparsed
/// options and positional arguments, but if not empty, throws exception unless
/// allow_unrecognized_positional is true
  std::vector<std::string>
  parse_options(int argc,char **argv,
                boost::program_options::variables_map &vm,
                boost::program_options::positional_options_description *po=NULL,
                bool allow_unrecognized_positional=false,
                bool allow_unrecognized_opts=false)
  {
    using namespace boost::program_options;
    using namespace std;
    command_line_parser cl(argc,argv);
    cl.options(*this);
    if (po)
      cl.positional(*po);
    if (allow_unrecognized_opts)
      cl.allow_unregistered();
    parsed_options parsed=cl.run();
    vector<string> unparsed=collect_unrecognized(parsed.options,
                                                 po ? exclude_positional : include_positional);
    if (!allow_unrecognized_positional) {
      if (!unparsed.empty())
        program_options_fatal("Unrecognized argument: "+unparsed.front());
    }
    store(parsed,vm);
    notify(vm);
    return unparsed;
  }

  std::vector<std::string>
  parse_options(int argc,char const*argv[],
                boost::program_options::variables_map &vm,
                boost::program_options::positional_options_description *po=NULL,
                bool allow_unrecognized_positional=false,
                bool allow_unrecognized_opts=false)
  {
    return parse_options(argc,const_cast<char **>(argv),vm,po
                         ,allow_unrecognized_positional,allow_unrecognized_opts);
  }

private:
  groups_type groups;
  options_type pr_options;
  std::string caption;
  boost::shared_ptr<option_description>
  simple_add(const char* name,
             const boost::program_options::value_semantic* s,
             const char * description = NULL)
  {
    typedef option_description OD;
    boost::shared_ptr<OD> od(
      (description ? new OD(name,s,description) : new OD(name,s))
      );
    options_description::add(od);
    return od;
  }
};

typedef printable_options_description<std::ostream> printable_opts;



#endif