program_options/src/options_description.cpp

// Copyright Vladimir Prus 2002-2004.
// Copyright Bertolt Mildner 2004.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt
// or copy at http://www.boost.org/LICENSE_1_0.txt)


#define BOOST_PROGRAM_OPTIONS_SOURCE
#include <boost/program_options/config.hpp>
#include <boost/program_options/options_description.hpp>
// FIXME: this is only to get multiple_occureces class
// should move that to a separate headers.
#include <boost/program_options/parsers.hpp>


#include <boost/lexical_cast.hpp>
#include <boost/tokenizer.hpp>
#include <boost/detail/workaround.hpp>
#include <boost/throw_exception.hpp>

#include <cassert>
#include <climits>
#include <cstring>
#include <cstdarg>
#include <sstream>
using namespace std;

namespace boost { namespace program_options {

    option_description::option_description()
    {
    }
    
    option_description::
    option_description(const char* name,
                       const value_semantic* s)
    : m_value_semantic(s)
    {
        this->name(name);
    }
                                           

    option_description::
    option_description(const char* name,
                       const value_semantic* s,
                       const char* description)
    : m_description(description), m_value_semantic(s)
    {
        this->name(name);
    }

    option_description::~option_description()
    {
    }

    option_description&
    option_description::name(const char* _name)
    {
        std::string name(_name);
        string::size_type n = name.find(',');
        if (n != string::npos) {
            assert(n == name.size()-2);
            m_long_name = name.substr(0, n);
            m_short_name = name.substr(n+1,1);
        } else {
            m_long_name = name;
        }
        return *this;
    }

    const std::string&
    option_description::short_name() const
    {
        return m_short_name;
    }

    const std::string&
    option_description::long_name() const
    {
        return m_long_name;
    }

    const std::string&
    option_description::description() const
    {
        return m_description;
    }

    shared_ptr<const value_semantic>
    option_description::semantic() const
    {
        return m_value_semantic;
    }
    
    std::string 
    option_description::format_name() const
    {
        if (!short_name().empty())
            return string("-").append(short_name()).append(" [ --").
            append(long_name()).append(" ]");
        else
            return string("--").append(long_name());
    }

    std::string 
    option_description::format_parameter() const
    {
        if (!m_value_semantic->is_zero_tokens())
            return m_value_semantic->name();
        else
            return "";
    }

    options_description_easy_init::
    options_description_easy_init(options_description* owner)
    : owner(owner)
    {}

    options_description_easy_init&
    options_description_easy_init::
    operator()(const char* name,
               const char* description)
    {
        // Create untypes semantic which accepts zero tokens: i.e. 
        // no value can be specified on command line.
        // FIXME: does not look exception-safe
        shared_ptr<option_description> d(
            new option_description(name, new untyped_value(true), description));

        owner->add(d);
        return *this;
    }

    options_description_easy_init&
    options_description_easy_init::
    operator()(const char* name,
               const value_semantic* s)
    {
        shared_ptr<option_description> d(new option_description(name, s));
        owner->add(d);
        return *this;
    }

    options_description_easy_init&
    options_description_easy_init::
    operator()(const char* name,
               const value_semantic* s,
               const char* description)
    {
        shared_ptr<option_description> d(new option_description(name, s, description));

        owner->add(d);
        return *this;
    }

    options_description::options_description(unsigned line_length)
    : m_line_length(line_length)
    {}

    options_description::options_description(const string& caption,
                                             unsigned line_length)
    : m_caption(caption), m_line_length(line_length)
    {}

    void
    options_description::add(shared_ptr<option_description> desc)
    {
        const string& s = desc->short_name();
        const string& l = desc->long_name();
        assert(!s.empty() || !l.empty());
        if (!s.empty())
            if (name2index.count("-" + s) != 0)
                throw_exception(
                    duplicate_option_error(
                        "Short name '" + s + "' is already present"));
            else
                name2index["-" + s] = options.size();
        if (!l.empty())
            if (name2index.count(s) != 0)
                throw_exception(
                    duplicate_option_error(
                        "Long name '" + s + "' is already present"));
            else
                name2index[l] = options.size();
        options.push_back(desc);
        belong_to_group.push_back(false);
    }

    options_description&
    options_description::add(const options_description& desc)
    {
        shared_ptr<options_description> d(new options_description(desc));
        groups.push_back(d);

        for (size_t i = 0; i < desc.options.size(); ++i) {
            add(desc.options[i]);
            belong_to_group.back() = true;
        }

        return *this;
    }

    options_description_easy_init
    options_description::add_options()
    {       
        return options_description_easy_init(this);
    }

    unsigned
    options_description::count(const std::string& name) const
    {
        return name2index.count(name);
    }

    unsigned
    options_description::count_approx(const std::string& prefix) const
    {
        approximation_range er = find_approximation(prefix);
        return distance(er.first, er.second);
    }

    const option_description&
    options_description::find(const std::string& name) const
    {
        assert(this->count(name) != 0);
        return *options[name2index.find(name)->second];
    }

    const option_description&
    options_description::find_approx(const std::string& prefix) const
    {
        approximation_range er = find_approximation(prefix);
        assert(distance(er.first, er.second) == 1);
        return *options[er.first->second];
    }

    std::set<std::string>
    options_description::keys() const
    {
        set<string> result;
        for (map<string, int>::const_iterator i = name2index.begin();
             i != name2index.end();
             ++i)
            result.insert(i->first);
        return result;
    }

    std::set<std::string>
    options_description::primary_keys() const
    {
        set<string> result;
        for (size_t i = 0; i < options.size(); ++i)
            if (options[i]->long_name().empty())
                result.insert("-" + options[i]->short_name());
            else
                result.insert(options[i]->long_name());
        return result;
    }

    std::set<std::string>
    options_description::approximations(const std::string& prefix) const
    {
        approximation_range er = find_approximation(prefix);
        set<string> result;
        for (name2index_iterator i = er.first; i != er.second; ++i)
            result.insert(i->first);
        return result;
    }

    options_description::approximation_range
    options_description::find_approximation(const std::string& prefix) const
    {
        name2index_iterator b = name2index.lower_bound(prefix);
        name2index_iterator e = name2index.upper_bound(prefix + char(CHAR_MAX));
        return make_pair(b, e);
    }


    BOOST_PROGRAM_OPTIONS_DECL
    std::ostream& operator<<(std::ostream& os, const options_description& desc)
    {
        desc.print(os);
        return os;
    }

    namespace {

        void format_paragraph(std::ostream& os,
                              std::string par,
                              unsigned first_column_width,
                              unsigned line_length)
        {                    
            // index of tab (if present) is used as additional indent relative
            // to first_column_width if paragrapth is spanned over multiple
            // lines if tab is not on first line it is ignored
            string::size_type par_indent = par.find('\t');

            if (par_indent == string::npos)
            {
                par_indent = 0;
            }
            else
            {
                // only one tab per paragraph allowed
                if (count(par.begin(), par.end(), '\t') > 1)
                {
                    throw_exception(program_options::error(
                        "Only one tab per paragraph is allowed"));
                }
          
                // erase tab from string
                par.erase(par_indent, 1);

                // this assert may fail due to user error or 
                // environment conditions!
                assert(par_indent < (line_length - first_column_width));

                // ignore tab if not on first line
                if (par_indent >= (line_length - first_column_width))
                {
                    par_indent = 0;
                }            
            }
          
            if (par.size() < (line_length - first_column_width))
            {
                os << par;
            }
            else
            {
                string::const_iterator       line_begin = par.begin();
                const string::const_iterator par_end = par.end();

                bool first_line = true; // of current paragraph!
            
                unsigned indent = first_column_width;
            
                while (line_begin < par_end)  // paragraph lines
                {
                    if (!first_line)
                    {
                        // trimm leading single spaces
                        // if (firstchar == ' ') &&
                        //    ((exists(firstchar + 1) && (firstchar + 1 != ' '))
                        if ((*line_begin == ' ') &&
                            ((line_begin + 1 < par_end) &&
                             (*(line_begin + 1) != ' ')))
                        {
                            line_begin += 1;  // line_begin != line_end
                        }
                    }

                    string::const_iterator line_end;
                
                    if (line_begin + (line_length - indent) > par_end)
                    {
                        line_end = par_end;
                    }
                    else
                    {
                        line_end = line_begin + (line_length - indent);
                    }
            
                    // prevent chopped words
                    // if (lastchar != ' ') &&
                    //    ((exists(lastchar + 1) && (lastchar + 1 != ' '))
                    if ((*(line_end - 1) != ' ') &&
                        ((line_end < par_end) && (*line_end != ' ')))
                    {
                        // find last ' ' in the second half of the current paragraph line
                        string::const_iterator last_space =
                            find(reverse_iterator<string::const_iterator>(line_end - 1),
                                 reverse_iterator<string::const_iterator>(line_begin - 1),
                                 ' ')
                            .base();
                
                        if (last_space != line_begin - 1)
                        {                 
                            // is last_space within the second half ot the 
                            // current line
                            if (unsigned(distance(last_space, line_end)) < 
                                (line_length - indent) / 2)
                            {
                                line_end = last_space;
                            }
                        }                                                
                    } // prevent chopped words
             
                    // write line to stream
                    copy(line_begin, line_end, ostream_iterator<char>(os));
              
                    if (first_line)
                    {
                        indent = first_column_width + par_indent;
                        first_line = false;
                    }

                    // more lines to follow?
                    if (line_end != par_end)
                    {
                        os << '\n';
                
                        for(unsigned pad = indent; pad > 0; --pad)
                        {
                            os.put(' ');
                        }                                                        
                    }
              
                    // next line starts after of this line
                    line_begin = line_end;              
                } // paragraph lines
            }          
        }                              
        
        void format_description(std::ostream& os,
                                const std::string& desc, 
                                unsigned first_column_width,
                                unsigned line_length)
        {
            // we need to use one char less per line to work correctly if actual
            // console has longer lines
            assert(line_length > 1);
            if (line_length > 1)
            {
                --line_length;
            }

            // line_length must be larger than first_column_width
            // this assert may fail due to user error or environment conditions!
            assert(line_length > first_column_width);

            // Note: can't use 'tokenizer' as name of typedef -- borland
            // will consider subsequence uses of 'tokenizer' as uses of
            // boost::tokenizer, not typedef.
            typedef boost::tokenizer<boost::char_separator<char> > tok;
          
            tok paragraphs(
                desc,
                char_separator<char>("\n", "", boost::keep_empty_tokens));
          
            tok::const_iterator       par_iter = paragraphs.begin();                
            const tok::const_iterator par_end = paragraphs.end();

            while (par_iter != par_end)  // paragraphs
            {
                format_paragraph(os, *par_iter, first_column_width, 
                                 line_length);
            
                ++par_iter;
            
                // prepair next line if any
                if (par_iter != par_end)
                {
                    os << '\n';
              
                    for(unsigned pad = first_column_width; pad > 0; --pad)
                    {
                        os.put(' ');
                    }                    
                }            
            }  // paragraphs
        }
    
        void format_one(std::ostream& os, const option_description& opt, 
                        unsigned first_column_width, unsigned line_length)
        {
            stringstream ss;
            ss << "  " << opt.format_name() << ' ' << opt.format_parameter();
            
            // Don't use ss.rdbuf() since g++ 2.96 is buggy on it.
            os << ss.str();

            if (!opt.description().empty())
            {
                for(unsigned pad = first_column_width - ss.str().size(); 
                    pad > 0; 
                    --pad)
                {
                    os.put(' ');
                }
            
                format_description(os, opt.description(),
                                   first_column_width, line_length);
            }
        }
    }

    void 
    options_description::print(std::ostream& os) const
    {
        if (!m_caption.empty())
            os << m_caption << ":\n";

        /* Find the maximum width of the option column */
        unsigned width(23);
        unsigned i; // vc6 has broken for loop scoping
        for (i = 0; i < options.size(); ++i)
        {
            const option_description& opt = *options[i];
            stringstream ss;
            ss << "  " << opt.format_name() << ' ' << opt.format_parameter();
            width = max(width, static_cast<unsigned>(ss.str().size()));            
        }
        
        /* add an additional space to improve readability */
        ++width;
            
        /* The options formatting style is stolen from Subversion. */
        for (i = 0; i < options.size(); ++i)
        {
            if (belong_to_group[i])
                continue;

            const option_description& opt = *options[i];

            format_one(os, opt, width, m_line_length);

            os << "\n";
        }

        for (unsigned j = 0; j < groups.size(); ++j) {            
            os << "\n" << *groups[j];
        }
    }

}}