Kylin/HttpProxy/TemplateSegmentRule.h

#ifndef __TEMPLATESEGMENTRULE_H__
#define __TEMPLATESEGMENTRULE_H__

#include <boost/url/error_types.hpp>
#include <boost/url/grammar/delim_rule.hpp>
#include <boost/url/grammar/optional_rule.hpp>
#include <boost/url/grammar/range_rule.hpp>
#include <boost/url/grammar/tuple_rule.hpp>
#include <boost/url/pct_string_view.hpp>
#include <boost/url/string_view.hpp>

class TemplateSegment {
    friend class TemplateSegmentRule;

public:
    enum class Modifier {
        None,
        Optional, // {id?}
        Star,     // {id*}
        Plus      // {id+}
    };

public:
    bool isLiteral() const;
    bool isStar() const;
    bool isPlus() const;
    bool isOptional() const;
    bool hasModifier() const;
    boost::core::string_view id() const;
    boost::core::string_view string() const;
    bool match(boost::urls::pct_string_view segement) const;
    bool operator==(const TemplateSegment &other) const;

    // segments have precedence:
    //     - literal
    //     - unique
    //     - optional
    //     - plus
    //     - star
    bool operator<(const TemplateSegment &other) const;

private:
    Modifier modifier = Modifier::None;
    std::string m_string;
    bool m_isLiteral = true;
};

class TemplateSegmentRule {
public:
    using value_type = TemplateSegment;
    boost::urls::result<value_type> parse(char const *&iterator, char const *end) const noexcept;
};

constexpr auto templateSegmentRule = TemplateSegmentRule{};

constexpr auto templatePathRule = boost::urls::grammar::tuple_rule(
    boost::urls::grammar::squelch(boost::urls::grammar::optional_rule(boost::urls::grammar::delim_rule('/'))),
    boost::urls::grammar::range_rule(
        templateSegmentRule,
        boost::urls::grammar::tuple_rule(boost::urls::grammar::squelch(boost::urls::grammar::delim_rule('/')),
                                         templateSegmentRule)));

#endif // __TEMPLATESEGMENTRULE_H__