sygbp-osc_string_constants.hpp

#pragma once
/*
Copyright 2023 Travis J. West, https://traviswest.ca, Input Devices and Music Interaction Laboratory
(IDMIL), Centre for Interdisciplinary Research in Music Media and Technology
(CIRMMT), McGill University, Montréal, Canada, and Univ. Lille, Inria, CNRS,
Centrale Lille, UMR 9189 CRIStAL, F-59000 Lille, France
 
SPDX-License-Identifier: MIT
*/
 
#include <array>
#include <concepts>
#include "sygac-tuple.hpp"
#include "sygac-components.hpp"
#include "sygac-endpoints.hpp"
#include "sygbp-spelling.hpp"
 
namespace sygaldry { namespace sygbp {
 
template<typename> struct osc_path_length : std::integral_constant<std::size_t, 0> {};
template<template<typename...>typename L, typename ... Path>
struct osc_path_length<L<Path...>>
: std::integral_constant<std::size_t, (name_length<std::decay_t<Path>>() + ...) + sizeof...(Path)> {};
template<typename T>
constexpr std::size_t osc_type_string_length()
{
    if constexpr (array_like<value_t<T>>)
    {
        constexpr auto length = size<value_t<T>>() + 1;
        constexpr auto remainder = length % 4;
        constexpr auto padding = 4 - remainder;
        return length + padding;
    }
    else return 4;
}
 
template<typename> struct osc_path;
template<template<typename...>typename L, typename ... Path>
struct osc_path<L<Path...>>
{
    static constexpr size_t N = osc_path_length<L<std::decay_t<Path>...>>() + 1; // + 1 for null terminator
    static constexpr std::array<char, N> value = []()
    {
        L<std::decay_t<Path>...> path;
        std::array<char, N> ret;
        std::size_t write_pos = 0;
        auto copy_one = [&]<typename T>(T)
        {
           ret[write_pos++] = '/';
            for (std::size_t i = 0; i < name_length<T>(); ++i)
            {
                ret[write_pos++] = snake_case_v<T>[i];
            }
        };
        tpl::apply([&]<typename ... Ts>(Ts... ts)
        {
            (copy_one(ts), ...);
        }, path);
        ret[write_pos] = 0;
        return ret;
    }();
};
 
template<typename T, typename Components>
constexpr const char * osc_path_v = osc_path<path_t<T,Components>>::value.data();
 
template<typename T>
struct osc_type_string
{
    static constexpr size_t N = osc_type_string_length<T>();
    static constexpr std::array<char, N> value = []()
    {
        std::array<char, N> ret{0};
        ret[0] = ',';
 
        if constexpr (Bang<T>) return ret;
 
        char tag;
        if constexpr (std::integral<element_t<T>>) tag = 'i';
        else if constexpr (std::floating_point<element_t<T>>) tag = 'f';
        else if constexpr (string_like<element_t<T>>) tag = 's';
        else return ret; // this should never happen
 
        if constexpr (array_like<value_t<T>>)
            for (std::size_t i = 0; i < size<value_t<T>>(); ++i)
                ret[1 + i] = tag;
        else ret[1] = tag;
        return ret;
    }();
};
 
template<typename T> constexpr const char * osc_type_string_v = osc_type_string<T>::value.data();
 
//template<typename T, typename Components>
//constexpr bool osc_match_pattern(const char * p)
//{
//    return osc_match_pattern(p, osc_path_v<T, Components>);
//}
 
} }