%% hangulmath.sty
%% Hangul jamo as math symbols.
%%
%% Copyright (C) 2026 Inkyu Park <icpark00@gmail.com>
%%
%% This work may be distributed and/or modified under the
%% conditions of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%% The latest version of this license is in
%%   https://www.latex-project.org/lppl.txt
%% and version 1.3c or later is part of all distributions of LaTeX
%% version 2008 or later.
%%
%% This work has the LPPL maintenance status `maintained'.
%% The Current Maintainer of this work is Inkyu Park.
%%
%% This work consists of the files hangulmath.sty,
%% hangulmath-metrics.def, hangulmath-metrics.py and
%% hangulmath-doc.tex. The fonts hangulmath-sans.otf and
%% hangulmath-sans-light.otf are distributed under the SIL Open Font
%% License 1.1 (see OFL.txt).
%%
\NeedsTeXFormat{LaTeX2e}[2022/06/01]
\ProvidesPackage{hangulmath}[2026/10/10 v0.5 Hangul jamo as math symbols]

\RequirePackage{iftex}
\RequireTUTeX
\RequirePackage{fontspec}
\RequirePackage{amstext}% \text: scales correctly in sub/superscripts
\RequirePackage{graphicx}% \scalebox for operator forms

% ---------------------------------------------------------------
% Options
%   font        = <font name or file>  symbol font
%                 (default: bundled hangulmath-sans.otf)
%   opfont      = <font name or file>  font for large operators
%                 (default: bundled hangulmath-sans-light.otf)
%   metrics     = <file name>          glyph metrics (.def), made by
%                 hangulmath-metrics.py; required for non-default fonts
%   scale       = <number>             (default: from metrics file)
%   sidebearing = <number, em>         space left/right of each glyph
% ---------------------------------------------------------------
\def\hm@bundledfont{hangulmath-sans.otf}
\def\hm@bundledopfont{hangulmath-sans-light.otf}
\def\hm@fontname{\hm@bundledfont}
\def\hm@opfontname{\hm@bundledopfont}
\def\hm@metricsfile{hangulmath-metrics}
\def\hm@scale{}
\def\hm@sb{0.06}
\DeclareKeys[hangulmath]{
  font.store        = \hm@fontname,
  opfont.store      = \hm@opfontname,
  metrics.store     = \hm@metricsfile,
  scale.store       = \hm@scale,
  sidebearing.store = \hm@sb,
}
\ProcessKeyOptions[hangulmath]

% ---------------------------------------------------------------
% Glyph metrics
%   \hm@metric{<hex>}{<left bearing>}{<right bearing>}  (in em)
%   Missing metrics -> glyph is used with the font's own spacing.
% ---------------------------------------------------------------
\def\hm@baseshift{0}
\def\hm@defaultscale{1}
\newcommand\hm@metric[3]{%
  \@namedef{hm@L@#1}{#2}\@namedef{hm@R@#1}{#3}}
\newcommand\hm@get[2]{%
  \ifcsname hm@#1@#2\endcsname\@nameuse{hm@#1@#2}\else 0\fi}
\InputIfFileExists{\hm@metricsfile.def}{}{%
  \PackageWarningNoLine{hangulmath}{%
    Metrics file `\hm@metricsfile.def' not found.\MessageBreak
    Glyphs are not trimmed or aligned to the baseline.\MessageBreak
    Run hangulmath-metrics.py for your font}}
\ifx\hm@scale\@empty \let\hm@scale\hm@defaultscale \fi

% ---------------------------------------------------------------
% Fonts
%   A requested font that is not installed falls back to the
%   bundled font with a warning, so documents always compile.
% ---------------------------------------------------------------
\newcommand\hm@loadfont[3]{% #1 family cs, #2 requested, #3 bundled
  \edef\hm@tmp{#2}%
  \IfFontExistsTF{\hm@tmp}{}{%
    \PackageWarningNoLine{hangulmath}{%
      Font `\hm@tmp' not found;\MessageBreak using bundled `#3'}%
    \def\hm@tmp{#3}}%
  \expandafter\setfontfamily\expandafter#1\expandafter{\hm@tmp}[Scale=\hm@scale]}
\newcommand\hangulmathfont[1]{\hm@loadfont\hm@font{#1}{\hm@bundledfont}}
\newcommand\hangulmathopfont[1]{\hm@loadfont\hm@opfont{#1}{\hm@bundledopfont}}
\hangulmathfont{\hm@fontname}
\hangulmathopfont{\hm@opfontname}
\let\hm@curfont\hm@font

% ---------------------------------------------------------------
% Core symbol builder
%   - trims side bearings to the ink, adds \hm@sb on each side
%   - lowers by \hm@baseshift so consonants sit on the baseline
%   - always upright; \ensuremath allows use in running text
% ---------------------------------------------------------------
\newcommand\hm@sym[1]{%
  \ensuremath{\mathord{\text{\normalfont\hm@curfont
    \lower\hm@baseshift em\hbox{%
      \kern\dimexpr\hm@sb em-\hm@get{L}{#1}em\relax
      \symbol{"#1}%
      \kern\dimexpr\hm@sb em-\hm@get{R}{#1}em\relax}}}}}

% \hm@define{<official>}{<alias>}{<hex code>}
%   \newcommand raises an error if a name is already taken.
\newcommand\hm@define[3]{%
  \expandafter\newcommand\csname #1\endcsname{\hm@sym{#3}}%
  \if\relax\detokenize{#2}\relax\else
    \expandafter\newcommand\csname #2\endcsname{\hm@sym{#3}}%
  \fi}

% ---------------------------------------------------------------
% Consonants  (official RR name, 4-letter alias, Unicode)
% ---------------------------------------------------------------
\hm@define{giyeok}{giug}{3131}% ㄱ
\hm@define{nieun} {niun}{3134}% ㄴ
\hm@define{digeut}{diud}{3137}% ㄷ
\hm@define{rieul} {liul}{3139}% ㄹ
\hm@define{mieum} {mium}{3141}% ㅁ
\hm@define{bieup} {biub}{3142}% ㅂ
\hm@define{siot}  {sius}{3145}% ㅅ
\hm@define{ieung} {iung}{3147}% ㅇ
\hm@define{jieut} {jiuj}{3148}% ㅈ
\hm@define{chieut}{ciuc}{314A}% ㅊ
\hm@define{kieuk} {kiuk}{314B}% ㅋ
\hm@define{tieut} {tiut}{314C}% ㅌ
\hm@define{pieup} {piup}{314D}% ㅍ
\hm@define{hieut} {hiuh}{314E}% ㅎ

% ---------------------------------------------------------------
% Vowels  (sound + trailing h)
% ---------------------------------------------------------------
\hm@define{ah}  {}{314F}% ㅏ
\hm@define{yah} {}{3151}% ㅑ
\hm@define{eoh} {}{3153}% ㅓ
\hm@define{yeoh}{}{3155}% ㅕ
\hm@define{oh}  {}{3157}% ㅗ
\hm@define{yoh} {}{315B}% ㅛ
\hm@define{uh}  {}{315C}% ㅜ
\hm@define{yuh} {}{3160}% ㅠ
\hm@define{euh} {}{3161}% ㅡ
\hm@define{ih}  {}{3163}% ㅣ

% ---------------------------------------------------------------
% Double consonants  (official name, alias = first letter doubled)
% ---------------------------------------------------------------
\hm@define{ssanggiyeok}{ggiug}{3132}% ㄲ
\hm@define{ssangdigeut}{ddiud}{3138}% ㄸ
\hm@define{ssangbieup} {bbiub}{3143}% ㅃ
\hm@define{ssangsiot}  {ssius}{3146}% ㅆ
\hm@define{ssangjieut} {jjiuj}{3149}% ㅉ

% ---------------------------------------------------------------
% Compound vowels  (sound + trailing h; glide w written as u)
% ---------------------------------------------------------------
\hm@define{aeh} {}{3150}% ㅐ
\hm@define{yaeh}{}{3152}% ㅒ
\hm@define{eh}  {}{3154}% ㅔ
\hm@define{yeh} {}{3156}% ㅖ
\hm@define{uah} {}{3158}% ㅘ
\hm@define{uaeh}{}{3159}% ㅙ
\hm@define{oeh} {}{315A}% ㅚ
\hm@define{ueoh}{}{315D}% ㅝ
\hm@define{ueh} {}{315E}% ㅞ
\hm@define{uih} {}{315F}% ㅟ
\hm@define{euih}{}{3162}% ㅢ

% ---------------------------------------------------------------
% Operator forms  (work with any symbol, e.g. \hangulsum\tiut)
%   \hangulsum{<sym>}  large, limits below/above in display (like \sum)
%   \hangulint{<sym>}  large, limits at the side           (like \int)
%   \hangullim{<sym>}  normal size, limits below in display (like \lim)
%   Large forms use the lighter operator font so that scaling up
%   does not make the strokes too heavy.
%   Sizes: \hangulopscale{<display>}{<text>}
% ---------------------------------------------------------------
\newcommand\hm@opdisplay{2.0}
\newcommand\hm@optext{1.3}
\newcommand\hangulopscale[2]{%
  \renewcommand\hm@opdisplay{#1}\renewcommand\hm@optext{#2}}
\newcommand\hm@opbox[2]{% #1 scale, #2 symbol
  \vcenter{\hbox{\let\hm@curfont\hm@opfont
    \scalebox{#1}{$\m@th#2$}}}}
\newcommand\hm@bigop[1]{\mathop{\mathchoice
  {\hm@opbox{\hm@opdisplay}{#1}}
  {\hm@opbox{\hm@optext}{#1}}
  {\vcenter{\hbox{$\m@th\scriptstyle#1$}}}
  {\vcenter{\hbox{$\m@th\scriptscriptstyle#1$}}}}}
\newcommand\hangulsum[1]{\hm@bigop{#1}\displaylimits}
\newcommand\hangulint[1]{\hm@bigop{#1}\nolimits}
\newcommand\hangullim[1]{\mathop{#1}\displaylimits}

\endinput