% Babelbidi: Bidi extensions for Babel.
%
% Copyright (C) 2026 Amer Amikhteh
%
% This file is part of the Babelbidi package.
%
% This work is free software: you may redistribute it and/or modify
% it under the terms of the LaTeX Project Public License as published
% by the LaTeX Project, either version 1.3c of the License, or
% (at your option) any later version.
%
% This work is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
%
% The full license text is available at:
% https://www.latex-project.org/lppl/
%
% This work is "maintained" by Amer Amikhteh.
%
% The current maintainer of this work is Amer Amikhteh.

\ProvidesFile{babelbidi-api.def}
[2026/10/09 v0.1.0 Bidi API for Babelbidi]

\makeatletter


% ------------------------------------------
% Determining text direction
% ------------------------------------------

\providecommand{\if@RTL}{\ifnum\bbl@thetextdir>\z@}
\providecommand{\@RTLtrue}{\chardef\bbl@thetextdir\@ne}
\providecommand{\@RTLfalse}{\chardef\bbl@thetextdir\z@}

\providecommand{\bbd@main@dir}{0}

\providecommand{\if@RTLmain}{%
    \ifnum\bbd@main@dir>\z@
}

\providecommand{\@RTLmaintrue}{%
    \gdef\bbd@main@dir{1}%
}

\providecommand{\@RTLmainfalse}{%
    \gdef\bbd@main@dir{0}%
}

\AddToHook{begindocument}{%
    \ifnum\bbl@thetextdir>\z@
        \@RTLmaintrue
    \else
        \@RTLmainfalse
    \fi
}%

% ------------------------------------------
% basic bidi commands
% ------------------------------------------

\ifLuaTeX
    \providecommand{\setparLTR}{%
        \@RTLfalse
        \pardir TLT\relax
        \textdir TLT\relax
    }%

    \providecommand{\setparRTL}{%
        \@RTLtrue
        \pardir TRT\relax
        \textdir TRT\relax
    }%

    \providecommand{\beginR}{%
        \@RTLtrue
        \begingroup
        \textdir TRT\relax
    }%

    \providecommand{\beginL}{%
        \@RTLfalse
        \begingroup
        \textdir TLT\relax
    }%

    \def\endR{\endgroup}
    \def\endL{\endgroup}
\fi


% ------------------------------------------
% Core APIs
% ------------------------------------------

\providecommand{\RLE}[1]{%
    \leavevmode
    {%
        \bbl@textdir{1}%
        #1%
    }%
}%

\providecommand{\LRE}[1]{%
    \leavevmode
    {%
        \bbl@textdir{0}%
        #1%
    }%
}%

\ProvideDocumentEnvironment{RTL}{}
{%
    \par
    \begingroup
    \bbl@pardir{1}%
    \bbl@textdir{1}%
    \bbl@bodydir{1}
}
{%
    \par
    \endgroup
}%


\ProvideDocumentEnvironment{LTR}{}
{%
    \par
    \begingroup
    \bbl@pardir{0}%
    \bbl@textdir{0}%
    \bbl@bodydir{0}
}
{%
    \par
    \endgroup
}%

\let\LR\LRE
\let\RL\RLE


\makeatother

\endinput