% LoVullo rater specification params
%%

\NeedsTeXFormat{LaTeX2e}
\ProvidesClass{raterspec/param}
\ProcessOptions\relax


% special keywords for base param types
\def\@coreptype{core}
\def\@enumptype{enum}
\def\@unionptype{union}

\def\typedef{%
  \begingroup% ended by \@dotypedef
  \catcode`\_=11\relax
  \@dotypedef
}
\def\@dotypedef#1 #2: #3 \par{%
  \goodbreak%
  \index{parameter type!#2@\texttt{#2}|(}%
  \begingroup%
    % given foo<bar>, get foo and bar separately
    \edef\@root{\@ptype@root#1<||}%
    \edef\@type{\@ptype@type#1<#1>||}%
    \expandafter\gdef\csname ptype@#2\endcsname{#3}%
    % place definition into aux file; will be available next pass
    \protected@write\@auxout{}{%
      \string\expandafter\string\gdef
      \string\csname\space ptype@#2\string\endcsname{#3}%
    }%
    % typeset definition with link
    \item[%
      \hypertarget{@ptype:#2}{#2}%
      \ifx\@root\@coreptype\else%
        \ $\in\textrm{\rm\@type}$%
      \fi%
    ]\hfill\\%
    \@margin@sig%
    % ensure that the parent type actually exists
    \ifx\@root\@coreptype\else%
      \expandafter\ifx\csname ptype@\@type\endcsname\relax%
        \PackageTenativeError{raterspec}{%
          unknown parent param type `\@type' for `#2'}
      \fi%
    \fi%
    % process any keywords
    \ifx\@root\@enumptype
      \aftergroup\@typedef@enum
    \else\ifx\@root\@unionptype
      \aftergroup\@typedef@union
    \fi\fi
    \index{parameter type!#2@\texttt{#2}|)}%
    #3\par
  \endgroup
  \endgroup% from \typedef
}

% given a type foo<bar>, returns foo
\def\@ptype@root#1<#2||{#1}
% given a type foo<bar>, returns bar
\def\@ptype@type#1<#2>#3||{#2}

% strips the description and then puts all enums in an aligned environment
\def\@typedef@enum#1\enumv#2\par{%
  #1%
  \vskip0em\relax
  \begingroup
    \small
    % provide some extra give to prevent this from appearing on its own line
    \vspace{0em plus 0.5\parskip}%
    \goodbreak
    {\bf Defined values:}\\
    \vspace{-1.5\parskip}%
    \begin{longtable}{lc|l}
      % restore the enumv that we gobbled up
      \enumv#2
    \end{longtable}
  \endgroup
}
\def\enumv[#1]#2#3{%
  % define constant
  \expandafter\gdef\csname const@#2\endcsname{#1}%
  \expandafter\gdef\csname const@value@#2\endcsname{#3}%
  % place definition into aux file; will be available next pass
  \protected@write\@auxout{}{%
    \string\expandafter\string\gdef
    \string\csname\space const@#2\string\endcsname{#1}%
    \string\expandafter\string\gdef
    \string\csname\space constvalue@#2\string\endcsname{#3}%
  }%
  % typeset
  \index{constant!{\tt#2}}%
  {\tt\hypertarget{@const:#2}{#2}} & $#3$ & #1 \\
}

% strips the description and then puts all enums in an aligned environment
\def\@typedef@union#1\unionv#2\par{%
  #1%
  \vskip0em\relax
  \begingroup
    \small
    {\bf Any defined value of:}%
    \vspace{-\parskip}%
    \begin{itemize}
      \setlength{\itemsep}{-\parskip}%
      % restore the unionv that we gobbled up
      \unionv#2
    \end{itemize}
  \endgroup
}
\def\unionv#1{%
  % does this type exist?
  \expandafter\ifx\csname ptype@#1\endcsname\relax%
  \PackageTenativeError{raterspec}{unknown param type `#1' for union}
  \fi%
  \item{\typeref{#1}}
}

\def\typeref#1{%
  \index{parameter type!#1@\texttt{#1}}%
  \hyperlink{@ptype:#1}{\tt#1}%
}
\let\type\typeref

\def\constref #1{%
  \@ifnumeric{#1}%
    % numeric constants are simply output with no hyperlink
    $#1$%
  \else
    \index{constant!{\tt#1}}\hyperlink{@const:#1}{\tt#1}%
  \fi
}
\let\const\constref

% constant reference, show description
\def\constrefd#1{%
  \@ifnumeric{#1}%
    % numeric constants are simply output with no hyperlink
    $#1$%
  \else
    \index{constant!{\tt#1}}%
    \hyperlink{@const:#1}%
    {\csname const@#1\endcsname}%
  \fi
}
\def\constrefdd#1{\constrefd{#1}\dotfill}
% constant reference, show value
\def\constrefv#1{%
  \@ifnumeric{#1}%
    % numeric constants are simply output with no hyperlink
    $#1$%
  \else
    \index{constant!{\tt#1}}%
    \hyperlink{@const:#1}%
    {\csname const@value@#1\endcsname}%
  \fi
}
% link to constant with alternate text
\def\constrefalt#1#2{%
  \index{constant!{\tt#1}}%
  \hyperlink{@const:#1}{#2}%
}

\def\@type@exists@err#1{{%
  \expandafter\let\expandafter\@chk\csname ptype@#1\endcsname
  \ifx\@chk\relax
  \PackageTenativeError{raterspec}{parameter `#1' is undefined}%
  \fi
}}
\def\@const@exists@err#1{{%
  % ignore numeric constants (lazy check; anything that begins with a number)
  \@ifnumeric{#1}\else
    \expandafter\let\expandafter\@chk\csname const@#1\endcsname
    \ifx\@chk\relax
      \PackageTenativeError{raterspec}{constant `#1' is undefined}%
    \fi
  \fi
}}

\def\@const@desc#1{{%
  \@ifnumeric{#1}%
    % just output the text
    $#1$%
  \else
    % output desc
    \csname const@#1\endcsname
  \fi
}}


% denotes a param that will likely be calculated
\def\metaparamdef{\paramdef}


% param definition
% note that the description is included in this input as well; this allows us to
% use this information for code generation/etc
\def\paramdef{%
  \begingroup
  \catcode`_=11\relax
  \@doparamdef
}
\def\@doparamdef#1 #2: #3 \par{%
  \goodbreak%
  \index{parameter!#2@\texttt{#2}|(}%
  \begingroup%
    \def\@given{#1}%
    % given foo<bar>, get foo and bar separately
    \edef\@root{\@ptype@root#1<||}%
    \edef\@type{\@ptype@type#1<#1>||}%
    \expandafter\gdef\csname param@#2\endcsname{#3}%
    % place definition into aux file; will be available next pass
    \protected@write\@auxout{}{%
      \string\expandafter\string\gdef
      \string\csname\space param@#2\string\endcsname{#3}%
    }%
    % does the given type exist (note that this check assumes that the typedef
    % appears before the param in the specs, as is currently the case)
    \expandafter\ifx\csname ptype@\@type\endcsname\relax%
      \PackageTenativeError{raterspec}{unknown param type: \@type}
    \fi%
    % typeset definition with link
    \item[%
      \hypertarget{@param:#2}{{\tt#2}}%
      \ $\in\textrm{%
        \rm\typeref{\@type}%
        % output root only if provided (if not, then because of how \@type
        % called \@ptype@type, it will be equal to #1)
        \ifx\@root\@given\else%
          \ $\langle$\@root$\rangle$
        \fi
      }$%
    ]\hfill\\%
    \@margin@sig%
    % remove mysterious space from margin sig
    \hskip-1ex\relax%
    #3%
    \ifx\@root\@given
      \@codegen{<lv:param name="#2" type="\@type" desc="#3"/>}%
    \else
      \@codegen{<lv:param name="#2" type="\@type" set="\@root"%
        \space desc="#3"/>%
      }%
    \fi
  \endgroup%
  \index{parameter!#2@\texttt{#2}|)}%
  \endgroup
}

\def\paramref{%
  \begingroup% ended by \@dotypedef
  \catcode`\_=11\relax
  \@doparamref
}
\def\@doparamref#1{%
  % prevent scantokens from adding a space at the end
  \endlinechar-1\relax
  \expandafter\let\expandafter\@@chk\csname param@#1\endcsname
  \ifx\@@chk\relax
    \PackageTenativeError{raterspec}{unknown param: #1}
  \fi
  \index{parameter!#1@\texttt{#1}}%
  \hyperlink{@param:#1}%
    {\tt\scantokens{#1}}%
  \endgroup
}
\let\param\paramref

\def\paramrefd#1{%
  \expandafter\let\expandafter\@@pchk\csname param@#1\endcsname
  \ifx\@@pchk\empty
    \PackageTenativeError{raterspec}{Unknown parameter: #1}%
  \else
    % output
    \@@pchk
  \fi
}

\def\locparam#1{%
  \ifmmode
    \mathop{\paramref{#1}_\loc}
  \else
    $\locparam{#1}$%
  \fi
}