__HEADER__(Replacement package)
\RequirePackage{xkeyval}
\RequirePackage{todonotes}
\RequirePackage{xparse}
\RequirePackage{etoolbox}

__NEW_IF__(english, true)
\DeclareOptionX{english}{__SET_IF__(english,true)}
\DeclareOptionX{german}{__SET_IF__(english,false)}
\DeclareOptionX{ngerman}{__SET_IF__(english,false)}

\define@boolkey+{__FILE_NAME__}[__PACKAGE_PREFIX__]{strict}[true]{
    \if__PACKAGE_PREFIX__strict
        __INFO__(Strict mode enabled. Undefined restates will throw errors.)%
    \else
        __INFO__(Strict mode disabled. Undefined restates will now print placeholder boxes)%
    \fi
}{
        __WARNING__({Erroneous input to key 'strict' ignored. Provide =true or =false.)
}
\ProcessOptionsX*\relax

\newcommand\restatesetup[1]{\setkeys{__FILE_NAME__}{#1}}


\NewDocumentCommand{\restatetheorem}{s m}{
    \ifcsdef{#2}{
        \ifx#1\BooleanTrue\csname#2\endcsname*\else\csname#2\endcsname\fi
    }{
    __IF__(strict)
    \PackageError{__PACKAGE_NAME__}{Strict mode enabled but restate command not defined}{The theorem you tried to restate is not defined. Either make sure it is so that it can be printed or disable the strict mode with \noexpand\restatesetup{strict=false} to print a placeholder instead}
    \else
    \missingfigure{__IF__(english) Here theorem \textbf{#2} is missing, since it is not part of this document.\else Hier fehlt die Wiederholung von Satz \textbf{#2}, der nicht Teil dieses Dokumentes ist.\fi}
    \fi
    }
}