% Copyright 2003--2007 by Till Tantau
% Copyright 2010 by Vedran Mileti\'c
% Copyright 2010,2012--2015 by Vedran Mileti\'c, Joseph Wright
% Copyright 2017 by Joseph Wright
%
% This file may be distributed and/or modified
%
% 1. under the LaTeX Project Public License and/or
% 2. under the GNU Public License.
%
% See the file doc/licenses/LICENSE for more details.

\mode
<all>

\RequirePackage{enumerate}

\mode
<presentation>

%
%
% The \frametitle command
%
%
\newcommand<>\frametitle{\alt#1{\@dblarg\beamer@@frametitle}{\beamer@gobbleoptional}}
\long\def\beamer@@frametitle[#1]#2{%
  \ifblank{#2}{}{%
    \gdef\insertframetitle{{#2\ifnum\beamer@autobreakcount>0\relax{}\space\usebeamertemplate*{frametitle continuation}\fi}}%
  \gdef\beamer@frametitle{#2}%
  \gdef\beamer@shortframetitle{#1}%
}%
}

\newcommand\insertshortframetitle[1][]{%
  {%
    \beamer@setupshort{#1}%
    \beamer@insertshort{\beamer@shortframetitle}%
  }}


\mode
<all>
{
  \let\beamer@aftersubtitle=\relax
  \newcommand<>\framesubtitle[1]{\only#2{\ifblank{#1}{}{\gdef\insertframesubtitle{{#1}}\beamer@aftersubtitle}}}
}


\mode
<article>
{
  \newcommand<>\frametitle[2][]{\only#3{\gdef\insertframetitle{#2}%
      \@ifnextchar\framesubtitle{\beamer@donextsubtitle}{\usebeamertemplate{frametitle}}}}
   \renewcommand<>\framesubtitle[1]{%
     \only#2{%
       \ifblank{#1}
         {\usebeamertemplate{frametitle}}
         {\gdef\insertframesubtitle{{#1}}\beamer@aftersubtitle}}}
  \def\beamer@donextsubtitle{%
    % Ugly hack...
    \def\beamer@aftersubtitle{\usebeamertemplate{frametitle}\let\beamer@aftersubtitle=\relax}
    }
}



%
% Alerting
%

\mode
<all>
{
  \newenvironment<>{alertenv}{\begin{altenv}#1%
      {\usebeamercolor[fg]{alerted text}\usebeamerfont{alerted text}\usebeamertemplate{alerted text begin}}
      {\usebeamertemplate{alerted text end}}{\color{.}}{}\ignorespaces}{\ifhmode\unskip\fi\end{altenv}}

  \newenvironment<>{structureenv}{\begin{altenv}#1%
      {\usebeamercolor[fg]{structure}\usebeamerfont{structure}\usebeamertemplate{structure text begin}}
      {\usebeamertemplate{structure text end}}{\color{.}}{}\ignorespaces}{\ifhmode\unskip\fi\end{altenv}}

  \newcommand<>{\alert}[1]{\begin{alertenv}#2\relax#1\end{alertenv}}
  \newcommand<>{\structure}[1]{\begin{structureenv}#2\relax#1\end{structureenv}}
}



%
%
% Predefined Blocks
%
%

\mode
<all>
{
  \newenvironment<>{block}[1]{%
    \begin{actionenv}#2%
      \def\insertblocktitle{#1}%
      \par%
      \usebeamertemplate{block begin}}
    {\par%
      \usebeamertemplate{block end}%
    \end{actionenv}}

  \newenvironment<>{alertblock}[1]{%
    \begin{actionenv}#2%
      \def\insertblocktitle{#1}%
      \par%
      \mode<presentation>{%\usebeamerfont{block}%
        \setbeamercolor{local structure}{parent=alerted text}}%
      \usebeamertemplate{block alerted begin}}
    {\par%
      \usebeamertemplate{block alerted end}%
    \end{actionenv}}

  \newenvironment<>{exampleblock}[1]{%
    \begin{actionenv}#2%
      \def\insertblocktitle{#1}%
      \par%
      \mode<presentation>{%\usebeamerfont{block}%
        \setbeamercolor{local structure}{parent=example text}}%
      \usebeamertemplate{block example begin}}
    {\par%
      \usebeamertemplate{block example end}%
    \end{actionenv}}
}


%
% List stuff
%

\setlength\leftmargini  {2em}
\setlength\leftmarginii  {2em}
\setlength\leftmarginiii  {2em}
\setlength  \labelsep  {.5em}
\setlength  \labelwidth{\leftmargini}
\addtolength\labelwidth{-\labelsep}

\def\@listi{\leftmargin\leftmargini
            \topsep 3\p@ \@plus2\p@ \@minus2.5\p@
            \parsep 0\p@
            \itemsep3\p@ \@plus2\p@ \@minus3\p@}
\let\@listI\@listi
\def\@listii{\leftmargin\leftmarginii
              \topsep    2\p@ \@plus1\p@ \@minus2\p@
              \parsep    0\p@   \@plus\p@
              \itemsep   \parsep}
\def\@listiii{\leftmargin\leftmarginiii
              \topsep    2\p@ \@plus1\p@ \@minus2\p@
              \parsep    0\p@   \@plus\p@
              \itemsep   \parsep}


%
%
% Enumerations
%
%

\def\enumerate{%
  \ifnum\@enumdepth>2\relax\@toodeep
  \else%
    \advance\@enumdepth\@ne%
    \edef\@enumctr{enum\romannumeral\the\@enumdepth}%
    \advance\@itemdepth\@ne%
  \fi%
  \beamer@computepref\@enumdepth% sets \beameritemnestingprefix
  \edef\beamer@enumtempl{enumerate \beameritemnestingprefix item}%
  \@ifnextchar[{\beamer@@enum@}{\beamer@enum@}}
\def\beamer@@enum@[{\@ifnextchar<{\beamer@enumdefault[}{\beamer@@@enum@[}}
\def\beamer@enumdefault[#1]{\def\beamer@defaultospec{#1}%
  \@ifnextchar[{\beamer@@@enum@}{\beamer@enum@}}
\def\beamer@@@enum@[#1]{% partly copied from enumerate.sty
  \@enLab{}\let\@enThe\@enQmark
  \@enloop#1\@enum@
  \ifx\@enThe\@enQmark\@warning{The counter will not be printed.%
    ^^J\space\@spaces\@spaces\@spaces The label is: \the\@enLab}\fi
  \def\insertenumlabel{\the\@enLab}
  \def\beamer@enumtempl{enumerate mini template}%
  \expandafter\let\csname the\@enumctr\endcsname\@enThe
  \csname c@\@enumctr\endcsname7
  \expandafter\settowidth
            \csname leftmargin\romannumeral\@enumdepth\endcsname
            {\the\@enLab\hspace{\labelsep}}%
  \beamer@enum@}
\def\beamer@enum@{%
  \beamer@computepref\@itemdepth% sets \beameritemnestingprefix
  \usebeamerfont{itemize/enumerate \beameritemnestingprefix body}%
  \usebeamercolor[fg]{itemize/enumerate \beameritemnestingprefix body}%
  \usebeamertemplate{itemize/enumerate \beameritemnestingprefix body begin}%
  \expandafter
    \list
      {\usebeamertemplate{\beamer@enumtempl}}
      {\usecounter\@enumctr%
        \def\makelabel##1{{\hss\llap{{%
                \usebeamerfont*{enumerate \beameritemnestingprefix item}%
                \usebeamercolor[fg]{enumerate \beameritemnestingprefix item}##1}}}}}%
  \beamer@cramped%
  \raggedright%
  \beamer@firstlineitemizeunskip%
}
\def\endenumerate{\ifhmode\unskip\fi\endlist%
   \usebeamertemplate{itemize/enumerate \beameritemnestingprefix body end}}

\def\beamer@computepref#1{%
  \let\beameritemnestingprefix\@empty%
  \ifcase#1\or\or\def\beameritemnestingprefix{sub}\or\def\beameritemnestingprefix{subsub}\or\@toodeep\fi%
}

\def\insertenumlabel{\theenumi}
\def\insertsubenumlabel{\theenumii}
\def\insertsubsubenumlabel{\theenumiii}

\mode
<article>
{
  \AtBeginDocument{ % Remove any overlay specification
    \let\beamer@@@enum@\@@enum@
    \def\@@enum@[{%
      \@ifnextchar<%
        {\beamer@@@num@@}
        {\beamer@@@enum@[}%
    }
    \def\beamer@@@num@@<#1>]{%
      \@ifnextchar[%
        {\beamer@@@enum@}
        {\@enum@}%
    }
    %\let\beamer@origenumerate=\enumerate
    %\renewcommand*\enumerate{\beamer@origenumerate}
  }
}



%
%
% Itemize
%
%

\renewcommand{\itemize}[1][]{%
  \ifblank{#1}{}{\def\beamer@defaultospec{#1}}%
  \ifnum \@itemdepth >2\relax\@toodeep\else
    \advance\@itemdepth\@ne
    \beamer@computepref\@itemdepth% sets \beameritemnestingprefix
    \usebeamerfont{itemize/enumerate \beameritemnestingprefix body}%
    \usebeamercolor[fg]{itemize/enumerate \beameritemnestingprefix body}%
    \usebeamertemplate{itemize/enumerate \beameritemnestingprefix body begin}%
    \list
      {\usebeamertemplate{itemize \beameritemnestingprefix item}}
      {\def\makelabel##1{%
          {%
            \hss\llap{{%
                \usebeamerfont*{itemize \beameritemnestingprefix item}%
                \usebeamercolor[fg]{itemize \beameritemnestingprefix item}##1}}%
          }%
        }%
      }
  \fi%
  \beamer@cramped%
  \raggedright%
  \beamer@firstlineitemizeunskip%
}

\def\enditemize{\ifhmode\unskip\fi\endlist%
  \usebeamertemplate{itemize/enumerate \beameritemnestingprefix body end}}

\let\beamer@itemize\itemize

\mode
<article>
{
  \AtBeginDocument{
    \let\beamer@origitemize=\itemize
    \def\itemize{%
      \@ifnextchar[{\beamer@itemize@}{\beamer@origitemize}%
    }
    \def\beamer@itemize@[{%
      \@ifnextchar<{\beamer@itemize@@}{\beamer@origitemize[}%
    }
    \def\beamer@itemize@@<#1>]{\beamer@origitemize}
  }
}




\def\description{\@ifnextchar[{\beamer@testforospec}{\beamer@descdefault\beamer@descriptionwidth\@@description}}
\def\beamer@testforospec[{\@ifnextchar<{\beamer@scandefaultospec[}{\@description[}}
\def\beamer@scandefaultospec[#1]{\def\beamer@defaultospec{#1}\description}
\def\@description[#1]{\setbox\beamer@tempbox=\hbox{\def\insertdescriptionitem{#1}\usebeamertemplate**{description item}}%
  \beamer@descdefault\wd\beamer@tempbox\@@description}
\def\@@description{%
  \advance\beamer@descdefault by \labelsep%
  \usebeamerfont{description body}%
  \usebeamercolor[fg]{description body}%
  \usebeamertemplate{description body begin}%
  \list
  {}
  {\labelwidth\beamer@descdefault\leftmargin\beamer@descdefault\let\makelabel\beamer@descriptionitem}%
  \beamer@cramped%
  \raggedright
  \beamer@firstlineitemizeunskip%
}
\def\enddescription{\ifhmode\unskip\fi\endlist%
  \usebeamertemplate{description body end}}
\long\def\beamer@descriptionitem#1{%
  \def\insertdescriptionitem{#1}%
  \hfil\hspace\labelsep{\usebeamertemplate**{description item}}}

\beamer@descriptionwidth=2cm
\define@key{beamer@margin}{description width}{%
  \beamer@descriptionwidth=#1\relax%
}
\define@key{beamer@margin}{description width of}{%
  \setbox\beamer@tempbox=\hbox{\def\insertdescriptionitem{#1}\usebeamertemplate**{description item}}%
  \beamer@descriptionwidth=\wd\beamer@tempbox\relax%
}

\mode
<article>
{
  \AtBeginDocument{
    \let\beamer@origdescription=\description
    % The description environment doesn't use either optional
    % arg in article mode, so simply gobble them
    \def\description{%
      \@ifnextchar[%]
        {\beamer@description@}
        {\beamer@origdescription}%
    }
    \def\beamer@description@[#1]{%
      \@ifnextchar[%]
        {\beamer@description@@}
        {\beamer@origdescription}%
    }
    \def\beamer@description@@[#1]{\beamer@origdescription}
  }
}






%
% Abstract command
%

\newenvironment<>{abstract}%
{\actionenv#1%
  \usebeamertemplate{abstract begin}%
  \usebeamerfont{abstract}%
  \usebeamercolor{abstract}%
  \usebeamertemplate**{abstract title}}%
{\usebeamertemplate{abstract end}\endactionenv}


%
% Verse, quotation, quote environments
%

\newenvironment<>{verse}
{\actionenv#1%
  \usebeamertemplate{verse begin}%
  \usebeamerfont{verse}%
  \usebeamercolor{verse}%
  \let\\\@centercr%
  \list{}{\itemsep      \z@
    \itemindent   -1.5em%
    \listparindent\itemindent
    \rightmargin  \leftmargin
    \advance\leftmargin 1.5em
    \parsep       .75em plus .25em minus.25em}%
\item\relax}
{\endlist\usebeamertemplate{verse end}\endactionenv}


\newenvironment<>{quotation}
{\actionenv#1%
  \usebeamertemplate{quotation begin}
  \usebeamerfont{quotation}%
  \usebeamercolor{quotation}%
  \list{}{\listparindent 1.5em%
    \itemindent    \listparindent
    \rightmargin   \leftmargin
    \parsep        \z@ \@plus\p@}%
\item\relax}
{\endlist\usebeamertemplate{quotation end}\endactionenv}

\newenvironment<>{quote}
{\actionenv#1%
  \usebeamertemplate{quote begin}%
  \usebeamerfont{quote}%
  \usebeamercolor{quote}%
  \list{}{\rightmargin   \leftmargin}
\item\relax}
{\endlist\usebeamertemplate{quote end}\endactionenv}


\mode
<article>
{
  \renewenvironment<>{verse}{\actionenv#1\originalverse}{\endoriginalverse\endactionenv}
  \renewenvironment<>{quotation}{\actionenv#1\originalquotation}{\endoriginalquotation\endactionenv}
  \renewenvironment<>{quote}{\actionenv#1\originalquote}{\endoriginalquote\endactionenv}
}




%
% Bibliography code
%
\newenvironment{thebibliography}[1]
{%\leavevmode\unskip%
  \list{\@biblabel{\@arabic\c@enumiv}}%
           {\settowidth\labelwidth{\beamer@biblabeltemplate{\@biblabel{#1}}}%
            \leftmargin\labelwidth
            \advance\leftmargin\labelsep
            \itemsep=0pt%
            \partopsep=0pt%
            \topsep=0pt%
            \usecounter{enumiv}%
            \let\p@enumiv\@empty
            \renewcommand\theenumiv{\@arabic\c@enumiv}
            \let\makelabel\beamer@biblabeltemplate}%
      \sloppy\raggedright
      \clubpenalty10000
      \@clubpenalty \clubpenalty
      \widowpenalty10000%
      \sfcode`\.\@m}
     {\def\@noitemerr
       {\@latex@warning{Empty `thebibliography' environment}}%
      \ifhmode\unskip\fi\endlist}

\long\def\beamer@biblabeltemplate#1{\def\insertbiblabel{#1}\usebeamertemplate*{bibliography item}\hfil}

\def\bibitem{\@ifnextchar<{\beamer@bibitem@store}{\gdef\beamer@bibstore{}\beamer@plainbibitem}}
\def\beamer@bibitem@store<#1>{\gdef\beamer@bibstore{<#1>}\beamer@plainbibitem}
\def\beamer@plainbibitem{\@ifnextchar[\@lbibitem\beamer@bibitem}
\def\@lbibitem[#1]#2{\expandafter\item\beamer@bibstore[\@biblabel{#1}\hfill]%
  \@ifundefined{beamerbib@#2@\the\c@framenumber}{\if@filesw
    {\let\protect\noexpand
      \immediate
      \write\@auxout{\string\bibcite{#2}{\noexpand\hyperlink{beamerbib#2}{#1}}}}\fi%
    \global\@namedef{beamerbib@#2@\the\c@framenumber}{\relax}%
    \hypertarget{beamerbib#2}{}%
    }{}%
  \def\newblock{\beamer@newblock}\newblock%
  \hbox{}\ignorespaces}
\def\beamer@bibitem#1{\@bibitem{#1}\ignorespaces}
\def\@bibitem#1{\expandafter\item\beamer@bibstore\@ifundefined{beamerbib@#1@\the\c@framenumber}%
  {\if@filesw \immediate\write\@auxout
    {\string\bibcite{#1}{\noexpand\hyperlink{beamerbib#1}{\the\value{\@listctr}}}}\fi%
    \global\@namedef{beamerbib@#1@\the\c@framenumber}{\relax}%
    \hypertarget{beamerbib#1}{}}%
  {}%
  \def\newblock{\beamer@newblock}\newblock}
\def\newblock{\beamer@newblock}

\def\beamer@newblock{%
  \usebeamercolor[fg]{bibliography entry author}%
  \usebeamerfont{bibliography entry author}%
  \usebeamertemplate{bibliography entry author}%
  \def\newblock{%
    \usebeamercolor[fg]{bibliography entry title}%
    \usebeamerfont{bibliography entry title}%
    \usebeamertemplate{bibliography entry title}%
    \def\newblock{%
      \usebeamercolor[fg]{bibliography entry location}%
      \usebeamerfont{bibliography entry location}%
      \usebeamertemplate{bibliography entry location}%
      \def\newblock{%
        \usebeamercolor[fg]{bibliography entry note}%
        \usebeamerfont{bibliography entry note}%
        \usebeamertemplate{bibliography entry note}}}}%
  \leavevmode\setbox\beamer@tempbox=\hbox{}\ht\beamer@tempbox=1.5em\box\beamer@tempbox}

% The following code provided by Audrey http://tex.stackexchange.com/a/57247
\AtBeginDocument{%
  \@ifpackageloaded{biblatex}
    {\apptocmd{\blx@env@bibliography}
       {\let\makelabel\beamer@biblabeltemplate}{}{}
     \apptocmd{\abx@macro@begentry}
       {\let\bbx@tempa\@empty%
        \usebeamercolor[fg]{bibliography entry author}}{}{}
     \pretocmd{\abx@macro@labeltitle}
       {\ifboolexpr{ test {\ifcsundef{abx@field@label}}
          and test {\ifcsundef{abx@field@labeltitle}} }{}{\let\bbx@tempa\labelnamepunct}}{}{}
     \pretocmd{\abx@macro@title}
       {\ifcsundef{abx@name@labelname}{}{\let\bbx@tempa\labelnamepunct}%
        \bbx@tempa\newblock\unspace\usebeamercolor[fg]{bibliography entry title}}{}{}
     \apptocmd{\abx@macro@title}
       {\ifcsundef{abx@field@title}{}{\ifpunct{}{\midsentence\newunitpunct}}%
        \newblock\unspace\usebeamercolor[fg]{bibliography entry note}}{}{}}
    {}}

\mode
<article>
{
  \AtBeginDocument{
    \renewcommand<>{\bibitem}{\beameroriginal{\bibitem}}%should actually suppress
  }
}



%
% Floats and tables
%

\newenvironment{figure}[1][]{%
  \def\@captype{figure}%
  \par\nobreak\begin{center}\nobreak}
  {\par\nobreak\end{center}}
\newcounter{figure}
\renewcommand\thefigure{\@arabic\c@figure}

\newenvironment{table}[1][]{%
  \def\@captype{table}%
  \par\nobreak\begin{center}\nobreak}
  {\par\nobreak\end{center}\nobreak}
\newcounter{table}
\renewcommand\thetable{\@arabic\c@table}

\newlength\abovecaptionskip
\newlength\belowcaptionskip
\setlength\abovecaptionskip{7pt}
\setlength\belowcaptionskip{7pt}

\def\caption{%
  \ifx\@captype\@undefined
    \@latex@error{\noexpand\caption outside figure or table}\@ehd
    \expandafter\@gobble
 \else
   \refstepcounter\@captype
   \expandafter\@firstofone
 \fi
 {\@dblarg{\@caption\@captype}}%
}
\long\def\@caption#1[#2]#3{% second argument ignored
  \par\nobreak
  \begingroup
    \@parboxrestore
    \if@minipage
      \@setminipage
    \fi
    \beamer@makecaption{#1}{\ignorespaces #3}\par\nobreak
    \endgroup}
\long\def\beamer@makecaption#1#2{%
  \def\insertcaptionname{\csname#1name\endcsname}%
  \def\insertcaptionnumber{\csname the#1\endcsname}%
  \def\insertcaption{#2}%
  \nobreak\vskip\abovecaptionskip\nobreak
  \sbox\@tempboxa{\usebeamertemplate**{caption}}%
  \ifdim \wd\@tempboxa >\hsize
    \usebeamertemplate**{caption}\par
  \else
    \global \@minipagefalse
    \hb@xt@\hsize{\hfil\box\@tempboxa\hfil}%
  \fi
  \nobreak\vskip\belowcaptionskip\nobreak}


\mode
<all>