% \iffalse meta-comment -------------------------------------------------------
% Copyright 2015 Matthias Vogelgesang and the LaTeX community. A full list of
% contributors can be found at
%
%     https://github.com/matze/mtheme/graphs/contributors
%
% and the original template was based on the HSRM theme by Benjamin Weiss.
%
% This work is licensed under a Creative Commons Attribution-ShareAlike 4.0
% International License (https://creativecommons.org/licenses/by-sa/4.0/).
% ------------------------------------------------------------------------- \fi
% \iffalse
%<driver> \ProvidesFile{beamerouterthememetropolis.dtx}
%<*package>
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{beamerouterthememetropolis}
    [2015/06/12 A Modern Beamer Theme]
%</package>
%<driver> \documentclass{ltxdoc}
%<driver> \usepackage{beamerouterthememetropolis}
%<driver> \begin{document}
%<driver> \DocInput{beamerouterthememetropolis.dtx}
%<driver> \end{document}
% \fi
% \CheckSum{0}
% \StopEventually{}
% \iffalse
%<*package>
% ------------------------------------------------------------------------- \fi
%
% \subsection{\textsc{metropolis} outer theme}
%
% A |beamer| outer theme dictates the style of the frame elements traditionally
% set outside the body of each slide: the head, footline, and frame title.
%
% Load required packages.
%    \begin{macrocode}
\RequirePackage{etoolbox}
\RequirePackage{calc}
\RequirePackage{pgfopts}
%    \end{macrocode}
%
%
%
% \subsubsection{Options}
%
% \begin{macro}{numbering}
% This option controls the page numbering.
%    \begin{macrocode}
\pgfkeys{
  /metropolis/outer/numbering/.cd,
    .is choice,
    none/.code=\setbeamertemplate{frame numbering}[none],
    counter/.code=\setbeamertemplate{frame numbering}[counter],
    fraction/.code=\setbeamertemplate{frame numbering}[fraction],
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{progressbar}
% This option controls the progressbar.
%    \begin{macrocode}
\pgfkeys{
  /metropolis/outer/progressbar/.cd,
    .is choice,
    none/.code=\setbeamertemplate{frametitle}[plain],
    frametitle/.code=\setbeamertemplate{frametitle}[progressbar],
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{frametitleformat}
% Control the case style of the frame title
%    \begin{macrocode}
\pgfkeys{
  /metropolis/outer/frametitleformat/.cd,
    .is choice,
    regular/.code=\renewcommand{\@metropolis@frametitleformat}{},
    lowercase/.code={%
      \renewcommand{\@metropolis@frametitleformat}{\MakeLowercase}
    },
    uppercase/.code={%
      \renewcommand{\@metropolis@frametitleformat}{\MakeUppercase}
    },
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@metropolis@outer@setdefaults}
% Set default values for outer theme options.
%    \begin{macrocode}
\newcommand{\@metropolis@outer@setdefaults}{
  \pgfkeys{/metropolis/outer/.cd,
    numbering=counter,
    progressbar=none,
    frametitleformat=lowercase,
  }
}
%    \end{macrocode}%
% \end{macro}
%
%
%
% \subsubsection{Head and footline}
%
% All good |beamer| presentations should already remove the navigation symbols,
% but \textsc{metropolis} removes them automatically (just in case).
%
%    \begin{macrocode}
\setbeamertemplate{navigation symbols}{}
%    \end{macrocode}
%
% Template for the frame number. Can be omitted, shown or displayed as a
% fraction of the total frames.
%
%    \begin{macrocode}
\defbeamertemplate{frame numbering}{none}{
  % intentionally empty
}
\defbeamertemplate{frame numbering}{counter}{
  \insertframenumber
}
\defbeamertemplate{frame numbering}{fraction}{
  \insertframenumber/\inserttotalframenumber
}
%    \end{macrocode}
%
% The only element in the footline by default is the frame number.
%
%    \begin{macrocode}
\setbeamertemplate{footline}{%
  \begin{beamercolorbox}[%
      wd=\textwidth,
      ht=3ex,
      dp=3ex,
      leftskip=0.3cm,
      rightskip=0.3cm
    ]{footline}%
  \hfill\usebeamerfont{page number in head/foot}%
  \usebeamertemplate*{frame numbering}
  \end{beamercolorbox}%
}
%    \end{macrocode}
%
%
%
% \subsubsection{Frametitle}
%
% \begin{macro}{\@metropolis@frametitleformat}
%   Define a hook to change the case format of the frame title.
%    \begin{macrocode}
\def\@metropolis@frametitleformat#1{#1}
%    \end{macrocode}
% \end{macro}
%
% To make the |\MakeLowercase| and |\MakeUppercase| macros work in the
% frame title we have to patch |\beamer@@frametitle|. This solution was
% suggested by Enrico Gregorio in an answer to
% \href{http://tex.stackexchange.com/questions/112526/}{this StackExchange
% question}.
%
%    \begin{macrocode}
\patchcmd{\beamer@@frametitle}
  {\beamer@ifempty{#2}{}{%
      \gdef\insertframetitle{{#2\ifnum\beamer@autobreakcount>0\relax{}\space\usebeamertemplate*{frametitle continuation}\fi}}%
    \gdef\beamer@frametitle{#2}%
    \gdef\beamer@shortframetitle{#1}%
    }}
  {\beamer@ifempty{#2}{}{%
      \gdef\insertframetitle{{\@metropolis@frametitleformat{#2}\ifnum\beamer@autobreakcount>0\relax{}\space\usebeamertemplate*{frametitle continuation}\fi}}%
    \gdef\beamer@frametitle{#2}%
    \gdef\beamer@shortframetitle{#1}%
    }}
  {}
  {\PackageError{beamerouterthememetropolis}{Patching frame title failed.}}
%    \end{macrocode}
%
% \begin{macro}{frametitle}
%
% Templates for the frame title, which is optionally underlined with a
% progress bar.
%
%    \begin{macrocode}
\defbeamertemplate{frametitle}{plain}{%
  \nointerlineskip
  \begin{beamercolorbox}[%
      wd=\paperwidth,
      leftskip=0.3cm,
      rightskip=0.3cm,
      ht=2.5ex,
      dp=1.5ex
    ]{frametitle}
  \insertframetitle%
  \end{beamercolorbox}%
}
\defbeamertemplate{frametitle}{progressbar}{%
  \nointerlineskip
  \begin{beamercolorbox}[%
      wd=\paperwidth,
      leftskip=0.3cm,
      rightskip=0.3cm,
      ht=2.5ex,
      dp=1.5ex
    ]{frametitle}
  \insertframetitle%
  \end{beamercolorbox}%
  \usebeamertemplate*{progress bar in head/foot}
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{progress bar in head/foot}
%
% Template for the progress bar optionally displayed below the frame title
% on each page. Much of this code is duplicated in the inner theme's template
% |progress bar in section page|.
%
%    \begin{macrocode}
\newlength{\metropolis@progressinheadfoot}
\setbeamertemplate{progress bar in head/foot}{
  \nointerlineskip
  \setlength{\metropolis@progressinheadfoot}{%
    \paperwidth * \ratio{\insertframenumber pt}{\inserttotalframenumber pt}%
  }%
  \begin{beamercolorbox}[
      wd=\paperwidth,
      ht=0.4pt,
      dp=0pt]{progress bar in head/foot}
    \begin{tikzpicture}
      \draw[bg, fill=bg] (0,0) rectangle (\paperwidth, 0.4pt);
      \draw[fg, fill=fg] (0,0) rectangle (\metropolis@progressinheadfoot, 0.4pt);
    \end{tikzpicture}%
  \end{beamercolorbox}
}
%    \end{macrocode}
% \end{macro}
%
% Process package options
%
%    \begin{macrocode}
\@metropolis@outer@setdefaults
\ProcessPgfPackageOptions{/metropolis/outer}
%    \end{macrocode}
%
% \iffalse
%</package>
% \fi
% \Finale
\endinput