% ..............................................................................
% The inner beamer theme accoridng to the FAU corporate style guide 2021, see 
%
% https://www.intern.fau.de/kommunikation-marketing-und-corporate-identity/corporate-identity/
%
%
% Copyright 2022 by Tim Roith <tim.roith@fau.de>
%
% This program can be redistributed and/or modified under the terms
% of the GNU Public License, version 2.
%
% ------------------------------------------------------------------------------

\ProvidesPackage{styles/beamerinnerthemefau}
\RequirePackage{fp}

\newdimen\fau@inner@WordMarkTitleHeight
\newdimen\fau@inner@WordMarkTitleWidth
\newdimen\fau@inner@TitleTitleSkip
\newdimen\fau@inner@HeaderHeight
\newdimen\fau@inner@TitleHeight
\newdimen\fau@inner@TitleLineHeight
\newdimen\fau@inner@RightMargin

% ------------------------------------------------------------------------------
% Dimensions
\def\fau@inner@XScale{1.}
\def\fau@inner@YScale{1.}
\DeclareOptionBeamer{XScale}{\def\fau@inner@XScale{#1}} % scale factor for x dimension
\DeclareOptionBeamer{YScale}{\def\fau@inner@YScale{#1}} % scale factor for y dimension


\DeclareOptionBeamer{WordMarkTitleHeight}{\fau@inner@WordMarkTitleHeight=#1}
\DeclareOptionBeamer{WordMarkTitleWidth}{\fau@inner@WordMarkTitleWidth=#1}
\DeclareOptionBeamer{TitleTitleSkip}{\fau@inner@TitleTitleSkip=#1}
\DeclareOptionBeamer{HeaderHeight}{\fau@inner@HeaderHeight=#1}
\DeclareOptionBeamer{TitleHeight}{\fau@inner@TitleHeight=#1}
\DeclareOptionBeamer{TitleLineHeight}{\fau@inner@TitleLineHeight=#1}
\DeclareOptionBeamer{RightMargin}{\fau@inner@RightMargin=#1}

\DeclareOptionBeamer{WordMarkTitle}{\def\fau@inner@WordMarkTitle{#1}}
\DeclareOptionBeamer{TitleArt}{\def\fau@inner@TitleArt{#1}}

% ..............................................................................
\ProcessOptionsBeamer
\RequirePackage{tikz}
\RequirePackage{graphicx}
\mode<presentation>
% ------------------------------------------------------------------------------
% Scale the dimensions
\fau@inner@WordMarkTitleHeight=\fau@inner@YScale\dimexpr\fau@inner@WordMarkTitleHeight
\fau@inner@WordMarkTitleWidth=\fau@inner@XScale\dimexpr\fau@inner@WordMarkTitleWidth
\fau@inner@TitleTitleSkip=\fau@inner@YScale\dimexpr\fau@inner@TitleTitleSkip
\fau@inner@HeaderHeight=\fau@inner@YScale\dimexpr\fau@inner@HeaderHeight
\fau@inner@TitleHeight=\fau@inner@YScale\dimexpr\fau@inner@TitleHeight
\fau@inner@TitleLineHeight=\fau@inner@YScale\dimexpr\fau@inner@TitleLineHeight
\fau@inner@RightMargin=\fau@inner@YScale\dimexpr\fau@inner@RightMargin

% ..............................................................................
% Title page
% ------------------------------------------------------------------------------
\define@key{beamerframe}{titleimage}[true]{%
  \setbeamertemplate{background}{
  	\vbox to \paperheight{%
  	\vfill%
    \includegraphics[%
    	width=\paperwidth,%
    	height=\dimexpr\paperheight-%
    		   \fau@inner@HeaderHeight-%
    		   \fau@inner@TitleHeight-%
    		   \fau@inner@TitleLineHeight]{\fau@inner@TitleArt}%
    }%
  }%
  \setbeamertemplate{headline}[headline title]
  %\setbeamertemplate{sidebar left}[sidebar title theme]
  \setbeamertemplate{sidebar left}{}
  \setbeamertemplate{frametitle}[frametitle title]
  \setbeamertemplate{footline}[footline off]
  \setbeamercolor{background canvas}{bg=BaseColor}%
  \setbeamercolor{section in toc}{fg=TitleFont}%
  \setbeamercolor{subsection in toc}{fg=TitleFont}%
  \hypersetup{linkcolor=TitleFont}%
  \usebeamerfont{title}%
  \setbeamercolor{footnote}{fg=TitleFont}%
  \setbeamercolor{footnote mark}{fg=TitleFont}%
  \usebeamercolor[fg]{title page}%
}

\define@key{beamerframe}{title}[true]{%
  \setbeamertemplate{headline}[headline title]
  \setbeamertemplate{sidebar left}[sidebar title theme]
  \setbeamertemplate{frametitle}[frametitle title]
  \setbeamertemplate{footline}[footline off]
  \setbeamercolor{background canvas}{bg=BaseColor}%
  \setbeamercolor{section in toc}{fg=TitleFont}%
  \setbeamercolor{subsection in toc}{fg=TitleFont}%
  \hypersetup{linkcolor=TitleFont}%
  \usebeamerfont{title}%
  \setbeamercolor{footnote}{fg=TitleFont}%
  \setbeamercolor{footnote mark}{fg=TitleFont}%
  \usebeamercolor[fg]{title page}%
}
% ..............................................................................
% Actual plain environment
% This removes the left sidbar of a plain frame
% ------------------------------------------------------------------------------
\providebool{fau@blank}
\define@key{beamerframe}{blank}[true]{%
	\booltrue{fau@blank}
	\begingroup
	\beamer@plainframetrue%
	\def\beamer@frametemplate{\beamer@frametemplate@plain}
	\setlength{\hoffset}{-\beamer@leftsidebar}
	\addtolength{\textwidth}{\beamer@leftsidebar}
	\addtolength{\textwidth}{\beamer@rightmargin}
	\setlength{\hsize}{\textwidth}
	\setlength{\columnwidth}{\textwidth}
}

\apptocmd{\beamer@reseteecodes}{%
  \ifbool{fau@blank}{
    \endgroup
    \boolfalse{fau@blank}}{}
}


\setbeamertemplate{title page}{%
{\usebeamerfont{title}{\inserttitle}}\\
% if a subtitle is given insert it here
\ifx\insertsubtitle\empty\else%
{\usebeamerfont{subtitle}\parbox{0.9\textwidth}{\insertsubtitle}}%
\fi\leavevmode\\[.5em]
%
% insert authors
\ifx\insertauthor\empty\else%
{\parbox{0.9\textwidth}{
\usebeamerfont{default}\textbf{\insertauthor}}%
}\leavevmode\newline
\fi%
% insert institute name
\ifx\insertinstitute\empty\else%
    {\usebeamerfont{default}\insertinstitute}
\fi%
%
% insert date
\ifx\insertdate\empty\else%
	{\usebeamerfont{default}\insertdate}%
\fi%
%}%
}%





% ..............................................................................
% Section page
% ------------------------------------------------------------------------------

\AtBeginSection{%
{%
%\usebeamercolor[fg]{normal text}
\begin{frame}[title]{-}
\usebeamerfont{title}%
\hypersetup{linkcolor=TitleFont}%
\tableofcontents[currentsection]%
\end{frame}
}%
}%
% --------------------------------------------------------------------------

% ..............................................................................
% Boxes and list
% -------
%
% We define the bullet points for list and box behaviour.
% ------------------------------------------------------------------------------

\setbeamertemplate{itemize items}[triangle] % adapt height of itemize rectangles
\setbeamertemplate{itemize item}{\raisebox{0.22ex}{$\bullet$}\hskip0.1em}
\setbeamertemplate{itemize subitem}{\raisebox{0.22ex}{$\circ$}\hskip0.1em}
\setbeamertemplate{navigation symbols}{}  % no navigation symbols
% ------------------------------------------------------------------------------

% ..............................................................................
% Text alignemnt
% -------
%
% Adjust the space that is justed in a frame.
% ------------------------------------------------------------------------------

\setbeamersize
{
    text margin left=0cm,
    text margin right=\fau@inner@RightMargin
}
% ------------------------------------------------------------------------------


\setbeamertemplate{block begin}{%
	\vspace*{\fau@inner@YScale\dimexpr1ex}%
	\begin{beamercolorbox}[sep=\fau@inner@YScale\dimexpr5pt]{block title}
	\usebeamerfont*{block title}\insertblocktitle%
	\end{beamercolorbox}%
	\nointerlineskip%
	\usebeamerfont{block body}%
	\begin{beamercolorbox}[%
	sep=\fau@inner@YScale\dimexpr5pt
	]{block body}%
}%

\setbeamertemplate{block end}{%
\end{beamercolorbox}
\vspace*{\fau@inner@YScale\dimexpr0.2ex}
}




% ..............................................................................
% ToC
% -------
%
% We want numbered sections in Toc. Additionally we specify of shaded toc.
% ------------------------------------------------------------------------------
\setbeamertemplate{section in toc}[sections numbered]
\setbeamertemplate{subsection in toc}[subsections numbered]

\setbeamertemplate{section in toc shaded}{%
\begin{colormixin}{0!BaseColorA}%
\usebeamertemplate{section in toc}%
\end{colormixin}%
\unskip%
}

\setbeamertemplate{subsection in toc shaded}{%
\begin{colormixin}{0!BaseColorA}%
\usebeamertemplate{subsection in toc}%
\end{colormixin}%
\unskip%
}
% ..............................................................................
% Reset mode to all
\mode<all>