% Unified public entry for the IMPE template system.
% This file wires the stable subsystem entries together.

\RequirePackage{expl3}
\RequirePackage{xparse}
\RequirePackage{import}

\hfuzz=20pt
\hbadness=10000
\vbadness=10000
\emergencystretch=3em

\makeatletter
\@ifundefined{ifNextSystemInstalled}
  {\newif\ifNextSystemInstalled\NextSystemInstalledfalse}
  {}
\makeatother

\ifNextSystemInstalled
  \input{core/layout/impe-layout-system.tex}
  \input{core/fonts/impe-fonts-system.tex}
  \input{core/features/impe-features-system.tex}
\else
  \subimport{../layout/}{impe-layout-system.tex}
  \subimport{../fonts/}{impe-fonts-system.tex}
  \subimport{../features/}{impe-features-system.tex}
\fi

\ExplSyntaxOn

\bool_new:N \g__nextsystem_installed_bool
\cs_if_exist:NTF \ifNextSystemInstalled
  {
    \ifNextSystemInstalled
      \bool_gset_true:N \g__nextsystem_installed_bool
    \else
      \bool_gset_false:N \g__nextsystem_installed_bool
    \fi
  }
  { \bool_gset_false:N \g__nextsystem_installed_bool }

\tl_new:N \l__nextsystem_layout_tl
\tl_new:N \l__nextsystem_globalfonts_tl
\tl_new:N \l__nextsystem_fonts_tl
\tl_new:N \l__nextsystem_features_tl
\tl_new:N \l__nextsystem_ui_tl
\tl_new:N \l__nextsystem_effective_layout_tl
\tl_new:N \l__nextsystem_effective_globalfonts_tl
\bool_new:N \g__nextsystem_class_defaults_loaded_bool
\bool_new:N \g__nextsystem_ui_loaded_bool

\providecommand{\NextHeaderTitleText}{}
\providecommand{\HeaderTitle}[1]{\renewcommand{\NextHeaderTitleText}{#1}}
\providecommand{\NextHeaderStyleText}{running}
\providecommand{\HeaderStyle}[1]{%
  \renewcommand{\NextHeaderStyleText}{#1}%
  \ifcsname NextFeatureHeadersApply\endcsname
    \NextFeatureHeadersApply
  \fi
}

\makeatletter
\providecommand{\NextHeaderTitleFromTitleText}{}
\providecommand{\NextHeaderTitleFirstLine}[1]{%
  \NextHeaderTitleFirstLineAux#1\\\@nil
}
\def\NextHeaderTitleFirstLineAux#1\\#2\@nil{#1}
\providecommand{\NextHeaderTitleContent}{%
  \ifx\NextHeaderTitleText\@empty
    \NextHeaderTitleFromTitleText
  \else
    \NextHeaderTitleText
  \fi
}
\providecommand{\NextRunningHeaderText}{}
\providecommand{\NextRunningHeaderContent}{\NextRunningHeaderText}
\providecommand{\NextSetRunningHeader}[1]{\gdef\NextRunningHeaderText{#1}}
\@ifclassloaded{beamer}
  {}
  {%
    \let\NextSystemOriginalTitle\title
    \renewcommand{\title}[1]{%
      \NextSystemOriginalTitle{#1}%
      \gdef\NextHeaderTitleFromTitleText{\NextHeaderTitleFirstLine{#1}}%
    }%
  }
\makeatother

\cs_new_protected:Npn \__nextsystem_resolve_defaults:
  {
    \tl_set_eq:NN \l__nextsystem_effective_layout_tl \l__nextsystem_layout_tl
    \tl_set_eq:NN \l__nextsystem_effective_globalfonts_tl \l__nextsystem_globalfonts_tl

    \tl_if_blank:VT \l__nextsystem_effective_layout_tl
      {
        \cs_if_exist:NT \NextDefaultLayout
          { \tl_set:Nx \l__nextsystem_effective_layout_tl { \NextDefaultLayout } }
      }

    \tl_if_blank:VT \l__nextsystem_effective_globalfonts_tl
      {
        \cs_if_exist:NT \NextDefaultGlobalFonts
          { \tl_set:Nx \l__nextsystem_effective_globalfonts_tl { \NextDefaultGlobalFonts } }
      }
  }

\cs_new_protected:Npn \__nextsystem_apply_ui:
  {
    \bool_if:NF \g__nextsystem_ui_loaded_bool
      {
        \cs_if_exist:NTF \NextSystemUiTag
          { \tl_set:Nx \l__nextsystem_ui_tl { \NextSystemUiTag } }
          { \tl_set:Nn \l__nextsystem_ui_tl { en } }

        \str_if_eq:VnT \l__nextsystem_ui_tl { zh }
          {
            \bool_if:NTF \g__nextsystem_installed_bool
              { \input{core/system/impe-ui-zh-internal.tex} }
              {
                \cs_if_exist:NTF \NextSystemRoot
                  { \expandafter\subimport\expandafter{\NextSystemRoot core/system/}{impe-ui-zh-internal.tex} }
                  { \subimport{./}{impe-ui-zh-internal.tex} }
              }
          }
        \bool_gset_true:N \g__nextsystem_ui_loaded_bool
      }
  }

\cs_new_protected:Npn \__nextsystem_apply_class_defaults:
  {
    \bool_if:NF \g__nextsystem_class_defaults_loaded_bool
      {
        \cs_if_exist:NT \NextDefaultLayout
          {
            \tl_set:Nx \l_tmpa_tl { \NextDefaultLayout }
            \tl_if_blank:VF \l_tmpa_tl
              { \exp_args:NV \UseLayout \l_tmpa_tl }
          }

        \cs_if_exist:NT \NextDefaultGlobalFonts
          {
            \tl_set:Nx \l_tmpa_tl { \NextDefaultGlobalFonts }
            \tl_if_blank:VF \l_tmpa_tl
              { \exp_args:NV \UseFonts \l_tmpa_tl [global] }
          }

        \__nextsystem_apply_ui:
        \bool_gset_true:N \g__nextsystem_class_defaults_loaded_bool
      }
  }

\keys_define:nn { nextsystem/setup }
  {
    layout .tl_set:N = \l__nextsystem_layout_tl,
    globalfonts .tl_set:N = \l__nextsystem_globalfonts_tl,
    mainfonts .meta:n = { globalfonts = {#1} },
    fonts .tl_set:N = \l__nextsystem_fonts_tl,
    features .tl_set:N = \l__nextsystem_features_tl,
  }

\cs_new_protected:Npn \__nextsystem_setup_apply:
  {
    \__nextsystem_resolve_defaults:

    \tl_if_blank:VF \l__nextsystem_effective_layout_tl
      { \exp_args:NV \UseLayout \l__nextsystem_effective_layout_tl }

    \tl_if_blank:VF \l__nextsystem_effective_globalfonts_tl
      { \exp_args:NV \UseFonts \l__nextsystem_effective_globalfonts_tl [global] }

    \tl_if_blank:VF \l__nextsystem_fonts_tl
      { \exp_args:NV \UseFonts \l__nextsystem_fonts_tl }

    \__nextsystem_apply_ui:

    \tl_if_blank:VF \l__nextsystem_features_tl
      { \exp_args:NV \UseFeatures \l__nextsystem_features_tl }
  }

\NewDocumentCommand{\UseTemplateSet}{m}
  {
    \tl_clear:N \l__nextsystem_layout_tl
    \tl_clear:N \l__nextsystem_globalfonts_tl
    \tl_clear:N \l__nextsystem_fonts_tl
    \tl_clear:N \l__nextsystem_features_tl
    \keys_set:nn { nextsystem/setup } {#1}
    \__nextsystem_setup_apply:
  }

\NewDocumentCommand{\UseNextSystem}{m}
  { \UseTemplateSet{#1} }

\NewDocumentCommand{\UseGlobalFonts}{m}
  { \UseFonts{#1}[global] }

\NewDocumentCommand{\UseGlobalFont}{m}
  { \UseFont{#1}[global] }

\NewDocumentCommand{\UseMainFonts}{m}
  { \UseGlobalFonts{#1} }

\NewDocumentCommand{\UseMainFont}{m}
  { \UseGlobalFont{#1} }

\NewDocumentCommand{\UseLocalFonts}{m}
  { \UseFonts{#1}[local] }

\NewDocumentCommand{\UseLocalFont}{m}
  { \UseFont{#1}[local] }

\ExplSyntaxOff

\makeatletter
\providecommand{\@subtitle}{}
\providecommand{\subtitle}[1]{\gdef\@subtitle{#1}}
\providecommand{\NextTitleFont}{\normalfont\LARGE\bfseries}
\providecommand{\NextSubtitleFont}{\normalfont\large}
\providecommand{\NextTitleAuthorFont}{\normalfont\large}
\providecommand{\NextTitleDateFont}{\normalfont\large}
\@ifundefined{chapter}
  {\providecommand{\NextTitleTopSkip}{2em}}
  {\providecommand{\NextTitleTopSkip}{0.18\textheight}}
\providecommand{\NextTitleBottomSkip}{1.5em}
\providecommand{\NextTitleBlock}{%
  \begin{center}%
    {\NextTitleFont \@title \par}%
    \ifx\@subtitle\@empty
    \else
      \vskip 0.5em%
      {\NextSubtitleFont \@subtitle \par}%
    \fi
    \vskip 1.5em%
    {\NextTitleAuthorFont
      \lineskip 0.5em%
      \begin{tabular}[t]{c}%
        \@author
      \end{tabular}\par}%
    \vskip 1em%
    {\NextTitleDateFont \@date \par}%
  \end{center}%
}
\@ifclassloaded{beamer}
  {}
  {%
    \def\@maketitle{%
      \newpage
      \null
      \vspace*{\NextTitleTopSkip}%
      \NextTitleBlock
      \vskip \NextTitleBottomSkip%
    }%
    \renewcommand{\maketitle}{%
      \par
      \begingroup
        \renewcommand\thefootnote{\@fnsymbol\c@footnote}%
        \def\@makefnmark{\rlap{\@textsuperscript{\normalfont\@thefnmark}}}%
        \long\def\@makefntext##1{\parindent 1em\noindent
          \hb@xt@1.8em{\hss\@textsuperscript{\normalfont\@thefnmark}}##1}%
        \if@twocolumn
          \ifnum \col@number=\@ne
            \@maketitle
          \else
            \twocolumn[\@maketitle]%
          \fi
        \else
          \newpage
          \global\@topnum\z@
          \@maketitle
        \fi
        \thispagestyle{plain}\@thanks
      \endgroup
      \setcounter{footnote}{0}%
      \global\let\thanks\relax
      \global\let\maketitle\relax
      \global\let\@maketitle\relax
      \global\let\@thanks\@empty
      \global\let\@author\@empty
      \global\let\@date\@empty
      \global\let\@title\@empty
      \global\let\@subtitle\@empty
      \global\let\title\relax
      \global\let\subtitle\relax
      \global\let\author\relax
      \global\let\date\relax
      \global\let\and\relax
    }%
  }
\makeatother

\ExplSyntaxOn

\__nextsystem_apply_class_defaults:

\ExplSyntaxOff