handouts/resources/ormc_handout.cls

% Mark's math circle handout style.
% Source is at https://git.betalupi.com/Mark/ormc-handouts
\NeedsTeXFormat{LaTeX2e}
\ProvidesClass{ormc_handout}[2023/05/25 2.0.0 ORMC Handout]


% ------------------ %
% Option Definitions %
% ------------------ %

\newif{\if@solutions} % If false, solutions and instructor notes are hidden.
\newif{\if@singlenumbering} % If true, the same counter is used for all objects.
\newif{\if@nopagenumber} % If true, don't number pages.
\newif{\if@shortwarning} % If true, show a smaller solutions warning
\newif{\if@nowarning} % If true, do not show solution warning

\DeclareOption{solutions}{\@solutionstrue}
\DeclareOption{nosolutions}{\@solutionsfalse}
\DeclareOption{multinumbering}{\@singlenumberingfalse}
\DeclareOption{singlenumbering}{\@singlenumberingtrue}
\DeclareOption{pagenumber}{\@nopagenumberfalse}
\DeclareOption{nopagenumber}{\@nopagenumbertrue}
\DeclareOption{longwarning}{\@shortwarningfalse}
\DeclareOption{shortwarning}{\@shortwarningtrue}
\DeclareOption{showwarning}{\@nowarningfalse}
\DeclareOption{hidewarning}{\@nowarningtrue}
\DeclareOption*{\ClassWarning{ormc_handout}{\CurrentOption ignored}}

\ExecuteOptions{
	solutions,
	multinumbering,
	pagenumber,
	longwarning,
	yeswarning
}

\ProcessOptions

% Hack to allow script option override.
% To force a build with solutions, compile a file containing the following:
%	`\def\argYesSolutions{1}\input{<target file>}`
\ifdefined\argYesSolutions\@solutionstrue\fi
\ifdefined\argNoSolutions\@solutionsfalse\fi








\RequirePackage{etoolbox}

% Based on article class
\LoadClass{article}
\undef\maketitle
\undef\section

\newcommand\sbullet[1][.5]{\mathbin{\vcenter{\hbox{\scalebox{#1}{$\bullet$}}}}}

\renewcommand{\labelitemi}{$\sbullet$}
\renewcommand{\labelitemii}{$\cdot$}
\renewcommand{\labelenumi}{\textbf{\Alph{enumi}:}}










% ------------- %
% Package Setup %
% ------------- %


% Set up page geometry.
% MUST BE DONE FIRST!
\RequirePackage{geometry}
\geometry{
	paper      = letterpaper,
	top        = 25mm,
	bottom     = 30mm,
	left       = 30mm,
	right      = 30mm,
	headheight = 75mm,
	footskip   = 15mm,
	headsep    = 75mm,
}

\RequirePackage{enumitem}  % List customization
\RequirePackage{xcolor}    % For colored text
\RequirePackage{tikz}      % Used by \boxlinehack
\RequirePackage{comment}   % Used to hide solutions
\RequirePackage{tcolorbox} % For solution boxes
\tcbuselibrary{breakable}  % Allows tcolorboxes to break across pages

\RequirePackage[ % Provides \say{} for quoted text.
	left = ``,
	right = '',
	leftsub = `,
	rightsub = '
]{dirtytalk}

% Not used by this class, but likely to be used in documents
\RequirePackage{amsmath}
\RequirePackage{amssymb}
\RequirePackage{tabto}
\TabPositions{1cm, 2cm, 3cm, 4cm, 5cm, 6cm, 7cm, 8cm}








% ----------- %
% Style Setup %
% ----------- %

\if@nopagenumber
	\pagestyle{empty}
\else
	\pagestyle{plain}
\fi

\renewcommand*{\thefootnote}{\arabic{footnote}}
\setlength{\parindent}{0mm}
\setlist{noitemsep, topsep=0mm}
\raggedright
\frenchspacing












% ------------- %
% Handout Title %
% ------------- %

% These are in LaTeX by default, but we don't use them here.
% Undef them to avoid confusion.
\undef\thanks
\undef\author
\undef\date

% Additional title parameters
\def\@subtitle{\relax}
\def\@uptitlel{\relax}
\def\@uptitler{\relax}
\newcommand{\subtitle}[1]{\gdef\@subtitle{#1}}
\newcommand{\uptitlel}[1]{\gdef\@uptitlel{#1}}
\newcommand{\uptitler}[1]{\gdef\@uptitler{#1}}

\newcommand{\@shortwarning}{
	\begin{tcolorbox}[colback=white, colframe=red]
		\large\centering\color{red}
		\textbf{Instructor's Handout} \par
	\end{tcolorbox}
}

\newcommand{\@longwarning}{
	\begin{tcolorbox}[colback=white, colframe=red]
		\color{red}
		\begingroup
			\large\centering
			\textbf{Instructor's Handout} \par
		\endgroup
		\vspace{1ex}
		This file contains solutions and notes. \par
		Compile with the ``nosolutions'' flag before distributing. \par
	\end{tcolorbox}
}

\newcommand{\maketitle}{
	\begingroup
	\centering
	\begin{minipage}{0.7\textwidth}
		\centering

		% Left and right headers (uptitle)
		\def\uptitle{%
			\if\@uptitlel\relax\else\textsc{\@uptitlel}\fi \hfill~%
			\if\@uptitler\relax\else\textsc{\@uptitler}\fi \par
		}
		\if\@uptitlel\relax % If neither header is defined,
		\if\@uptitlel\relax % don't insert an upper title.
			\def\@uptitle{\relax}
		\fi\fi\uptitle{}

		% Main title
		\rule{\linewidth}{0.2mm} \par
		\huge \@title \par \normalsize
		\vspace{1ex} \@subtitle \par
		\rule{\linewidth}{0.2mm} \par

		% Solution warning
		\if@nowarning\else\if@solutions%
			\if@shortwarning \@shortwarning%
			\else \@longwarning%
		\fi\fi\fi
	\end{minipage} \par
	\vspace{2ex}
	\endgroup
}








% ---------------- %
% Handout Sections %
% ---------------- %

% Helper command that creates a label with custom text.
% Аrgs: label name, custom text
\newcommand{\@customlabel}[2]{%
	\protected@write\@auxout{}{\string\newlabel{#1}{{#2}{}}}%
}

\newcounter{section_counter}
\NewDocumentCommand{\section}{ m d<> }{
	\stepcounter{section_counter}
	\vspace{8mm}
	{\bf\Large \hfill Part \arabic{section_counter}\IfNoValueF{#1}{: #1} \hfill}
	\IfNoValueF{#2}{\@customlabel{#2}Part \arabic{section_counter}} \\*
	\vspace{2mm}
}

% Generic object.
% Same format as \problem, \theorem, etc, but has no counter.
\NewDocumentCommand{\generic}{ m d<> }{
	\vspace{3mm}
	{\bf\normalsize #1} \\*
	\IfNoValueF{#2}{\@customlabel{#2}{#1}}
}

% Make a new secion type.
% Args: command, counter, title.
\newcommand\@newobj[3]{
	\NewDocumentCommand{#1}{ m d<> }{
		\stepcounter{#2}
		\generic{#3 \arabic{#2}:\IfNoValueF{##1}{ ##1}}
		\IfNoValueF{##2}{\@customlabel{##2}{#3 \arabic{#2}}}
	}
}

\if@singlenumbering
	\newcounter{object_counter}
	\def\@problemcounter{object_counter}

	\@newobj{\definition}{object_counter}{Definition}
	\@newobj{\theorem}{object_counter}{Theorem}
	\@newobj{\proposition}{object_counter}{Proposition}
	\@newobj{\example}{object_counter}{Example}
\else
	\newcounter{problem_counter}
	\newcounter{theorem_counter}
	\newcounter{definition_counter}
	\newcounter{example_counter}
	\newcounter{proposition_counter}
	\def\@problemcounter{problem_counter}

	\@newobj{\definition}{definition_counter}{Definition}
	\@newobj{\theorem}{theorem_counter}{Theorem}
	\@newobj{\proposition}{proposition_counter}{Proposition}
	\@newobj{\example}{example_counter}{Example}
\fi

% These must be defined manually, since
% problems and problemparts use two counters.
\newcounter{problempartcounter}
\NewDocumentCommand{\problem}{ m d<> }{
	\setcounter{problempartcounter}{0}
	\stepcounter{\@problemcounter}
	\generic{Problem \arabic{\@problemcounter}:\IfNoValueF{#1}{ #1}}
	\IfNoValueF{#2}{\@customlabel{#2}{Problem \arabic{\@problemcounter}}}
}
\NewDocumentCommand{\problempart}{ m d<> }{
	\stepcounter{problempartcounter}
	\generic{Part \arabic{problempartcounter}:\IfNoValueF{#1}{ #1}}
	\IfNoValueF{#2}{\@customlabel{#2}{Problem \arabic{\@problemcounter}.\arabic{problempartcounter}}}
}








% ---------------- %
% Box environments %
% ---------------- %

% Keep track of the current background color.
% Useful for transparent tikz drawings.
\def\ORMCbgcolor{white}

% Make a box environment.
% These can safely be nested.
% Args: name, title, back color, frame color.
\newcommand{\@makeORMCbox}[4]{
	\newenvironment{#1}{
		% \linehack draws a line across a tcolorbox.
		% tcolorbox only supports two sections, but
		% this hack allows us to have more.
		\def\linehack{
			\begin{tikzpicture}
				\path[use as bounding box]
					(0, 0) --
					(\linewidth, 0);

				\draw[color=#4, dashed, dash phase=1mm]
					(0 - \kvtcb@leftlower-\kvtcb@boxsep, 0) --
					(\linewidth + \kvtcb@rightlower + \kvtcb@boxsep, 0);
			\end{tikzpicture} \par
			\vspace{2mm}
		}

		% Keep track of the current background color.
		% Useful for transparent tikz drawings.
		\def\ORMCbgcolor{#3}

		\begin{tcolorbox}[
			breakable,
			colback=#3,
			colframe=#4,
			title={\textbf{#2}}
		]
		\raggedright
	} {
		\end{tcolorbox}
	}
}

\@makeORMCbox{examplesolution}{Example Solution}{white}{grey!75!black}

\if@solutions
	\@makeORMCbox{solution}{Solution}{red!5!white}{red!75!black}
	\@makeORMCbox{instructornote}{Note for Instructors}{cyan!5!white}{cyan!75!black}
\else
	\excludecomment{solution}
	\excludecomment{instructornote}
\fi








% -------------------- %
% Misc helper commands %
% -------------------- %

\NewDocumentCommand{\note}{ d[] m }{
	\IfNoValueTF{#1}
		{\textcolor{gray}{#2}}
		{\textcolor{gray}{\textit{#1:} #2}}
	\par
}
\newcommand{\hint}[1]{\note[Hint]{#1}}