% \subsubsection{Feedback}
% \DescribeEnv{feedback}{An initially hidden environment that uncovers itself at an appropriate time.}
% New Validator rewrite code added by Jason Nowell. Original code
% orovided by Jim Fowler Validator is an environment designed to run a
% custom check on answers (usually) using javascript code.
%
% Define a placeholder command for validator and feedback.
%    \begin{macrocode}
%<*classXimera>
\newcommand{\PH@Command}{}
%    \end{macrocode}
% Validator should take an argument and detokenize it and display it
% at the start of the environment. The original Validator environment
% had everything framed in an mbox; presumably to make the text look
% a bit nicer, although this seems redundant with |texttt|. It
% shouldn't cause any harm so I have left it in for now.
%    \begin{macrocode}
\newenvironment{validator}[1][]{
	\def\PH@Command{#1}% Use PH@Command to hold the content and be a target for "\expandafter" to expand once.
	\mbox{\texttt{\detokenize\expandafter{\PH@Command}}}% Now expand PH@Command once and then detokenize. 
	}{}
%    \end{macrocode}
% First, if it's a handout, we want feedback to eat everything and
% then disappear entirely. So we do this:
%    \begin{macrocode}
\ifhandout%
\newenvironment{feedback}
               {%
		 \setbox0\vbox\bgroup
	       }
               {%
		 \egroup
	       }               
%    \end{macrocode}
% If this isn't a handout, then we want to display the Feedback by
% using a label, positioned and formated as a |\item| in a
% trivlist. It is important that we also detokenize the content of
% the optional argument, as it is likely to contain javascript or
% other code that latex won't be able to make sense of.
%    \begin{macrocode}
\else
%    \end{macrocode}
%    \begin{macrocode}
\newenvironment{feedback}[1][attempt]{

	\def\PH@Command{#1}% Use PH@Command to hold the content and be a target for "\expandafter" to expand once.
	
	\begin{trivlist}% Begin the trivlist to use formating of the "Feedback" label.
	\item[\hskip \labelsep\small\slshape\bfseries Feedback% Format the "Feedback" label. Don't forget the space.
	(\texttt{\detokenize\expandafter{\PH@Command}}):% Format (and detokenize) the condition for feedback to trigger
	\hspace{2ex}]\small\slshape% Insert some space before the actual feedback given.
	}{
	\end{trivlist}	
	}

\fi
%</classXimera>
%    \end{macrocode}
% Feedback environments take an optional parameter (which describes
% when the feedback is to be provided)
%    \begin{macrocode}
%<*htXimera>
\def\feedback{\@ifnextchar[{\@feedbackcode}{\@feedbackattempt}}
\def\@feedbackattempt{\@feedbackcode[attempt]}
\def\@feedbackcode[#1]{\stepcounter{identification}%
\ifvmode \IgnorePar\fi \EndP%
\ifthenelse{\equal{#1}{attempt}}{\HCode{<div class="feedback" data-feedback="attempt" id="feedback\arabic{identification}">}}%
{\ifthenelse{\equal{#1}{correct}}{\HCode{<div class="feedback" data-feedback="correct" id="feedback\arabic{identification}">}}%
{\HCode{<div class="feedback" data-feedback="script" id="feedback\arabic{identification}"><script type="text/javascript">function feedback\arabic{identification}() }\{\HCode{ return \detokenize{#1}; }\}\HCode{</script>}}}}
\def\endfeedback{\HCode{</div>}\IgnoreIndent}
%</htXimera>
%    \end{macrocode}