#!/usr/bin/perl -w

# DISCLAIMER: This script should is supplied "AS IS" and its output checked
# for sanity before being used for anything important such as PartII 
# dissertations.

# This code is under the GNU Public Licence (http://www.gnu.org)
# (c) Nathan Dimmock (ned21@srcf.ucam.org) 2001-2002

use strict;
# zap an entire command (e.g. \cite{...} )
my @commands = ("label", "ref", "cite", "includegraphics", "vspace" );
# Zap words found as arguments to \begin{} and \end{} commands
my @section = ("verbatim", "itemize", "enumerate", "table", "tabular", "figure" , "narrow", "minipage", "document" );
# Ignore any text between \begin{} & \end{}
my @ignore = ( "equation", "displaymath", "eqnarray" );
my @output; 

foreach my $file (@ARGV)
{
	#print "$file\n";
	my $kill=0; #ignore everything while kill=1
	my $currentIgn="";
	#open( A, "${file}.tex" );
	open( A, "$file" );
	my @SRC = <A>;
	foreach my $line (@SRC)
	{
		if( $kill == 1) # Ignore certain sections completely
		{
			if( $line =~ /\\end{$currentIgn}/)
			{
				$kill=0;
			}
			$line =~ s/.*(\\end{$currentIgn})?//;
			next;
		}
			
		$line =~ s/%.*// ; # remove comments
		foreach my $com (@commands)
		{
			$line =~ s/\\$com.*}//g;
		}
		foreach my $sec (@section)
		{
			$line =~ s/\\.*{$sec}//g;
		}
		foreach my $ign (@ignore)
		{
			if( $line =~ /\\begin\{$ign\}/
				&& $line !~ /\\end\{$ign\}/ )
			{
				$kill=1;
				$currentIgn=$ign;
			}
			$line =~ s/\\begin{$ign}.*(\\end{$ign})?//;
		}
		$line =~ s/\\[a-zA-Z]*//g; # remove things beginning with \
		#print "$line";
		push(@output, $line);
	}
}
print @output;