#!/usr/bin/perl -w

use strict;

# For brevity, there is no error checking here.
# In Real Life[TM], you should, of course, check for errors.

my %TranslationTable = ();

# Load Translation Table
{
	open TRANSLATION_FILE, "<varchange.txt";
	while (my $trnbuf = <TRANSLATION_FILE>)
	{
		chomp $trnbuf;
		my ($currentVariableName, $newVariableName, @garbageData) = split /\:/, $trnbuf;
		$TranslationTable{$currentVariableName} = $newVariableName;
	}
	close TRANSLATION_FILE;
}

# Non-destructively modify files specified on command line
foreach my $inputFilename (@ARGV)
{
	my $outputFilename = $inputFilename . "-NEW.COB";
	open INPUT_FILE, "<$inputFilename";
	open OUTPUT_FILE, ">$outputFilename";
	while (my $inputBuffer = <INPUT_FILE>)
	{
		my $outputBuffer = $inputBuffer;
		foreach my $currentVariableName (keys %TranslationTable)
		{
			my $newVariableName = $TranslationTable{$currentVariableName};

			# Your logic will likely be more intense here
			# For example, how to confirm you are only modifying variable references?
			my $translationRegex = quotemeta $currentVariableName;
			$outputBuffer =~ s/$translationRegex/$newVariableName/ig;
		}
		print OUTPUT_FILE $outputBuffer;
	}
	close INPUT_FILE;
	close OUTPUT_FILE;
}

exit;

__END__