#! /bin/bash
# (c) Joe Klemmer <joe@webtrek.com>
# Licensed under the Public Domain.

# This script can be used to rename files to all upper case or lower case.
#
# NOTE: There is currently no error checking to make sure the target
#       directory exists.  This would be a good check to add.
#
# NOTE: The above check was implimented as a simple check of $? after
#       the cd command.

# Set the usage information.
USAGE="Usage: $0 <u|l> dir";

# Make sure that two parameters were passed on the command line.
# If not display the usage information and exit.
if [ $# -lt 2 ]; then
	echo $USAGE;
	exit 1;
fi

# Check to see which way we are converting; u -> l or l -> u.
# Throw an error if something other than "u" or "l" is passed as
# the second parameter.
# If not display the usage information and exit.
case $1 in
	"u")
		CASETO="[:upper:]"	# All upper
		CASEFROM="[:lower:]"	# All lower
		;;
	"l")
		CASETO="[:lower:]"	# All lower
		CASEFROM="[:upper:]"	# All upper
		;;
	*)
		echo $USAGE
		exit 1
esac

# Save the current directory then cd into the directory passed
# on the command line in the second parameter.  The directory
# passed must be either cannonical or relitive to the current
# directory.
CURDIR=`pwd`;
cd $2;
if [ $? -ne 0 ]; then
	echo "Target directory must be valid and either cannonical \
or relitive to the current working directory."
	exit 1
fi  

# Do the actual renaming of the files.  It is left as an excersize for the
# reader to figure out the logic used here.
for i in `ls`
do      
	UCASE=`ls $i | tr $CASEFROM $CASETO`;
	if [ $i != $UCASE ]; then
		echo "Moving $i to $UCASE";
		mv $i $UCASE 2> /dev/null;
	fi
done

# Change back to the original working directory and exit.
cd $CURDIR;
exit 0;