#! /bin/sh
# rename files to lower/upper case... 
#
# usage: 
#    move-to-lower * 
#    move-to-upper * 
# or
#    move-to-lower -R .
#    move-to-upper -R .
#

help()
{
	cat << eof
Usage: $0 [-n] [-r] [-h] files...

-n      do nothing, only see what would be done
-R      recursive (use find)
-h      this message
files   files to remap to lower case

Examples:
       $0 -n *        (see if everything is ok, then...)
       $0 *

       $0 -R .

eof
}

apply_cmd='sh'
finder='echo "$@" | tr " " "\n"'
files_only=

while :
do
    case "$1" in 
        -n) apply_cmd='cat' ;;
        -R) finder='find "$@" -type f';;
        -h) help ; exit 1 ;;
        *) break ;;
    esac
    shift
done

if [ -z "$1" ]; then
        echo Usage: $0 [-h] [-n] [-r] files...
        exit 1
fi

LOWER='abcdefghijklmnopqrstuvwxyz'
UPPER='ABCDEFGHIJKLMNOPQRSTUVWXYZ'

case `basename $0` in
        *upper*) TO=$UPPER; FROM=$LOWER ;;
        *)       FROM=$UPPER; TO=$LOWER ;;
esac

	
eval $finder | sed -n '

# remove all trailing slashes
s/\/*$//

# add ./ if there is no path, only a filename
/\//! s/^/.\//

# save path+filename
h

# remove path
s/.*\///

# do conversion only on filename
y/'$FROM'/'$TO'/

# now line contains original path+file, while
# hold space contains the new filename
x

# add converted file name to line, which now contains
# path/file-name\nconverted-file-name
G

# check if converted file name is equal to original file name,
# if it is, do not print nothing
/^.*\/\(.*\)\n\1/b

# now, transform path/fromfile\n, into
# mv path/fromfile path/tofile and print it
s/^\(.*\/\)\(.*\)\n\(.*\)$/mv \1\2 \1\3/p

' | $apply_cmd