#!/bin/sh

###########################################################################
# Shell script to remove all but the arguments on the commandline,
# assuming that you're removing stuff from the current dir.

VER=1.03
PROG=`basename $0`

# print info and die
usage ()
{
    cat << ENDUSAGE

ICCE Directory Cleaner $VER
Copyright (c) K. Kubat (karel@icce.rug.nl) / ICCE 1995. All rights reserved.
Another MegaHard Production!

Usage: keep [-t] [-v] [-rf] file(s)
where:
    -t      : (optional) flag, tryout mode -- must be first argument
    -v      : (optional) flag, increases verbosity
    -r      : (optional) flag, specifying recursive removal of files
    -f      : (optional) flag, specifying forced removal of files
    file(s) : files to keep, others are removed
              the files must be in the current directory
ENDUSAGE
    exit 1
}

# print error msg and die
error ()
{
    echo $PROG: $*
    exit 1
}

# verbose message
chat ()
{
    if [ "$VERBOSE" != "" ] ; then
	echo keep: $@
    fi
}

############################################################################
# main starts here

# assume options are off
RECURSIVE=""
FORCED=""
TRYOUT=no
VERBOSE=""

# parse flags
moreargs=yes
while [ $moreargs = yes ] ; do
    case $1 in
	-t )
	    TRYOUT=yes
	    chat "tryout mode"
	    shift
	    ;;
	-rf )
	    RECURSIVE=-r
	    FORCED=-f
	    chat "recursive and forced removal"
	    shift
	    ;;
	-fr )
	    RECURSIVE=-r
	    FORCED=-f
	    chat "recursive and forced removal"
	    shift
	    ;;
	-r )
	    RECURSIVE=-r
	    chat "recursive removal"
	    shift
	    ;;
	-f )
	    FORCED=-f
	    chat "forced removal"
	    shift
	    ;;
	-v )
	    VERBOSE=yes
	    shift
	    ;;
	-* )
	    error no such flag $1 defined, -r -f -fr -rf -v supported only
	    ;;
	* )
	    moreargs=no
	    ;;
    esac	    
done

# any arguments? 
if [ "$1" = "" ] ; then
    usage
fi

# build list of files]
for f in $* ; do
    FILES=`echo $FILES $f | sed 's/\///'`
done
chat "all files or directories to keep: $FILES"

# check that all files are real ones
for f in $FILES ; do
    if [ ! -f $f -a ! -d $f ] ; then
	error specified file or directory $f not found, cannot keep it
    fi
done

# get a listing of cur dir
LST=`ls -1`

# if not recursive removal: keep only true files in the list
if [ "$RECURSIVE" != "-r" ] ; then
    for f in $LST ; do
        if [ -f $f ] ; then
            NEWLIST=`echo $NEWLIST $f`
        fi
    done
    LST=$NEWLIST
fi

for f in $FILES ; do
    LST=`echo $LST | tr ' ' '\n' | grep -v "^$f$"`
done
chat "list of files to remove: $LST"

if [ "$LST" = "" ] ; then
    error "no files to remove"
fi

if [ "$TRYOUT" = "yes" ] ; then
    echo 'Files that would be removed:'
    echo "$LST"
else    
    rm $RECURSIVE $FORCED `echo "$LST"` \
	|| error 'problem while removing files'
fi

exit 0