#!/bin/sh

# get command name - do we make or unpack archives?

isunpack=unpack
case "`basename $0`" in
unztar)
	;;
ztar)
	isunpack=""
	;;
*)
	;;
esac

# usage
usage () {
  name="`basename $0`"
  cat 1>&2 << END
$name [opts] archive-files
  [opts]:
  -t      list archive contents
  -x      extract archive contents
  -nodir  extract to current directory (otherwise use path and basename of
  	  archive" as directory path)
  -h	  list help information and exit
  archive-files: extensions
  .tar                           plain tar files
  .tar.Z, .tz, .taz, .TZ, .TAZ   compressed tar files
  .tar.gz, .tgz, .TGZ            GNU compressed tar files
  .zip, .ZIP                     ZIP files
END
  exit
}

# process options upto unrecognised
minus=minus
makedir=makedir
while [ -n "$minus" ]; do
	case "$1" in
	-gnu)
		compress=gzip
		shift
		;;
	-zip)
		compress=zip
		shift
		;;
	-t)
		info=info
		shift
		;;
	-x)
		extract=extract
		shift
		;;
	-c)
		archive=archive
		shift
		;;
	-nodir)
		makedir=""
		;;
	-h | --help | -help)
		usage
		;;
	-*)
		echo "[unknown option $1]"
		usage
		;;
	*)
		minus=""
		;;
	esac
done

if [ -n "$info" ]; then
    # content of archives
    for f in "$@"; do
	echo "File ${f}:"
	case "$f" in
	*.tar)
		tar tvf "$f"
		;;
	*.tar.Z | *.tz | *.TZ | *.taz | *.TAZ)
		zcat < "$f" | tar tvf -
		;;
	*.tar.gz | *.tgz | *.TGZ)
		gzcat < "$f" | tar tvf -
		;;
	*.zip)
		zipinfo -lzhT "$f"
		;;
	*)
		echo "[unrecognised file format for $0]"
		;;
	esac
	echo ""
    done
elif [ -n "$extract" ]; then
    # extract from the archive
    for f in "$@"; do
	echo "File ${f}:"
	case "$f" in
	# plain tar
	*.tar)	    compress=cat   ; extn='\.tar'     ; tar="tar xvf -" ;;
	# compressed tar
	*.tar.Z)    compress=zcat  ; extn='\.tar\.Z'  ; tar="tar xvf -" ;;
	*.tz)       compress=zcat  ; extn='\.tz'      ; tar="tar xvf -" ;;
	*.TZ)       compress=zcat  ; extn='\.TZ'      ; tar="tar xvf -" ;;
	*.taz)      compress=zcat  ; extn='\.taz'     ; tar="tar xvf -" ;;
	*.TAZ)      compress=zcat  ; extn='\.TAZ'     ; tar="tar xvf -" ;;
	# gnu compressed tar
	*.tar.gz)   compress=gzcat ; extn='\.tar\.gz' ; tar="tar xvf -" ;;
	*.tgz)      compress=gzcat ; extn='\.tgz'     ; tar="tar xvf -" ;;
	*.TGZ)      compress=gzcat ; extn='\.TGZ'     ; tar="tar xvf -" ;;
	# zip
	*.zip)      zip=unzip ; extn='\.zip' ;;
	*.ZIP)      zip=unzip ; extn='\.ZIP' ;;
	# anything else is unrecognised
	*)	echo "[unrecognised file format for $0]"
		;;
	esac

	if [ -n "$makedir" ] && [ -n "$extn" ]; then
	    dir=`echo "$f" | sed -e "s/$extn$//"`
	fi

	if [ -n "$tar" ]; then
	    # tar format
	    if [ -n "$dir" ]; then
		if [ -d "$dir" ] || mkdir "$dir"; then
		    echo "unpacking $f to directory $dir"
		    $compress "$f" | ( cd $dir; $tar )
		else
		    echo "[directory $dir inaccessible, cannot unpack $f]"
		    $compress "$f" | $tar
		fi
	    else
		echo "unpacking $f locally"
		$compress "$f" | $tar
	    fi
	elif [ -n "$zip" ]; then
	    # zip format
	    if [ -n "$dir" ]; then
		if [ -d "$dir" ] || mkdir "$dir"; then
		    echo "unpacking to directory $dir"
		    unzip -ov "$f" -d "$dir"
		else
		    echo "[directory $dir inaccessible, cannot unpack $f]"
		fi
	    else
		echo "unpacking $f locally"
		unzip -ov "$f"
	    fi
	fi
	echo ""
    done
elif [ -n "$archive" ]; then
    echo "[archive creation not supported in $0]"
fi