Shell case statement

Shell case statement function decompress_packet () (echo "+ ----------------------------------------- +" echo "| Decompress $1 now" echo "+ response +" ftype = 'file "$1" 'case "$ ftype" in "$1: zip archive "*) unzip" $1 ";" $1: gzip compressed "*) if ['expr" $1 ":". *. tar. * "']; then tar-xzf $1 else gzip-d" $1 "fi;" $1: bzip2 compressed "*) if ['expr" $1 ": ". *. tar. * "']; then tar-xjf $1 else bunzip2" $1 "fi;" $1: POSIX tar archive "*) tar-xf" $1 ";; *) echo "$1 is unknow compress format"; esac)