decompress.sh

#!/bin/bash
FILE="$1"
TYPE="$(file $1)"
if ! echo "$TYPE" | grep "compressed data" >/dev/null 2>&1; then
	echo "Plik $FILE nie jest zkompressowany";
	exit 1
fi

case "$FILE" in
	*.zip)
		unzip "$FILE"
		;;
	*.tar | *.tar.gz | *.tar.xz)
		tar xf "$FILE"
		;;
	*)
		echo "unrecognized format"
		exit 1
		;;
esac