#!/bin/bash

sudo echo ">>> Initialising"

PREFIX=$2

if [[ ! "$PREFIX" == "" ]]; then
	PREFIX=$2-
fi

if [[ `id -u` == 0 ]]; then
	echo "WARNING: Running as root? This might not be what you want..."
fi

ROOT=~/.backups/disk

if [[ ! -d $ROOT ]]; then
	mkdir -p $ROOT
fi

if stat "$1"; then
	OUTPUT=$ROOT/$PREFIX`basename $1`-`date +%Y-%m-%d-%H%M%S`.disk
	sudo umount "$1" &> /dev/null
	echo ">>> Will backup disk '$1' to file $OUTPUT"
	read -p "Is this okay (y/N)? " -n 1 -r
	echo 
	if [[ $REPLY =~ ^[Yy]$ ]]; then
		set -e
		set -o pipefail
		if sudo dd "if=$1" conv=sync,noerror status=progress | gzip -9 -c | openssl aes-192-cbc -salt -e > $OUTPUT; then
			echo ">>> Calculating hash"
			sha256sum $OUTPUT > $OUTPUT.sha256
			echo ">>> Signing image"
			gpg --detach-sign -o $OUTPUT.sig $OUTPUT
			echo ">>> Setting permissions"
			sudo chmod 0444 $OUTPUT
			sudo chmod 0444 $OUTPUT.sha256
			sudo chmod 0444 $OUTPUT.sig
			echo ">>> Done"
		else
			echo "ERROR - Stopping"
		fi
	else
		echo "Doing nothing"
	fi
else
	echo "ERROR - File not found"
fi