#!/bin/bash

#########################################################
#Script to create backups
#V0.1.0-1 -- 2021-12-05
#
#Fliegerjohn
#########################################################

#
# Description
#

#
# Usage
#

# To create a new repo
#
# ./abackup.sh 

#
# variables
#

# Path to the configfile
configdir="$HOME/.abackup"
configfile="abackup.conf"

# Hier werden die zu sichernden Ordner gespeichert
backupdirsconf="backupdirs.conf"
# Hier werden die zu ignorierende Ordner gespeichert
excludebackupdirsconf="excludebackupdirs.conf"

#
# Passwortoption
#
#For the password, several options exists:
#1 - keyfile and backup password
#2 - only keyfile
#3 - only password
pwoption=1

# Storage location keyfile
pwdir="$HOME/.keys"

# Keyfile
keyfile="abackup-secret.key"

# Path of restic installation
resticbin=`type -tp restic`

# Path to the repository
repodir=`pwd`

# Get time
datum=`date`


########################
#     Funktionen       #
########################

# Generate abackup-secret.key
abackupkeygen()  {

if [ ! -d "${pwdir}" ]
then
	mkdir -p "${pwdir}"
fi

if [ ! -e "${pwdir}/${keyfile}" ]
then
	echo "Generate abackup-secret.key at $pwdir/$keyfile"
	dd if=/dev/urandom bs=512 skip=1 count=16 > $pwdir/$keyfile
	chmod 600 $pwdir/$keyfile
else
	echo "Keyfile $pwdir/$keyfile already exists"
fi

}

# Config in datei speichern
saveconfig() {
if [[ -e "$configdir/$configfile" ]]
then
	time=`date +%+4Y-%m-%d-%H:%I:%S`
	echo "The configfile already exists, it will be copied to $configdir/confbackup/!"
	if [[ ! -d "$configdir/confbackup" ]]
	then
		mkdir $configdir/confbackup
	fi

	mv $configdir/$configfile $configdir/confbackup/abackup$time.conf
fi

# Check the configdir
if [[ ! -d "$configdir" ]]; then mkdir -p $configdir; fi

# Write config
touch "$configdir/$configfile"
echo "########################################
#Thats the configfile for abackup.
#Read the README.md vor more Informations.
#
########################################
#
#
## Location of keyfile
#
pwdir="$pwdir"
keyfile="$keyfile"

#
## Options for password
#
#For the password, several options exists:
#1 - keyfile and backup password
#2 - only keyfile
#3 - only password
pwoption="$pwoption"

#
## Path to the installation of restic
#
resticbin="$resticbin"

#
## Path to the repository
#
repodir="$repodir"


" >> $configdir/$configfile
echo "Config saved to $configdir/$configfile"

}

#
# Create new repository
#
resticrepoadd()  {

# Check if restic is installed
if [[ ! -x ${resticbin} ]]
then
    echo "Could not find restic."
    exit 1
fi

# Ask user the for the location of the repository
echo "#
##########################################################
#"
printf "Where should we create the new repo? 
Please enter the full path (default=$repodir): "
read answer_repodir

if [[ -n "$answer_repodir" ]]
then
	repodir=$answer_repodir
fi

# Check if a repository is existing. If not it creates one.
if [[ ! -d "${repodir}" ]]
then
	echo "Create repodir!"
	mkdir -p "${repodir}"
else
	echo "Repodir already exists!"
fi

# Ask which password should be used.
echo "#
##########################################################
#"
printf "For the password, several options exists:
1 - keyfile and backup password
2 - only keyfile
3 - only password

Please choose one (default=$pwoption): "
read answer_pwoption

if [[ -n "$answer_pwoption" ]]
then
	pwoption=$answer_pwoption
fi

# Start creation of repository
echo "#
##########################################################
#"
echo "Start to preparing a new repository at $datum"
case "$pwoption" in
	1)
	abackupkeygen
	$resticbin init --password-file $pwdir/$keyfile --repo $repodir
	$resticbin -r $repodir key add --password-file $pwdir/$keyfile
	$resticbin -r $repodir key list --password-file $pwdir/$keyfile
	;;

	2)
	abackupkeygen
	$resticbin init --password-file $pwdir/$keyfile --repo $repodir

	;;

	3)
	$resticbin init --repo $repodir
	;;

esac

# Save config if desired
echo "#
##########################################################
#"
printf "Do you want to save your config? (y/n)(default=y): "
read answer_saveconfig

if [[ ! -n "$answer_saveconfig" ]]
then
	answer_saveconfig=y
fi

if [[ "$answer_saveconfig" = "y" ]]
then
	echo ""
	printf "Where do you want to save the config? (default=$configdir): "
	read answer_configdir

	if [[ -n "$answer_configdir" ]]
	then
		configdir=$answer_configdir
	fi

	saveconfig

elif [[ "$saveconfig" = "n" ]]
then
	echo "Exit without saving!"
else
	echo "Wrong argument. Exit without saving!"
	exit 1
fi


}

savebackupdirs()  {
# Check the configdir

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

# Ask for the dirs to backup
printf "Please enter the dirs you want to backup: "
read answer_backupdirs
array_backupdirs=( $answer_backupdirs )

if [[ -e $configdir/$backupdirsconf ]]; then echo "Delete old $backupdirsconf and write a new one." && rm $configdir/$backupdirsconf; fi
touch $configdir/$backupdirsconf
echo "###############################################################
# Here you can write down which dirs you want to backup! #
###############################################################" >> $configdir/$backupdirsconf
for backupdir in ${array_backupdirs[*]}
do
	if [[ ! -d "$backupdir" ]]; then echo "ERROR! Cant find dir $backupdir!" && exit 1; fi
	echo $backupdir >> $configdir/$backupdirsconf
done


# Ask for the dirs to exclude
printf "Do you want tho exclude dirs? Write the paths down: "
read answer_excludebackupdirs
array_excludebackupdirs=( $answer_excludebackupdirs )

if [[ -e $configdir/$excludebackupdirsconf ]]; then echo "Delete old $excludebackupdirsconf and write a new one." && rm $configdir/$excludebackupdirsconf; fi
touch $configdir/$excludebackupdirsconf
echo "##########################################################
# Here you can write down which dirs you don't want to backup! #
##########################################################" >> $configdir/$excludebackupdirsconf
for excludebackupdir in ${array_excludebackupdirs[*]}
do
	if [[ ! -d "$excludebackupdir" ]]; then echo "ERROR! Cant find dir $excludebackupdir!" && exit 1; fi
	echo $excludebackupdir >> $configdir/$excludebackupdirsconf
done

}
#
## Create backup
#
backup()  {

echo "Let's create a backup!"

# Check if a configfile exists in the backupdir
if [[ -e "${configdir}/${backupdirsconf}" ]]
then
	echo "Take a backup of the dirs listed in $configdir/$backupdirsconf!"
	
	# Ask for the passwordoption
	# With keyfile
	if [[ "$pwoption" <  "3" ]]; then
	$resticbin -r $repodir backup --files-from $configdir/$backupdirsconf --exclude-file=$configdir/$excludebackupdirsconf --password-file="$pwdir/$keyfile"; fi
	# Without keyfile
	if [[ "$pwoption" = "3" ]]; then
	$resticbin -r $repodir backup --files-from $configdir/$backupdirsconf --exclude-file=$configdir/$excludebackupdirsconf; fi

else
	printf "There is no config for backupdirs!
Do you want to make a list of backupdirs at $configdir/$backupdirsconf?
1 - yes
2 - no, want to get it manualy
(default=1): "

	read answer_backupdirs
	echo ""

	# Set standard if input is empty
	if [[ ! -n "$answer_backupdirs" ]]
	then
		answer_backupdirs=1
	fi

	# Ask for the folders to backup
	if [[ "$answer_backupdirs" = "1" ]]
	then
		savebackupdirs
		backup

	elif [[ "$answer_backupdirs" = "2" ]]
	then
		printf "Please enter the dirs you want to backup: "
		read backupdirs

		printf "Do you want tho exclude dirs? Write the paths down: "
		read excludebackupdirs

		# Ask for the passwordoption
		# With keyfile
		if [[ "$pwoption" < "3" ]]; then
		$resticbin -r $repodir backup $backupdirs --exclude=$excludebackupdirs --password-file="$pwdir/$keyfile"; fi
		# Without keyfile
		if [[ "$pwoption" = "3" ]]; then
		$resticbin -r $repodir backup $backupdirs --exclude=$excludebackupdirs; fi
	
	else
		echo "Wrong argument. Exit!"
		exit 1
	fi
fi

}

#
## Read config
#
readconfig()  {

if [[ -e "${configdir}/${configfile}" ]]
then
	echo "There is an available config at $configdir/$configfile!"
	. $configdir/$configfile
else
	echo "There is no existing config at $configdir/$configfile!"
fi

}

#
printhelp()  {
echo "
###########################
#Use of the Backupscript: #
###########################
#
## Add a new restic-repo
#
./abackup --add-restic-repo

#
## Take a backup
#
./abackup --backup

#
## Print this help
#
./abackup --help

"
}

########################
#    Main programm     #
########################


# What is to be done
case "$1" in 
	--add-restic-repo)
		readconfig
		resticrepoadd
		exit 0
		;;

	--add-new-backupdirs)
		readconfig
		savebackupdirs
		exit 0
		;;

	--backup)
		readconfig
		backup
		exit 0
		;;

	--restore)
		echo "Later that comand will restore your data!"
		exit 0
		;;

	--help)
		printhelp
		exit 0
		;;
esac

printhelp