#!/bin/bash
##Simple script to run Restic backups

help()
{
    echo "Kumonoboru - Back up important location to the B2 cloud using Restic." 
    echo "  {-c|--clean}                 -- Force prune of the remote repositories"
    echo "  {-r|--repository} repository -- Only backup the specified repository."
    echo "  {-l|--limit} #[Kbps]         -- Limit upload & download speed"
    echo "  {-v|--verbose}	       -- Print debug messages"
    echo "  {-h|--help}                  -- Print this help message and exit"
    echo "Available repositories:"
    echo "Gerbil-TK             Photos 		      (path: /var/Red-Vol/Media/Pictures)"
    echo "Pukeko-XYZ-Containers Containers	      (path: /var/Red-Vol/Media/Containers)"
    echo "Pukeko-XYZ-Cloud      Data from all devices   (path: /var/Red-Vol/Media/Cloud)"
    exit 0
}
#Pass arguments to the script
flags()
{
    #This is utterly useless
    if [[ $# == "0" ]]; then
	    :
    fi
    while test $# -gt 0
    do
        case "$1" in
	(-c|--clean)
	    export CLEAN="1"
	    shift;;
        (-r|--repository)
	    shift
	    export REPOSITORY="$1"
	    shift;;
        (-l|--limit)
	    shift
	    export BWLIMIT="$1"
	    shift;;
        (-h|--help)
	    help;;
        (*) help;;
        esac
    done
}
flags "$@"

#Defaults
if [[ -z $BWLIMIT ]]; then
	export BWLIMIT="0"
else
    echo -e "Bandwidth will be limited to" "$BWLIMIT Kbps" 
fi
if [[ -n $CLEAN ]]; then
    echo -e "Cleaning will take place per request."
fi
if [[ -n $REPOSITORY ]]; then
	    echo -e "Will only process repository" "$1"
fi	    

export B2_ACCOUNT_ID=8582a42a3b99 #Master Key
export B2_ACCOUNT_KEY=00041845e8dd29d7e3d091d77bb8a631ee71332be7 #Master Application ID
RESTIC_PASSWORD='f$774$#je4%U8vp8ov*UsZMHqL$m3Smh#fEbbt7hyULQxfnnWmSiS5MEndzVWT$$n^@s$P*o4vV*^rgv3jvvrv@y35VppU$$y*vnG5V@botU&4$39Y6t9HSb3Z548M!4'


#Safety function; accepts repository to check
safety(){
	REPOSITORY="$1"
	echo -e "Checking if repository is in use - " "$REPOSITORY"
	#Check no other Restic process is using this repository; Free unnecessary locks, if present
	if [[ -n $(ps aux | grep restic | grep "$REPOSITORY") ]]; then
		echo -e "Repository is in use - ignoring"
		return 1
#		       ^ If there's a restic process holding the repository, leave it alone.
	else
		echo -e "Repository is not in use - unlocking"
		restic -q -r b2:$REPOSITORY unlock
#				^ If a lock exists but no process, the repository is safe and should be unlocked.
	fi
}

#Backup function; accepts repository and path to backup
backup(){
	REPOSITORY="$1"
	REPOSITORY_PATH="$2"
	if safety "$REPOSITORY"; then
		#Run the backup
		echo -e "Backing up repository" "$REPOSITORY"
		if restic --cache-dir="$RESTIC_CACHE_DIR" -r b2:"$REPOSITORY" backup "$REPOSITORY_PATH" --limit-upload="$BWLIMIT" --limit-download="$BWLIMIT"; then
			echo -e "$REPOSITORY_PATH" "completed upload to $REPOSITORY."
		else
			echo -e "$REPOSITORY failed to upload path" "$REPOSITORY_PATH"
		fi
	fi
}

check(){
	REPOSITORY="$1"
	PRUNE="$2"
	echo -e "Checking integrity (prune: $PRUNE) of repository" "$REPOSITORY"
##	^ This variable will have value if repo is already clean, indicating
#+	This is a post backup check.
	if [[ -n $PRUNE ]]; then
		echo -e "This repository has been cleaned already; will not clean again."
	fi
	if safety "$REPOSITORY"; then
		echo -e "Checking repository health - " "$REPOSITORY"
		if restic -r b2:"$REPOSITORY" check --limit-upload="$BWLIMIT" --limit-download="$BWLIMIT"; then
			echo -e "Repository passed integrity check - " "$REPOSITORY"
			echo -e "Current snapshots:"
			restic -r b2:"$REPOSITORY" snapshots | tee -a $LOG
		else
			echo -e "Repository failed integrity check - " "$REPOSITORY"
		fi
	fi
}

clean(){
	REPOSITORY="$1"
	if safety "$REPOSITORY"; then
		echo -e "Cleaning repository" "$REPOSITORY"
		if restic -r b2:$REPOSITORY forget --keep-daily 7 --keep-weekly 4 --keep-monthly 12 --prune --limit-upload="$BWLIMIT" --limit-download="$BWLIMIT"; then
			echo -e "Repository is trim - " "$REPOSITORY"
			echo -e "Running post clean check..."
			check "$REPOSITORY" "1"
#	 Marks repository as cleaned already ^ so it won't passed to this function again.
		else
				echo -e "Failed to prune repository" "$REPOSITORY"
		fi
	fi
}

#If cleaning was forced, or if it's the first of this month - clean.
if [[ -n $CLEAN ]] || [[ $(date +%d) == "1" ]]; then
	check Gerbil-TK
	clean Gerbil-TK
	check Pukeko-XYZ-Containers
	clean Pukeko-XYZ-Containers
	check Pukeko-XYZ-Cloud
	clean Pukeko-XYZ-Cloud

#If a specific repository was requested, back it up; otherwise, back them all up.
elif [[ -n $REPOSITORY ]] && [[ -z $CLEAN ]]; then
	case "$REPOSITORY" in
		(Gerbil-TK)
			backup Gerbil-TK /var/Red-Vol/Media/Pictures/
			;;
		(Pukeko-XYZ-Containers)
			backup Pukeko-XYZ-Containers /var/Red-Vol/Media/Containers/
			;;
		(Pukeko-XYZ-Cloud)
			backup Pukeko-XYZ-Cloud /var/Red-Vol/Media/Cloud/
			;;
		(*)
			help;;
	esac	

#If cleaning was not forced, backup the repositories	
elif [[ -z $CLEAN ]]; then
	backup Gerbil-TK /var/Red-Vol/Media/Pictures/
	backup Pukeko-XYZ-Containers /var/Red-Vol/Media/Containers/
	backup Pukeko-XYZ-Cloud /var/Red-Vol/Media/Cloud/

#If a specific repository was requested to be cleaned, clean it
elif [[ -n $REPOSITORY ]] && [[ -n $CLEAN ]]; then
	case "$REPOSITORY" in
		(Gerbil-TK)
			check Gerbil-TK
			clean Gerbil-TK
			;;
		(Pukeko-XYZ-Containers)
			check Pukeko-XYZ-Containers
			clean Pukeko-XYZ-Containers
			;;
		(Pukeko-XYZ-Cloud)
			check Pukeko-XYZ-Cloud
			clean Pukeko-XYZ-Cloud
			;;
		(*)
			help;;
	esac	
fi

#Wrap up this run's log and report nicely
echo "All done; have a nice day!"
exit 0