#!/bin/sh

set -e

SNAP_ID=$1
SNAP_MOUNTPOINT="$2"

CDIR=`dirname $0`

if ! test -e $SNAP_MOUNTPOINT
then
        echo "Snapshot at $SNAP_MOUNTPOINT was already removed"
        exit 0
fi

TYPE=$(df -T -P | egrep " ${SNAP_MOUNTPOINT}\$" | head -n 1 | tr -s " " | cut -d" " -f2)

if [ "x$TYPE" = "x" ]
then
        if btrfs subvolume list -o "$SNAP_MOUNTPOINT" > /dev/null 2>&1
        then
                TYPE="btrfs"
        fi
fi

if [ "x$TYPE" = "xbtrfs" ]
then
    $CDIR/btrfs_remove_filesystem_snapshot "$@"
    exit $?
fi

if ! df -T -P | egrep "${SNAP_MOUNTPOINT}\$" > /dev/null 2>&1
then
	echo "Snapshot is not mounted. Already removed"
	rmdir "${SNAP_MOUNTPOINT}"
	VOLNAME=`ls /dev/mapper/* | grep "urbackup_snap_${SNAP_ID}" | grep -v "\-cow"`
	if [ -e "$VOLNAME" ]
	then
		echo "LVM snapshot still exists. Destroying LVM snapshot $VOLNAME..."
		export LVM_SUPPRESS_FD_WARNINGS=1
		lvremove -f "$VOLNAME"
	fi
	
	exit 0
fi

if lsblk -r --output "NAME,MOUNTPOINT" --paths > /dev/null 2>&1
then
	VOLNAME=`lsblk -r --output "NAME,MOUNTPOINT" --paths | egrep " ${SNAP_MOUNTPOINT}\$" | head -n 1 | tr -s " " | cut -d" " -f1`
else
	VOLNAME=`lsblk -r --output "NAME,MOUNTPOINT" | egrep " ${SNAP_MOUNTPOINT}\$" | head -n 1 | tr -s " " | cut -d" " -f1`
	VOLNAME="/dev/mapper/$VOLNAME"
fi

if [ "x$VOLNAME" = x ]
then
    echo "Could not find LVM volume for mountpoint ${SNAP_MOUNTPOINT}"
    exit 1
fi

if [ ! -e "$VOLNAME" ]
then
	echo "LVM volume for mountpoint ${SNAP_MOUNTPOINT} does not exist"
    exit 1
fi

echo "Unmounting $VOLNAME at /mnt/urbackup_snaps/$SNAP_ID..."

if ! umount /mnt/urbackup_snaps/$SNAP_ID
then
		lsof | grep /mnt/urbackup_snaps/$SNAP_ID || true
        sleep 10
        umount /mnt/urbackup_snaps/$SNAP_ID
fi

rmdir "${SNAP_MOUNTPOINT}"

echo "Destroying LVM snapshot $VOLNAME..."

export LVM_SUPPRESS_FD_WARNINGS=1

lvremove -f "$VOLNAME"