#!/bin/bash

# Script for LVM-resize. Version 0.1
# Usage: ./resize.sh LV-Partition-name Size(GB) VolumeGroupName LOG_FILE_NAME

if [ -z "${1}" ]; then
	LV_NAME="tmp"
else
	LV_NAME="${1}"
fi

if [ -z "${2}" ]; then
	SIZE="2"
else
	SIZE="${2}"
fi

if [ -z "${3}" ]; then
	VG_NAME="system"
else
	VG_NAME="${3}"
fi

if [ -z "${4}" ]; then
	LOG_FILE="~/log-resize.log"
else
	LOG_FILE="${4}"
fi
echo "We would extend ${VG_NAME}-${LV_NAME} for ${SIZE} GiB."
echo "Note: If you have any problem - check ${LOG_FILE}"
echo "[y/n]"
read AGREE
if [ "${AGREE}" = "y" ]; then
    vgscan 
    echo "Umounting ${VG_NAME}-${LV_NAME}" > ${LOG_FILE}
    umount /dev/mapper/${VG_NAME}-${LV_NAME} >> ${LOG_FILE} 2>&1 || echo "[Failed]: Cannot umount ${VG_NAME}-${LV_NAME}"
    echo >> ${LOG_FILE}
    echo "Resizing LV-partition" >> ${LOG_FILE}
    lvresize -L +${SIZE}G -v /dev//${VG_NAME}/${LV_NAME} >> ${LOG_FILE} 2>&1 || echo "[Failed]: Cannot resize ${VG_NAME}-${LV_NAME}"
    echo >> ${LOG_FILE}
    echo "Turning off journal" >> ${LOG_FILE}
    tune2fs -O ^has_journal /dev/${VG_NAME}/${LV_NAME} >> ${LOG_FILE} 2>&1 || echo "[Failed]: Cannot turn off journal"
    echo >> ${LOG_FILE}
    echo "Checking filesystem:" >> ${LOG_FILE}
    e2fsck -f /dev/mapper/${VG_NAME}-${LV_NAME}
    echo >> ${LOG_FILE}
    echo "Resizing fs" >> ${LOG_FILE}
    resize2fs -p /dev/${VG_NAME}/${LV_NAME} >> ${LOG_FILE} 2>&1 || echo "[Failed]: resize2fs failed"
    echo >> ${LOG_FILE}
    echo "Turning on journal" >> ${LOG_FILE}
    tune2fs -O has_journal /dev/${VG_NAME}/${LV_NAME}  >> ${LOG_FILE} 2>&1 || echo "[Failed]: Cannot turn on journal"
    echo >> ${LOG_FILE}
    echo "Mounting fs back" >> ${LOG_FILE}
    mount /dev/mapper/${VG_NAME}-${LV_NAME} >> ${LOG_FILE} 2>&1 || echo "[Failed]: Cannot mount ${VG_NAME}-${LV_NAME}"
else
    echo "canceled"
fi