#!/bin/sh
# Copyright 2018 Didier Spaier <didier~at~slint~dot~fr>
#
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
#  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
#  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
#  OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
#  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
#  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
#  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

# Updated on Thu, 12 Jul 2018 23:55:35 +0200


one_space() {
	echo "$1"|sed "s/ \{1,\}/ /g"
}

to_lower() {
echo "$1"|tr '[:upper:]' '[:lower:]'
}

set_mountpoint() {
	ESP_NAME=$(one_space "$(lsblk -l -o uuid,name)"|grep $UUID|cut -d" " -f 2)
	MOUNTPOINT=$(one_space "$(df -h)"|grep /dev/$ESP_NAME|cut -d" " -f 6)
	ESP=/dev/$ESP_NAME
	MOUNTED=y
	if [ "$MOUNTPOINT" = "" ]; then
		MOUNTPOINT=$MNT
		mount $ESP $MNT
		MOUNTED=n
	fi 
}

remove_previous_files() {
	# Very old versioin without /var/efibootmenuinstall
	if [ -d /boot/efi/EFI/efibootmenu ]; then
		rm -rf /boot/efi/EFI/efibootmenu
	fi
	if [ ! -f /var/efibootmenuinstall ]; then
		return
	fi
	while read UUID EFIPATH; do
		set_mountpoint
		EFIDIR=$(dirname $EFIPATH)
		if [ ! -d $MOUNTPOINT$EFIDIR ]; then
			# Don't try to cd to a directory that have been removed
			# after previous installation in system ESP
			continue
		fi
		( cd $MOUNTPOINT$EFIDIR
		if [ -f efibootmenu.md5 ]; then
			if md5sum -c --quiet efibootmenu.md5; then
				rm BOOTx64.EFI
				rm efibootmenu.md5
			fi
		fi
		if [ -f efibootgrub.md5 ]; then
			if md5sum -c --quiet efibootgrub.md5; then
				rm grub.cfg
				rm efibootgrub.md5
			fi
		fi
		)
		if [ "$(ls -A $MOUNTPOINT$EFIDIR)" = "" ]; then
			rmdir $MOUNTPOINT$EFIDIR
		fi
		if [ "$MOUNTED" = "n" ]; then
			umount $MNT
		fi
	done < /var/efibootmenuinstall
	rm -f /boot/efimultibootmenux64.efi
	rm /var/efibootmenuinstall
	rm -f /var/efibootmenu
	rm -rf /etc/efibootmenu
}

display_install_path() {
	if [ "$1" = "main" ]; then
		SHOW=$(grep efibootmenu /var/efibootmenuinstall)
	else
		SHOW=$(grep /EFI/BOOT /var/efibootmenuinstall)
	fi
	UUID=$(echo $SHOW|cut -d" " -f1)
	ESP_PATH=$(echo $SHOW|cut -d" " -f2)
	PARTITION=$(one_space "$(lsblk -l -o UUID,NAME)"|grep $UUID|cut -d" " -f2)
	echo "/dev/$PARTITION as ${ESP_PATH}.
"
}

list_the_ESP() {
	# List the accessible EFI system partitions or ESPs
	lsblk -l -o name,parttype,uuid,pkname|\
	grep -i -F -e "$ESPPARTTYPE" -e "$OSTYPE"|sed "s/ \{1,\}/ /g" > $ESPLIST
	if [ ! -s $ESPLIST ]; then # No EFI partitions
		echo "No EFI partition found, game over."
		return
	fi
	
}

house_cleaning() {
	clear
	echo "Please wait..."
	list_the_ESP
	# Output one line per ESP with these fields:
	# name parttype uuid pkname
	# pkname is the name of the device (parent of the partition)
	remove_previous_files
}

the_end() {
	rm -f $ESPLIST
	rmdir $MNT
	rmdir $TMP
	clear
	echo "
All done.
You may now want to run EFI3M."
}

if [ $(id -u) -ne 0 ]; then
	echo "Only root may run this script."
	exit
fi
if [ ! -d /sys/firmware/efi ]; then
	echo "EFI booting is not enabled, game over."
	exit
fi
if [ ! -f /var/efibootmenuinstall ] && [ ! -d /boot/efi/EFI/efibootmenu ]; then
	echo "No old version found".
	exit
fi
echo "This script will remove all files installed by an old version of EFI3M."
read -p "Ready to proceed [y/N]? " dummy
if [ ! "$(to_lower $dummy)" = "y" ]; then
	echo "Nothing done."
	exit
fi
remove_previous_files
the_end