#!/bin/sh
. /etc/functions

bootdir=$1
add=$2
remove=$3

MENU_NAME="kexec_menu.txt"
HASH_NAME="kexec_hashes.txt"
TMP_MENU_FILE=/tmp/kexec/$MENU_NAME
TMP_HASH_FILE=/tmp/kexec/$HASH_NAME

first_menu="y"
get_menu_option() {
	num_options=`cat $TMP_MENU_FILE | wc -l`
	if [ $num_options -eq 0 ]; then
		recovery "No boot options"
	fi

	if [ $num_options -eq 1 -a $first_menu = "y" ]; then
		option_index=1
	else
		echo "+++ Select your boot option:"
		n=0
		while read option
		do
			parse_option
			n=`expr $n + 1`
			echo "$n. $name [$kernel]"
		done < $TMP_MENU_FILE

		read \
			-p "Choose the boot option [1-$n, a to abort]: " \
			option_index

		if [ "$option_index" = "a" ]; then
			recovery "Aborting boot attempt"
		fi
	fi
	first_menu="n"

	option=`head -n $option_index $TMP_MENU_FILE | tail -1`
	parse_option
}

confirm_menu_option() {
	echo "+++ Please confirm the boot details for $name:"
	echo $option

	read \
		-n 1 \
		-p "Confirm selection by pressing 'y': " \
		option_confirm
	echo
}

parse_option() {
	name=`echo $option | cut -d\| -f1`
	kernel=`echo $option | cut -d\| -f3`
}

# optionally enforce file hashes
if [ -r $TMP_HASH_FILE ]; then
	echo "+++ Checking verified boot hash file "
	# Check the hashes of all the files
	if cd $bootdir && sha256sum -c "$TMP_HASH_FILE" ; then
		echo "+++ Verified boot hashes "
	else
		recovery "$TMP_HASH_FILE: boot hash mismatch"
	fi
fi

# if no saved options, scan the boot directory and generate
if [ ! -r $TMP_MENU_FILE ]; then
	echo "+++ Scanning for unsigned boot options"
	option_file="/tmp/kexec_options.txt"
	for i in `find $bootdir -name "*.cfg"`; do
		kexec-parse-boot $i >> $option_file
	done
	if [ ! -r $option_file ]; then
		recovery "Failed to parse any boot options"
	fi
	sort $option_file | uniq > $TMP_MENU_FILE
fi

option_confirm=""
while [ "$option_confirm" != "y" ]
do
	get_menu_option
	confirm_menu_option
done

kexec-boot -b $bootdir -e "$option" -a "$add" -r "$remove"