#!/bin/sh
. /usr/share/os-prober/common.sh
set -e

# add support for btrfs with no separate /boot
# that is, rootsv = bootsv
partition="$1"
bootpart="$2"
mpoint="$3"
type="$4"
rootsv="$5"
bootsv="$6"

found_item=0

entry_result () {
	if [ "x$type" = "xbtrfs" -a "$rootsv" = "$bootsv" ]; then
		# trim off the leading subvol
		kernelfile=$(echo "$kernel" | cut -d '/' -f 2- | cut -d '/' -f 2-)
	else
		kernelfile=$kernel
	fi
	if [ "$ignore_item" = 0 ] && \
	   [ -n "$kernel" ] && \
	   [ -e "$mpoint/$kernelfile" ]; then
		result "$rootpart:$bootpart:$title:$kernel:$initrd:$parameters"
		found_item=1
	fi
	kernel=""
	parameters=""
	initrd=""
	title=""
	ignore_item=0
}

parse_grub_menu () {
	mpoint="$1"
	rootpart="$2"
	bootpart="$3"
	
	kernel=""
	parameters=""
	initrd=""
	title=""
	ignore_item=0

	while read line; do
		debug "parsing: $line"
		set -f
		set -- $line
		set +f
		case "$1" in
			menuentry)
				entry_result
				shift 1
				# The double-quoted string is the title.
				# Make sure to look at the text of the line
				# before 'set' mangled it.
				title="$(echo "$line" | sed -n 's/[^"]*"\(.*\)".*/\1/p' | sed 's/://g')"
				if [ -z "$title" ]; then
					# ... or single-quoted?  Be careful
					# to handle constructions like
					# 'foo'\''bar' (which expands to
					# foo'bar, as in shell), and to
					# handle multiple single-quoted
					# strings on the same line.
					title="$(echo "$line" | sed -n "s/[^']*'\(\([^']\|'\\\\''\)*\)'.*/\1/p" | sed "s/'\\\\''/'/; s/://g")"
				fi
				if [ -z "$title" ]; then
					ignore_item=1
				elif echo "$title" | grep -q '(on /dev/[^)]*)$'; then
					log "Skipping entry '$title':"
					log "appears to be an automatic reference taken from another menu.lst"
					ignore_item=1
				fi
			;;
			linux)
				# Hack alert: sed off any (hdn,n) but
				# assume the kernel is on the same
				# partition.
				kernel="$(echo "$2" | sed 's/(.*)//')"
				shift 2
				parameters="$@"
				# Systems with a separate /boot will not have
				# the path to the kernel in grub.cfg.
				if [ "$partition" != "$bootpart" ]; then
					kernel="/boot$kernel"
				fi
			;;
			initrd)
				initrd="$(echo "$2" | sed 's/(.*)//')"
				# Initrd same.
				if [ "$partition" != "$bootpart" ]; then
					initrd="/boot$initrd"
				fi
			;;
			"}")
				entry_result
			;;
		esac
	done

	entry_result
}

if [ -e "$mpoint/boot/grub/grub.cfg" ] && \
   ([ ! -e "$mpoint/boot/grub/menu.lst" ] || \
    [ "$mpoint/boot/grub/grub.cfg" -nt "$mpoint/boot/grub/menu.lst" ]); then
	debug "parsing grub.cfg"
	parse_grub_menu "$mpoint" "$partition" "$bootpart" < "$mpoint/boot/grub/grub.cfg"
elif [ -e "$mpoint/boot/grub2/grub.cfg" ]; then
	debug "parsing grub.cfg"
	parse_grub_menu "$mpoint" "$partition" "$bootpart" < "$mpoint/boot/grub2/grub.cfg"
fi

if [ "$found_item" = 0 ]; then
	exit 1
else
	exit 0
fi