#!/bin/bash

goodbye()
{
	:
	rm -rf $tmp_files
}

usage()
{
cat << EOT >&2

 $myname -h
 $myname {net|<image-file>} [-b hostname]

EOT
	[ "$1" ] && exit $1
	exit 0
}

log()
{
	echo "$log_delim $*"
	/usr/bin/logger -t "$myname" "$*"
}

err()
{
	echo "$log_delim $*" >&2
	/usr/bin/logger -t "$myname" "$*"
}

fatal()
{
	err "Fatal: $@ ... giving up"
	exit 1
}

do_sudo()
{
	if [ "$UID" = 0 ]; then
		while [[ $1 =~ ^- ]]; do shift; done
		log running $@
		eval "$@"
		return $?
	fi
	log running sudo $@
	#sudo -p "Password for $myname:" $@
	eval sudo "$@"
	return $?
}

ldap_search()
{
	local ldap_server=ldap.lcl
	local binddn=cn=ldapadm,dc=jannet,dc=de
	local password_files="$HOME/.feedfs-ldap/passwords/$binddn@$ldap_server $HOME/.ldap.secret"
	local p password_file
	for p in $password_files; do
		[ -r "$p" ] || continue
		password_file=$p
		break
	done
	[ "$password_file" ] || fatal "None of the LDAP password files $password_files exists"
	ldapsearch -y $password_file -xZ -h $ldap_server -D $binddn -b $base,ou=networks,dc=jannet,dc=de $@
}

list_hostnames()
{
	ldap_search -LLL "(objectClass=dhcpHost)" cn | sed '/cn: / !d; s/cn: //'
}

boot_net()
{
	local mac
	[ "$hostname" ] && {
		#set -x
		mac=`ldap_search -LLL "(cn=$short_hostname) dhcpHWAddress" | 
			sed '/dhcpHWAddress:/ !d; s/dhcpHWAddress: ethernet *//'`
		macaddr=",macaddr=$mac"
	}

	systemctl try-start dhcpd-priv.lcl
	systemctl try-start nfsserver

	[ "$nic_model" ] || nic_model=",model=e1000"
	# need this for net access, would be nicer if it didn't run as root
	# -nographic

	do_sudo -E /usr/bin/$qemu_exe  \
		-boot n  \
		-net tap,ifname=tap0,script=$tmpdir/qemu-ifup,downscript=$tmpdir/qemu-ifdown \
		-net nic$nic_model$macaddr \
		"$qemu_opts"

	# invalid param macaddr
#	do_sudo -E /usr/bin/$qemu_exe  \
#		-boot n  \
#		-net bridge,br=$bridge,$nic_model,macaddr=$macaddr \
#		$qemu_opts

	# access denied by ACL files
#	do_sudo -E /usr/bin/$qemu_exe  \
#		-boot n  \
#		-net bridge,br=$bridge,$nic_model \
#		$qemu_opts
}

boot_image()
{
	local boot_image="$1"

	test -r "$boot_image" || fatal "inaccessible boot image \"$boot_image\""
		#-net bridge,br=$bridge \
		#-net nic,vlan=1$nic_model,macaddr=00:02:36:22:13:6c \
 		#-net tap,ifname=tap1,vlan=1,script=$tmpdir/qemu-ifup,downscript=$tmpdir/qemu-ifdown \
	#set -x
	do_sudo -E /usr/bin/$qemu_exe  \
		-net nic,$nic_model$macaddr \
 		-net tap,ifname=tap0,vlan=0,script=$tmpdir/qemu-ifup,downscript=$tmpdir/qemu-ifdown \
		"$qemu_opts" \
		-drive file=$boot_image
}

boot()
{
	tmpdir=`mktemp -d /tmp/$myname-XXXXXX`
	ln -s $exe $tmpdir/qemu-ifup
	ln -s $exe $tmpdir/qemu-ifdown

	#do_sudo /sbin/modprobe kvm-intel
	tmp_files="$tmp_files $tmpdir"
	xhost +

	case $1 in
	net)
		shift
		boot_net "$@"
		;;
	*)
		boot_image "$@"
		;;
	esac
}

# -- here we go

myname=`basename $0`
log_delim="==========================="
log running $0 $@
[ -x $0 ] || chmod u+x $0 || fatal "$0 is not executable"
exe=`readlink -f $0`
dirname=`dirname $exe`
bridge=priv0
#bridge=in1
macaddr=,macaddr=00:0B:DC:9B:D6:DA
base=dc=priv,dc=lcl
qemu_exe=qemu-kvm
qemu_opts=""
ip=`PATH=/usr/sbin:/sbin:/usr/bin /usr/bin/which ip`
#nic_model=",model=rtl8139"
tmp_files=""
tmpdir=""

trap goodbye INT QUIT EXIT KILL TERM PIPE

OPTIND=1
while getopts lhb:o:x:n:B:M: flag; do
	case $flag in
	h)
		usage 0;;
	l)
		list_hostnames
		exit 0;;
	b)
		hostname="$OPTARG"
		short_hostname=`echo $hostname | sed 's/\..*//'`
		dns_domain=`echo $hostname | cut -d. -f2-`
		base=`echo $dns_domain | sed 's/\./,/g; s/\(^\|,\)/\1dc=/g'`
		;;
	x)
		qemu_exe="$OPTARG";;
	o)
		qemu_opts="$OPTARG";;
	n)
		nic_model=",model=$OPTARG";;
	B)
		bridge=$OPTARG;;
	M)
		macaddr=",macaddr=$OPTARG";;

	*)
		usage 1;;
	esac
done
shift $(($OPTIND - 1))

case $myname in
*ifup*)
	virt_if=$1
	touch /tmp/i-ran-$myname
	do_sudo $ip link set $virt_if up
	do_sudo $ip link set dev $virt_if master $bridge
	;;

*ifdown*)
	virt_if=$1
	do_sudo $ip link set dev $virt_if nomaster
	do_sudo $ip link set dev $virt_if down
	;;
qemu.sh)
	boot "$@"
	;;
qemu-boot.sh) # legacy
	boot "$@"
	;;
*)
	echo called as unknown executable name $0
	;;
esac