# Copyright (C) 2013-2014  Miroslav Lichvar <mlichvar@redhat.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

export LC_ALL=C
export PATH=../../:$PATH
export CLKNETSIM_PATH=clknetsim

# Known working clknetsim revision
clknetsim_revision=7ea71b32e0caec4d8da4cecc3499b5c87098e137
clknetsim_url=https://github.com/mlichvar/clknetsim/archive/$clknetsim_revision.tar.gz

# Only Linux is supported
if [ "$(uname -s)" != Linux ]; then
	echo "Simulation tests supported only on Linux"
	exit 3
fi

# Try to download clknetsim if not found
if [ ! -e $CLKNETSIM_PATH ]; then
	curl -L "$clknetsim_url" | tar xz || exit 3
	ln -s clknetsim-$clknetsim_revision clknetsim || exit 3
fi

# Try to build clknetsim if not built
if [ ! -x $CLKNETSIM_PATH/clknetsim -o ! -e $CLKNETSIM_PATH/clknetsim.so ]; then
	make -C clknetsim || exit 3
fi

. $CLKNETSIM_PATH/clknetsim.bash

# Default test testings

default_limit=10000
default_time_offset=1e-1
default_freq_offset=1e-4
default_base_delay=1e-4
default_jitter=1e-4
default_wander=1e-9
default_refclock_jitter=""

default_update_interval=0
default_shift_pll=2

default_server_strata=1
default_servers=1
default_clients=1
default_peers=0
default_server_start=0.0
default_client_start=0.0
default_chronyc_start=1000.0
default_server_step=""
default_client_step=""

default_server_server_options=""
default_client_server_options=""
default_server_peer_options=""
default_client_peer_options=""
default_server_conf=""
default_client_conf=""
default_chronyc_conf=""
default_chronyd_options=""

default_time_max_limit=1e-3
default_freq_max_limit=5e-4
default_time_rms_limit=3e-4
default_freq_rms_limit=1e-5
default_min_sync_time=120
default_max_sync_time=210

# Initialize test settings from their defaults
for defopt in $(declare | grep '^default_'); do
	defoptname=${defopt%%=*}
	optname=${defoptname#default_}
	eval "[ -z \"\${$optname:+a}\" ] && $optname=\"\$$defoptname\""
done

test_start() {
	rm -f tmp/*
	echo "Testing $@:"
}

test_pass() {
	echo "PASS"
	exit 0
}

test_fail() {
	echo "FAIL"
	exit 1
}

test_skip() {
	echo "SKIP"
	exit 9
}

test_ok() {
	pad_line
	echo -e "\tOK"
	return 0
}

test_bad() {
	pad_line
	echo -e "\tBAD"
	return 1
}

test_error() {
	pad_line
	echo -e "\tERROR"
	return 1
}

msg_length=0
pad_line() {
	local line_length=56
	[ $msg_length -lt $line_length ] && \
		printf "%$[$line_length - $msg_length]s" ""
	msg_length=0
}

# Print aligned message
test_message() {
	local level=$1 eol=$2
	shift 2
	local msg="$*"

	while [ $level -gt 0 ]; do
		echo -n "  "
		level=$[$level - 1]
		msg_length=$[$msg_length + 2]
	done
	echo -n "$msg"

	msg_length=$[$msg_length + ${#msg}]
	if [ $eol -ne 0 ]; then
		echo
		msg_length=0
	fi
}

get_wander_expr() {
	local scaled_wander

	scaled_wander=$(awk "BEGIN {print $wander / \
		sqrt($update_interval < 0 ? 2^-($update_interval) : 1)}")

	echo "(+ $freq_offset (sum (* $scaled_wander (normal))))"
}


get_delay_expr() {
	echo "(+ $base_delay (* $jitter (exponential)))"
}

get_refclock_expr() {
	echo "(* $refclock_jitter (normal))"
}

get_chronyd_nodes() {
	echo $[$servers * $server_strata + $clients]
}

get_chronyd_conf() {
	local i stratum=$1 peer=$2

	if [ $stratum -eq 1 ]; then
		echo "local stratum 1"
		echo "$server_conf"
	elif [ $stratum -le $server_strata ]; then
		for i in $(seq 1 $servers); do
			echo "server 192.168.123.$[$servers * ($stratum - 2) + $i] $server_server_options"
		done
		for i in $(seq 1 $peers); do
			[ $i -eq $peer -o $i -gt $servers ] && continue
			echo "peer 192.168.123.$[$servers * ($stratum - 1) + $i] $server_peer_options"
		done
		echo "$server_conf"
	else
		for i in $(seq 1 $servers); do
			echo "server 192.168.123.$[$servers * ($stratum - 2) + $i] $client_server_options"
		done
		for i in $(seq 1 $peers); do
			[ $i -eq $peer -o $i -gt $clients ] && continue
			echo "peer 192.168.123.$[$servers * ($stratum - 1) + $i] $client_peer_options"
		done
		echo "$client_conf"
	fi
}

# Check if the clock was well synchronized
check_sync() {
	local i sync_time max_time_error max_freq_error ret=0
	local rms_time_error rms_freq_error

	test_message 2 1 "checking clock sync time, max/rms time/freq error:"

	for i in $(seq 1 $(get_chronyd_nodes)); do
		[ $i -gt $[$servers * $server_strata] ] || continue

		sync_time=$(find_sync tmp/log.offset tmp/log.freq $i \
			$time_max_limit $freq_max_limit 1.0)
		max_time_error=$(get_stat 'Maximum absolute offset' $i)
		max_freq_error=$(get_stat 'Maximum absolute frequency' $i)
		rms_time_error=$(get_stat 'RMS offset' $i)
		rms_freq_error=$(get_stat 'RMS frequency' $i)

		test_message 3 0 "node $i: $sync_time $(printf '%.2e %.2e %.2e %.2e' \
			$max_time_error $max_freq_error $rms_time_error $rms_freq_error)"

		check_stat $sync_time $min_sync_time $max_sync_time && \
			check_stat $max_time_error 0.0 $time_max_limit && \
			check_stat $max_freq_error 0.0 $freq_max_limit && \
			check_stat $rms_time_error 0.0 $time_rms_limit && \
			check_stat $rms_freq_error 0.0 $freq_rms_limit && \
			test_ok || test_bad

		[ $? -eq 0 ] || ret=1
	done

	return $ret
}

# Check if chronyd exited properly
check_chronyd_exit() {
	local i ret=0

	test_message 2 1 "checking chronyd exit:"

	for i in $(seq 1 $(get_chronyd_nodes)); do
		test_message 3 0 "node $i:"

		tail -n 1 tmp/log.$i | grep -q 'chronyd exiting' && \
			test_ok || test_bad
		[ $? -eq 0 ] || ret=1
	done

	return $ret
}

# Check for problems in source selection
check_source_selection() {
	local i ret=0

	test_message 2 1 "checking source selection:"

	for i in $(seq $[$servers * $server_strata + 1] $(get_chronyd_nodes)); do
		test_message 3 0 "node $i:"

		! grep -q 'no majority\|no reachable sources' tmp/log.$i && \
			grep -q 'Selected source' tmp/log.$i && \
			test_ok || test_bad
		[ $? -eq 0 ] || ret=1
	done

	return $ret
}

# Check if incoming and outgoing packet intervals are sane
check_packet_interval() {
	local i ret=0 mean_in_interval mean_out_interval min_in_interval min_out_interval

	test_message 2 1 "checking mean/min incoming/outgoing packet interval:"

	for i in $(seq 1 $(get_chronyd_nodes)); do
		mean_in_interval=$(get_stat 'Mean incoming packet interval' $i)
		mean_out_interval=$(get_stat 'Mean outgoing packet interval' $i)
		min_in_interval=$(get_stat 'Minimum incoming packet interval' $i)
		min_out_interval=$(get_stat 'Minimum outgoing packet interval' $i)

		test_message 3 0 "node $i: $(printf '%.2e %.2e %.2e %.2e' \
			$mean_in_interval $mean_out_interval $min_in_interval $min_out_interval)"

		# Check that the mean intervals are non-zero and shorter than
		# limit, incoming is not longer than outgoing for stratum 1
		# servers, outgoing is not longer than incoming for clients,
		# and the minimum outgoing interval is not shorter than the NTP
		# sampling separation or iburst interval for clients
		nodes=$[$servers * $server_strata + $clients]
		check_stat $mean_in_interval 0.1 inf && \
			check_stat $mean_out_interval 0.1 inf && \
			([ $i -gt $servers ] || \
				check_stat $mean_in_interval 0.0 $mean_out_interval 10*$jitter) && \
			([ $i -le $[$servers * $server_strata] ] || \
				check_stat $mean_out_interval 0.0 $mean_in_interval 10*$jitter) && \
			([ $i -le $[$servers * $server_strata] ] || \
				check_stat $min_out_interval \
					$([ $servers -gt 1 ] && echo 0.18 || echo 1.8) inf) && \
			test_ok || test_bad

		[ $? -eq 0 ] || ret=1
	done

	return $ret
}

# Compare chronyc output with specified pattern
check_chronyc_output() {
	local i ret=0 pattern=$1

	test_message 2 1 "checking chronyc output:"

	for i in $(seq $[$(get_chronyd_nodes) + 1] $[$(get_chronyd_nodes) + $clients]); do
		test_message 3 0 "node $i:"

		[[ "$(cat tmp/log.$i)" =~ $pattern ]] && \
			test_ok || test_bad
		[ $? -eq 0 ] || ret=1
	done

	return $ret
}

# Check if only NTP port (123) was used
check_packet_port() {
	local i ret=0 port=123

	test_message 2 1 "checking port numbers in packet log:"

	for i in $(seq 1 $(get_chronyd_nodes)); do
		test_message 3 0 "node $i:"

		grep -E -q "	$port	[0-9]+\$" tmp/log.packets && \
			! grep -E "^[0-9e.+-]+	$i	" tmp/log.packets | \
			grep -E -q -v "	$port	[0-9]+\$" && \
			test_ok || test_bad
		[ $? -eq 0 ] || ret=1
	done

	return $ret
}

# Print test settings which differ from default value
print_nondefaults() {
	local defopt defoptname optname

	test_message 2 1 "non-default settings:"
	declare | grep '^default_*' | while read defopt; do
		defoptname=${defopt%%=*}
		optname=${defoptname#default_}
		eval "[ \"\$$optname\" = \"\$$defoptname\" ]" || \
			test_message 3 1 $(eval "echo $optname=\$$optname")
	done
}

run_simulation() {
	local nodes=$1

	test_message 2 0 "running simulation:"

	start_server $nodes \
		-o tmp/log.offset -f tmp/log.freq -p tmp/log.packets \
		-R $(awk "BEGIN {print $update_interval < 0 ? 2^-($update_interval) : 1}") \
		-r $(awk "BEGIN {print $max_sync_time * 2^$update_interval}") \
		-l $(awk "BEGIN {print $limit * 2^$update_interval}") && test_ok || test_error
}

run_test() {
	local i j n stratum node nodes step start freq offset conf

	test_message 1 1 "network with $servers*$server_strata servers and $clients clients:"
	print_nondefaults

	nodes=$(get_chronyd_nodes)
	[ -n "$chronyc_conf" ] && nodes=$[$nodes + $clients]

	for i in $(seq 1 $nodes); do
		echo "node${i}_shift_pll = $shift_pll"
		for j in $(seq 1 $nodes); do
			[ $i -eq $j ] && continue
			echo "node${i}_delay${j} = $(get_delay_expr)"
			echo "node${j}_delay${i} = $(get_delay_expr)"
		done
	done > tmp/conf

	node=1

	for stratum in $(seq 1 $[$server_strata + 1]); do
		[ $stratum -le $server_strata ] && n=$servers || n=$clients

		for i in $(seq 1 $n); do
			test_message 2 0 "starting node $node:"
			if [ $stratum -eq 1 ]; then
				step=$server_step
				start=$server_start
				freq=""
				offset=0.0
			elif [ $stratum -le $server_strata ]; then
				step=$server_step
				start=$server_start
				freq=$(get_wander_expr)
				offset=0.0
			else
				step=$client_step
				start=$client_start
				freq=$(get_wander_expr)
				offset=$time_offset
			fi

			conf=$(get_chronyd_conf $stratum $i $n)

			[ -z "$freq" ] || echo "node${node}_freq = $freq" >> tmp/conf
			[ -z "$step" ] || echo "node${node}_step = $step" >> tmp/conf
			[ -z "$refclock_jitter" ] || \
				echo "node${node}_refclock = $(get_refclock_expr)" >> tmp/conf
			echo "node${node}_offset = $offset" >> tmp/conf
			echo "node${node}_start = $start" >> tmp/conf
			start_client $node chronyd "$conf" "" "$chronyd_options" && \
				test_ok || test_error

			[ $? -ne 0 ] && return 1
			node=$[$node + 1]
		done
	done

	for i in $(seq 1 $[$nodes - $node + 1]); do
		test_message 2 0 "starting node $node:"

		echo "node${node}_start = $chronyc_start" >> tmp/conf
		start_client $node chronyc "$chronyc_conf" "" \
			"-n -h 192.168.123.$[$node - $clients]" && \
			test_ok || test_error

		[ $? -ne 0 ] && return 1
		node=$[$node + 1]
	done

	run_simulation $nodes
}