#!/bin/bash
#
#  Copyright (c) 2022, The OpenThread Authors.
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#  modification, are permitted provided that the following conditions are met:
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#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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#  POSSIBILITY OF SUCH DAMAGE.

set -euxo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
readonly SCRIPT_DIR

ABS_TOP_BUILDDIR="$(cd "${top_builddir:-"${SCRIPT_DIR}"/../../}" && pwd)"
readonly ABS_TOP_BUILDDIR

OTBR_AGENT="${ABS_TOP_BUILDDIR}/src/agent/otbr-agent"
readonly OTBR_AGENT

OT_RCP=$(command -v ot-rcp)
readonly OT_RCP

at_exit()
{
    EXIT_CODE=$?

    sudo killall otbr-agent || true

    sudo ip link del ilstest0 || true
    sudo ip link del ilstest1 || true
    sudo ip link del ilstest2 || true

    exit $EXIT_CODE
}

trap at_exit INT TERM EXIT

sudo cp "${ABS_TOP_BUILDDIR}/src/agent/otbr-agent.conf" /etc/dbus-1/system.d/
sudo chmod +r /etc/dbus-1/system.d/otbr-agent.conf
sudo systemctl reload dbus

sudo modprobe dummy

prepare_infra_link()
{
    local netif="$1"
    local mac="$2"

    sudo ip link add "${netif}" type dummy
    sudo ifconfig "${netif}" hw ether "${mac}"
    sudo ifconfig "${netif}" up
}

sudo ip link del ilstest0 || true
sudo ip link del ilstest1 || true
sudo ip link del ilstest2 || true

prepare_infra_link "ilstest0" "C8:D7:4A:4E:47:00"
prepare_infra_link "ilstest1" "C8:D7:4A:4E:47:01"
prepare_infra_link "ilstest2" "C8:D7:4A:4E:47:02"

sleep 10
ifconfig
ip link list

sudo "${OTBR_AGENT}" -I wpan0 -v -d7 -B ilstest0 -B ilstest1 -B ilstest2 "spinel+hdlc+forkpty://${OT_RCP}?forkpty-arg=1" 2>&1 | tee output &

function check_infra_link()
{
    grep "\-ILS\-\-\-\-\-: Infra link \(selected\|unchanged\|switched\)" output | tail -1
}

function verify_otbr_agent_exited()
{
    if pgrep otbr-agent; then
        return 1
    fi
}

sleep 3
# Verify ILS selects ilstest0
check_infra_link | grep "selected: ilstest0"

sudo ifconfig ilstest1 down
sudo ifconfig ilstest2 down

sleep 3
# Verify ILS keeps using ilstest0
check_infra_link | grep "unchanged: ilstest0"

sudo ifconfig ilstest2 up

sleep 3
# Verify ILS keeps using ilstest0 because ilstest0 is still RUNNING
check_infra_link | grep "unchanged: ilstest0"

sudo ifconfig ilstest0 down
sleep 3
# Verify ILS keeps using ilstest0 because ilstest0 was RUNNING recently
check_infra_link | grep "unchanged: ilstest0"

sudo ifconfig ilstest0 up
sleep 11

# Verify ILS keeps using ilstest0 because ilstest0 is RUNNING again
check_infra_link | grep "unchanged: ilstest0"

sudo ifconfig ilstest0 down
sleep 11
# Verify ILS switches to ilstest2 after ilstest0 is DOWN for more than 10s
check_infra_link | grep "switched from ilstest0 to ilstest2"
verify_otbr_agent_exited

# Now, only ilstest2 is RUNNING

sudo "${OTBR_AGENT}" -I wpan0 -v -d7 -B ilstest0 -B ilstest1 -B ilstest2 "spinel+hdlc+forkpty://${OT_RCP}?forkpty-arg=1" 2>&1 | tee output &

sleep 3
# Verify ILS selects ilstest2 after reboot
check_infra_link | grep "selected: ilstest2"

sudo ifconfig ilstest2 down
sleep 3
# Verify ILS keeps using ilstest2 because ilstest2 was RUNNING recently
check_infra_link | grep "unchanged: ilstest2"

sleep 8
sudo ifconfig ilstest1 up
sleep 3
# Verify ILS switches to ilstest1 because ilstest2 was not RUNNING for more than 10s
check_infra_link | grep "switched from ilstest2 to ilstest1"
verify_otbr_agent_exited