#!/bin/bash
PS4="\e[34m> ${0##*/}:\e[0m "
set -x
set -e
trap cleanup EXIT

if (( $# < 1 )); then
    echo Usage: ${0##*/} link-index peer-p2p-mac
    echo        eg. sudo ${0##*/} 3 ac:a2:13:6e:f8:2f
    exit 1
fi

if [[ ${#2} != 17 ]]; then
    echo Invalid peer-p2p-mac: $2
    exit 1
fi

# since this wfd subelement is used for device info, so no wfd subelemnt
# id needed (eg. 000600101b4400c8 vs 00000600101b4400c8)
wfd_subelems=000600101c4400c8
link_index="_3${1:0:1}${1:1}"
peer_id="${2//:/_3a}_40$1"

# $1: service
# $2: object
# $3: interface
# $4: member
# $5: property value
wait_prop_change()
{
    for ((i=0; i<60; i++)); do
        read -a cols < <(busctl get-property "${@:1:4}")
        case ${cols[0]} in
            s | o) cols[1]="${cols[1]:1:${#cols[1]}-2}" ;;
        esac
        if [[ "$5" == "${cols[1]}" ]]; then
            return 0
        fi
        sleep 1
    done

    echo !!!timeout!!!
    return 1
}

# $1: service
# $2: object
# $3: interface
# $4: member
wait_object()
{
    while ! busctl get-property "$1" "$2" "$3" "$4" &>/dev/null; do
        sleep 1
    done
}

# $1: service
# $2: object
# $3: interface
# $4: property
# $5: expected property value
# $6: method
# $...: arguments
invoke()
{
    set +x
    wait_object "${@:1:4}"
    busctl call "${@:1:3}" "${@:6}"
    wait_prop_change "${@:1:5}"
    set -x
}

# $1: service
# $2: object
# $3: interface
# $4: member
# $5: property spec
# $6: property values
set_prop()
{
    set +x
    busctl set-property "$@"
    wait_prop_change "${@:1:4}" "${@:6:1}"
    set -x
}

# $1: service
# $2: object
# $3: interface
# $4: member
# $5: variable name
get_prop()
{
    read -a l < <(busctl get-property "${@:1:4}")
    eval $5=\"${l[1]}\"
}

cleanup()
{
    kill 0
    set -x
    for (( i=${#cleanup[@]}-1; i>=0; --i )); do
        eval ${cleanup[$i]} || true
    done
}

cleanup_push()
{
    cleanup+=("$*")
}

link_unmanage()
{
    set_prop org.freedesktop.miracle.wifi \
        /org/freedesktop/miracle/wifi/link/$link_index \
        org.freedesktop.miracle.wifi.Link \
        Managed b false
}

link_stop_p2pscan()
{
    set_prop org.freedesktop.miracle.wifi \
        /org/freedesktop/miracle/wifi/link/$link_index \
        org.freedesktop.miracle.wifi.Link \
        P2PScanning b false
}

peer_disconnect()
{
    invoke org.freedesktop.miracle.wifi \
        /org/freedesktop/miracle/wifi/peer/$peer_id \
        org.freedesktop.miracle.wifi.Peer \
        Connected false \
        Disconnect
}

killall miracle-wifid &>/dev/null || true
killall miracle-wfwctl &>/dev/null || true

set_prop org.freedesktop.NetworkManager \
    /org/freedesktop/NetworkManager/Devices/$1 \
    org.freedesktop.NetworkManager.Device \
    Managed b false
set_prop org.freedesktop.miracle.wifi \
    /org/freedesktop/miracle/wifi/link/$link_index \
    org.freedesktop.miracle.wifi.Link \
    Managed b true
cleanup_push link_unmanage
set_prop org.freedesktop.miracle.wifi \
    /org/freedesktop/miracle/wifi/link/$link_index \
    org.freedesktop.miracle.wifi.Link \
    WfdSubelements s "$wfd_subelems"
# this one is tricky, we wait for wpa_supplicant fully started then start 
# P2P scaning, or "Invalid argument" will return
sleep 0.5
echo wait for peer...
set_prop org.freedesktop.miracle.wifi \
    /org/freedesktop/miracle/wifi/link/$link_index \
    org.freedesktop.miracle.wifi.Link \
    P2PScanning b true
cleanup_push link_stop_p2pscan
echo connect to peer...
invoke org.freedesktop.miracle.wifi \
    /org/freedesktop/miracle/wifi/peer/$peer_id \
    org.freedesktop.miracle.wifi.Peer \
    Connected true \
    Connect ss auto ''
cleanup_push peer_disconnect
get_prop org.freedesktop.miracle.wifi \
    /org/freedesktop/miracle/wifi/peer/$peer_id \
    org.freedesktop.miracle.wifi.Peer \
    Interface p2p_iface
tcpdump -nnvvXS -s 0 -i $p2p_iface port 7236 or port 67 or port 68 &
while ! killall -0 miracle-wfdctl && [[ -z "$nocheck" ]] &>/dev/null; do
    echo please run miracle-wfdctl manually
    sleep 3
done
echo starting WFD session...
invoke org.freedesktop.miracle.wfd \
    /org/freedesktop/miracle/wfd/sink/$peer_id \
    org.freedesktop.miracle.wfd.Sink \
    Peer /org/freedesktop/miracle/wifi/peer/$peer_id \
    StartSession

wait