###
# Not Yet Implemented: just draw a warnig box during 3 seconds
var nyi = func (x) { gui.popupTip(x ~ ': not yet implemented', 3) }

###
# print message in terminal
var msg = func (str) { print('ZKV1000 >> ', str) }

###
# print message in popup
var msg_popup = func (str...) { gui.popupTip("ZKV1000\n" ~ str, 3) }

###
# just do nothing
var void = func { }

###
# returns decimal part arg
var frac = func (x) { return (x - int(x)) }

###
# rounds regarding proximity
# e.g.:
#   round(1540, 300) gives 1500
#   round(2370, 400) gives 2400
var round = func (x, m = 1) {
    var v = x / m;
    if (frac(v) >= 0.5) v += 1;
    return (int(v) * m);
}

###
# rounds regarless proximity
# e.g.:
#   round_bis(1540, 300) gives 1500
#   round_bis(2370, 400) gives 2000
var round_bis = func (x, m) {
    var r = round(x, m);
    if (r > x) r -= m;
    return r;
}

var alt = vs = vs_abs = ias = tas = pitch = roll = agl = stall = rpm = 0;
var getData = func {
    alt = math.abs(getprop('/instrumentation/altimeter/indicated-altitude-ft'));
    vs = getprop('/velocities/vertical-speed-fps') * 60; 
    ias = getprop('/instrumentation/airspeed-indicator/indicated-speed-kt');
    pitch = getprop('/orientation/pitch-deg');
    roll = getprop('/orientation/pitch-deg');
    agl = getprop('/position/altitude-agl-ft');
    stall = getprop('/sim/alarms/stall-warning');
    gear = getprop('/controls/gears/gear');
}

###
# returns DMS coordinates
# d is decimal longitude or latitude
# c should be one of E, W, S or N
# inspired from FG source: $FGSRC/src/Main/fg_props.cxx 
var DMS = func (d, c) {
    var deg = min = sec = 0.0;
    d = abs(d);
    deg = d + 0.05 / 3600;
    min = (deg - int(deg)) * 60;
    sec = (min - int(min)) * 60 - 0.049;
    return sprintf('%d %02d %04.1f %s', int(deg), int(min), abs(sec), c);
}

var timeUTC = func {
    setprop('/instrumentation/zkv1000/infos/time', sprintf('UTC %02i%02i%02i',
                getprop('/sim/time/utc/hour'),
                getprop('/sim/time/utc/minute'),
                getprop('/sim/time/utc/second')));
}

var timeLCL = func {
    var utc_hour = getprop('/sim/time/utc/hour') + (getprop('/sim/time/local-offset') / 3600);
    if (utc_hour > 23) utc_hour -= 24;
    if (utc_hour < 0)  utc_hour += 24;
    setprop('/instrumentation/zkv1000/infos/time', sprintf('LCL  %02i%02i%02i',
                utc_hour, 
                getprop('/sim/time/utc/minute'),
                getprop('/sim/time/utc/second')));
}

var timeRL = func {
    setprop('/instrumentation/zkv1000/infos/time', sprintf('RL   %02i%02i%02i',
                getprop('/sim/time/real/hour'),
                getprop('/sim/time/real/minute'),
                getprop('/sim/time/real/second')));
}

###
# Loads a fligtplan (route) from a XML file
# replaces existing route by the new one
var loadFPLfromFile = func (file) {
    afcs.getNode('route').removeChildren();
    fgcommand('loadxml', props.Node.new({
              'filename': file,
              'targetnode': afcs.getNode('route').getPath()})
            );
    FPLtoRouteManager();
    msg('route loaded from ' ~ file);
}

var wipeRoute = func {
    var command = props.globals.getNode('/instrumentation/gps/command');
    var v = getprop('/autopilot/route-manager/route/num');
    setprop('/autopilot/route-manager/active', 0);
    setprop('/instrumentation/gps/scratch/index', 0);
    while (v) {
        v -= 1;
        command.setValue('route-delete');
    }
}

var FPLtoRouteManager = func {
    wipeRoute();
    lockSearches();
    var scratch = props.globals.getNode('/instrumentation/gps/scratch');
    var command = scratch.getNode('../command');
    foreach (var waypoint; afcs.getNode('route').getChildren()) {
        scratch.getNode('index').setIntValue(-1);
        searchNearestNavaid(waypoint.getNode('type').getValue(), 1, waypoint.getPath());
        command.setValue('route-insert-after');
    }
    unlockSearches();
}

####
# Search nav facilities
var searchNearestNavaid = func (type, quantity = 1, path = nil) {
    getprop('/instrumentation/zkv1000/searches-locked') or return;
    scratch = props.globals.getNode('/instrumentation/gps/scratch/');
    scratch.getNode('max-results', 1).setIntValue(quantity);
    var lat = lon = -9999;
    if (path != nil) {
        if (props.globals.getNode(path) != nil) {
            lon = getprop(path ~ '/longitude-deg');
            lat = getprop(path ~ '/latitude-deg');
        }
    }
    scratch.getNode('longitude-deg', 1).setDoubleValue(lon);
    scratch.getNode('latitude-deg', 1).setDoubleValue(lat);
    scratch.getNode('type').setValue(type);
    setprop('/instrumentation/gps/command', 'nearest');
}

var lockSearches = func (v = 1) {
    props.globals.getNode('/instrumentation/zkv1000/searches-locked', 1).setBoolValue(v);
}

var unlockSearches = func {
    lockSearches(0);
}

#var dialog = func {
#    var d = gui.Widget.new();
#    d.set({'name': 'ZKV1000 text entry interface', 
#           'layout': 'vbox',
#           'default-padding' : 0});
#    d.addChild('text').
#}

var computeAltitudeDiff = void;
var computeAirspeedDiff = void;
var FLCcomputation = void;
var checkRollAcquisition = void;
var checkPitchAcquisition = void;
var checkTrafficProximity = void;
var manageLandingGears = void;
var checkAbnormalAttitude = void;
var applyFilter = void;