##################################
# Icing Model for the A320Family #
# Code by Jonathan Redpath 		 #
##################################

var icingInit = func {
	setprop("/systems/icing/severity", "0"); # maximum severity: we will make it random
	setprop("/systems/icing/factor", 0.0); # the factor is how many inches we add per second
	setprop("/systems/icing/max-spread-degc", 0.0);
	setprop("/systems/icing/icingcond", 0);
	setprop("/controls/switches/windowprobeheat", 0);
	setprop("/controls/switches/windowprobeheatfault", 0);
	icing_timer.start();
}

var icingModel = func {
	var dewpoint = getprop("/environment/dewpoint-degc");
	var temperature = getprop("/environment/temperature-degc");
	var speed = getprop("/velocities/airspeed-kt");
	var visibility = getprop("/environment/effective-visibility-m");
	var severity = getprop("/systems/icing/severity");
	var factor = getprop("/systems/icing/factor");
	var maxSpread = getprop("/systems/icing/max-spread-degc");
	var icingCond = getprop("/systems/icing/icingcond");

	if (severity == "0") {
		setprop("/systems/icing/factor", -0.00000166);
	} else if (severity == "1") {
		setprop("/systems/icing/factor", 0.00000277);
	} else if (severity == "2") {
		setprop("/systems/icing/factor", 0.00000277);
	} else if (severity == "3") {
		setprop("/systems/icing/factor", 0.00000554);
	} else if (severity == "4") {
		setprop("/systems/icing/factor", 0.00001108);
	} else if (severity == "5") {
		setprop("/systems/icing/factor", 0.00002216);
	}
	
	if (temperature >= 0 or !icingCond) {
		setprop("/systems/icing/severity", "0");
	} else if (temperature < 0 and temperature >= -2 and icingCond) {
		setprop("/systems/icing/severity", "1");
	} else if (temperature < -2 and temperature >= -12 and icingCond) {
		setprop("/systems/icing/severity", "3");
	} else if (temperature < -12 and temperature >= -30 and icingCond) {
		setprop("/systems/icing/severity", "5");
	} else if (temperature < -30 and temperature >= -40 and icingCond) {
		setprop("/systems/icing/severity", "3");
	} else if (temperature < -40 and temperature >= -99 and icingCond) {
		setprop("/systems/icing/severity", "1");
	}
	
	var icing1 = getprop("/sim/model/icing/iceable[0]/ice-inches");
	var sensitive1 = getprop("/sim/model/icing/iceable[0]/sensitivity");
	var v = icing1 + (factor * sensitive1);
	if (icing1 < 0.0) {
		setprop("/sim/model/icing/iceable[0]/ice-inches", 0.0);
	} else {
		setprop("/sim/model/icing/iceable[0]/ice-inches", v);
	}
	
	var icing2 = getprop("/sim/model/icing/iceable[1]/ice-inches");
	var sensitive2 = getprop("/sim/model/icing/iceable[1]/sensitivity");
	var u = icing2 + (factor * sensitive2);
	if (icing2 < 0.0) {
		setprop("/sim/model/icing/iceable[1]/ice-inches", 0.0);
	} else {
		setprop("/sim/model/icing/iceable[1]/ice-inches", u);
	}
	
	var icing3 = getprop("/sim/model/icing/iceable[2]/ice-inches");
	var sensitive3 = getprop("/sim/model/icing/iceable[2]/sensitivity");
	var t = icing3 + (factor * sensitive3);
	if (icing3 < 0.0) {
		setprop("/sim/model/icing/iceable[2]/ice-inches", 0.0);
	} else {
		setprop("/sim/model/icing/iceable[2]/ice-inches", t);
	}
	
	var icing4 = getprop("/sim/model/icing/iceable[3]/ice-inches");
	var sensitive4 = getprop("/sim/model/icing/iceable[3]/sensitivity");
	var s = icing4 + (factor * sensitive4);
	if (icing4 < 0.0) {
		setprop("/sim/model/icing/iceable[3]/ice-inches", 0.0);
	} else {
		setprop("/sim/model/icing/iceable[3]/ice-inches", s);
	}
	
	var icing5 = getprop("/sim/model/icing/iceable[4]/ice-inches");
	var sensitive5 = getprop("/sim/model/icing/iceable[4]/sensitivity");
	var r = icing5 + (factor * sensitive5);
	if (icing5 < 0.0) {
		setprop("/sim/model/icing/iceable[4]/ice-inches", 0.0);
	} else {
		setprop("/sim/model/icing/iceable[4]/ice-inches", r);
	}
	
	var icing6 = getprop("/sim/model/icing/iceable[5]/ice-inches");
	var sensitive6 = getprop("/sim/model/icing/iceable[5]/sensitivity");
	var q = icing6 + (factor * sensitive6);
	if (icing6 < 0.0) {
		setprop("/sim/model/icing/iceable[5]/ice-inches", 0.0);
	} else {
		setprop("/sim/model/icing/iceable[5]/ice-inches", q);
	}
	
	# Do we create ice?
	var spread = temperature - dewpoint;
	if((spread < maxSpread and temperature < 0) or (temperature < 0 and visibility < 1000)) { # freezing fog or low temp and below dp
		setprop("/systems/icing/icingcond", 1);
	} else {
		setprop("/systems/icing/icingcond", 0);
	}

	setlistener("/controls/switches/windowprobeheat", func {
		var windowprb = getprop("/controls/switches/windowprobeheat");
		var fault = getprop("/controls/switches/windowprobeheatfault");
		if (windowprb == 0.5) { # if in auto 
			var wowl = getprop("/gear/gear[1]/wow");
			var wowr = getprop("/gear/gear[2]/wow");
			var stateL = getprop("/engines/engine[0]/state");
			var stateR = getprop("/engines/engine[1]/state");
			var fault = getprop("/controls/switches/windowprobeheatfault");
			if (!wowl or !wowr and !fault) {
				setprop("/controls/deice/windowprobeheat", 1);
			} else if (stateL == 3 or stateR == 3 and !fault) {
				setprop("/controls/deice/windowprobeheat", 1);
			}
			} else if (windowprb == 1 and !fault) { # if in ON
				setprop("/controls/deice/windowprobeheat", 1);
			} else if (fault) {
				setprop("/controls/deice/windowprobeheat", 0);
			} else {
				setprop("/controls/deice/windowprobeheat", 0);
		}
	});
}

###################
# Update Function #
###################

var update_Icing = func {
	icingModel();
}

var icing_timer = maketimer(0.2, update_Icing);