Stabilized metallic foam, a gimmick new flamer fuel

code/game/objects/effects/effect_system/foam.dm

@@ -20,6 +20,7 @@
 	var/expand = 1
 	animate_movement = 0
 	var/metal = FOAM_NOT_METAL
+	var/time_to_solidify = 4 SECONDS
 
 
 /obj/effect/particle_effect/foam/Initialize(mapload, ismetal=0)
@@ -28,7 +29,7 @@
 	metal = ismetal
 	playsound(src, 'sound/effects/bubbles2.ogg', 25, 1, 5)
 	addtimer(CALLBACK(src, PROC_REF(foam_react)), 3 + metal*3)
-	addtimer(CALLBACK(src, PROC_REF(foam_metal_final_react)), 40)
+	addtimer(CALLBACK(src, PROC_REF(foam_metal_final_react)), time_to_solidify)
 
 /obj/effect/particle_effect/foam/proc/foam_react()
 	process()

code/modules/projectiles/gun_attachables.dm

@@ -3221,6 +3221,10 @@ Defined in conflicts.dm of the #defines folder.
 		to_chat(user, SPAN_WARNING("\The [gun] doesn't have enough fuel to launch a projectile!"))
 		return
 
+	if(istype(flamer_reagent, /datum/reagent/foaming_agent/stabilized))
+		to_chat(user, SPAN_WARNING("This chemical will clog the nozzle!"))
+		return
+
 	gun.last_fired = world.time
 	gun.current_mag.reagents.remove_reagent(flamer_reagent.id, FLAME_REAGENT_USE_AMOUNT * fuel_per_projectile)
 

code/modules/projectiles/guns/flamer/flamer.dm

@@ -136,7 +136,10 @@
 		click_empty(user)
 	else
 		user.track_shot(initial(name))
-		unleash_flame(target, user)
+		if(current_mag.reagents.has_reagent("stablefoam"))
+			unleash_foam(target, user)
+		else
+			unleash_flame(target, user)
 		return AUTOFIRE_CONTINUE
 	return NONE
 
@@ -226,6 +229,59 @@
 
 	new /obj/flamer_fire(to_fire, create_cause_data(initial(name), user), R, max_range, current_mag.reagents, flameshape, target, CALLBACK(src, PROC_REF(show_percentage), user), fuel_pressure, fire_type)
 
+/obj/item/weapon/gun/flamer/proc/unleash_foam(atom/target, mob/living/user)
+	last_fired = world.time
+	if(!current_mag || !current_mag.reagents || !current_mag.reagents.reagent_list.len)
+		return
+
+	var/source_turf = get_turf(user)
+	var/foam_range = 6 // the max range the foam will travel
+	var/distance = 0 // the distance traveled
+	var/use_multiplier = 3 // if you want to increase the ammount of foam drained from the tank
+	var/datum/reagent/chemical = current_mag.reagents.reagent_list[1]
+
+	var/turf/turfs[] = get_line(user, target, FALSE)
+	var/turf/first_turf = turfs[1]
+	var/ammount_required = (min(turfs.len, foam_range) * use_multiplier) // the ammount of units that this click requires
+	for(var/turf/turf in turfs)
+
+		if(chemical.volume < ammount_required)
+			foam_range = round(chemical.volume / use_multiplier)
+
+		if(distance >= foam_range)
+			break
+
+		if(turf.density)
+			break
+		else
+			var/obj/effect/particle_effect/foam/checker = new()
+			var/atom/blocked = LinkBlocked(checker, source_turf, turf)
+			if(blocked)
+				break
+
+		if(turf == first_turf) // this is so the first foam tile doesn't expand and touch the user
+			var/datum/effect_system/foam_spread/foam = new()
+			foam.set_up(0.5, turf, metal_foam = FOAM_METAL_TYPE_IRON)
+			foam.start()
+		else
+			var/datum/effect_system/foam_spread/foam = new()
+			foam.set_up(1, turf, metal_foam = FOAM_METAL_TYPE_IRON)
+			foam.start()
+		sleep(2)
+
+		distance++
+
+	var/ammount_used = distance * use_multiplier // the actual ammount of units that we used
+
+	chemical.volume = max(chemical.volume - ammount_used, 0)
+
+	current_mag.reagents.total_volume = chemical.volume // this is needed for show_percentage to work
+
+	if(chemical.volume < use_multiplier) // there aren't enough units left for a single tile of foam, empty the tank
+		current_mag.reagents.clear_reagents()
+
+	show_percentage(user)
+
 /obj/item/weapon/gun/flamer/proc/show_percentage(mob/living/user)
 	if(current_mag)
 		to_chat(user, SPAN_WARNING("The gauge reads: <b>[round(current_mag.get_ammo_percent())]</b>% fuel remains!"))

code/modules/projectiles/magazines/flamer.dm

@@ -90,7 +90,7 @@
 		to_chat(user, SPAN_WARNING("You can't mix fuel mixtures!"))
 		return
 
-	if(!to_add.intensityfire)
+	if(!to_add.intensityfire && to_add.id != "stablefoam")
 		to_chat(user, SPAN_WARNING("This chemical is not potent enough to be used in a flamethrower!"))
 		return
 

code/modules/reagents/chemistry_reactions/other.dm

@@ -360,6 +360,12 @@
 	required_reagents = list("fluorine" = 2, "carbon" = 2, "sulphuric acid" = 1)
 	result_amount = 5
 
+/datum/chemical_reaction/stablefoam
+	name = "Stabilized metallic foam"
+	id = "stablefoam"
+	result = "stablefoam"
+	required_reagents = list("fluorosurfactant" = 1, "iron" = 1, "sulphuric acid" = 1)
+	result_amount = 1
 
 /datum/chemical_reaction/foam
 	name = "Foam"

code/modules/reagents/chemistry_reagents/other.dm

@@ -613,6 +613,15 @@
 	color = "#664B63" // rgb: 102, 75, 99
 	chemclass = CHEM_CLASS_UNCOMMON
 
+/datum/reagent/foaming_agent/stabilized
+	name = "Stabilized metallic foam"
+	id = "stablefoam"
+	description = "Stabilized metallic foam that solidifies when exposed to an open flame"
+	reagent_state = LIQUID
+	color = "#d4b8d1"
+	chemclass = CHEM_CLASS_UNCOMMON
+	properties = list(PROPERTY_TOXIC = 8)
+
 /datum/reagent/nicotine
 	name = "Nicotine"
 	id = "nicotine"