Make sharp weapons apply coating as reagents on hit

code/game/objects/items/__item.dm

@@ -928,10 +928,11 @@ modules/mob/living/human/life.dm if you die, you will be zoomed out.
 /obj/item/proc/on_active_hand()
 	return
 
-/obj/item/proc/has_embedded(mob/living/victim)
+/obj/item/proc/has_embedded(mob/living/victim, def_zone)
 	if(istype(victim))
 		LAZYDISTINCTADD(victim.embedded, src)
 		victim.verbs |= /mob/proc/yank_out_object
+		apply_coating_on_hit(null, victim, def_zone, embedded = TRUE)
 		return TRUE
 	return FALSE
 
@@ -1005,9 +1006,40 @@ modules/mob/living/human/life.dm if you die, you will be zoomed out.
 /obj/item/proc/attack_message_name()
 	return "\a [src]"
 
+/// Returns the fraction of coating applied on a successful hit.
+/obj/item/proc/get_coating_apply_fraction()
+	return is_sharp(src) ? 0.7 ** (w_class - 1) : 0
+
+/// Returns the fraction of applied coating that enters the bloodstream on a successful hit.
+/// This is applied to the result of get_coating_apply_fraction().
+/obj/item/proc/get_coating_inject_fraction()
+	// I put no thought into this implementation.
+	return is_sharp(src) ? 0.8 : 0.2
+
+/obj/item/proc/get_coating_volume()
+	return round(10 * sqrt(w_class))
+
+/// Returns the number of units applied.
+/// User is allowed to be null, target must not be.
+/obj/item/proc/apply_coating_on_hit(mob/user, mob/target, def_zone, embedded = FALSE)
+	if(coating?.total_liquid_volume <= 0)
+		return 0
+	var/transferred_coating_amount = min(get_coating_apply_fraction(), coating.total_liquid_volume)
+	if(embedded)
+		transferred_coating_amount = coating.total_liquid_volume
+	else // user is allowed to be null
+		transferred_coating_amount *= (1 - get_blocked_ratio(def_zone, BRUTE, damage_flags(), armor_penetration, get_attack_force(user)))
+	if(transferred_coating_amount <= 0)
+		return 0
+	// first apply the injected reagents
+	. = poisoned_weapon.coating.trans_to_mob(src, transferred_coating_amount * poisoned_weapon.get_coating_inject_fraction(), CHEM_INJECT, transferred_phases = MAT_PHASE_LIQUID)
+	transferred_coating_amount -= .
+	if(transferred_coating_amount > 0)
+		. += poisoned_weapon.coating.trans_to_mob(src, transferred_coating_amount, CHEM_TOUCH, transferred_phases = MAT_PHASE_LIQUID)
+
 /obj/item/proc/add_coating(reagent_type, amount, data)
 	if(!coating)
-		coating = new/datum/reagents(10, src)
+		coating = new/datum/reagents(get_coating_volume(), src)
 	coating.add_reagent(reagent_type, amount, data)
 
 	if(!blood_overlay)

code/modules/mob/living/living_defense.dm

@@ -229,18 +229,25 @@
 		//Sharp objects will always embed if they do enough damage.
 		//Thrown sharp objects have some momentum already and have a small chance to embed even if the damage is below the threshold
 		if((sharp && prob(sharp_embed_chance)) || (embed_damage > embed_threshold && prob(embed_chance)))
-			affecting.embed_in_organ(I, supplied_wound = (istype(supplied_wound) ? supplied_wound : null))
-			I.has_embedded(src)
+			affecting.embed_in_organ(I, supplied_wound = supplied_wound)
+			I.has_embedded(src, def_zone)
 			. = TRUE
 
 	// Simple embed for mobs with no limbs.
 	if(!. && !length(get_external_organs()))
 		O.forceMove(src)
 		if(isitem(O))
 			var/obj/item/I = O
-			I.has_embedded(src)
+			I.has_embedded(src, def_zone)
 		. = TRUE
 
+	// we want coated items to inject their coating if sharp and not embedded
+	// if it's embedded it's transferred separately in has_embedded
+	// todo: maybe check if the created wound is bleeding instead of checking if it's sharp
+	if(isitem(O) && !. && is_sharp(O))
+		var/obj/item/poisoned_weapon = O
+		poisoned_weapon.apply_coating_on_hit(user, src, def_zone)
+
 	// Allow a tick for throwing/striking to resolve.
 	if(. && direction)
 		addtimer(CALLBACK(src, PROC_REF(check_embed_pinning), O, direction), 1)