[MIRROR] Changes up carbon EMP handling [MDB IGNORE] (#2990)

* Changes up carbon EMP handling (#83857)

## About The Pull Request

The organ refactor 6 months ago changed up organs, making them be
actually inside bodyparts and the mob. This introduced the bug of all
emp effects being called twice on everything thanks to how /mob/living
handles it (Fixed in this PR), but also some new stuff:

Made bodyparts handle organ EMPs. This also means we can now have
support for bodyparts with EMP_PROTECT_CONTENTS protecting the organs
inside.
Made a new proc for bodyparts once they are successfully hit by an emp.
Makes it much easier to add overrides for the behaviour.
Fixed emps hitting bodyparts twice

## Why It's Good For The Game

It lays a groundwork for some interesting limb concepts, and makes organ
emps make a bit more sense.

Fixes a bug that laid unnoticed for 6 months.

## Changelog

:cl:
fix: EMPs on carbons no longer happen twice
code: Moves organ emps under bodyparts, changes how bodyparts handle emp
effects
/:cl:

---------

Co-authored-by: Time-Green <[email protected]>

* Changes up carbon EMP handling

---------

Co-authored-by: Waterpig <[email protected]>
Co-authored-by: Time-Green <[email protected]>
Co-authored-by: NovaBot13 <[email protected]>

code/modules/mob/living/carbon/carbon_defense.dm

@@ -240,15 +240,6 @@
 		show_message(span_userdanger("The blob attacks!"))
 		adjustBruteLoss(10)
 
-/mob/living/carbon/emp_act(severity)
-	. = ..()
-	if(. & EMP_PROTECT_CONTENTS)
-		return
-	for(var/obj/item/organ/organ as anything in organs)
-		organ.emp_act(severity)
-	for(var/obj/item/bodypart/bodypart as anything in src.bodyparts)
-		bodypart.emp_act(severity)
-
 ///Adds to the parent by also adding functionality to propagate shocks through pulling and doing some fluff effects.
 /mob/living/carbon/electrocute_act(shock_damage, source, siemens_coeff = 1, flags = NONE, jitter_time = 20 SECONDS, stutter_time = 4 SECONDS, stun_duration = 4 SECONDS)
 	. = ..()

code/modules/surgery/bodyparts/_bodyparts.dm

@@ -1407,12 +1407,24 @@
 	else
 		update_icon_dropped()
 
-// Note: Does NOT return EMP protection value from parent call or pass it on to subtypes
+// Note: For effects on subtypes, use the emp_effect() proc instead
 /obj/item/bodypart/emp_act(severity)
 	var/protection = ..()
-	if((protection & EMP_PROTECT_WIRES) || !IS_ROBOTIC_LIMB(src))
-		return FALSE
+	// If the limb doesn't protect contents, strike them first
+	if(!(protection & EMP_PROTECT_CONTENTS))
+		for(var/atom/content as anything in contents)
+			content.emp_act(severity)
+
+	if((protection & (EMP_PROTECT_WIRES | EMP_PROTECT_SELF)))
+		return protection
 
+	emp_effect(severity, protection)
+	return protection
+
+/// The actual effect of EMPs on the limb. Allows children to override it however they want
+/obj/item/bodypart/proc/emp_effect(severity, protection)
+	if(!IS_ROBOTIC_LIMB(src))
+		return FALSE
 	// with defines at the time of writing, this is 2 brute and 1.5 burn
 	// 2 + 1.5 = 3,5, with 6 limbs thats 21, on a heavy 42
 	// 42 * 0.8 = 33.6

code/modules/surgery/bodyparts/robot_bodyparts.dm

@@ -115,7 +115,7 @@
 	damage_examines = list(BRUTE = ROBOTIC_BRUTE_EXAMINE_TEXT, BURN = ROBOTIC_BURN_EXAMINE_TEXT)
 	bodypart_flags = BODYPART_UNHUSKABLE
 
-/obj/item/bodypart/leg/left/robot/emp_act(severity)
+/obj/item/bodypart/leg/left/robot/emp_effect(severity, protection)
 	. = ..()
 	if(!. || isnull(owner))
 		return
@@ -125,8 +125,9 @@
 		knockdown_time *= 2
 	owner.Knockdown(knockdown_time)
 	if(owner.incapacitated(IGNORE_RESTRAINTS|IGNORE_GRAB)) // So the message isn't duplicated. If they were stunned beforehand by something else, then the message not showing makes more sense anyways.
-		return
+		return FALSE
 	to_chat(owner, span_danger("As your [plaintext_zone] unexpectedly malfunctions, it causes you to fall to the ground!"))
+	return
 
 /obj/item/bodypart/leg/right/robot
 	name = "cyborg right leg"
@@ -163,7 +164,7 @@
 	damage_examines = list(BRUTE = ROBOTIC_BRUTE_EXAMINE_TEXT, BURN = ROBOTIC_BURN_EXAMINE_TEXT)
 	bodypart_flags = BODYPART_UNHUSKABLE
 
-/obj/item/bodypart/leg/right/robot/emp_act(severity)
+/obj/item/bodypart/leg/right/robot/emp_effect(severity, protection)
 	. = ..()
 	if(!. || isnull(owner))
 		return
@@ -173,8 +174,9 @@
 		knockdown_time *= 2
 	owner.Knockdown(knockdown_time)
 	if(owner.incapacitated(IGNORE_RESTRAINTS|IGNORE_GRAB)) // So the message isn't duplicated. If they were stunned beforehand by something else, then the message not showing makes more sense anyways.
-		return
+		return FALSE
 	to_chat(owner, span_danger("As your [plaintext_zone] unexpectedly malfunctions, it causes you to fall to the ground!"))
+	return
 
 /obj/item/bodypart/chest/robot
 	name = "cyborg torso"
@@ -215,7 +217,7 @@
 	var/wired = FALSE
 	var/obj/item/stock_parts/cell/cell = null
 
-/obj/item/bodypart/chest/robot/emp_act(severity)
+/obj/item/bodypart/chest/robot/emp_effect(severity, protection)
 	. = ..()
 	if(!. || isnull(owner))
 		return
@@ -236,6 +238,7 @@
 		to_chat(owner, span_danger("Your [plaintext_zone]'s logic boards temporarily become unresponsive!"))
 		owner.Stun(stun_time)
 	owner.Shake(pixelshiftx = shift_x, pixelshifty = shift_y, duration = shake_duration)
+	return
 
 /obj/item/bodypart/chest/robot/get_cell()
 	return cell
@@ -394,7 +397,7 @@
 
 #define EMP_GLITCH "EMP_GLITCH"
 
-/obj/item/bodypart/head/robot/emp_act(severity)
+/obj/item/bodypart/head/robot/emp_effect(severity, protection)
 	. = ..()
 	if(!. || isnull(owner))
 		return
@@ -408,6 +411,7 @@
 	owner.add_client_colour(/datum/client_colour/malfunction)
 
 	addtimer(CALLBACK(owner, TYPE_PROC_REF(/mob/living/carbon/human, remove_client_colour), /datum/client_colour/malfunction), glitch_duration)
+	return
 
 #undef EMP_GLITCH