Let Them Eat Dirt - Elzu Rooting (shiptest-ss13#2949)

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## About The Pull Request

Adds the ability for elzu to root on top of good soil turfs (dirt,
planetary grass, etc) to feed.

Elzu will get some minor healing and an additional mood buff along with
the charge they get from rooting. You can't root in thick clothing like
space suits due to them needing a direct connection to the ground.

Being moved while rooted will uproot you, dealing damage to your torso
and legs.

Also changes the max age for elzu to 300.

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## Why It's Good For The Game

The ELZOOT.

Anyways, elzu should be able to root in lore and that being reflected in
gameplay is probably good.

In lore, elzu that only root are supposed to be able to hit up to 300
years old. So I bumped up the age max since they can root ingame now.

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## Changelog

:cl:
add: Elzu rooting
tweak: Max age for elzu characters can be 300.
/:cl:

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---------

Signed-off-by: Gristlebee <[email protected]>
Signed-off-by: thgvr <[email protected]>
Co-authored-by: FalloutFalcon <[email protected]>
Co-authored-by: thgvr <[email protected]>

code/__DEFINES/dcs/signals.dm

@@ -763,3 +763,6 @@
 
 ///called in /obj/item/gun/process_chamber (src)
 #define COMSIG_GUN_CHAMBER_PROCESSED "gun_chamber_processed"
+
+///called when an elzu should unroot
+#define COMSIG_DIGOUT "dig_out"

code/datums/mood_events/generic_positive_events.dm

@@ -239,3 +239,8 @@
 	description = "Fishing is relaxing"
 	mood_change = 5
 	timeout = 3 MINUTES
+
+/datum/mood_event/root
+	description = span_nicegreen("I rooted recently, it feels good to charge naturally.\n")
+	mood_change = 5
+	timeout = 5 MINUTES

code/datums/status_effects/neutral.dm

@@ -275,3 +275,29 @@
 /atom/movable/screen/alert/status_effect/surrender/Click(location, control, params)
 	. = ..()
 	owner.emote("surrender")
+
+/datum/status_effect/rooted
+	id = "rooted"
+	alert_type = /atom/movable/screen/alert/status_effect/rooted
+
+/datum/status_effect/rooted/on_apply()
+	. = ..()
+	ADD_TRAIT(owner,TRAIT_IMMOBILIZED, TRAIT_STATUS_EFFECT(id))
+	ADD_TRAIT(owner,TRAIT_PUSHIMMUNE, TRAIT_STATUS_EFFECT(id))
+	SEND_SIGNAL(owner, COMSIG_ADD_MOOD_EVENT, "root", /datum/mood_event/root)
+
+/datum/status_effect/rooted/on_remove()
+	. = ..()
+	REMOVE_TRAIT(owner,TRAIT_IMMOBILIZED, TRAIT_STATUS_EFFECT(id))
+	REMOVE_TRAIT(owner,TRAIT_PUSHIMMUNE, TRAIT_STATUS_EFFECT(id))
+
+/atom/movable/screen/alert/status_effect/rooted
+	name = "Rooted"
+	desc = "You're currently rooted into the ground and can't move. Click here to start digging yourself out."
+	icon_state = "dig_out"
+
+/atom/movable/screen/alert/status_effect/rooted/Click(location, control, params)
+	. = ..()
+	to_chat(owner, span_notice("You begin digging yourself free."))
+	SEND_SIGNAL(owner,COMSIG_DIGOUT)
+