sort of working fire selector, still need to get the safety stuff figured out and finish getting the selector working properly

code/__DEFINES/dcs/signals.dm

@@ -321,6 +321,12 @@
 ///from base of mob/AltClickOn(): (atom/A)
 #define COMSIG_MOB_ALTCLICKON "mob_altclickon"
 
+//Gun signals
+///When a gun is switched to automatic fire mode
+#define COMSIG_GUN_AUTOFIRE_SELECTED "gun_autofire_selected"
+///When a gun is switched off of automatic fire mode
+#define COMSIG_GUN_AUTOFIRE_DESELECTED "gun_autofire_deselected"
+
 // Lighting:
 ///from base of [atom/proc/set_light]: (l_range, l_power, l_color, l_on)
 #define COMSIG_ATOM_SET_LIGHT "atom_set_light"

code/__DEFINES/gun.dm

@@ -0,0 +1,3 @@
+#define SELECT_SEMI_AUTOMATIC 1
+#define SELECT_BURST_SHOT 2
+#define SELECT_FULLY_AUTOMATIC 3

code/datums/action.dm

@@ -23,6 +23,8 @@
 	var/icon_icon = 'icons/mob/actions.dmi' //This is the file for the ACTION icon
 	var/button_icon_state = "default" //And this is the state for the action icon
 	var/mob/owner
+	///List of all mobs that are viewing our action button -> A unique movable for them to view.
+	var/list/viewers = list()
 
 /datum/action/New(Target)
 	link_to(Target)
@@ -121,6 +123,11 @@
 			return FALSE
 	return TRUE
 
+/datum/action/proc/UpdateButtons(status_only, force)
+	for(var/datum/hud/hud in viewers)
+		var/atom/movable/screen/movable/button = viewers[hud]
+		UpdateButtonIcon(button, status_only, force)
+
 /datum/action/proc/UpdateButtonIcon(status_only = FALSE, force = FALSE)
 	if(!button)
 		return
@@ -217,6 +224,8 @@
 	name = "Toggle Hood"
 
 /datum/action/item_action/toggle_firemode
+	icon_icon = 'icons/mob/actions/actions_items.dmi'
+	button_icon_state = "fireselect_no"
 	name = "Toggle Firemode"
 
 /datum/action/item_action/rcl_col

code/modules/projectiles/gun.dm

@@ -89,6 +89,19 @@
 	var/zoom_out_amt = 0
 	var/datum/action/item_action/toggle_scope_zoom/azoom
 
+	var/safety = FALSE /// Internal variable for keeping track whether the safety is on or off
+	var/has_gun_safety = FALSE /// Whether the gun actually has a gun safety
+	var/datum/action/item_action/toggle_safety/toggle_safety_action
+
+	var/datum/action/item_action/toggle_firemode/firemode_action
+	/// Current fire selection, can choose between burst, single, and full auto.
+	var/fire_select = SELECT_SEMI_AUTOMATIC
+	var/fire_select_index = 1
+	/// What modes does this weapon have? Put SELECT_FULLY_AUTOMATIC in here to enable fully automatic behaviours.
+	var/list/fire_select_modes = list(SELECT_SEMI_AUTOMATIC)
+	/// if i`1t has an icon for a selector switch indicating current firemode.
+	var/selector_switch_icon = FALSE
+
 	var/dualwield_spread_mult = 1		//dualwield spread multiplier
 
 	/// Just 'slightly' snowflakey way to modify projectile damage for projectiles fired from this gun.
@@ -97,18 +110,53 @@
 
 	/// directional recoil multiplier
 	var/dir_recoil_amp = 10
+/datum/action/item_action/toggle_safety
+	name = "Toggle Safety"
+	icon_icon = 'icons/hud/actions.dmi'
+	button_icon_state = "safety_on"
 
-/obj/item/gun/Initialize(mapload)
+/obj/item/gun/ui_action_click(mob/user, actiontype)
+	if(istype(actiontype, /datum/action/item_action/toggle_firemode))
+		fire_select()
+	else if(istype(actiontype, toggle_safety_action))
+		toggle_safety(user)
+	else
+		..()
+
+
+/obj/item/gun/Initialize()
 	. = ..()
-	if(no_pin_required)
-		pin = null
-	else if(pin)
+	if(pin)
 		pin = new pin(src)
+
 	if(gun_light)
-		alight = new (src)
+		alight = new(src)
+
 	if(zoomable)
 		azoom = new (src)
 
+	if(has_gun_safety)
+		safety = TRUE
+		toggle_safety_action = new(src)
+
+	if(burst_size > 1 && !(SELECT_BURST_SHOT in fire_select_modes))
+		fire_select_modes.Add(SELECT_BURST_SHOT)
+	else if(burst_size <= 1 && (SELECT_BURST_SHOT in fire_select_modes))
+		fire_select_modes.Remove(SELECT_BURST_SHOT)
+
+	burst_size = 1
+
+	sortList(fire_select_modes, /proc/cmp_numeric_asc)
+
+	if(fire_select_modes.len > 1)
+		firemode_action = new(src)
+		firemode_action.button_icon_state = "fireselect_[fire_select]"
+		firemode_action.UpdateButtonIcon()
+/obj/item/gun/ComponentInitialize()
+	. = ..()
+	if(SELECT_FULLY_AUTOMATIC in fire_select_modes)
+		AddComponent(/datum/component/automatic_fire, fire_delay)
+
 /obj/item/gun/Destroy()
 	if(pin)
 		QDEL_NULL(pin)
@@ -118,6 +166,10 @@
 		QDEL_NULL(bayonet)
 	if(chambered)
 		QDEL_NULL(chambered)
+	if(toggle_safety_action)
+		QDEL_NULL(toggle_safety_action)
+	if(firemode_action)
+		QDEL_NULL(firemode_action)
 	return ..()
 
 /obj/item/gun/examine(mob/user)
@@ -143,6 +195,61 @@
 	else if(can_bayonet)
 		. += "It has a <b>bayonet</b> lug on it."
 
+/obj/item/gun/proc/fire_select()
+	var/mob/living/carbon/human/user = usr
+
+	var/max_mode = fire_select_modes.len
+
+	if(max_mode <= 1)
+		balloon_alert(user, "only one firemode!")
+		return
+
+	fire_select_index = 1 + fire_select_index % max_mode // Magic math to cycle through this shit!
+
+	fire_select = fire_select_modes[fire_select_index]
+
+	switch(fire_select)
+		if(SELECT_SEMI_AUTOMATIC)
+			burst_size = 1
+			fire_delay = 0
+			SEND_SIGNAL(src, COMSIG_GUN_AUTOFIRE_DESELECTED, user)
+			balloon_alert(user, "semi-automatic")
+		if(SELECT_BURST_SHOT)
+			burst_size = initial(burst_size)
+			fire_delay = initial(fire_delay)
+			SEND_SIGNAL(src, COMSIG_GUN_AUTOFIRE_DESELECTED, user)
+			balloon_alert(user, "[burst_size]-round burst")
+		if(SELECT_FULLY_AUTOMATIC)
+			burst_size = 1
+			SEND_SIGNAL(src, COMSIG_GUN_AUTOFIRE_SELECTED, user)
+			balloon_alert(user, "automatic")
+
+	playsound(user, 'sound/weapons/empty.ogg', 100, TRUE)
+	update_appearance()
+	firemode_action.button_icon_state = "fireselect_[fire_select]"
+	firemode_action.UpdateButtons()
+	//SEND_SIGNAL(src, COMSIG_UPDATE_AMMO_HUD) I'll need this later
+	return TRUE
+
+/obj/item/gun/proc/toggle_safety(mob/user, override)
+	if(!has_gun_safety)
+		return
+	if(override)
+		if(override == "off")
+			safety = FALSE
+		else
+			safety = TRUE
+	else
+		safety = !safety
+	toggle_safety_action.button_icon_state = "safety_[safety ? "on" : "off"]"
+	toggle_safety_action.UpdateButtons()
+	playsound(src, 'sound/weapons/empty.ogg', 100, TRUE)
+	user.visible_message(
+		span_notice("[user] toggles [src]'s safety [safety ? "<font color='#00ff15'>ON</font>" : "<font color='#ff0000'>OFF</font>"]."),
+		span_notice("You toggle [src]'s safety [safety ? "<font color='#00ff15'>ON</font>" : "<font color='#ff0000'>OFF</font>"].")
+	)
+	//SEND_SIGNAL(src, COMSIG_UPDATE_AMMO_HUD) once again, needed later
+
 /obj/item/gun/equipped(mob/living/user, slot)
 	. = ..()
 	if(zoomed && user.get_active_held_item() != src)

code/modules/projectiles/guns/ballistic/automatic.dm

@@ -6,7 +6,7 @@
 	can_suppress = TRUE
 	burst_size = 3
 	burst_shot_delay = 2
-	actions_types = list(/datum/action/item_action/toggle_firemode)
+	fire_select_modes = list(SELECT_SEMI_AUTOMATIC, SELECT_BURST_SHOT, SELECT_FULLY_AUTOMATIC)
 
 /obj/item/gun/ballistic/automatic/proto
 	name = "\improper Nanotrasen Saber SMG"

code/modules/projectiles/guns/ballistic/launchers.dm

@@ -39,7 +39,7 @@
 	mag_type = /obj/item/ammo_box/magazine/m75
 	burst_size = 1
 	fire_delay = 0
-	actions_types = list()
+	fire_select_modes = list(SELECT_SEMI_AUTOMATIC)
 	casing_ejector = FALSE
 
 /obj/item/gun/ballistic/automatic/gyropistol/update_icon_state()

code/modules/projectiles/guns/ballistic/pistol.dm

@@ -7,7 +7,7 @@
 	can_suppress = TRUE
 	burst_size = 1
 	fire_delay = 0
-	actions_types = list()
+	fire_select_modes = list(SELECT_SEMI_AUTOMATIC)
 	automatic_burst_overlay = FALSE
 
 /obj/item/gun/ballistic/automatic/pistol/no_mag
@@ -104,7 +104,7 @@
 	mag_type = /obj/item/ammo_box/magazine/pistolm9mm
 	burst_size = 3
 	fire_delay = 2
-	actions_types = list(/datum/action/item_action/toggle_firemode)
+	fire_select_modes = list(SELECT_SEMI_AUTOMATIC, SELECT_BURST_SHOT, SELECT_FULLY_AUTOMATIC)
 
 /obj/item/gun/ballistic/automatic/pistol/stickman
 	name = "flat gun"
@@ -137,7 +137,7 @@
 	burst_size = 1
 	can_suppress = FALSE
 	w_class = WEIGHT_CLASS_NORMAL
-	actions_types = list()
+	fire_select_modes = list(SELECT_SEMI_AUTOMATIC)
 	fire_sound = 'sound/weapons/noscope.ogg'
 	spread = 20		//damn thing has no rifling.
 	automatic_burst_overlay = FALSE

tgstation.dme

@@ -56,6 +56,7 @@
 #include "code\__DEFINES\fantasy_affixes.dm"
 #include "code\__DEFINES\food.dm"
 #include "code\__DEFINES\footsteps.dm"
+#include "code\__DEFINES\gun.dm"
 #include "code\__DEFINES\hud.dm"
 #include "code\__DEFINES\instruments.dm"
 #include "code\__DEFINES\integrated_electronics.dm"