Adds emergency lights, built into light fixtures

code/modules/power/apc.dm

@@ -89,6 +89,7 @@
 	var/auto_name = 0
 	var/failure_timer = 0
 	var/force_update = 0
+	var/emergency_lights = FALSE
 	var/update_state = -1
 	var/update_overlay = -1
 	var/icon_update_needed = FALSE
@@ -760,6 +761,7 @@
 		"coverLocked" = coverlocked,
 		"siliconUser" = user.has_unlimited_silicon_privilege || user.using_power_flow_console(),
 		"malfStatus" = get_malf_status(user),
+		"emergencyLights" = !emergency_lights,
 
 		"powerChannels" = list(
 			list(
@@ -899,6 +901,14 @@
 			failure_timer = 0
 			update_icon()
 			update()
+		if("emergency_lighting")
+			emergency_lights = !emergency_lights
+			for(var/area/A in area.related)
+				for(var/obj/machinery/light/L in A)
+					if(!initial(L.no_emergency)) //If there was an override set on creation, keep that override
+						L.no_emergency = emergency_lights
+						INVOKE_ASYNC(L, /obj/machinery/light/.proc/update, FALSE)
+					CHECK_TICK
 	return 1
 
 /obj/machinery/power/apc/proc/toggle_breaker()

code/modules/power/cell.dm

@@ -343,3 +343,17 @@
 
 /obj/item/stock_parts/cell/beam_rifle/emp_act(severity)
 	charge = Clamp((charge-(10000/severity)),0,maxcharge)
+
+/obj/item/stock_parts/cell/emergency_light
+	name = "miniature power cell"
+	desc = "A tiny power cell with a very low power capacity. Used in light fixtures to power them in the event of an outage."
+	maxcharge = 120 //Emergency lights use 0.2 W per tick, meaning ~10 minutes of emergency power from a cell
+	materials = list(MAT_GLASS = 20)
+	rating = 1
+	w_class = WEIGHT_CLASS_TINY
+
+/obj/item/stock_parts/cell/emergency_light/Initialize()
+	. = ..()
+	var/area/A = get_area(src)
+	if(!A.lightswitch || !A.light_power)
+		charge = 0 //For naturally depowered areas, we start with no power

code/modules/power/lighting.dm

@@ -49,12 +49,22 @@
 	var/fixture_type = "tube"
 	var/sheets_refunded = 2
 	var/obj/machinery/light/newlight = null
+	var/obj/item/stock_parts/cell/cell
 
-/obj/structure/light_construct/New(loc, ndir, building)
-	..()
+	var/cell_connectors = TRUE
+
+/obj/structure/light_construct/Initialize(mapload, ndir, building)
+	. = ..()
 	if(building)
 		setDir(ndir)
 
+/obj/structure/light_construct/Destroy()
+	QDEL_NULL(cell)
+	return ..()
+
+/obj/structure/light_construct/get_cell()
+	return cell
+
 /obj/structure/light_construct/examine(mob/user)
 	..()
 	switch(src.stage)
@@ -64,9 +74,38 @@
 			to_chat(user, "It's wired.")
 		if(3)
 			to_chat(user, "The casing is closed.")
+	if(cell_connectors)
+		if(cell)
+			to_chat(user, "You see [cell] inside the casing.")
+		else
+			to_chat(user, "The casing has no power cell for backup power.")
+	else
+		to_chat(user, "<span class='danger'>This casing doesn't support power cells for backup power.</span>")
+		return
 
 /obj/structure/light_construct/attackby(obj/item/W, mob/user, params)
 	add_fingerprint(user)
+	if(istype(W, /obj/item/stock_parts/cell))
+		if(!cell_connectors)
+			to_chat(user, "<span class='warning'>This [name] can't support a power cell!</span>")
+			return
+		if(W.flags_1 & NODROP_1)
+			to_chat(user, "<span class='warning'>[W] is stuck to your hand!</span>")
+			return
+		user.dropItemToGround(W)
+		if(cell)
+			user.visible_message("<span class='notice'>[user] swaps [W] out for [src]'s cell.</span>", \
+			"<span class='notice'>You swap [src]'s power cells.</span>")
+			cell.forceMove(drop_location())
+			user.put_in_hands(cell)
+		else
+			user.visible_message("<span class='notice'>[user] hooks up [W] to [src].</span>", \
+			"<span class='notice'>You add [W] to [src].</span>")
+		playsound(src, 'sound/machines/click.ogg', 50, TRUE)
+		W.forceMove(src)
+		cell = W
+		add_fingerprint(user)
+		return
 	switch(stage)
 		if(1)
 			if(istype(W, /obj/item/wrench))
@@ -124,6 +163,10 @@
 						newlight = new /obj/machinery/light/small/built(loc)
 				newlight.setDir(dir)
 				transfer_fingerprints_to(newlight)
+				if(cell)
+					newlight.cell = cell
+					cell.forceMove(newlight)
+					cell = null
 				qdel(src)
 				return
 	return ..()
@@ -173,6 +216,11 @@
 
 	var/rigged = 0				// true if rigged to explode
 
+	var/obj/item/stock_parts/cell/cell
+	var/start_with_cell = TRUE	// if true, this fixture generates a very weak cell at roundstart
+	var/emergency_mode = FALSE	// if true, the light is in emergency mode
+	var/no_emergency = FALSE	// if true, this light cannot ever have an emergency mode
+
 // the smaller bulb light fixture
 
 /obj/machinery/light/small
@@ -192,8 +240,14 @@
 
 /obj/machinery/light/built
 	icon_state = "tube-empty"
+	start_with_cell = FALSE
 
+<<<<<<< HEAD
 /obj/machinery/light/built/New()
+=======
+/obj/machinery/light/built/Initialize()
+	. = ..()
+>>>>>>> fe816da... Adds emergency lights, built into light fixtures (#33213)
 	status = LIGHT_EMPTY
 	update(0)
 	..()
@@ -208,8 +262,15 @@
 
 
 // create a new lighting fixture
+<<<<<<< HEAD
 /obj/machinery/light/New()
 	..()
+=======
+/obj/machinery/light/Initialize()
+	. = ..()
+	if(start_with_cell && !no_emergency)
+		cell = new/obj/item/stock_parts/cell/emergency_light(src)
+>>>>>>> fe816da... Adds emergency lights, built into light fixtures (#33213)
 	spawn(2)
 		switch(fitting)
 			if("tube")
@@ -228,13 +289,17 @@
 	if(A)
 		on = FALSE
 //		A.update_lights()
+	QDEL_NULL(cell)
 	return ..()
 
 /obj/machinery/light/update_icon()
 
 	switch(status)		// set icon_states
 		if(LIGHT_OK)
-			icon_state = "[base_state][on]"
+			if(emergency_mode)
+				icon_state = "[base_state]_emergency"
+			else
+				icon_state = "[base_state][on]"
 		if(LIGHT_EMPTY)
 			icon_state = "[base_state]-empty"
 			on = FALSE
@@ -249,7 +314,7 @@
 // update the icon_state and luminosity of the light depending on its state
 /obj/machinery/light/proc/update(trigger = 1)
 
-	update_icon()
+	emergency_mode = FALSE
 	if(on)
 		if(!light || light.light_range != brightness)
 			switchcount++
@@ -261,10 +326,15 @@
 					burn_out()
 			else
 				use_power = ACTIVE_POWER_USE
-				set_light(brightness)
+				set_light(brightness, 1, "#FFFFFF")
+	else if(has_emergency_power() && !turned_off())
+		use_power = IDLE_POWER_USE
+		emergency_mode = TRUE
+		process() //Force a process tick to update the light immediately
 	else
 		use_power = IDLE_POWER_USE
 		set_light(0)
+	update_icon()
 
 	active_power_usage = (brightness * 10)
 	if(on != on_gs)
@@ -276,6 +346,12 @@
 			removeStaticPower(static_power_used, STATIC_LIGHT)
 
 
+/obj/machinery/light/process()
+	if(has_power() && cell)
+		cell.charge = min(cell.maxcharge, cell.charge + 0.2) //Recharge emergency power automatically while not using it
+	if(emergency_mode && !use_emergency_power(0.2))
+		update(FALSE) //Disables emergency mode and sets the color to normal
+
 /obj/machinery/light/proc/burn_out()
 	if(status == LIGHT_OK)
 		status = LIGHT_BURNED
@@ -289,6 +365,9 @@
 	on = (s && status == LIGHT_OK)
 	update()
 
+/obj/machinery/light/get_cell()
+	return cell
+
 // examine verb
 /obj/machinery/light/examine(mob/user)
 	..()
@@ -301,6 +380,8 @@
 			to_chat(user, "The [fitting] is burnt out.")
 		if(LIGHT_BROKEN)
 			to_chat(user, "The [fitting] has been smashed.")
+	if(cell)
+		to_chat(user, "Its backup power charge meter reads [(cell.charge / cell.maxcharge) * 100]%.")
 
 
 
@@ -384,6 +465,10 @@
 				drop_light_tube()
 			new /obj/item/stack/cable_coil(loc, 1, "red")
 		transfer_fingerprints_to(newlight)
+		if(cell)
+			newlight.cell = cell
+			cell.forceMove(newlight)
+			cell = null
 	qdel(src)
 
 /obj/machinery/light/attacked_by(obj/item/I, mob/living/user)
@@ -415,6 +500,11 @@
 		if(BURN)
 			playsound(src.loc, 'sound/items/welder.ogg', 100, 1)
 
+// returns if the light has power /but/ is manually turned off
+// if a light is turned off, it won't activate emergency power
+/obj/machinery/light/proc/turned_off()
+	var/area/A = get_area(src)
+	return !A.lightswitch && A.power_light
 
 // returns whether this light has power
 // true if area has power and lightswitch is on
@@ -422,6 +512,27 @@
 	var/area/A = get_area(src)
 	return A.lightswitch && A.power_light
 
+// returns whether this light has emergency power
+// can also return if it has access to a certain amount of that power
+/obj/machinery/light/proc/has_emergency_power(pwr)
+	if(no_emergency || !cell)
+		return FALSE
+	if(pwr ? cell.charge >= pwr : cell.charge)
+		return status == LIGHT_OK
+
+// attempts to use power from the installed emergency cell, returns true if it does and false if it doesn't
+/obj/machinery/light/proc/use_emergency_power(pwr = 0.2)
+	if(!has_emergency_power(pwr))
+		return FALSE
+	if(cell.charge > 300) //it's meant to handle 120 W, ya doofus
+		visible_message("<span class='warning'>[src] short-circuits from too powerful of a power cell!</span>")
+		burn_out()
+		return FALSE
+	cell.use(pwr)
+	set_light(brightness * 0.25, max(0.5, 0.75 * (cell.charge / cell.maxcharge)), "#FF3232") //RGB: 255, 50, 50
+	return TRUE
+
+
 /obj/machinery/light/proc/flicker(var/amount = rand(10, 20))
 	set waitfor = 0
 	if(flickering)
@@ -441,7 +552,9 @@
 // ai attack - make lights flicker, because why not
 
 /obj/machinery/light/attack_ai(mob/user)
-	src.flicker(1)
+	no_emergency = !no_emergency
+	to_chat(user, "<span class='notice'>Emergency lights for this fixture have been [no_emergency ? "disabled" : "enabled"].</span>")
+	update(FALSE)
 	return
 
 // attack with hand - remove tube/bulb

code/modules/research/designs/autolathe_designs.dm

@@ -799,3 +799,11 @@
 	materials = list(MAT_METAL = 300, MAT_GLASS = 200)
 	build_path = /obj/item/device/slime_scanner
 	category = list("initial", "Misc")
+
+/datum/design/miniature_power_cell
+	name = "Light Fixture Battery"
+	id = "miniature_power_cell"
+	build_type = AUTOLATHE
+	materials = list(MAT_GLASS = 20)
+	build_path = /obj/item/stock_parts/cell/emergency_light
+	category = list("initial", "Electronics")