Adds wires for holopad (#89947)

## About The Pull Request
Adds wires for the holopad with a red light to turn recording on and off
and a purple one to switch the loop.

An example of a fun use with proximity sensor and looping switching:


https://github.com/user-attachments/assets/ad6a711a-3e10-4bfd-9b8c-ab83ca949f03

And a small piece showing what happens if you try to play a recording
without a disc or with an empty disc:



https://github.com/user-attachments/assets/9dd398d6-f189-4f65-b5e3-f53f2747398f
## Why It's Good For The Game
The holopad has great potential for personal constructions of players,
and I would like to expand its functionality by adding interaction with
the wiring.
## Changelog
🆑
add: Adds wires for holopad
/🆑

---------

Co-authored-by: grungussuss <96586172+Sadboysuss@users.noreply.github.com>
Co-authored-by: Ghom <42542238+Ghommie@users.noreply.github.com>

code/__DEFINES/wires.dm

@@ -95,6 +95,8 @@
 #define WIRE_OVERCLOCK "Overclock"
 #define WIRE_EQUIPMENT "Equipment"
 #define WIRE_ENVIRONMENT "Environment"
+#define WIRE_LOOP_MODE "Loop mode"
+#define WIRE_REPLAY_MODE "Replay mode"
 
 // Wire states for the AI
 #define AI_WIRE_NORMAL 0

code/datums/wires/holopad.dm

@@ -0,0 +1,47 @@
+/datum/wires/holopad
+	holder_type = /obj/machinery/holopad
+	proper_name = "holopad"
+
+/datum/wires/holopad/interactable(mob/user)
+	var/obj/machinery/holopad/holopad = holder
+
+	return holopad.panel_open ? ..() : FALSE
+
+/datum/wires/holopad/New(atom/holder)
+	wires = list(
+		WIRE_LOOP_MODE,
+		WIRE_REPLAY_MODE
+	)
+	return ..()
+
+/datum/wires/holopad/get_status()
+	var/obj/machinery/holopad/holopad = holder
+	var/list/status = list()
+	status += "The purple light is [holopad.loop_mode ? "on" : "off"]."
+	status += "The red light is [holopad.replay_mode ? "on" : "off"]."
+	return status
+
+/datum/wires/holopad/on_pulse(wire)
+	var/obj/machinery/holopad/holopad = holder
+	switch(wire)
+		if(WIRE_LOOP_MODE)
+			holopad.loop_mode = !holopad.loop_mode
+		if(WIRE_REPLAY_MODE)
+			if (!holopad.replay_mode)
+				holopad.replay_start()
+				holopad.replay_mode = TRUE
+			else
+				holopad.replay_stop()
+				holopad.replay_mode = FALSE
+	return ..()
+
+/datum/wires/holopad/on_cut(wire, mend, source)
+	var/obj/machinery/holopad/holopad = holder
+	if(wire == WIRE_REPLAY_MODE)
+		if(mend)
+			holopad.replay_stop()
+			holopad.replay_mode = FALSE
+		else
+			holopad.replay_start()
+			holopad.replay_mode = TRUE
+	return ..()

code/game/machinery/hologram.dm

@@ -108,6 +108,7 @@ Possible to do for anyone motivated enough:
 		)
 	)
 	AddElement(/datum/element/contextual_screentip_mob_typechecks, hovering_mob_typechecks)
+	set_wires(new /datum/wires/holopad(src))
 
 	if(on_network)
 		holopads += src
@@ -621,10 +622,12 @@ For the other part of the code, check silicon say.dm. Particularly robot talk.*/
 	return TRUE
 
 /obj/machinery/holopad/proc/clear_holo(datum/owner)
-	qdel(masters[owner]) // Get rid of owner's hologram
+	if(!disk || !disk.record)
+		return FALSE
+
+	qdel(masters[owner])
 	unset_holo(owner)
 	return TRUE
-
 /**
  * Called by holocall to inform outgoing_call that the receiver picked up.
  */
@@ -751,6 +754,14 @@ For the other part of the code, check silicon say.dm. Particularly robot talk.*/
 	return hologram
 
 /obj/machinery/holopad/proc/replay_start()
+	if(!disk)
+		say("Please insert the disc to play the recording.")
+		return
+
+	if(!disk.record)
+		say("There is no record on the disc. Please check the disk.")
+		return
+
 	if(!replay_mode)
 		replay_mode = TRUE
 		replay_holo = setup_replay_holo(disk.record)
@@ -758,6 +769,8 @@ For the other part of the code, check silicon say.dm. Particularly robot talk.*/
 		replay_entry(1)
 
 /obj/machinery/holopad/proc/replay_stop()
+	if(!disk || !disk.record)
+		return FALSE
 	if(replay_mode)
 		replay_mode = FALSE
 		offset = FALSE

tgstation.dme

@@ -2005,6 +2005,7 @@
 #include "code\datums\wires\emitter.dm"
 #include "code\datums\wires\explosive.dm"
 #include "code\datums\wires\fax.dm"
+#include "code\datums\wires\holopad.dm"
 #include "code\datums\wires\mass_driver.dm"
 #include "code\datums\wires\mecha.dm"
 #include "code\datums\wires\microwave.dm"