Refactors hud code, MASSIVELY improves Observe verb. (#657)

* pass hud into screen object new

* sanitize all screen object clicks

* robust observe

* fix action buttons and gunpoint

* fix skew

* fix radials and the crafting menu

* fix craft menu for real

* fix crafting 4 real

* use timer uses new format

* fix

code/_onclick/click.dm

@@ -353,9 +353,12 @@
 
 /atom/proc/ShiftClick(mob/user)
 	var/flags = SEND_SIGNAL(user, COMSIG_CLICK_SHIFT, src)
-	if(user.client && (user.client.eye == user || user.client.eye == user.loc || flags & COMPONENT_ALLOW_EXAMINATE))
-		user.examinate(src)
-	return
+	if(!user.client)
+		return
+	if(!((user.client.eye == user) || (user.client.eye == user.loc) || isobserver(user)) && !(flags & COMPONENT_ALLOW_EXAMINATE))
+		return
+
+	user.examinate(src)
 
 /**
  * Ctrl click
@@ -548,6 +551,10 @@
 	transform = M
 
 /atom/movable/screen/click_catcher/Click(location, control, params)
+	. = ..()
+	if(.)
+		return FALSE
+
 	var/list/modifiers = params2list(params)
 	if(LAZYACCESS(modifiers, MIDDLE_CLICK) && iscarbon(usr))
 		var/mob/living/carbon/C = usr

code/_onclick/hud/action_button.dm

@@ -1,7 +1,6 @@
 DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 /atom/movable/screen/movable/action_button
 	var/datum/action/linked_action
-	var/datum/hud/our_hud
 	var/actiontooltipstyle = ""
 	screen_loc = null
 
@@ -21,31 +20,30 @@ DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 	var/datum/weakref/last_hovored_ref
 
 /atom/movable/screen/movable/action_button/Destroy()
-	if(our_hud)
-		var/mob/viewer = our_hud.mymob
-		our_hud.hide_action(src)
+	if(hud)
+		var/mob/viewer = hud.mymob
+		hud.hide_action(src)
 		viewer?.client?.screen -= src
-		linked_action.viewers -= our_hud
+		linked_action.viewers -= hud
 		viewer.update_action_buttons()
-		our_hud = null
 	linked_action = null
 	return ..()
 
-/atom/movable/screen/movable/action_button/proc/can_use(mob/user)
+/atom/movable/screen/movable/action_button/can_usr_use(mob/user)
+	// Observers can only click on action buttons if they're not observing something
 	if(isobserver(user))
-		var/mob/dead/observer/dead_mob = user
-		if(dead_mob.observetarget) // Observers can only click on action buttons if they're not observing something
+		var/mob/dead/observer/O = user
+		if(O.observetarget)
 			return FALSE
 
 	if(linked_action)
 		if(linked_action.viewers[user.hud_used])
 			return TRUE
-		return FALSE
-
-	return TRUE
+	return FALSE
 
 /atom/movable/screen/movable/action_button/Click(location,control,params)
-	if (!can_use(usr))
+	. = ..()
+	if(.)
 		return FALSE
 
 	var/list/modifiers = params2list(params)
@@ -55,6 +53,7 @@ DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 		return TRUE
 	if(usr.next_click > world.time)
 		return
+
 	usr.next_click = world.time + 1
 	var/trigger_flags
 	if(LAZYACCESS(modifiers, RIGHT_CLICK))
@@ -66,7 +65,7 @@ DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 // Very much byond logic, but I want nice behavior, so we fake it with drag
 /atom/movable/screen/movable/action_button/MouseDrag(atom/over_object, src_location, over_location, src_control, over_control, params)
 	. = ..()
-	if(!can_use(usr))
+	if(!can_usr_use(usr))
 		return
 	if(IS_WEAKREF_OF(over_object, last_hovored_ref))
 		return
@@ -95,7 +94,7 @@ DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 
 /atom/movable/screen/movable/action_button/MouseDrop(over_object)
 	last_hovored_ref = null
-	if(!can_use(usr))
+	if(!can_usr_use(usr))
 		return
 	var/datum/hud/our_hud = usr.hud_used
 	if(over_object == src)
@@ -123,7 +122,7 @@ DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 	save_position()
 
 /atom/movable/screen/movable/action_button/proc/save_position()
-	var/mob/user = our_hud.mymob
+	var/mob/user = hud.mymob
 	if(!user?.client)
 		return
 	var/position_info = ""
@@ -138,14 +137,14 @@ DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 	user.client.prefs.action_buttons_screen_locs["[name]_[id]"] = position_info
 
 /atom/movable/screen/movable/action_button/proc/load_position()
-	var/mob/user = our_hud.mymob
+	var/mob/user = hud.mymob
 	if(!user)
 		return
 	var/position_info = user.client?.prefs?.action_buttons_screen_locs["[name]_[id]"] || SCRN_OBJ_DEFAULT
 	user.hud_used.position_action(src, position_info)
 
 /atom/movable/screen/movable/action_button/proc/dump_save()
-	var/mob/user = our_hud.mymob
+	var/mob/user = hud.mymob
 	if(!user?.client)
 		return
 	user.client.prefs.action_buttons_screen_locs -= "[name]_[id]"
@@ -253,12 +252,12 @@ DEFINE_INTERACTABLE(/atom/movable/screen/movable/action_button)
 
 /atom/movable/screen/button_palette/Destroy()
 	if(our_hud)
-		our_hud.mymob?.client?.screen -= src
+		our_hud.mymob?.canon_client?.screen -= src
 		our_hud.toggle_palette = null
 		our_hud = null
 	return ..()
 
-/atom/movable/screen/button_palette/Initialize(mapload)
+/atom/movable/screen/button_palette/Initialize(mapload, datum/hud/hud_owner)
 	. = ..()
 	update_appearance()
 
@@ -318,15 +317,10 @@ GLOBAL_LIST_INIT(palette_removed_matrix, list(1.4,0,0,0, 0.7,0.4,0,0, 0.4,0,0.6,
 	color_timer_id = null
 	remove_atom_colour(TEMPORARY_COLOUR_PRIORITY, to_remove)
 
-/atom/movable/screen/button_palette/proc/can_use(mob/user)
-	if (isobserver(user))
-		var/mob/dead/observer/O = user
-		return !O.observetarget
-	return TRUE
-
 /atom/movable/screen/button_palette/Click(location, control, params)
-	if(!can_use(usr))
-		return
+	. = ..()
+	if(.)
+		return FALSE
 
 	var/list/modifiers = params2list(params)
 
@@ -376,7 +370,8 @@ GLOBAL_LIST_INIT(palette_removed_matrix, list(1.4,0,0,0, 0.7,0.4,0,0, 0.4,0,0.6,
 	var/scroll_direction = 0
 	var/datum/hud/our_hud
 
-/atom/movable/screen/palette_scroll/proc/can_use(mob/user)
+/atom/movable/screen/palette_scroll/can_usr_use(mob/user)
+	. = ..()
 	if (isobserver(user))
 		var/mob/dead/observer/O = user
 		return !O.observetarget
@@ -395,8 +390,10 @@ GLOBAL_LIST_INIT(palette_removed_matrix, list(1.4,0,0,0, 0.7,0.4,0,0, 0.4,0,0.6,
 	icon = settings["bg_icon"]
 
 /atom/movable/screen/palette_scroll/Click(location, control, params)
-	if(!can_use(usr))
-		return
+	. = ..()
+	if(.)
+		return FALSE
+
 	our_hud.palette_actions.scroll(scroll_direction)
 
 /atom/movable/screen/palette_scroll/MouseEntered(location, control, params)
@@ -417,7 +414,7 @@ GLOBAL_LIST_INIT(palette_removed_matrix, list(1.4,0,0,0, 0.7,0.4,0,0, 0.4,0,0.6,
 
 /atom/movable/screen/palette_scroll/down/Destroy()
 	if(our_hud)
-		our_hud.mymob?.client?.screen -= src
+		our_hud.mymob?.canon_client?.screen -= src
 		our_hud.palette_down = null
 		our_hud = null
 	return ..()
@@ -430,7 +427,7 @@ GLOBAL_LIST_INIT(palette_removed_matrix, list(1.4,0,0,0, 0.7,0.4,0,0, 0.4,0,0.6,
 
 /atom/movable/screen/palette_scroll/up/Destroy()
 	if(our_hud)
-		our_hud.mymob?.client?.screen -= src
+		our_hud.mymob?.canon_client?.screen -= src
 		our_hud.palette_up = null
 		our_hud = null
 	return ..()
@@ -448,7 +445,7 @@ GLOBAL_LIST_INIT(palette_removed_matrix, list(1.4,0,0,0, 0.7,0.4,0,0, 0.4,0,0.6,
 /atom/movable/screen/action_landing/Destroy()
 	if(owner)
 		owner.landing = null
-		owner?.owner?.mymob?.client?.screen -= src
+		owner?.owner?.mymob?.canon_client?.screen -= src
 		owner.refresh_actions()
 		owner = null
 	return ..()

code/_onclick/hud/ai.dm

@@ -2,6 +2,10 @@
 	icon = 'icons/hud/screen_ai.dmi'
 
 /atom/movable/screen/ai/Click()
+	. = ..()
+	if(.)
+		return FALSE
+
 	if(isobserver(usr) || usr.incapacitated())
 		return TRUE
 
@@ -184,106 +188,89 @@
 	var/mob/living/silicon/ai/myai = mymob
 
 // Language menu
-	using = new /atom/movable/screen/language_menu
+	using = new /atom/movable/screen/language_menu(null, src)
 	using.screen_loc = ui_ai_language_menu
-	using.hud = src
 	static_inventory += using
 
 //AI core
-	using = new /atom/movable/screen/ai/aicore()
+	using = new /atom/movable/screen/ai/aicore(null, src)
 	using.screen_loc = ui_ai_core
-	using.hud = src
 	static_inventory += using
 
 //Camera list
-	using = new /atom/movable/screen/ai/camera_list()
+	using = new /atom/movable/screen/ai/camera_list(null, src)
 	using.screen_loc = ui_ai_camera_list
-	using.hud = src
 	static_inventory += using
 
 //Track
-	using = new /atom/movable/screen/ai/camera_track()
+	using = new /atom/movable/screen/ai/camera_track(null, src)
 	using.screen_loc = ui_ai_track_with_camera
-	using.hud = src
 	static_inventory += using
 
 //Camera light
-	using = new /atom/movable/screen/ai/camera_light()
+	using = new /atom/movable/screen/ai/camera_light(null, src)
 	using.screen_loc = ui_ai_camera_light
-	using.hud = src
 	static_inventory += using
 
 //Crew Monitoring
-	using = new /atom/movable/screen/ai/crew_monitor()
+	using = new /atom/movable/screen/ai/crew_monitor(null, src)
 	using.screen_loc = ui_ai_crew_monitor
-	using.hud = src
 	static_inventory += using
 
 //Crew Manifest
-	using = new /atom/movable/screen/ai/crew_manifest()
+	using = new /atom/movable/screen/ai/crew_manifest(null, src)
 	using.screen_loc = ui_ai_crew_manifest
-	using.hud = src
 	static_inventory += using
 
 //Alerts
-	using = new /atom/movable/screen/ai/alerts()
+	using = new /atom/movable/screen/ai/alerts(null, src)
 	using.screen_loc = ui_ai_alerts
-	using.hud = src
 	static_inventory += using
 
 //Announcement
-	using = new /atom/movable/screen/ai/announcement()
+	using = new /atom/movable/screen/ai/announcement(null, src)
 	using.screen_loc = ui_ai_announcement
-	using.hud = src
 	static_inventory += using
 
 //Shuttle
-	using = new /atom/movable/screen/ai/call_shuttle()
+	using = new /atom/movable/screen/ai/call_shuttle(null, src)
 	using.screen_loc = ui_ai_shuttle
-	using.hud = src
 	static_inventory += using
 
 //Laws
-	using = new /atom/movable/screen/ai/state_laws()
+	using = new /atom/movable/screen/ai/state_laws(null, src)
 	using.screen_loc = ui_ai_state_laws
-	using.hud = src
 	static_inventory += using
 
 // Modular Interface
-	using = new /atom/movable/screen/ai/modpc()
+	using = new /atom/movable/screen/ai/modpc(null, src)
 	using.screen_loc = ui_ai_mod_int
-	using.hud = src
 	static_inventory += using
 	myai.interfaceButton = using
 	var/atom/movable/screen/ai/modpc/tabletbutton = using
 	tabletbutton.robot = myai
 
 //Take image
-	using = new /atom/movable/screen/ai/image_take()
+	using = new /atom/movable/screen/ai/image_take(null, src)
 	using.screen_loc = ui_ai_take_picture
-	using.hud = src
 	static_inventory += using
 
 //View images
-	using = new /atom/movable/screen/ai/image_view()
+	using = new /atom/movable/screen/ai/image_view(null, src)
 	using.screen_loc = ui_ai_view_images
-	using.hud = src
 	static_inventory += using
 
 //Medical/Security sensors
-	using = new /atom/movable/screen/ai/sensors()
+	using = new /atom/movable/screen/ai/sensors(null, src)
 	using.screen_loc = ui_ai_sensor
-	using.hud = src
 	static_inventory += using
 
 //Multicamera mode
-	using = new /atom/movable/screen/ai/multicam()
+	using = new /atom/movable/screen/ai/multicam(null, src)
 	using.screen_loc = ui_ai_multicam
-	using.hud = src
 	static_inventory += using
 
 //Add multicamera camera
-	using = new /atom/movable/screen/ai/add_multicam()
+	using = new /atom/movable/screen/ai/add_multicam(null, src)
 	using.screen_loc = ui_ai_add_multicam
-	using.hud = src
 	static_inventory += using

code/_onclick/hud/alert.dm

@@ -109,6 +109,8 @@
 	/// Boolean. If TRUE, the Click() proc will attempt to Click() on the master first if there is a master.
 	var/click_master = TRUE
 
+/atom/movable/screen/alert/can_usr_use(mob/user)
+	return owner == usr
 
 /atom/movable/screen/alert/MouseEntered(location,control,params)
 	. = ..()
@@ -871,8 +873,10 @@ or shoot a gun to move around via Newton's 3rd Law of Motion."
 	return 1
 
 /atom/movable/screen/alert/Click(location, control, params)
-	if(!usr || !usr.client)
+	. = ..()
+	if(.)
 		return FALSE
+
 	if(usr != owner)
 		return FALSE
 	var/list/modifiers = params2list(params)