VRyHungry1/Net/net_pickable.gd

extends MultiplayerSynchronizer
#
### Networked sync component for a pickable item. Added as a child literally
### named "NetPickable" (network_manager.gd's authority RPCs already expect
### this) of every net-synced pickable, replicating its transform and held
### state. Only the current multiplayer authority (the server while loose, or
### whichever peer is holding it) actually simulates physics for the item;
### every other peer freezes their local copy and just follows the synced
### transform.
#
### 0 = loose/server-simulated; otherwise the peer id currently holding it.
### Replicated at spawn and on change so a late joiner sees the current holder.
#var net_held_by: int = 0: set = _set_net_held_by
#
#var _pickable: XRToolsPickable
#
## This item's own baked freeze_mode (e.g. plate.tscn bakes KINEMATIC, not the
## RigidBody3D default of STATIC) — captured once so it can be restored when
## this peer regains ownership, instead of getting stuck on whatever
## apply_held_state() last forced it to while non-authority.
#var _original_freeze_mode: int
#
## Same idea for the pickable's authored `enabled` flag, which the non-authority
## branch of apply_held_state() clears while someone else is holding the item.
#var _original_enabled: bool
#
## Whether the "our own hand still holds this" guard has already been logged for
## the current grab. apply_held_state() runs every network tick, so without this
## the guard message repeats for as long as you hold the item.
#var _grab_race_logged := false
#
#
#func _ready() -> void:
	#_pickable = get_parent() as XRToolsPickable
	#if not _pickable:
		#push_error("NetPickable must be a child of an XRToolsPickable")
		#return
	#_original_freeze_mode = _pickable.freeze_mode
	#_original_enabled = _pickable.enabled
	#_pickable.picked_up.connect(_on_picked_up)
	#_pickable.dropped.connect(_on_dropped)
	## Deferred: the pickable root captures its own original_collision_mask/
	## original_collision_layer via @onready, which runs AFTER this child's
	## _ready() but BEFORE the root's _ready() body. Calling apply_held_state
	## synchronously here would freeze/mask the item before that capture runs,
	## permanently corrupting the "restore on drop" values.
	#apply_held_state.call_deferred()
#
#
#func _set_net_held_by(value: int) -> void:
	#var old := net_held_by
	#net_held_by = value
	#if old != value and NetworkManager.is_online():
		#print("%s net_held_by: %d -> %d (local state: %s, authority=%d)" % [
			#_pickable.name, old, value, _holder_desc(), get_multiplayer_authority()
		#])
	#apply_held_state()
#
#
### Puts the item in the right physics state for whether this peer currently
### owns it. Called locally after net_held_by changes, and directly by
### NetworkManager._set_item_authority right after an authority handoff.
###
### IMPORTANT: this runs on every network tick, not just on a real change.
### net_held_by is replicated in ALWAYS mode, so the synchronizer assigns it every
### tick on non-authority peers — unchanged value included — and that assignment
### lands in _set_net_held_by(), which calls this. So every branch here has to be
### idempotent and silent when there is nothing to do: otherwise each item logs a
### line and rewrites four physics properties every tick on every peer that
### doesn't own it.
#func apply_held_state() -> void:
	#if not _pickable:
		#return
	#if not NetworkManager.is_online() or is_multiplayer_authority():
		#_grab_race_logged = false
		## We own this item's simulation (offline, loose+server, or currently
		## holding it). If it's not actively in our own hand right now, make
		## sure it isn't still left frozen/collision-less from a previous
		## non-authority period (e.g. right after regaining authority when a
		## client released it) — while actually held, XRToolsPickable's own
		## pick_up()/let_go() already manage these fields, so leave those be.
		#if not _pickable.is_picked_up():
			#var changed := _pickable.freeze_mode != _original_freeze_mode \
				#or _pickable.collision_mask != _pickable.original_collision_mask
			#if changed:
				#if NetworkManager.is_online():
					#print(
						#"%s: reclaiming ownership, restoring freeze_mode %d->%d collision_mask %d->%d" % [
							#_pickable.name, _pickable.freeze_mode, _original_freeze_mode,
							#_pickable.collision_mask, _pickable.original_collision_mask
						#]
					#)
				#_pickable.freeze_mode = _original_freeze_mode
				#_pickable.collision_mask = _pickable.original_collision_mask
		## Unlike freeze/collision (which XRToolsPickable manages itself while
		## held), `enabled` is only ever written by the non-authority branch
		## below, so it must be restored here or it stays false forever: once a
		## client grabbed this item, every other peer set enabled=false, and
		## regaining authority left it that way. On the server that silently
		## broke everything downstream — hands couldn't pick the item up again,
		## and a station snap zone would "snap" it (emitting has_picked_up, so
		## e.g. a plate still got marked dirty) while pick_up() bailed out on
		## the disabled item, leaving the zone holding an item with no grab
		## driver that then fell out of the station.
		#if _pickable.enabled != _original_enabled:
			#if NetworkManager.is_online():
				#print("%s: reclaiming ownership, restoring enabled %s->%s" % [
					#_pickable.name, _pickable.enabled, _original_enabled
				#])
			#_pickable.enabled = _original_enabled
		#return
	## A net_held_by/position sync update can race ahead of the
	## authority-handoff RPC that's about to confirm a grab we just made
	## optimistically (they travel on different channels with no ordering
	## guarantee). Don't let a stale sync value yank an item out of our own
	## hand mid-grab — only an explicit force_release_item rejection, or
	## actually losing authority for real, should end a grab we initiated.
	#if _pickable.is_picked_up() and _pickable.get_picked_up_by() is XRToolsFunctionPickup:
		## Log once per grab, not once per tick.
		#if NetworkManager.is_online() and not _grab_race_logged:
			#_grab_race_logged = true
			#print(
				#"%s: ignoring non-authority sync (net_held_by=%d) — still actively held by our own hand (grab-race guard)" % [
					#_pickable.name, net_held_by
				#]
			#)
		#return
	#_grab_race_logged = false
	## Someone else owns it: stop simulating locally, just follow the sync.
	#if _pickable.is_picked_up():
		#if NetworkManager.is_online():
			#print(
				#"%s: was held by %s on this peer, but authority now says peer %d owns it — force-dropping" % [
					#_pickable.name, _holder_desc(), net_held_by
				#]
			#)
		#_pickable.drop()
	## Bail out when we're already in the follow-the-sync state. Without this the
	## writes below (and the line logged with them) repeated every tick for every
	## item on every non-authority peer — 90% of the log, plus four redundant
	## physics-property writes per item per tick. The comparison also means we
	## still re-apply if something else perturbs the state (e.g. let_go()
	## restoring the collision mask after a force-drop).
	#var want_enabled := (net_held_by == 0)
	#if _pickable.freeze \
			#and _pickable.freeze_mode == RigidBody3D.FREEZE_MODE_KINEMATIC \
			#and _pickable.collision_mask == 0 \
			#and _pickable.enabled == want_enabled:
		#return
	#if NetworkManager.is_online():
		#print("%s: freezing (non-authority, owner=peer %d)" % [_pickable.name, net_held_by])
	#_pickable.freeze = true
	#_pickable.freeze_mode = RigidBody3D.FREEZE_MODE_KINEMATIC
	#_pickable.collision_mask = 0
	#_pickable.enabled = want_enabled
#
#
### Local hand grab (not a station snap zone, which is server-only): request
### authority immediately so the throw/drop can be reconciled, but let the grab
### happen instantly here rather than waiting on the round trip.
#func _on_picked_up(_p) -> void:
	#var by := _pickable.get_picked_up_by()
	#if not (by is XRToolsFunctionPickup):
		## e.g. a station snap zone grabbed it (server-side auto-snap, or the
		## addon's own "grab out of a snap zone" shortcut mid-cascade) — not a
		## player-initiated hand grab, so no authority request from here.
		#if NetworkManager.is_online():
			#print("%s picked up by %s (not a hand) — no authority request" % [_pickable.name, _holder_desc()])
		#return
	#if NetworkManager.is_online():
		#print("%s grabbed by hand (authority was peer %d), requesting authority" % [_pickable.name, net_held_by])
	#NetworkManager.request_item_authority_from(_pickable.get_path())
#
#
#func _on_dropped(_p) -> void:
	## Only forward if we're actually still the authority — a drop caused by
	## apply_held_state() losing authority (see above) must not re-report.
	#if not is_multiplayer_authority():
		#if NetworkManager.is_online():
			#print("%s dropped locally, but we aren't its authority (peer %d is) — not reporting" % [_pickable.name, net_held_by])
		#return
	#if NetworkManager.is_online():
		#print("%s dropped, reporting release to server (lin=%s ang=%s)" % [
			#_pickable.name, _pickable.linear_velocity, _pickable.angular_velocity
		#])
	## Send our own final transform too: we were the authority until now, and the
	## server's copy may not have received our last position sync yet.
	#NetworkManager.release_item_authority_from(
		#_pickable.get_path(), _pickable.linear_velocity, _pickable.angular_velocity,
		#_pickable.global_transform
	#)
#
#
### Human-readable description of what's currently holding this item on THIS
### peer, for diagnosing desyncs between a hand's own "what am I holding"
### bookkeeping and the item's actual grab state (see the snap-zone-grab race
### in NetworkManager._try_snap_into_station for a real example).
#func _holder_desc() -> String:
	#if not _pickable or not _pickable.is_picked_up():
		#return "loose"
	#var by := _pickable.get_picked_up_by()
	#if not by:
		#return "held(no grabber?)"
	#if by is XRToolsFunctionPickup:
		#return "hand(%s)" % by.get_path()
	#if by is XRToolsSnapZone:
		#var station := by.get_parent()
		#return "zone(%s)" % (station.name if station else str(by.get_path()))
	#return "other(%s: %s)" % [by.get_class(), by.get_path()]