straywild/network/network_home_service.gd

class_name NetworkHomeService
extends Node

const NetworkHomeProtocolType = preload(
	"res://network/network_home_protocol.gd"
)
const PlayerHomeStateType = preload("res://homes/player_home_state.gd")
const DecorCatalogType = preload("res://homes/decor_catalog.gd")
const OwnedItemType = preload("res://items/owned_item.gd")

signal local_transition_finished(accepted: bool, message: String)
signal local_space_changed(space_id: StringName, owner_fingerprint: String)
signal local_manifest_rejected(message: String)

const MAX_MANIFESTS: int = 128
const MAX_PENDING_LOCAL_DECOR_TRANSACTIONS: int = 16

var _session: NetworkSession
var _spawn_service: PlayerSpawnService
var _local_home: PlayerHomeStateType
var _save_manager: PlayerSaveManager
var _world_service: HomeWorldService
var _bag: PlayerBag
var _inventory_layout: PlayerInventoryLayout
var _hotbar: PlayerHotbar
var _manifests_by_fingerprint: Dictionary[String, Dictionary] = {}
var _fingerprint_by_peer: Dictionary[int, String] = {}
var _authorized_owned_counts: Dictionary[int, Dictionary] = {}
var _authorization_result_owner: Dictionary[String, int] = {}
var _interior_slots_by_space: Dictionary[StringName, Dictionary] = {}
var _next_interior_index: int = 0
var _suppress_local_submission: bool = false
var _publish_queued: bool = false
var _last_submitted_local_home_revision: int = -1
var _pending_local_decor_transactions: Dictionary[int, Dictionary] = {}


func setup(
	session: NetworkSession,
	spawn_service: PlayerSpawnService,
	local_home: PlayerHomeStateType,
	save_manager: PlayerSaveManager,
	world_service: HomeWorldService,
	bag: PlayerBag,
	inventory_layout: PlayerInventoryLayout,
	hotbar: PlayerHotbar,
) -> void:
	_session = session
	_spawn_service = spawn_service
	_local_home = local_home
	_save_manager = save_manager
	_world_service = world_service
	_bag = bag
	_inventory_layout = inventory_layout
	_hotbar = hotbar
	if not _session.state_changed.is_connected(_on_session_state_changed):
		_session.state_changed.connect(_on_session_state_changed)
	if not _session.join_authenticated.is_connected(_on_join_authenticated):
		_session.join_authenticated.connect(_on_join_authenticated)
	if not _session.peer_authenticated.is_connected(_on_peer_authenticated):
		_session.peer_authenticated.connect(_on_peer_authenticated)
	if not _session.peer_removed.is_connected(_on_peer_removed):
		_session.peer_removed.connect(_on_peer_removed)
	if not _local_home.changed.is_connected(_on_local_home_changed):
		_local_home.changed.connect(_on_local_home_changed)


func get_local_space() -> StringName:
	if _session == null or not _session.is_gameplay_session_active():
		return NetworkHomeProtocolType.WORLD_SPACE
	return _session.get_peer_space(_session.get_local_peer_id())


func get_local_home_owner_fingerprint() -> String:
	var space_id: String = String(get_local_space())
	return space_id.trim_prefix("rv:") if space_id.begins_with("rv:") else ""


func can_local_decorate() -> bool:
	return (
		get_local_home_owner_fingerprint()
		== _session.get_local_identity_fingerprint()
	)


func has_pending_local_decor_mutation() -> bool:
	return not _pending_local_decor_transactions.is_empty()


func get_authoritative_owned_count(
	peer_id: int,
	decor_id: StringName,
) -> int:
	var authorized: Dictionary = _authorized_owned_counts.get(peer_id, {})
	if authorized.has(String(decor_id)):
		return int(authorized[String(decor_id)])
	var fingerprint: String = _fingerprint_for_peer(peer_id)
	var manifest: Dictionary = _manifests_by_fingerprint.get(fingerprint, {})
	if manifest.is_empty():
		return -1
	var home: Dictionary = manifest.get("home", {})
	var owned: Dictionary = home.get("owned_decor", {})
	return int(owned.get(String(decor_id), 0))


func place_local_decor(
	decor_id: StringName,
	position: Vector3,
	yaw_radians: float,
	mode: PlayerHomeStateType.PlacementMode,
) -> String:
	if (
		not can_local_decorate()
		or has_pending_local_decor_mutation()
		or _bag == null
		or _bag.get_quantity(decor_id) <= 0
		or _world_service == null
	):
		return ""
	var owner_fingerprint: String = (
		_session.get_local_identity_fingerprint()
	)
	var normalized: Dictionary = (
		_local_home.get_nearest_valid_placement_transform(
			decor_id,
			position,
			yaw_radians,
			mode,
			"",
			Callable(
				self, "_candidate_clear_of_players"
			).bind(owner_fingerprint, decor_id),
		)
	)
	if normalized.is_empty():
		return ""
	var transaction: Dictionary = _capture_local_decor_transaction()
	if transaction.is_empty():
		return ""
	_suppress_local_submission = true
	var instance_id: String = _local_home.place_decor(
		decor_id,
		normalized["position"],
		float(normalized["yaw"]),
		mode,
	)
	if instance_id.is_empty():
		_suppress_local_submission = false
		return ""
	if not _bag.remove_item(decor_id, 1):
		_local_home.remove_placement(instance_id)
		_suppress_local_submission = false
		return ""
	_suppress_local_submission = false
	if not _commit_local_decor_transaction(transaction):
		return ""
	return instance_id


func remove_local_decor(instance_id: String) -> bool:
	if (
		not can_local_decorate()
		or has_pending_local_decor_mutation()
		or _bag == null
		or _inventory_layout == null
		or _hotbar == null
	):
		return false
	var placement: Dictionary = _local_home.get_placement(instance_id)
	if placement.is_empty():
		return false
	var transaction: Dictionary = _capture_local_decor_transaction()
	if transaction.is_empty():
		return false
	var decor_id := StringName(str(placement["decor_id"]))
	var target_hotbar_slot: int = _hotbar.find_item_slot(decor_id)
	if target_hotbar_slot < 0:
		target_hotbar_slot = _hotbar.find_first_empty_slot()
	var prepared_hotbar_placement: bool = false
	if (
		target_hotbar_slot >= 0
		and _inventory_layout.get_container(
			PlayerInventoryLayout.EntryKind.ITEM,
			decor_id,
		) < 0
	):
		prepared_hotbar_placement = (
			_inventory_layout.prepare_new_item_placement(
				decor_id,
				PlayerInventoryLayout.InventoryContainer.HOTBAR,
				target_hotbar_slot,
			)
		)
	var returned_to_inventory: bool = _bag.add_item(decor_id, 1)
	if not returned_to_inventory:
		if prepared_hotbar_placement:
			_inventory_layout.cancel_prepared_item_placement(decor_id)
		returned_to_inventory = _bag.add_item_to_storage(decor_id, 1)
	if not returned_to_inventory:
		if prepared_hotbar_placement:
			_inventory_layout.cancel_prepared_item_placement(decor_id)
		return false
	if target_hotbar_slot >= 0:
		_hotbar.assign_item(target_hotbar_slot, decor_id)
		_hotbar.select_slot(target_hotbar_slot)
	_suppress_local_submission = true
	if not _local_home.remove_placement(instance_id):
		_suppress_local_submission = false
		_restore_local_decor_transaction(transaction)
		return false
	_suppress_local_submission = false
	if not _commit_local_decor_transaction(transaction):
		return false
	return true


func update_local_decor(
	instance_id: String,
	position: Vector3,
	yaw_radians: float,
	mode: PlayerHomeStateType.PlacementMode,
) -> bool:
	if has_pending_local_decor_mutation():
		return false
	var normalized: Dictionary = get_valid_local_decor_transform(
		instance_id, position, yaw_radians, mode
	)
	if normalized.is_empty():
		return false
	var transaction: Dictionary = _capture_local_decor_transaction()
	if transaction.is_empty():
		return false
	_suppress_local_submission = true
	if not _local_home.update_placement(
		instance_id,
		normalized["position"],
		float(normalized["yaw"]),
		mode,
	):
		_suppress_local_submission = false
		return false
	_suppress_local_submission = false
	if not _commit_local_decor_transaction(transaction):
		return false
	return true


func get_valid_local_decor_transform(
	instance_id: String,
	position: Vector3,
	yaw_radians: float,
	mode: PlayerHomeStateType.PlacementMode,
) -> Dictionary:
	if not can_local_decorate() or _world_service == null:
		return {}
	var placement: Dictionary = _local_home.get_placement(instance_id)
	if placement.is_empty():
		return {}
	var decor_id := StringName(str(placement.get("decor_id", "")))
	return _local_home.get_valid_update_transform(
		instance_id,
		position,
		yaw_radians,
		mode,
		Callable(
			self, "_candidate_clear_of_players"
		).bind(
			_session.get_local_identity_fingerprint(), decor_id
		),
	)


func _candidate_clear_of_players(
	candidate: Dictionary,
	owner_fingerprint: String,
	decor_id: StringName,
) -> bool:
	return (
		_world_service != null
		and _world_service.is_decor_placement_clear_of_players(
			owner_fingerprint,
			decor_id,
			candidate["position"],
			float(candidate["yaw"]),
		)
	)


func request_enter(owner_fingerprint: String) -> bool:
	if (
		_session == null
		or not _session.is_gameplay_session_active()
		or not _manifests_by_fingerprint.has(owner_fingerprint)
		or get_local_space() != NetworkHomeProtocolType.WORLD_SPACE
	):
		return false
	return _submit_transition(
		NetworkHomeProtocolType.TransitionAction.ENTER,
		owner_fingerprint,
	)


func request_exit() -> bool:
	var owner_fingerprint: String = get_local_home_owner_fingerprint()
	if owner_fingerprint.is_empty():
		return false
	return _submit_transition(
		NetworkHomeProtocolType.TransitionAction.EXIT,
		owner_fingerprint,
	)


func authorize_decor_purchase(
	peer_id: int,
	product_id: StringName,
	resulting_count: int,
	result_id: String,
) -> void:
	if not _session.is_host() or peer_id <= 0 or result_id.is_empty():
		return
	var counts: Dictionary = _authorized_owned_counts.get(peer_id, {})
	counts[String(product_id)] = resulting_count
	_authorized_owned_counts[peer_id] = counts
	_authorization_result_owner[result_id] = peer_id


func finalize_decor_purchase(
	peer_id: int,
	result_id: String,
	applied: bool,
) -> void:
	if _authorization_result_owner.get(result_id, 0) != peer_id:
		return
	_authorization_result_owner.erase(result_id)
	if applied:
		return
	_authorized_owned_counts.erase(peer_id)


func refresh_world_presentations() -> void:
	if _world_service == null:
		return
	_world_service.clear_presentations()
	if not _world_service.is_world_ready():
		return
	if not _session.is_host():
		for manifest: Dictionary in _manifests_by_fingerprint.values():
			_world_service.apply_manifest(manifest)
		return
	var local_fingerprint: String = _session.get_local_identity_fingerprint()
	if (
		not _session.is_dedicated_host()
		and not _manifests_by_fingerprint.has(local_fingerprint)
	):
		publish_local_home()
	var fingerprints: Array[String] = []
	fingerprints.assign(_manifests_by_fingerprint.keys())
	fingerprints.sort()
	var reserved: Array[Transform3D] = []
	for fingerprint: String in fingerprints:
		var manifest: Dictionary = _manifests_by_fingerprint[fingerprint]
		var transform: Transform3D = _world_service.choose_exterior_transform(
			int(manifest["owner_peer_id"]), reserved
		)
		reserved.append(transform)
		manifest["exterior_transform"] = (
			NetworkHomeProtocolType.transform_to_array(transform)
		)
		_manifests_by_fingerprint[fingerprint] = manifest
		_broadcast_manifest(manifest)
	for fingerprint: String in fingerprints:
		var manifest: Dictionary = _manifests_by_fingerprint[fingerprint]
		_spawn_peer_at_exterior(
			int(manifest["owner_peer_id"]), fingerprint
		)


func publish_local_home(
	allow_pending_decor_transaction: bool = false,
) -> bool:
	if (
		_session == null
		or not _session.is_gameplay_session_active()
		or _session.is_dedicated_host()
		or _local_home == null
	):
		return false
	# A purchase can update the owned decor count while an optimistic placement
	# is waiting on the host. Hold that follow-up manifest until the placement is
	# accepted or rolled back; otherwise it can carry the still-unverified
	# placement and turn one rejection into a second stale rejection.
	if (
		not allow_pending_decor_transaction
		and has_pending_local_decor_mutation()
	):
		_publish_queued = true
		return true
	if _session.is_host() and (
		_world_service == null or not _world_service.is_world_ready()
	):
		return false
	var home_data: Dictionary = _local_home.to_save_data()
	var revision: int = int(home_data.get("revision", -1))
	if revision >= 0 and revision == _last_submitted_local_home_revision:
		return true
	var request: Dictionary = {
		"request_id": _new_id("home"),
		"session_id": _session.get_session_id(),
		"owner_fingerprint": _session.get_local_identity_fingerprint(),
		"home": home_data,
		"digest": NetworkHomeProtocolType.manifest_digest(home_data),
	}
	request["sender_signature"] = _session.sign_local_action(
		"portable_home_manifest",
		NetworkHomeProtocolType.manifest_signature_fields(request),
	)
	_last_submitted_local_home_revision = revision
	if _session.is_host():
		_process_manifest_request(_session.get_local_peer_id(), request)
	else:
		submit_home_manifest.rpc_id(1, request)
	return true


@rpc(
	"any_peer", "call_remote", "reliable",
	NetworkHomeProtocolType.RELIABLE_CHANNEL,
)
func submit_home_manifest(data: Dictionary) -> void:
	var sender_id: int = multiplayer.get_remote_sender_id()
	if (
		_session == null
		or not _session.is_host()
		or not _session.is_authenticated_peer(sender_id)
	):
		return
	_process_manifest_request(sender_id, data)


func _process_manifest_request(peer_id: int, data: Dictionary) -> void:
	if (
		not NetworkHomeProtocolType.validate_manifest_request(data)
		or str(data["session_id"]) != _session.get_session_id()
	):
		_reject_manifest(peer_id, "The RV update was invalid.")
		return
	var record := _session.get_peer_record(peer_id)
	var fingerprint: String = str(data["owner_fingerprint"])
	if (
		record == null
		or record.identity_fingerprint != fingerprint
		or not _session.verify_peer_action(
			peer_id,
			"portable_home_manifest",
			NetworkHomeProtocolType.manifest_signature_fields(data),
			data["sender_signature"],
		)
	):
		_reject_manifest(peer_id, "The RV owner could not be verified.")
		return
	var home_data: Dictionary = PlayerHomeStateType.sanitize_save_data(
		data["home"]
	)
	var prior: Dictionary = _manifests_by_fingerprint.get(fingerprint, {})
	var is_first_manifest: bool = prior.is_empty()
	if not _valid_manifest_revision(peer_id, prior, home_data):
		_reject_manifest(peer_id, "The RV update was rejected by the host.")
		return
	if not _moved_decor_clear_of_players(fingerprint, prior, home_data):
		_reject_manifest(peer_id, "A player is in the way of that decor.")
		return
	var manifest: Dictionary
	if prior.is_empty():
		if _manifests_by_fingerprint.size() >= MAX_MANIFESTS:
			_reject_manifest(peer_id, "This room cannot place another RV.")
			return
		var reserved: Array[Transform3D] = []
		for existing: Dictionary in _manifests_by_fingerprint.values():
			reserved.append(NetworkHomeProtocolType.array_to_transform(
				existing["exterior_transform"]
			))
		var exterior_transform: Transform3D = (
			_world_service.choose_exterior_transform(peer_id, reserved)
		)
		manifest = {
			"owner_peer_id": peer_id,
			"owner_fingerprint": fingerprint,
			"home": home_data,
			"exterior_transform": (
				NetworkHomeProtocolType.transform_to_array(exterior_transform)
			),
			"interior_index": _next_interior_index,
		}
		_next_interior_index += 1
	else:
		manifest = prior.duplicate(true)
		manifest["home"] = home_data
		manifest["owner_peer_id"] = peer_id
	_manifests_by_fingerprint[fingerprint] = manifest
	_fingerprint_by_peer[peer_id] = fingerprint
	_consume_owned_authorizations(peer_id, home_data)
	if peer_id == _session.get_local_peer_id():
		_discard_local_decor_transactions_through(
			int(home_data.get("revision", -1))
		)
		if _last_submitted_local_home_revision == int(
			home_data.get("revision", -1)
		):
			_last_submitted_local_home_revision = -1
		_flush_queued_local_home_publish()
	_broadcast_manifest(manifest)
	if is_first_manifest:
		_spawn_peer_at_exterior(peer_id, fingerprint)


func _valid_manifest_revision(
	peer_id: int,
	prior_manifest: Dictionary,
	home_data: Dictionary,
) -> bool:
	if prior_manifest.is_empty():
		# A portable RV is owned by the player's signed local save. A new host has
		# no prior room ledger with which to compare its first manifest.
		return true
	var prior_home: Dictionary = prior_manifest["home"]
	if (
		int(home_data["revision"]) <= int(prior_home["revision"])
		or int(home_data["tier"]) != int(prior_home["tier"])
		or str(home_data["exterior_id"]) != str(prior_home["exterior_id"])
	):
		return false
	var prior_owned: Dictionary = prior_home["owned_decor"]
	var next_owned: Dictionary = home_data["owned_decor"]
	var all_ids: Dictionary[String, bool] = {}
	for value: Variant in prior_owned.keys():
		all_ids[str(value)] = true
	for value: Variant in next_owned.keys():
		all_ids[str(value)] = true
	var authorized: Dictionary = _authorized_owned_counts.get(peer_id, {})
	for product_id: String in all_ids:
		var prior_count: int = int(prior_owned.get(product_id, 0))
		var next_count: int = int(next_owned.get(product_id, 0))
		if prior_count == next_count:
			continue
		if next_count < prior_count or int(authorized.get(product_id, -1)) != next_count:
			return false
	return true


func _moved_decor_clear_of_players(
	owner_fingerprint: String,
	prior_manifest: Dictionary,
	home_data: Dictionary,
) -> bool:
	if _world_service == null:
		return false
	var prior_by_instance: Dictionary[String, Dictionary] = {}
	if not prior_manifest.is_empty():
		var prior_home: Dictionary = prior_manifest.get("home", {})
		for value: Variant in prior_home.get("placements", []):
			if typeof(value) != TYPE_DICTIONARY:
				continue
			var prior_placement: Dictionary = value
			prior_by_instance[str(
				prior_placement.get("instance_id", "")
			)] = prior_placement
	for value: Variant in home_data.get("placements", []):
		if typeof(value) != TYPE_DICTIONARY:
			return false
		var placement: Dictionary = value
		var instance_id: String = str(placement.get("instance_id", ""))
		var prior_placement: Dictionary = prior_by_instance.get(
			instance_id, {}
		)
		if (
			not prior_placement.is_empty()
			and _same_decor_transform(prior_placement, placement)
		):
			continue
		var decor_id := StringName(str(placement.get("decor_id", "")))
		var position: Vector3 = _placement_position(placement)
		if (
			not position.is_finite()
			or not _world_service.is_decor_placement_clear_of_players(
				owner_fingerprint,
				decor_id,
				position,
				float(placement.get("yaw", 0.0)),
			)
		):
			return false
	return true


static func _same_decor_transform(
	first: Dictionary,
	second: Dictionary,
) -> bool:
	if str(first.get("decor_id", "")) != str(second.get("decor_id", "")):
		return false
	var first_position: Vector3 = _placement_position(first)
	var second_position: Vector3 = _placement_position(second)
	return (
		first_position.is_equal_approx(second_position)
		and is_equal_approx(
			float(first.get("yaw", 0.0)),
			float(second.get("yaw", 0.0)),
		)
	)


static func _placement_position(placement: Dictionary) -> Vector3:
	var values: Array = placement.get("position", [])
	if values.size() != 3:
		return Vector3.INF
	return Vector3(
		float(values[0]), float(values[1]), float(values[2])
	)


func _consume_owned_authorizations(peer_id: int, home_data: Dictionary) -> void:
	var authorized: Dictionary = _authorized_owned_counts.get(peer_id, {})
	if authorized.is_empty():
		return
	var owned: Dictionary = home_data["owned_decor"]
	for product_id: String in authorized.keys():
		if int(owned.get(product_id, -1)) == int(authorized[product_id]):
			authorized.erase(product_id)
	if authorized.is_empty():
		_authorized_owned_counts.erase(peer_id)
	else:
		_authorized_owned_counts[peer_id] = authorized


func _broadcast_manifest(manifest: Dictionary) -> void:
	if _world_service != null and _world_service.is_world_ready():
		_world_service.apply_manifest(manifest)
	for peer_id: int in _session.get_authenticated_peer_ids():
		if peer_id == 1:
			continue
		receive_home_manifest.rpc_id(peer_id, manifest)


@rpc(
	"authority", "call_remote", "reliable",
	NetworkHomeProtocolType.RELIABLE_CHANNEL,
)
func receive_home_manifest(data: Dictionary) -> void:
	if not NetworkHomeProtocolType.validate_manifest_broadcast(data):
		return
	var fingerprint: String = str(data["owner_fingerprint"])
	_manifests_by_fingerprint[fingerprint] = data.duplicate(true)
	_fingerprint_by_peer[int(data["owner_peer_id"])] = fingerprint
	if fingerprint == _session.get_local_identity_fingerprint():
		var home: Dictionary = data.get("home", {})
		_discard_local_decor_transactions_through(
			int(home.get("revision", -1))
		)
		if _last_submitted_local_home_revision == int(
			home.get("revision", -1)
		):
			_last_submitted_local_home_revision = -1
		_flush_queued_local_home_publish()
	if _world_service != null and _world_service.is_world_ready():
		_world_service.apply_manifest(data)


func _reject_manifest(peer_id: int, message: String) -> void:
	var fingerprint: String = _fingerprint_for_peer(peer_id)
	var canonical: Dictionary = _manifests_by_fingerprint.get(fingerprint, {})
	if peer_id == _session.get_local_peer_id():
		_apply_manifest_rejection(message, canonical)
	else:
		receive_home_manifest_rejection.rpc_id(peer_id, message, canonical)


@rpc(
	"authority", "call_remote", "reliable",
	NetworkHomeProtocolType.RELIABLE_CHANNEL,
)
func receive_home_manifest_rejection(
	message: String,
	canonical: Dictionary,
) -> void:
	_apply_manifest_rejection(message, canonical)


func _apply_manifest_rejection(message: String, canonical: Dictionary) -> void:
	_last_submitted_local_home_revision = -1
	var canonical_home: Dictionary = canonical.get("home", {})
	var canonical_revision: int = int(canonical_home.get("revision", -1))
	var transaction: Dictionary = _get_local_decor_rejection_transaction(
		canonical_revision
	)
	if canonical.is_empty() or not NetworkHomeProtocolType.validate_manifest_broadcast(canonical):
		if not transaction.is_empty():
			_restore_local_decor_transaction(transaction)
			_pending_local_decor_transactions.clear()
			if _save_manager != null and not _save_manager.save_if_dirty():
				push_warning("Unable to save the restored RV decor state.")
		_flush_queued_local_home_publish()
		local_manifest_rejected.emit(message)
		return
	# A shop result can be accepted locally while its own home manifest is still
	# in flight. A delayed rejection for an earlier placement must not erase that
	# accepted purchase just because the host's canonical manifest predates it.
	var locally_owned_decor: Dictionary[StringName, int] = (
		_capture_local_owned_decor_counts()
	)
	# Only carry ownership forward across an actual pending decor-action
	# rejection. A standalone rejected manifest must remain authoritative rather
	# than repeatedly re-submitting an unverified owned-count increase.
	var has_owned_decor_increase: bool = (
		not transaction.is_empty()
		and _has_local_owned_decor_increase(
			locally_owned_decor,
			canonical_home,
		)
	)
	_suppress_local_submission = true
	var restored: bool = _local_home.restore_from_save_data(canonical_home)
	var owned_decor_restored: bool = (
		restored
		and (
			not has_owned_decor_increase
			or _restore_local_owned_decor_increases(locally_owned_decor)
		)
	)
	var reconciled: bool = (
		restored
		and owned_decor_restored
		and _reconcile_local_decor_inventory(transaction)
	)
	_suppress_local_submission = false
	_discard_local_decor_transactions_after(canonical_revision)
	if not reconciled:
		push_error("Unable to reconcile RV decor after a host rejection.")
	elif _save_manager != null and not _save_manager.save_if_dirty():
		push_warning("Unable to save the restored RV decor state.")
	receive_home_manifest(canonical)
	if reconciled and has_owned_decor_increase:
		# Submit the preserved purchase as a fresh revision after applying the
		# canonical placement rollback. This is deliberately separate from the
		# rejected action, so the host can validate the already-authorized count.
		if not publish_local_home():
			push_warning("Unable to publish the restored RV decor ownership.")
	local_manifest_rejected.emit(message)


func _capture_local_decor_transaction() -> Dictionary:
	if (
		_local_home == null
		or _bag == null
		or _inventory_layout == null
		or _hotbar == null
	):
		return {}
	var saved_items: Array[OwnedItemType] = []
	for item: OwnedItemType in _bag.get_all_items():
		saved_items.append(item.duplicate_record())
	return {
		"home": _local_home.to_save_data(),
		"bag_items": saved_items,
		"layout": _inventory_layout.to_save_data(),
		"hotbar_slots": _hotbar.get_slots(),
		"hotbar_fish_slots": _hotbar.get_fish_slots(),
		"selected_hotbar_slot": _hotbar.get_selected_slot(),
	}


func _capture_local_owned_decor_counts() -> Dictionary[StringName, int]:
	var counts: Dictionary[StringName, int] = {}
	if _local_home == null:
		return counts
	for decor_id: StringName in DecorCatalogType.get_product_ids():
		counts[decor_id] = _local_home.get_owned_count(decor_id)
	return counts


func _has_local_owned_decor_increase(
	local_counts: Dictionary[StringName, int],
	canonical_home: Dictionary,
) -> bool:
	var canonical_owned: Dictionary = canonical_home.get("owned_decor", {})
	for decor_id: StringName in DecorCatalogType.get_product_ids():
		if int(local_counts.get(decor_id, 0)) > int(
			canonical_owned.get(String(decor_id), 0)
		):
			return true
	return false


func _restore_local_owned_decor_increases(
	local_counts: Dictionary[StringName, int],
) -> bool:
	if _local_home == null:
		return false
	for decor_id: StringName in DecorCatalogType.get_product_ids():
		var local_count: int = int(local_counts.get(decor_id, 0))
		var canonical_count: int = _local_home.get_owned_count(decor_id)
		while canonical_count < local_count:
			if not _local_home.add_owned_decor(decor_id, 1):
				return false
			canonical_count += 1
	return true


func _commit_local_decor_transaction(transaction: Dictionary) -> bool:
	if _save_manager == null or not _save_manager.save_if_dirty():
		_restore_local_decor_transaction(transaction)
		return false
	var revision: int = _local_home.get_revision()
	_pending_local_decor_transactions[revision] = transaction.duplicate(true)
	_trim_pending_local_decor_transactions()
	if publish_local_home(true):
		return true
	_pending_local_decor_transactions.erase(revision)
	_restore_local_decor_transaction(transaction)
	_flush_queued_local_home_publish()
	# The optimistic mutation was already written before we attempted to publish
	# it. If the session ended or could not accept the manifest, immediately
	# persist the restored state so a restart cannot resurrect the rejected
	# placement or consume its decor item.
	if _save_manager != null and not _save_manager.save_if_dirty():
		push_warning("Unable to save the restored RV decor state.")
	return false


func _restore_local_decor_transaction(transaction: Dictionary) -> bool:
	if (
		transaction.is_empty()
		or _local_home == null
		or _bag == null
		or _inventory_layout == null
		or _hotbar == null
	):
		return false
	var home_data: Variant = transaction.get("home", {})
	var layout_data: Variant = transaction.get("layout", {})
	var stored_items: Variant = transaction.get("bag_items", [])
	var stored_slots: Variant = transaction.get("hotbar_slots", [])
	var stored_fish_slots: Variant = transaction.get("hotbar_fish_slots", [])
	if (
		typeof(home_data) != TYPE_DICTIONARY
		or typeof(layout_data) != TYPE_DICTIONARY
		or typeof(stored_items) != TYPE_ARRAY
		or typeof(stored_slots) != TYPE_ARRAY
		or typeof(stored_fish_slots) != TYPE_ARRAY
	):
		return false
	var items: Array[OwnedItemType] = []
	for value: Variant in stored_items as Array:
		if not value is OwnedItemType:
			return false
		items.append((value as OwnedItemType).duplicate_record())
	var slots: Array[StringName] = []
	for value: Variant in stored_slots as Array:
		slots.append(StringName(str(value)))
	var fish_slots: Array[StringName] = []
	for value: Variant in stored_fish_slots as Array:
		fish_slots.append(StringName(str(value)))
	var was_suppressed: bool = _suppress_local_submission
	_suppress_local_submission = true
	var home_restored: bool = _local_home.restore_from_save_data(
		home_data as Dictionary
	)
	var bag_restored: bool = _bag.replace_all_items(items)
	var layout_restored: bool = _inventory_layout.restore_from_save_data(
		layout_data as Dictionary
	)
	var hotbar_restored: bool = _hotbar.replace_state(
		slots,
		int(transaction.get("selected_hotbar_slot", 0)),
		fish_slots,
		false,
	)
	_suppress_local_submission = was_suppressed
	return home_restored and bag_restored and layout_restored and hotbar_restored


func _reconcile_local_decor_inventory(transaction: Dictionary) -> bool:
	if _bag == null or _local_home == null:
		return false
	var preferred_slots: Dictionary[StringName, int] = (
		_decor_hotbar_slots_from_transaction(transaction)
	)
	for decor_id: StringName in DecorCatalogType.get_product_ids():
		var target_quantity: int = _local_home.get_available_count(decor_id)
		var current_quantity: int = _bag.get_quantity(decor_id)
		if current_quantity > target_quantity:
			if not _bag.remove_item(
				decor_id, current_quantity - target_quantity
			):
				return false
			continue
		while current_quantity < target_quantity:
			var preferred_slot: int = int(
				preferred_slots.get(decor_id, -1)
			)
			if not _restore_decor_item_to_bag(decor_id, preferred_slot):
				return false
			current_quantity += 1
	return true


func _decor_hotbar_slots_from_transaction(
	transaction: Dictionary,
) -> Dictionary[StringName, int]:
	var result: Dictionary[StringName, int] = {}
	var stored_slots: Variant = transaction.get("hotbar_slots", [])
	if typeof(stored_slots) != TYPE_ARRAY:
		return result
	for slot_index: int in range((stored_slots as Array).size()):
		var decor_id := StringName(str((stored_slots as Array)[slot_index]))
		if DecorCatalogType.has_product(decor_id):
			result[decor_id] = slot_index
	return result


func _restore_decor_item_to_bag(
	decor_id: StringName,
	preferred_hotbar_slot: int,
) -> bool:
	if _bag == null:
		return false
	var prepared_slot: int = -1
	if (
		_inventory_layout != null
		and _hotbar != null
		and _inventory_layout.get_container(
			PlayerInventoryLayout.EntryKind.ITEM, decor_id
		) < 0
	):
		var candidate_slot: int = preferred_hotbar_slot
		if candidate_slot < 0:
			candidate_slot = _hotbar.find_first_empty_slot()
		if candidate_slot >= 0 and _inventory_layout.prepare_new_item_placement(
			decor_id,
			PlayerInventoryLayout.InventoryContainer.HOTBAR,
			candidate_slot,
		):
			prepared_slot = candidate_slot
	var restored: bool = _bag.add_item(decor_id, 1)
	if not restored:
		if prepared_slot >= 0:
			_inventory_layout.cancel_prepared_item_placement(decor_id)
		if _bag.get_owned_item(decor_id) == null:
			restored = _bag.add_item_to_storage(decor_id, 1)
	if restored and prepared_slot >= 0:
		_hotbar.assign_item(prepared_slot, decor_id)
		_hotbar.select_slot(prepared_slot)
	return restored


func _get_local_decor_rejection_transaction(
	canonical_revision: int,
) -> Dictionary:
	var revisions: Array[int] = []
	revisions.assign(_pending_local_decor_transactions.keys())
	revisions.sort()
	for revision: int in revisions:
		if canonical_revision < 0 or revision > canonical_revision:
			return _pending_local_decor_transactions[revision].duplicate(true)
	return {}


func _discard_local_decor_transactions_through(revision: int) -> void:
	for pending_revision: int in _pending_local_decor_transactions.keys():
		if pending_revision <= revision:
			_pending_local_decor_transactions.erase(pending_revision)


func _discard_local_decor_transactions_after(revision: int) -> void:
	for pending_revision: int in _pending_local_decor_transactions.keys():
		if pending_revision > revision:
			_pending_local_decor_transactions.erase(pending_revision)


func _trim_pending_local_decor_transactions() -> void:
	var revisions: Array[int] = []
	revisions.assign(_pending_local_decor_transactions.keys())
	revisions.sort()
	while revisions.size() > MAX_PENDING_LOCAL_DECOR_TRANSACTIONS:
		_pending_local_decor_transactions.erase(revisions.pop_front())


func _submit_transition(action: int, owner_fingerprint: String) -> bool:
	var request: Dictionary = {
		"request_id": _new_id("home_transition"),
		"session_id": _session.get_session_id(),
		"action": action,
		"owner_fingerprint": owner_fingerprint,
	}
	request["sender_signature"] = _session.sign_local_action(
		"portable_home_transition",
		NetworkHomeProtocolType.transition_signature_fields(request),
	)
	if _session.is_host():
		_process_transition_request(_session.get_local_peer_id(), request)
	else:
		submit_home_transition.rpc_id(1, request)
	return true


@rpc(
	"any_peer", "call_remote", "reliable",
	NetworkHomeProtocolType.RELIABLE_CHANNEL,
)
func submit_home_transition(data: Dictionary) -> void:
	var sender_id: int = multiplayer.get_remote_sender_id()
	if (
		not _session.is_host()
		or not _session.is_authenticated_peer(sender_id)
	):
		return
	_process_transition_request(sender_id, data)


func _process_transition_request(peer_id: int, data: Dictionary) -> void:
	if (
		not NetworkHomeProtocolType.validate_transition_request(data)
		or str(data["session_id"]) != _session.get_session_id()
		or not _session.verify_peer_action(
			peer_id,
			"portable_home_transition",
			NetworkHomeProtocolType.transition_signature_fields(data),
			data["sender_signature"],
		)
	):
		_send_transition_rejection(peer_id, "The RV transition was invalid.")
		return
	var owner_fingerprint: String = str(data["owner_fingerprint"])
	var action: int = int(data["action"])
	var avatar: Player = _spawn_service.get_avatar(peer_id)
	var manifest: Dictionary = _manifests_by_fingerprint.get(
		owner_fingerprint, {}
	)
	if avatar == null or manifest.is_empty():
		_send_transition_rejection(peer_id, "That RV is unavailable.")
		return
	if action == NetworkHomeProtocolType.TransitionAction.ENTER:
		var record := _session.get_peer_record(peer_id)
		var owner_is_local: bool = (
			record != null and record.identity_fingerprint == owner_fingerprint
		)
		var privacy: int = int((manifest["home"] as Dictionary)["privacy"])
		if (
			(not owner_is_local and privacy != PlayerHomeStateType.Privacy.OPEN)
			or _session.get_peer_space(peer_id)
				!= NetworkHomeProtocolType.WORLD_SPACE
			or not _world_service.is_avatar_near_exterior(
				avatar, owner_fingerprint
			)
		):
			_send_transition_rejection(peer_id, "You cannot enter that RV.")
			return
		var interior_space: StringName = (
			NetworkHomeProtocolType.make_space_id(owner_fingerprint)
		)
		var visitor_slot: int = _reserve_interior_slot(
			interior_space, peer_id
		)
		_apply_host_transition(
			peer_id,
			interior_space,
			owner_fingerprint,
			_world_service.get_interior_spawn_transform(
				owner_fingerprint, visitor_slot
			),
		)
		return
	if (
		_session.get_peer_space(peer_id)
			!= NetworkHomeProtocolType.make_space_id(owner_fingerprint)
		or not _world_service.is_avatar_near_interior_exit(
			avatar, owner_fingerprint
		)
	):
		_send_transition_rejection(peer_id, "Move closer to the RV door.")
		return
	_apply_host_transition(
		peer_id,
		NetworkHomeProtocolType.WORLD_SPACE,
		owner_fingerprint,
		_world_service.get_exterior_spawn_transform(owner_fingerprint),
	)


func _spawn_peer_at_exterior(
	peer_id: int,
	owner_fingerprint: String,
) -> void:
	if (
		not _session.is_host()
		or _session.get_peer_space(peer_id)
			!= NetworkHomeProtocolType.WORLD_SPACE
		or _spawn_service.get_avatar(peer_id) == null
	):
		return
	_apply_host_transition(
		peer_id,
		NetworkHomeProtocolType.WORLD_SPACE,
		owner_fingerprint,
		_world_service.get_exterior_spawn_transform(owner_fingerprint),
	)


func _apply_host_transition(
	peer_id: int,
	space_id: StringName,
	owner_fingerprint: String,
	transform: Transform3D,
) -> void:
	var avatar: Player = _spawn_service.get_avatar(peer_id)
	var movement_sequence: int = 0
	if avatar != null:
		movement_sequence = int(
			avatar.make_network_snapshot(peer_id).get(
				"acknowledged_input", 0
			)
		)
	var transform_data: Array[float] = (
		NetworkHomeProtocolType.transform_to_array(transform)
	)
	if not NetworkHomeProtocolType.validate_transition_transform(
		transform_data
	):
		push_error("Refused an out-of-bounds RV transition transform.")
		return
	var previous_space: StringName = _session.get_peer_space(peer_id)
	if (
		String(previous_space).begins_with("rv:")
		and previous_space != space_id
	):
		_release_interior_slot(previous_space, peer_id)
	var result: Dictionary = {
		"peer_id": peer_id,
		"space_id": String(space_id),
		"owner_fingerprint": owner_fingerprint,
		"transform": transform_data,
		"movement_sequence": movement_sequence,
	}
	_apply_transition_result(result)
	for recipient_id: int in _session.get_authenticated_peer_ids():
		if recipient_id == 1:
			continue
		receive_home_transition.rpc_id(recipient_id, result)


@rpc(
	"authority", "call_remote", "reliable",
	NetworkHomeProtocolType.RELIABLE_CHANNEL,
)
func receive_home_transition(data: Dictionary) -> void:
	if (
		typeof(data.get("peer_id")) != TYPE_INT
		or typeof(data.get("space_id")) not in [TYPE_STRING, TYPE_STRING_NAME]
		or typeof(data.get("movement_sequence", 0)) != TYPE_INT
		or int(data.get("movement_sequence", 0)) < 0
		or not NetworkIdentityCrypto.valid_fingerprint(
			data.get("owner_fingerprint")
		)
		or not NetworkHomeProtocolType.validate_transition_transform(
			data.get("transform")
		)
	):
		return
	_apply_transition_result(data)


func _apply_transition_result(data: Dictionary) -> void:
	var peer_id: int = int(data["peer_id"])
	var space_id := StringName(str(data["space_id"]))
	if not NetworkHomeProtocolType.validate_transition_transform(
		data.get("transform")
	):
		return
	var target_transform: Transform3D = (
		NetworkHomeProtocolType.array_to_transform(data["transform"])
	)
	if not _session.set_peer_space(peer_id, space_id):
		return
	if not _session.apply_authoritative_space_transition(
		peer_id,
		target_transform,
		int(data.get("movement_sequence", 0)),
	):
		return
	if peer_id == _session.get_local_peer_id():
		_world_service.set_local_space(space_id)
		local_space_changed.emit(space_id, str(data["owner_fingerprint"]))
		local_transition_finished.emit(true, "")
	_refresh_peer_visibility()


func _send_transition_rejection(peer_id: int, message: String) -> void:
	if peer_id == _session.get_local_peer_id():
		local_transition_finished.emit(false, message)
	else:
		receive_home_transition_rejection.rpc_id(peer_id, message)


@rpc(
	"authority", "call_remote", "reliable",
	NetworkHomeProtocolType.RELIABLE_CHANNEL,
)
func receive_home_transition_rejection(message: String) -> void:
	local_transition_finished.emit(
		false, message.left(NetworkHomeProtocolType.MAX_MESSAGE_LENGTH)
	)


func _refresh_peer_visibility() -> void:
	var local_peer_id: int = _session.get_local_peer_id()
	if local_peer_id <= 0:
		return
	for peer_id: int in _spawn_service.get_peer_ids():
		if peer_id == local_peer_id:
			continue
		_spawn_service.set_peer_presentation_visible(
			peer_id, _session.peers_share_space(local_peer_id, peer_id)
		)


func _on_local_home_changed() -> void:
	if _suppress_local_submission or _publish_queued:
		return
	_publish_queued = true
	call_deferred("_publish_queued_home")


func _publish_queued_home() -> void:
	if has_pending_local_decor_mutation():
		return
	_publish_queued = false
	if _save_manager != null:
		_save_manager.save_if_dirty()
	publish_local_home()


func _flush_queued_local_home_publish() -> void:
	if not _publish_queued or has_pending_local_decor_mutation():
		return
	call_deferred("_publish_queued_home")


func _on_join_authenticated() -> void:
	publish_local_home()


func _on_peer_authenticated(peer_id: int, _display_name: String) -> void:
	if not _session.is_host():
		return
	for manifest: Dictionary in _manifests_by_fingerprint.values():
		receive_home_manifest.rpc_id(peer_id, manifest)
	for existing_peer_id: int in _session.get_authenticated_peer_ids():
		if existing_peer_id == peer_id:
			continue
		var avatar: Player = _spawn_service.get_avatar(existing_peer_id)
		if avatar == null:
			continue
		var space_id: StringName = _session.get_peer_space(existing_peer_id)
		var owner_fingerprint: String = (
			String(space_id).trim_prefix("rv:")
			if String(space_id).begins_with("rv:")
			else _fingerprint_for_peer(existing_peer_id)
		)
		if owner_fingerprint.is_empty():
			continue
		receive_home_transition.rpc_id(peer_id, {
			"peer_id": existing_peer_id,
			"space_id": String(space_id),
			"owner_fingerprint": owner_fingerprint,
			"transform": NetworkHomeProtocolType.transform_to_array(
				avatar.global_transform
			),
		})


func _on_peer_removed(peer_id: int) -> void:
	_release_peer_interior_slots(peer_id)
	var fingerprint: String = _fingerprint_by_peer.get(peer_id, "")
	_fingerprint_by_peer.erase(peer_id)
	_authorized_owned_counts.erase(peer_id)
	if fingerprint.is_empty():
		return
	if _session.is_host():
		for occupant_id: int in _session.get_authenticated_peer_ids():
			if (
				occupant_id == peer_id
				or _session.get_peer_space(occupant_id)
					!= NetworkHomeProtocolType.make_space_id(fingerprint)
			):
				continue
			_apply_host_transition(
				occupant_id,
				NetworkHomeProtocolType.WORLD_SPACE,
				fingerprint,
				_world_service.get_exterior_spawn_transform(fingerprint),
			)
	_manifests_by_fingerprint.erase(fingerprint)
	_world_service.remove_presentation(fingerprint)
	if _session.is_host():
		for recipient_id: int in _session.get_authenticated_peer_ids():
			if recipient_id != 1:
				receive_home_removed.rpc_id(recipient_id, fingerprint)


@rpc(
	"authority", "call_remote", "reliable",
	NetworkHomeProtocolType.RELIABLE_CHANNEL,
)
func receive_home_removed(owner_fingerprint: String) -> void:
	if not NetworkIdentityCrypto.valid_fingerprint(owner_fingerprint):
		return
	_manifests_by_fingerprint.erase(owner_fingerprint)
	_world_service.remove_presentation(owner_fingerprint)


func _on_session_state_changed(state: NetworkSession.State) -> void:
	if state in [NetworkSession.State.PRIVATE_HOST, NetworkSession.State.OPEN_HOST]:
		if (
			not _session.is_dedicated_host()
			and _world_service != null
			and _world_service.is_world_ready()
		):
			publish_local_home()
		return
	if state in [
		NetworkSession.State.INACTIVE,
		NetworkSession.State.DISCONNECTING,
		NetworkSession.State.CONNECTION_FAILED,
		NetworkSession.State.SERVER_LOST,
	]:
		_manifests_by_fingerprint.clear()
		_fingerprint_by_peer.clear()
		_authorized_owned_counts.clear()
		_authorization_result_owner.clear()
		_publish_queued = false
		_last_submitted_local_home_revision = -1
		_pending_local_decor_transactions.clear()
		_interior_slots_by_space.clear()
		_next_interior_index = 0
		_world_service.clear_presentations()
		_world_service.set_local_space(NetworkHomeProtocolType.WORLD_SPACE)
		local_space_changed.emit(NetworkHomeProtocolType.WORLD_SPACE, "")


func _fingerprint_for_peer(peer_id: int) -> String:
	if _fingerprint_by_peer.has(peer_id):
		return _fingerprint_by_peer[peer_id]
	var record := _session.get_peer_record(peer_id)
	return record.identity_fingerprint if record != null else ""


func _reserve_interior_slot(space_id: StringName, peer_id: int) -> int:
	var slots: Dictionary = _interior_slots_by_space.get(space_id, {})
	if slots.has(peer_id):
		return int(slots[peer_id])
	var used_slots: Dictionary[int, bool] = {}
	for value: Variant in slots.values():
		used_slots[int(value)] = true
	var slot: int = 0
	while used_slots.has(slot):
		slot += 1
	slots[peer_id] = slot
	_interior_slots_by_space[space_id] = slots
	return slot


func _release_interior_slot(space_id: StringName, peer_id: int) -> void:
	var slots: Dictionary = _interior_slots_by_space.get(space_id, {})
	if slots.is_empty():
		return
	slots.erase(peer_id)
	if slots.is_empty():
		_interior_slots_by_space.erase(space_id)
	else:
		_interior_slots_by_space[space_id] = slots


func _release_peer_interior_slots(peer_id: int) -> void:
	for space_id: StringName in _interior_slots_by_space.keys():
		_release_interior_slot(space_id, peer_id)


func _new_id(prefix: String) -> String:
	return "%s:%s" % [
		prefix, Crypto.new().generate_random_bytes(16).hex_encode(),
	]