class_name ActivityEventValidator
extends RefCounted

static var _core_catalog: ContentCatalog
static var _core_storage_routing: StorageRoutingPolicy


static func is_candidate(event: EconomicEventRecord) -> bool:
	if event == null:
		return false
	if StringName(event.data.get("event_type", &"")) == SimulationIds.EVENT_TASK_BLOCKED:
		return false
	if StringName(event.data.get("target_kind", &"")) == SimulationIds.TARGET_ACTIVITY:
		return true
	var event_type := StringName(event.data.get("event_type", &""))
	return SimulationDefinitions.has_action_event_type(event_type)


static func is_valid(
	event: EconomicEventRecord,
	expected_world_id: StringName = &"",
	expected_location_id: StringName = &""
) -> bool:
	if event == null or not _has_activity_fields(event):
		return false
	var actor_id := int(event.data["actor_id"])
	var action_id := StringName(event.data["action_id"])
	var definition := SimulationDefinitions.get_action(action_id)
	var effect := ActivityActionCommandService._metric_effect(definition)
	if (
		not KnownEventStateRecord.is_valid_actor_id(actor_id)
		or definition == null
		or effect == null
		or definition.target_type != SimulationIds.TARGET_ACTIVITY
		or definition.completion_handler_id != ActivityActionCommandService.HANDLER_METRIC_DELTA
		or StringName(event.data["event_type"]) != definition.event_type_id
		or StringName(event.data["source_id"]).is_empty()
		or not StringName(event.data["destination_id"]).is_empty()
		or StringName(event.data["target_kind"]) != SimulationIds.TARGET_ACTIVITY
		or StringName(event.data["target_action_id"]) != action_id
		or StringName(event.data["world_id"]).is_empty()
		or StringName(event.data["location_id"]).is_empty()
		or (
			not expected_world_id.is_empty()
			and StringName(event.data["world_id"]) != expected_world_id
		)
		or (
			not expected_location_id.is_empty()
			and StringName(event.data["location_id"]) != expected_location_id
		)
	):
		return false
	var metric_delta_value: Variant = event.data["metric_delta"]
	var cost_amount_value: Variant = event.data["cost_amount"]
	if (
		(metric_delta_value is not int and metric_delta_value is not float)
		or (cost_amount_value is not int and cost_amount_value is not float)
	):
		return false
	var metric_delta := float(metric_delta_value)
	var cost_amount := float(cost_amount_value)
	var maximum_delta := _maximum_delta(effect, actor_id)
	return (
		is_finite(metric_delta)
		and metric_delta > 0.0
		and is_finite(maximum_delta)
		and maximum_delta > 0.0
		and (metric_delta < maximum_delta or is_equal_approx(metric_delta, maximum_delta))
		and is_finite(cost_amount)
		and StringName(event.data["metric_id"]) == effect.subject_key
		and StringName(event.data["cost_item_id"]) == definition.completion_cost_resource_id
		and StringName(event.data["item_id"]) == definition.completion_cost_resource_id
		and is_equal_approx(cost_amount, definition.completion_cost_amount)
		and is_equal_approx(float(event.data["required_amount"]), definition.completion_cost_amount)
	)


static func is_valid_for_state(
	event: EconomicEventRecord,
	npc_ids: Dictionary,
	current_tick: int,
	expected_world_id: StringName = &"",
	expected_location_id: StringName = &""
) -> bool:
	if (
		not is_valid(event, expected_world_id, expected_location_id)
		or int(event.data["tick"]) > current_tick
	):
		return false
	var actor_id := int(event.data["actor_id"])
	return actor_id == SimulationIds.PLAYER_ACTOR_ID or npc_ids.has(actor_id)


static func is_blocked_candidate(event: EconomicEventRecord) -> bool:
	return (
		event != null
		and StringName(event.data.get("event_type", &"")) == SimulationIds.EVENT_TASK_BLOCKED
	)


static func is_valid_blocked(
	event: EconomicEventRecord,
	expected_world_id: StringName = &"",
	expected_location_id: StringName = &""
) -> bool:
	if event == null or not _has_blocked_fields(event):
		return false
	if is_legacy_unstructured_blocked(event):
		return _is_valid_legacy_unstructured_blocked(event, expected_world_id, expected_location_id)
	var actor_id := int(event.data["actor_id"])
	var action_id := StringName(event.data["action_id"])
	var definition := SimulationDefinitions.get_action(action_id)
	if (
		StringName(event.data["event_type"]) != SimulationIds.EVENT_TASK_BLOCKED
		or not KnownEventStateRecord.is_valid_actor_id(actor_id)
		or definition == null
		or not definition.has_completion_cost()
		or (
			StringName(event.data["blocked_contract_kind"])
			!= SimulationIds.BLOCKED_CONTRACT_ACTION_COST
		)
		or StringName(event.data["item_id"]) != definition.completion_cost_resource_id
		or not is_equal_approx(
			float(event.data["required_amount"]), definition.completion_cost_amount
		)
		or StringName(event.data["source_id"]).is_empty()
		or not StringName(event.data["destination_id"]).is_empty()
		or not is_zero_approx(float(event.data["amount"]))
		or StringName(event.data["world_id"]).is_empty()
		or StringName(event.data["location_id"]).is_empty()
		or (
			not expected_world_id.is_empty()
			and StringName(event.data["world_id"]) != expected_world_id
		)
		or (
			not expected_location_id.is_empty()
			and StringName(event.data["location_id"]) != expected_location_id
		)
	):
		return false
	var route := _get_core_storage_routing().resolve_definition(
		definition.completion_cost_resource_id
	)
	if route == null or not _blocked_source_matches(event, action_id, actor_id, route.storage_id):
		return false
	if event.data.has("activity_target_id"):
		return (
			definition.target_type == SimulationIds.TARGET_ACTIVITY
			and (
				definition.completion_handler_id
				== SimulationIds.ACTION_HANDLER_ACTIVITY_METRIC_DELTA
			)
			and not StringName(event.data["activity_target_id"]).is_empty()
			and StringName(event.data.get("target_kind", &"")) == SimulationIds.TARGET_ACTIVITY
			and StringName(event.data.get("target_action_id", &"")) == action_id
		)
	return true


static func _blocked_source_matches(
	event: EconomicEventRecord, action_id: StringName, actor_id: int, routed_storage_id: StringName
) -> bool:
	var source_id := StringName(event.data["source_id"])
	if source_id == routed_storage_id:
		return true
	return (
		action_id == SimulationIds.ACTION_FEED_ANIMAL
		and actor_id >= 0
		and source_id == SimulationIds.npc_inventory_id(actor_id)
	)


static func is_valid_blocked_for_state(
	event: EconomicEventRecord,
	npc_ids: Dictionary,
	storage_records_by_id: Dictionary,
	current_tick: int,
	expected_world_id: StringName = &"",
	expected_location_id: StringName = &""
) -> bool:
	if (
		not is_valid_blocked(event, expected_world_id, expected_location_id)
		or int(event.data["tick"]) > current_tick
	):
		return false
	var actor_id := int(event.data["actor_id"])
	if actor_id != SimulationIds.PLAYER_ACTOR_ID and not npc_ids.has(actor_id):
		return false
	if is_legacy_unstructured_blocked(event):
		return true
	var source_id := StringName(event.data["source_id"])
	return (
		storage_records_by_id.has(source_id)
		or (
			StringName(event.data["action_id"]) == SimulationIds.ACTION_FEED_ANIMAL
			and actor_id >= 0
			and source_id == SimulationIds.npc_inventory_id(actor_id)
		)
	)


static func is_legacy_unstructured_blocked(event: EconomicEventRecord) -> bool:
	return (
		event != null
		and StringName(event.data.get("event_type", &"")) == SimulationIds.EVENT_TASK_BLOCKED
		and (
			StringName(event.data.get("blocked_contract_kind", &""))
			== SimulationIds.BLOCKED_CONTRACT_LEGACY_UNSTRUCTURED
		)
	)


static func _is_valid_legacy_unstructured_blocked(
	event: EconomicEventRecord, expected_world_id: StringName, expected_location_id: StringName
) -> bool:
	var legacy_version := int(event.data.get("legacy_world_schema_version", -1))
	return (
		(
			legacy_version
			in range(
				EconomicEventRecord.LEGACY_BLOCKED_WORLD_SCHEMA_MIN,
				EconomicEventRecord.LEGACY_BLOCKED_WORLD_SCHEMA_MAX + 1
			)
		)
		and KnownEventStateRecord.is_valid_actor_id(int(event.data["actor_id"]))
		and StringName(event.data["action_id"]).is_empty()
		and StringName(event.data["item_id"]).is_empty()
		and is_zero_approx(float(event.data["required_amount"]))
		and StringName(event.data["destination_id"]).is_empty()
		and is_zero_approx(float(event.data["amount"]))
		and not StringName(event.data["world_id"]).is_empty()
		and not StringName(event.data["location_id"]).is_empty()
		and (
			expected_world_id.is_empty() or StringName(event.data["world_id"]) == expected_world_id
		)
		and (
			expected_location_id.is_empty()
			or StringName(event.data["location_id"]) == expected_location_id
		)
	)


static func _has_activity_fields(event: EconomicEventRecord) -> bool:
	return (
		event
		. data
		. has_all(
			[
				"metric_id",
				"metric_delta",
				"cost_item_id",
				"cost_amount",
				"target_kind",
				"target_action_id",
				"world_id",
				"location_id",
			]
		)
	)


static func _has_blocked_fields(event: EconomicEventRecord) -> bool:
	return (
		event
		. data
		. has_all(
			[
				"blocked_contract_kind",
				"world_id",
				"location_id",
				"action_id",
				"item_id",
				"required_amount",
			]
		)
	)


static func _maximum_delta(effect: ActionEffect, actor_id: int) -> float:
	var maximum_delta := effect.value
	if actor_id != SimulationIds.PLAYER_ACTOR_ID:
		return maximum_delta
	var raw_multiplier: Variant = effect.parameters.get("player_multiplier", 1.0)
	if raw_multiplier is not int and raw_multiplier is not float:
		return -1.0
	return maximum_delta * float(raw_multiplier)


static func _get_core_storage_routing() -> StorageRoutingPolicy:
	if _core_storage_routing == null:
		_core_catalog = ContentCatalog.create_core()
		_core_storage_routing = StorageRoutingPolicy.new(_core_catalog)
	return _core_storage_routing