class_name SituationDefinition
extends Resource

@export var situation_definition_id: StringName
@export var display_name: String
@export_multiline var description: String
@export_range(0, 100, 1) var severity := 1
@export_range(-100, 100, 1) var priority := 0
@export var trigger_predicates: Array[SituationPredicate] = []
@export var resolution_predicates: Array[SituationPredicate] = []
@export var expiry_predicate_ids: Array[StringName] = []
@export var dedupe_key_fields: Array[StringName] = []
@export_range(0, 1000000, 1) var expiry_ticks := 0
@export_range(0, 1000000, 1) var cooldown_ticks := 0
@export var dialogue_topic_ids: Array[StringName] = []
@export var dialogue_intent_ids: Array[StringName] = []
@export var alternatives: Array[SituationAlternativeDefinition] = []


func validate(
	supported_event_predicate_ids: Array[StringName] = [],
	supported_state_predicate_ids: Array[StringName] = [],
	supported_expiry_predicate_ids: Array[StringName] = []
) -> Array[String]:
	var errors: Array[String] = []
	if situation_definition_id.is_empty():
		errors.append("situation_definition_id is empty")
	if display_name.is_empty():
		errors.append("display_name is empty for '%s'" % situation_definition_id)
	if trigger_predicates.is_empty():
		errors.append("'%s' has no trigger predicates" % situation_definition_id)
	if severity < 0 or severity > 100:
		errors.append("severity is outside 0..100 for '%s'" % situation_definition_id)
	if priority < -100 or priority > 100:
		errors.append("priority is outside -100..100 for '%s'" % situation_definition_id)
	if expiry_ticks < 0 or cooldown_ticks < 0:
		errors.append("expiry/cooldown ticks cannot be negative for '%s'" % situation_definition_id)
	_validate_predicates(
		trigger_predicates,
		"trigger",
		supported_event_predicate_ids,
		supported_state_predicate_ids,
		errors
	)
	_validate_predicates(
		resolution_predicates,
		"resolution",
		supported_event_predicate_ids,
		supported_state_predicate_ids,
		errors
	)
	for predicate_id in expiry_predicate_ids:
		if predicate_id.is_empty():
			errors.append("'%s' has an empty expiry predicate ID" % situation_definition_id)
		elif (
			not supported_expiry_predicate_ids.is_empty()
			and predicate_id not in supported_expiry_predicate_ids
		):
			errors.append(
				(
					"'%s' references unsupported expiry predicate '%s'"
					% [situation_definition_id, predicate_id]
				)
			)
	_validate_unique_names(dedupe_key_fields, "dedupe key", errors)
	_validate_unique_names(dialogue_topic_ids, "dialogue topic", errors)
	_validate_unique_names(dialogue_intent_ids, "dialogue intent", errors)
	var predicate_ids := {}
	for predicate in trigger_predicates + resolution_predicates:
		if predicate == null:
			continue
		if predicate_ids.has(predicate.predicate_id):
			errors.append(
				(
					"'%s' has duplicate predicate '%s' across trigger/resolution predicates"
					% [situation_definition_id, predicate.predicate_id]
				)
			)
		predicate_ids[predicate.predicate_id] = true
	var alternatives_by_id: Dictionary = {}
	for alternative in alternatives:
		if alternative == null:
			errors.append("'%s' contains a null alternative" % situation_definition_id)
			continue
		for error in alternative.validate():
			errors.append("Alternative '%s': %s" % [alternative.alternative_id, error])
		if alternatives_by_id.has(alternative.alternative_id):
			errors.append(
				(
					"'%s' has duplicate alternative '%s'"
					% [situation_definition_id, alternative.alternative_id]
				)
			)
		alternatives_by_id[alternative.alternative_id] = true
		for predicate_id in alternative.resolution_predicate_ids:
			if not _has_predicate(predicate_id):
				errors.append(
					(
						"Alternative '%s' references unknown resolution predicate '%s'"
						% [alternative.alternative_id, predicate_id]
					)
				)
	return errors


func duplicate_definition() -> SituationDefinition:
	var copy := SituationDefinition.new()
	copy.situation_definition_id = situation_definition_id
	copy.display_name = display_name
	copy.description = description
	copy.severity = severity
	copy.priority = priority
	for predicate in trigger_predicates:
		copy.trigger_predicates.append(
			predicate.duplicate_predicate() if predicate != null else null
		)
	for predicate in resolution_predicates:
		copy.resolution_predicates.append(
			predicate.duplicate_predicate() if predicate != null else null
		)
	copy.expiry_predicate_ids = expiry_predicate_ids.duplicate()
	copy.dedupe_key_fields = dedupe_key_fields.duplicate()
	copy.expiry_ticks = expiry_ticks
	copy.cooldown_ticks = cooldown_ticks
	copy.dialogue_topic_ids = dialogue_topic_ids.duplicate()
	copy.dialogue_intent_ids = dialogue_intent_ids.duplicate()
	for alternative in alternatives:
		copy.alternatives.append(
			alternative.duplicate_alternative() if alternative != null else null
		)
	return copy


func get_predicate(predicate_id: StringName) -> SituationPredicate:
	for predicate in trigger_predicates:
		if predicate != null and predicate.predicate_id == predicate_id:
			return predicate
	for predicate in resolution_predicates:
		if predicate != null and predicate.predicate_id == predicate_id:
			return predicate
	return null


func get_alternative(alternative_id: StringName) -> SituationAlternativeDefinition:
	for alternative in alternatives:
		if alternative != null and alternative.alternative_id == alternative_id:
			return alternative
	return null


func _has_predicate(predicate_id: StringName) -> bool:
	return get_predicate(predicate_id) != null


func _validate_predicates(
	predicates: Array[SituationPredicate],
	label: String,
	supported_event_ids: Array[StringName],
	supported_state_ids: Array[StringName],
	errors: Array[String]
) -> void:
	var seen: Dictionary = {}
	for predicate in predicates:
		if predicate == null:
			errors.append("'%s' contains a null %s predicate" % [situation_definition_id, label])
			continue
		for error in predicate.validate():
			errors.append(
				"%s predicate '%s': %s" % [label.capitalize(), predicate.predicate_id, error]
			)
		if seen.has(predicate.predicate_id):
			errors.append(
				(
					"'%s' has duplicate %s predicate '%s'"
					% [situation_definition_id, label, predicate.predicate_id]
				)
			)
		seen[predicate.predicate_id] = true
		var supported_ids := (
			supported_event_ids
			if StringName(predicate.source) == SituationPredicate.SOURCE_EVENT
			else supported_state_ids
		)
		if not supported_ids.is_empty() and predicate.evaluator_id not in supported_ids:
			errors.append(
				(
					"'%s' references unsupported %s predicate '%s'"
					% [situation_definition_id, predicate.source, predicate.evaluator_id]
				)
			)


func _validate_unique_names(names: Array[StringName], label: String, errors: Array[String]) -> void:
	var seen: Dictionary = {}
	for name in names:
		if name.is_empty():
			errors.append("'%s' has an empty %s" % [situation_definition_id, label])
		elif seen.has(name):
			errors.append("'%s' has duplicate %s '%s'" % [situation_definition_id, label, name])
		seen[name] = true