class_name RelationshipStateRecord
extends RefCounted

const SCHEMA_VERSION := 1
const NO_CAUSE_EVENT := -1
const NEUTRAL_TRUST := 0.5

var data: Dictionary


func _init(record_data: Dictionary = {}) -> void:
	data = record_data.duplicate(true)


static func create(
	observer_id: int,
	subject_id: int,
	familiarity: float,
	trust: float = NEUTRAL_TRUST,
	last_trust_cause_event_id: int = NO_CAUSE_EVENT
) -> RelationshipStateRecord:
	return (
		RelationshipStateRecord
		. new(
			{
				"schema_version": SCHEMA_VERSION,
				"observer_id": observer_id,
				"subject_id": subject_id,
				"familiarity": clampf(familiarity, 0.0, 1.0),
				"trust": clampf(trust, 0.0, 1.0),
				"last_trust_cause_event_id": last_trust_cause_event_id,
			}
		)
	)


static func from_dictionary(record_data: Dictionary) -> RelationshipStateRecord:
	if int(record_data.get("schema_version", -1)) != SCHEMA_VERSION:
		return null
	if not record_data.has_all(
		["observer_id", "subject_id", "familiarity", "trust", "last_trust_cause_event_id"]
	):
		return null
	var observer_id := int(record_data["observer_id"])
	var subject_id := int(record_data["subject_id"])
	var familiarity := float(record_data["familiarity"])
	var trust := float(record_data["trust"])
	var cause_event_id := int(record_data["last_trust_cause_event_id"])
	if observer_id < 0 or subject_id < 0 or observer_id == subject_id:
		return null
	if familiarity < 0.0 or familiarity > 1.0 or trust < 0.0 or trust > 1.0:
		return null
	if cause_event_id < NO_CAUSE_EVENT:
		return null
	return create(observer_id, subject_id, familiarity, trust, cause_event_id)


func get_observer_id() -> int:
	return int(data["observer_id"])


func get_subject_id() -> int:
	return int(data["subject_id"])


func get_familiarity() -> float:
	return float(data["familiarity"])


func get_trust() -> float:
	return float(data["trust"])


func get_last_trust_cause_event_id() -> int:
	return int(data["last_trust_cause_event_id"])


func increase_familiarity(amount: float) -> float:
	var previous := get_familiarity()
	data["familiarity"] = clampf(previous + maxf(amount, 0.0), 0.0, 1.0)
	return get_familiarity() - previous


func increase_trust(amount: float, cause_event_id: int) -> float:
	var previous := get_trust()
	data["trust"] = clampf(previous + maxf(amount, 0.0), 0.0, 1.0)
	var applied := get_trust() - previous
	if applied > 0.0:
		data["last_trust_cause_event_id"] = cause_event_id
	return applied


func to_dictionary() -> Dictionary:
	return data.duplicate(true)