class_name AccessVerifier
extends RefCounted

const Rules := preload("res://src/core/rules.gd")
const AccessPolicy := preload("res://src/core/access_policy.gd")
const AccessArtifact := preload("res://src/core/access_artifact.gd")
## Evaluates access artifacts against a venue AccessPolicy.
## Pure logic: no UI, no Node dependency, fully headless-testable.

## Result dictionary contract:
## { granted: bool, reasons: Array[String], issues: Array[String],
##   decisive_artifacts: Array[String], checked_artifacts: Array[String] }

func _init() -> void:
	pass

## Verify a single person's set of artifacts (person_artifacts: Array[AccessArtifact]).
func verify(person_artifacts: Array, policy: AccessPolicy, already_screened: bool = false) -> Dictionary:
	var reasons: Array[String] = []
	var issues: Array[String] = []
	var checked: Array[String] = []

	for artifact in person_artifacts:
		if not (artifact is AccessArtifact):
			continue
		checked.append(artifact.summary())
		if artifact.kind == Rules.AccessKind.RECOGNITION and artifact.status == Rules.ArtifactStatus.VALID:
			reasons.append("Recognized by guard")
		elif artifact.status == Rules.ArtifactStatus.VALID:
			reasons.append("Valid %s" % Rules.ACCESS_KIND_NAMES.get(artifact.kind, "artifact"))
		elif artifact.status == Rules.ArtifactStatus.EXPIRED:
			issues.append("Expired %s" % Rules.ACCESS_KIND_NAMES.get(artifact.kind, "artifact"))
		elif artifact.status == Rules.ArtifactStatus.COUNTERFEIT:
			issues.append("Suspected counterfeit %s" % Rules.ACCESS_KIND_NAMES.get(artifact.kind, "artifact"))
		elif artifact.status == Rules.ArtifactStatus.MISMATCHED:
			issues.append("%s does not match person" % Rules.ACCESS_KIND_NAMES.get(artifact.kind, "artifact"))
		elif artifact.status == Rules.ArtifactStatus.AMBIGUOUS:
			issues.append("Ambiguous %s" % Rules.ACCESS_KIND_NAMES.get(artifact.kind, "artifact"))
		elif artifact.status == Rules.ArtifactStatus.MISSING:
			issues.append("Missing %s" % Rules.ACCESS_KIND_NAMES.get(artifact.kind, "artifact"))

	# Age check.
	if policy.minimum_age > 0 and require_age_info(person_artifacts, policy):
		var age := person_age(person_artifacts)
		if age < policy.minimum_age:
			issues.append("Underage (%d < %d)" % [age, policy.minimum_age])
			return _result(false, reasons, issues, checked)

	# Wand screening is processed by the interaction layer (false alarms), but a
	# policy can hard-require it; a refused screen blocks entry.
	if policy.wand_screening_required and not already_screened and not person_screened(person_artifacts):
		issues.append("Screening required")
		return _result(false, reasons, issues, checked)

	# Recognition short-circuits if present and valid.
	var recognized := false
	for artifact in person_artifacts:
		if artifact is AccessArtifact:
			if artifact.kind == Rules.AccessKind.RECOGNITION and artifact.status == Rules.ArtifactStatus.VALID:
				recognized = true
	if recognized:
		return _result(true, reasons, issues, checked)

	# Every required artifact kind must have a valid match (AND admission),
	# unless the policy grants on any single valid artifact (OR admission).
	var any_satisfied := false
	for kind in policy.required_artifacts.keys():
		var satisfied := false
		for artifact in person_artifacts:
			if artifact is AccessArtifact and artifact.kind == kind:
				if artifact.status == Rules.ArtifactStatus.VALID:
					satisfied = true
		any_satisfied = any_satisfied or satisfied
		if not satisfied:
			issues.append("Missing valid %s" % Rules.ACCESS_KIND_NAMES.get(kind, "credential"))
			if not policy.grant_if_any_required:
				return _result(false, reasons, issues, checked)
	if policy.grant_if_any_required and not any_satisfied:
		return _result(false, reasons, issues, checked)

	if policy.require_id:
		var id_ok := false
		for artifact in person_artifacts:
			if artifact is AccessArtifact and artifact.kind == Rules.AccessKind.ID and artifact.status == Rules.ArtifactStatus.VALID:
				id_ok = true
		if not id_ok:
			issues.append("Valid ID required")
			return _result(false, reasons, issues, checked)

	return _result(true, reasons, issues, checked)

func _result(granted: bool, reasons: Array, issues: Array, checked: Array) -> Dictionary:
	return {
		"granted": granted,
		"reasons": reasons,
		"issues": issues,
		"decisive_artifacts": reasons.duplicate(),
		"checked_artifacts": checked,
	}

func require_age_info(person_artifacts: Array, policy: AccessPolicy) -> bool:
	if policy.minimum_age <= 0:
		return false
	var id_present := false
	for artifact in person_artifacts:
		if artifact is AccessArtifact and artifact.kind == Rules.AccessKind.ID:
			id_present = true
	return id_present

func person_age(person_artifacts: Array) -> int:
	for artifact in person_artifacts:
		if artifact is AccessArtifact and artifact.kind == Rules.AccessKind.ID:
			var age: Variant = artifact.attributes.get("age", -1)
			if age is int and age > 0:
				return age
	return -1

func person_screened(person_artifacts: Array) -> bool:
	for artifact in person_artifacts:
		if artifact is AccessArtifact:
			if artifact.kind == Rules.AccessKind.CREDENTIAL and artifact.attributes.get("screened", false) == true:
				return true
	return false