class_name AgonesSDK
extends Node

# Dependency-free REST bridge for the Agones sidecar. The Go supervisor owns
# the process-ready probe and /ready transition; this node owns the game
# process's periodic Health pings and terminal Shutdown/annotation calls.

const HEALTH_INTERVAL_SECONDS := 2.0
const REQUEST_TIMEOUT_SECONDS := 2.0
const MAX_ANNOTATION_VALUE_LENGTH := 4096

var _base_url := ""
var _health_timer: Timer = null
var _health_in_flight := false


func configure_from_environment() -> bool:
	var port := OS.get_environment("AGONES_SDK_HTTP_PORT")
	if port.is_empty() or not port.is_valid_int() or int(port) < 1 or int(port) > 65535:
		return false
	_base_url = "http://127.0.0.1:%d" % int(port)
	return true


func configure_for_testing(base_url: String) -> bool:
	if not base_url.begins_with("http://127.0.0.1:") and not base_url.begins_with("http://localhost:"):
		return false
	_base_url = base_url.trim_suffix("/")
	return true


func is_available() -> bool:
	return not _base_url.is_empty()


func start_health() -> void:
	if not is_available() or _health_timer != null:
		return
	_health_timer = Timer.new()
	_health_timer.name = "AgonesHealth"
	_health_timer.wait_time = HEALTH_INTERVAL_SECONDS
	_health_timer.one_shot = false
	_health_timer.timeout.connect(_send_health)
	add_child(_health_timer)
	_health_timer.start()
	_send_health()


func stop_health() -> void:
	if _health_timer != null:
		_health_timer.stop()
		_health_timer.queue_free()
		_health_timer = null


func health() -> int:
	return await _request(HTTPClient.METHOD_POST, "/health", {})


func mark_ready() -> int:
	return await _request(HTTPClient.METHOD_POST, "/ready", {})


func shutdown() -> int:
	return await _request(HTTPClient.METHOD_POST, "/shutdown", {})


func set_annotation(key: String, value: String) -> int:
	if not annotation_is_valid(key, value):
		return 400
	return await _request(HTTPClient.METHOD_PUT, "/metadata/annotation", {"key": key, "value": value})


static func annotation_is_valid(key: String, value: String) -> bool:
	return not (key.is_empty() or value.is_empty() or value.length() > MAX_ANNOTATION_VALUE_LENGTH or "\n" in key or "\r" in key or "\n" in value or "\r" in value)


func _send_health() -> void:
	if _health_in_flight or not is_available():
		return
	_health_in_flight = true
	var status := await health()
	_health_in_flight = false
	if status < 200 or status >= 300:
		push_warning("Agones health ping failed (%d)" % status)


func _request(method: int, path: String, payload: Dictionary) -> int:
	if not is_available() or not path.begins_with("/"):
		return 408
	var request := HTTPRequest.new()
	request.timeout = REQUEST_TIMEOUT_SECONDS
	add_child(request)
	var body := JSON.stringify(payload)
	var err := request.request(_base_url + path, PackedStringArray(["Content-Type: application/json"]), method, body)
	if err != OK:
		request.queue_free()
		return 599
	var result = await request.request_completed
	request.queue_free()
	return int(result[1])