class_name UpdateManager
extends Node

signal update_available(info: Dictionary)

const RELEASES_API := "https://git.dominicspringer.de/api/v1/repos/Emporex/Void-Bastion-Releases/releases"
const PUBLIC_RELEASE_BASE := "https://git.dominicspringer.de/Emporex/Void-Bastion-Releases/releases/tag/"

var _request: HTTPRequest


func _ready() -> void:
	if DisplayServer.get_name() == "headless" or Engine.is_editor_hint():
		return
	_request = HTTPRequest.new()
	add_child(_request)
	_request.request_completed.connect(_on_request_completed)
	call_deferred("check_for_update")


func check_for_update() -> void:
	if _request == null or _request.get_http_client_status() != HTTPClient.STATUS_DISCONNECTED:
		return
	_request.request(RELEASES_API, ["Accept: application/json", "User-Agent: Void-Bastion/%s" % _current_version()])


func _on_request_completed(result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	if result != HTTPRequest.RESULT_SUCCESS or response_code < 200 or response_code >= 300:
		return
	var releases = JSON.parse_string(body.get_string_from_utf8())
	if not releases is Array:
		return
	for release in releases:
		if not release is Dictionary or bool(release.get("draft", false)):
			continue
		var version := str(release.get("tag_name", "")).trim_prefix("v")
		if version.is_empty() or not _is_newer_version(version, _current_version()):
			return
		var download_url := PUBLIC_RELEASE_BASE + "v" + version
		var wanted_extension := ".apk" if OS.get_name() == "Android" else ".exe"
		for asset in release.get("assets", []):
			if asset is Dictionary and str(asset.get("name", "")).to_lower().ends_with(wanted_extension):
				download_url = str(asset.get("browser_download_url", download_url))
				break
		update_available.emit({
			"version": version,
			"name": str(release.get("name", version)),
			"url": download_url
		})
		return


func _current_version() -> String:
	return str(ProjectSettings.get_setting("application/config/version", "0.0.0"))


func _is_newer_version(remote: String, local: String) -> bool:
	var remote_parts := _version_parts(remote)
	var local_parts := _version_parts(local)
	for index in 3:
		if remote_parts[index] != local_parts[index]:
			return remote_parts[index] > local_parts[index]
	var remote_suffix: String = remote_parts[3]
	var local_suffix: String = local_parts[3]
	if remote_suffix.is_empty():
		return not local_suffix.is_empty()
	if local_suffix.is_empty():
		return false
	return _prerelease_weight(remote_suffix) > _prerelease_weight(local_suffix)


func _version_parts(value: String) -> Array:
	var normalized := value.trim_prefix("v").strip_edges().to_lower()
	var sections := normalized.split("-", true, 1)
	var numbers := sections[0].split(".")
	return [
		int(numbers[0]) if numbers.size() > 0 else 0,
		int(numbers[1]) if numbers.size() > 1 else 0,
		int(numbers[2]) if numbers.size() > 2 else 0,
		sections[1] if sections.size() > 1 else ""
	]


func _prerelease_weight(value: String) -> int:
	var stage := 0
	if value.begins_with("beta"):
		stage = 100000
	elif value.begins_with("rc"):
		stage = 200000
	var sequence := 0
	for part in value.split("."):
		if part.is_valid_int():
			sequence = int(part)
	return stage + sequence