extends WorldPreview

# Uncached geometry and reflective service lookup oracle.
func get_map_rect() -> Rect2:
	var bounds := _world_bounds()
	if bounds.is_empty():
		return Rect2()
	var dimensions := _cell_dimensions()
	var map_size := Vector2(
		int(bounds[&"max_x"]) - int(bounds[&"min_x"]) + 1,
		int(bounds[&"max_y"]) - int(bounds[&"min_y"]) + 1
	) * dimensions
	return Rect2(((size - map_size) * 0.5 + pan_offset).floor(), map_size)


func _cell_dimensions() -> Vector2:
	var bounds := _world_bounds()
	if bounds.is_empty():
		return Vector2(32, 48)
	var columns := maxi(int(bounds[&"max_x"]) - int(bounds[&"min_x"]) + 1, 1)
	var rows := maxi(int(bounds[&"max_y"]) - int(bounds[&"min_y"]) + 1, 1)
	var available := (size - MAP_PADDING * 2.0).max(Vector2.ONE)
	var fit := minf(available.x / (columns * 16.0), available.y / (rows * 24.0))
	# Native 16px units use integer magnification. Large worlds can be viewed
	# at overview scale, then enlarged with the same invertible camera mapping.
	var pixel := maxf(floorf(fit), 1.0) if fit >= 1.0 else maxf(fit, 0.25)
	return (Vector2(16, 24) * pixel * zoom_level).round().max(Vector2(4, 6))


func _service(property_name: StringName) -> Variant:
	if _runtime == null or not _runtime is Object:
		return null
	for property: Dictionary in _runtime.get_property_list():
		if StringName(property.get(&"name", &"")) == property_name:
			return _runtime.get(property_name)
	return null


func _world_bounds() -> Dictionary:
	var world: Variant = _service(&"world_service")
	if world == null or not world.has_method(&"get_bounds"):
		return {}
	var result: Variant = world.call(&"get_bounds")
	if not result is Dictionary:
		return {}
	for key: StringName in [&"min_x", &"max_x", &"min_y", &"max_y"]:
		if not result.has(key) and not result.has(String(key)):
			return {}
	return {
		&"min_x": int(result.get(&"min_x", result.get("min_x", 0))),
		&"max_x": int(result.get(&"max_x", result.get("max_x", -1))),
		&"min_y": int(result.get(&"min_y", result.get("min_y", 0))),
		&"max_y": int(result.get(&"max_y", result.get("max_y", -1))),
	}