class_name ArenaBoundary
extends StaticBody3D

# The standard arena play volume (inner faces of the enclosure). Every arena
# instances objects/arena_boundary.tscn so all arenas share one size; code
# that needs field dimensions derives them from these constants rather than
# restating numbers.
const INNER_HALF_X := 12.0
const INNER_HALF_Z := 18.0
const INNER_HEIGHT := 12.0
# Goal-centre distance from arena centre; the end walls sit 1 m behind, so a
# ball pinned against them still overlaps the goal sensor.
const GOAL_LINE_Z := 17.0

@onready var _wall_pos_x: MeshInstance3D = $WallPosXMesh
@onready var _wall_neg_x: MeshInstance3D = $WallNegXMesh
@onready var _wall_pos_z: MeshInstance3D = $WallPosZMesh
@onready var _wall_neg_z: MeshInstance3D = $WallNegZMesh
@onready var _ceiling: MeshInstance3D = $CeilingMesh


func _process(_delta: float) -> void:
	# The translucent field material tints everything behind it, so any face
	# the camera has crossed to the outside of is hidden entirely — looking
	# into the arena from outside stays clear, while faces seen from inside
	# keep their tint. Collision is untouched; only the meshes toggle.
	var camera := get_viewport().get_camera_3d()
	if camera == null:
		return  # headless (RL/CI) has no camera
	var p := to_local(camera.global_position)
	_wall_pos_x.visible = p.x < INNER_HALF_X
	_wall_neg_x.visible = p.x > -INNER_HALF_X
	_wall_pos_z.visible = p.z < INNER_HALF_Z
	_wall_neg_z.visible = p.z > -INNER_HALF_Z
	_ceiling.visible = p.y < INNER_HEIGHT