extends Node3D
## The reusable game shell: player, camera, HUD and the PS1 filter — everything that
## outlives a single level. On load it instances the active level's module (geometry,
## spawners, lighting, colliders) into LevelRoot. Switching levels frees the whole
## previous module first, so no old mesh or collider can survive into the next fight.

const PhysicsLayers = preload("res://physics_layers.gd")

@onready var _level_root: Node3D = $LevelRoot
@onready var _camera: IsoCamera = $Player/Camera3D


func _ready() -> void:
	Run.ensure_run()
	load_active_level()


## Tear down the current level module and build the run's active one. Freeing the whole
## subtree (not hiding it) is the point: a level's colliders and spawners cease to exist
## before the next level's are created.
func load_active_level() -> void:
	for child: Node in _level_root.get_children():
		_level_root.remove_child(child)
		child.queue_free()
	var level := Run.active_level()
	if level == null or level.level_scene == null:
		push_warning("game_shell: active level has no level_scene")
		return
	_camera.set_framing_scale(level.camera_zoom)
	var module := level.level_scene.instantiate()
	_tag_environment_for_corpses(module)
	_level_root.add_child(module)


## Ground and walls stay on WORLD so the bull and live matadors collide with them; here
## we add CORPSE too. A killed matador's ragdoll is masked to CORPSE alone, so it rests
## on the arena while the bull — which only collides with WORLD — passes through the body
## instead of spazzing out on it. Done at load so it also reaches colliders baked into
## the instanced GLB arenas, not just the level module's own floor box.
func _tag_environment_for_corpses(module: Node) -> void:
	for body: StaticBody3D in module.find_children("*", "StaticBody3D", true, false):
		body.collision_layer |= PhysicsLayers.CORPSE