extends Node3D
##
## StudioMain - root bootstrap for MonkeyStudio.
##
## Builds the runtime scene tree in code so the whole app is one auditable
## script rather than a fragile binary .tscn. Scene tree created:
##
##   StudioMain (Node3D)
##   ├── WorldEnvironment        (mobile renderer settings)
##   ├── Sun (DirectionalLight3D)
##   ├── Camera3D                (touch_camera.gd)
##   ├── Geometry (Node3D)       <- user-created meshes live here
##   ├── Rig (Node3D)            <- Skeleton3D lives here
##   ├── Features (Node)         <- lazily-instantiated feature modules
##   └── UI (CanvasLayer)
##       └── (built by studio_ui.gd)
##

const TouchCameraScript := preload("res://scripts/studio/touch_camera.gd")
const StudioUIScript := preload("res://scripts/studio/studio_ui.gd")

var camera: Camera3D
var geometry: Node3D
var rig: Node3D
var feature_host: Node
var ui: CanvasLayer


func _ready() -> void:
	_build_environment()
	_build_lighting()
	_build_camera()
	geometry = _make_node("Geometry")
	rig = _make_node("Rig")
	feature_host = Node.new()
	feature_host.name = "Features"
	add_child(feature_host)
	FeatureRegistry.host = feature_host
	_build_ui()
	_spawn_starter_scene()
	_connect_signals()
	print("[StudioMain] ready. %d features available." % FeatureRegistry.feature_count())


func _build_environment() -> void:
	var env := Environment.new()
	env.background_mode = Environment.BG_COLOR
	env.background_color = Color(0.08, 0.09, 0.11)
	env.ambient_light_source = Environment.AMBIENT_SOURCE_COLOR
	env.ambient_light_color = Color(0.35, 0.38, 0.45)
	env.ambient_light_energy = 0.6
	# Mobile-friendly tonemap + no heavy SSAO/GI by default.
	env.tonemap_mode = Environment.TONE_MAPPER_FILMIC
	env.ssao_enabled = false
	env.glow_enabled = false
	var we := WorldEnvironment.new()
	we.name = "WorldEnvironment"
	we.environment = env
	add_child(we)


func _build_lighting() -> void:
	var sun := DirectionalLight3D.new()
	sun.name = "Sun"
	sun.rotation_degrees = Vector3(-50, -40, 0)
	sun.light_energy = 1.1
	sun.shadow_enabled = true
	# Lower shadow resolution on mobile to save bandwidth.
	sun.directional_shadow_max_distance = 40.0
	add_child(sun)


func _build_camera() -> void:
	camera = TouchCameraScript.new()
	camera.name = "Camera3D"
	camera.fov = 60.0
	camera.position = Vector3(4, 4, 8)
	add_child(camera)
	camera.focus = Vector3.ZERO


func _make_node(n: String) -> Node3D:
	var node := Node3D.new()
	node.name = n
	add_child(node)
	return node


func _build_ui() -> void:
	ui = StudioUIScript.new()
	ui.name = "UI"
	add_child(ui)


## Spawn a cube so the app is immediately interactive on first launch.
func _spawn_starter_scene() -> void:
	FeatureRegistry.activate("mesh.cube")
	var gen: Node = feature_host.get_node_or_null("Feature_mesh.cube")
	if gen != null and gen.has_method("spawn"):
		var mesh: MeshInstance3D = gen.call("spawn", "cube", {"size": 1.5})
		_ensure_collision(mesh)
		StudioBus.object_selected.emit(mesh)
		if camera != null:
			camera.frame_aabb(mesh.mesh.get_aabb())


## Give a mesh a static trimesh collider so sculpting raycasts hit it.
func _ensure_collision(mi: MeshInstance3D) -> void:
	if mi == null or mi.mesh == null:
		return
	var body := StaticBody3D.new()
	body.name = mi.name + "_Body"
	var shape := CollisionShape3D.new()
	var trimesh := mi.mesh.create_trimesh_shape()
	if trimesh != null:
		shape.shape = trimesh
	else:
		# Fallback to a box for exotic primitives without trimesh support.
		var box := BoxShape3D.new()
		box.size = mi.mesh.get_aabb().size
		shape.shape = box
	body.add_child(shape)
	mi.add_child(body)


func _connect_signals() -> void:
	StudioBus.fps_throttled.connect(_on_fps_throttled)
	MemoryManager.memory_warning.connect(_on_memory_warning)


func _on_fps_throttled(fps: int) -> void:
	# Shed load: disable shadows first, then reduce the sim substep budget.
	var sun := get_node_or_null("Sun") as DirectionalLight3D
	if sun != null and sun.shadow_enabled:
		sun.shadow_enabled = false
		print("[Perf] shadows off at %d fps" % fps)


func _on_memory_warning(used_mb: float, budget_mb: float) -> void:
	print("[Mem] warning: %.0f/%.0f MB" % [used_mb, budget_mb])