extends SceneTree

## Does the escape menu's character picker actually work?
##
## It is built entirely in code, in an autoload, over a paused tree — three
## things that each hide their own class of mistake and none of which a compile
## check catches. So: open it, walk every entry, and assert that each one
## selects, describes itself, and builds a real model with a real skeleton.
##
##     godot --headless --path . -s res://debug/character_picker_check.gd

var _fails: int = 0

func _init() -> void:
	root.call_deferred("add_child", Node.new())  # let autoloads finish _ready
	await process_frame
	await process_frame

	var menu = root.get_node_or_null("PauseMenu")
	_check(menu != null, "PauseMenu autoload exists")
	if menu == null:
		_done()
		return

	_check(menu.character_btn != null, "Character button exists on the pause menu")
	_check(menu.character_list != null, "Character list exists")
	_check(menu.character_editor != null, "Character screen exists")

	menu._show_character()
	await process_frame
	_check(menu.character_editor.visible, "Character screen shows")
	_check(not menu.main_vbox.visible, "Main pause list hides behind it")

	# Autoload singletons are not resolvable as identifiers from a `-s` SceneTree
	# script — it is compiled before they register — so reach it by path.
	var skin_mgr = root.get_node("SkinManager")

	var count: int = menu.character_list.item_count
	_check(count > 0, "Roster is not empty (%d entries)" % count)

	var seen_glb := 0
	for i in count:
		var id: String = menu.character_list.get_item_metadata(i)
		menu._on_character_selected(i)
		await process_frame
		await process_frame
		_check(menu.character_desc.text != "", "'%s' has a description line" % id)

		var skin = skin_mgr.get_skin(id)
		var expects_model: bool = skin.model_path != "" \
			and ResourceLoader.exists(skin.model_path)
		if not expects_model:
			# A colour-tint skin has no GLB. The preview must be EMPTY, not the
			# previously selected character left standing there.
			_check(menu._preview_model == null,
				"'%s' is a colour skin and clears the preview" % id)
			continue
		seen_glb += 1
		var model = menu._preview_model
		_check(model != null, "'%s' builds a preview model" % id)
		if model == null:
			continue
		_check(model.loaded, "'%s' preview finished loading" % id)
		_check(model.skeleton != null, "'%s' preview has a skeleton" % id)
		_check(model.animation_player != null, "'%s' preview has animations" % id)
		_check(model.surface_table() != null and not model.surface_table().is_empty(),
			"'%s' preview knows its surface classes" % id)
		var body: Array = model.surfaces_of(SkinSurfaces.BODY)
		_check(not body.is_empty(), "'%s' preview reports body surfaces" % id)
		# A preview that is not ANIMATING is a preview of the bind pose, which
		# is the one pose the character will never be in during play. The clip
		# NAME is not evidence of that — it is a variable this class sets on
		# itself, and it reads "Idle" just as happily when the animation tree
		# is not ticking at all. So watch the skeleton move.
		_check(model.current_clip_debug() == "Idle",
			"'%s' preview selected Idle (got '%s')"
				% [id, model.current_clip_debug()])
		_check(await _pose_moves(model),
			"'%s' preview skeleton is actually animating" % id)

	_check(seen_glb >= 6, "every shipping GLB skin previewed (%d)" % seen_glb)

	# Back out, and make sure the turntable stops costing frames.
	menu._show_main_menu()
	await process_frame
	_check(not menu.character_editor.visible, "Back returns to the pause list")
	_check(menu.main_vbox.visible, "Pause list is showing again")

	_done()


## Does the skeleton's pose change over a handful of frames?
##
## Sampled from INSIDE the modifier pass would be better, but the question here
## is only "is anything driving this at all", and for that the animated pose is
## the right thing to read: if the AnimationTree is not ticking, every bone
## holds still and this returns false.
func _pose_moves(model) -> bool:
	var skel: Skeleton3D = model.skeleton
	if skel == null or skel.get_bone_count() == 0:
		return false
	var before: Array = []
	for b in skel.get_bone_count():
		before.append(skel.get_bone_pose_rotation(b))
	for _i in 12:
		await process_frame
	for b in skel.get_bone_count():
		if not skel.get_bone_pose_rotation(b).is_equal_approx(before[b]):
			return true
	return false


func _check(ok: bool, what: String) -> void:
	if ok:
		print("  OK: %s" % what)
	else:
		print("  FAIL: %s" % what)
		_fails += 1


func _done() -> void:
	print("\n=== CHARACTER PICKER ===\nFailures: %d" % _fails)
	quit(1 if _fails > 0 else 0)