extends Node
##
## SelfTest - headless verification of every core subsystem.
## Run:  godot --headless res://tests/self_test.tscn
##
## Exits with code 0 if all checks pass, 1 otherwise. This is the regression
## gate for the modules; it does not need a display or GPU.
##

var _failures := 0
var _host: Node3D


func _ready() -> void:
	_host = Node3D.new()
	_host.name = "TestHost"
	var geom := Node3D.new()
	geom.name = "Geometry"
	_host.add_child(geom)
	var rig := Node3D.new()
	rig.name = "Rig"
	_host.add_child(rig)
	add_child(_host)

	_test_memory_manager()
	_test_mesh_generators()
	_test_sculpt()
	_test_rigging()
	_test_simulation()
	_test_timeline()

	print("")
	if _failures == 0:
		print("SELFTEST: ALL PASS")
		get_tree().quit(0)
	else:
		print("SELFTEST: %d FAILURE(S)" % _failures)
		get_tree().quit(1)


func _check(name: String, cond: bool) -> void:
	if cond:
		print("  [PASS] ", name)
	else:
		_failures += 1
		print("  [FAIL] ", name)


func _test_memory_manager() -> void:
	print("[Test] MemoryManager")
	_check("budget set", MemoryManager.asset_budget_mb > 0.0)
	_check("feature count >= 20", FeatureRegistry.feature_count() >= 20)
	var snap := MemoryManager.debug_snapshot()
	_check("snapshot has budget", snap.has("budget_mb"))


func _load_module(path: String) -> Node:
	var script: GDScript = load(path)
	var n: Node = script.new()
	_host.add_child(n)
	if n.has_method("_activate"):
		n.call("_activate", _host)
	return n


func _test_mesh_generators() -> void:
	print("[Test] Mesh generators")
	var mg := _load_module("res://scripts/modules/mesh_gen.gd")
	for kind in ["cube", "sphere", "cylinder", "plane", "torus", "ico", "suzanne"]:
		var data: Dictionary = mg.call("generate", kind, {})
		var vcount: int = (data["verts"] as PackedVector3Array).size()
		var icount: int = (data["indices"] as PackedInt32Array).size()
		_check("%s has verts & tris (v=%d,i=%d)" % [kind, vcount, icount], vcount > 0 and icount > 0)
	var mi: MeshInstance3D = mg.call("spawn", "sphere", {"radius": 1.0})
	_check("spawn returns MeshInstance3D", mi != null and mi.mesh != null and mi.mesh.get_surface_count() == 1)
	var cost := VertexBufferManager.estimate_cost_mb(1000)
	_check("cost estimate > 0", cost > 0.0)
	mg.queue_free()


func _test_sculpt() -> void:
	print("[Test] Sculpting")
	var mg := _load_module("res://scripts/modules/mesh_gen.gd")
	var sc := _load_module("res://scripts/modules/sculpt.gd")
	var mi: MeshInstance3D = mg.call("spawn", "sphere", {"radius": 1.0})
	sc.call("set_target", mi)
	var before: PackedVector3Array = (mi.mesh.surface_get_arrays(0)[Mesh.ARRAY_VERTEX] as PackedVector3Array).duplicate()
	for brush in ["draw", "grab", "pinch", "smooth", "flatten"]:
		sc.set("_brush_id", brush)
		sc.call("begin", Vector3(0, 1, 0))
		sc.call("apply", Vector3(0, 1, 0), Vector3(0, 0.1, 0))
		sc.call("apply", Vector3(0, 1, 0), Vector3(0.05, 0.1, 0))
		sc.call("end")
	var after: PackedVector3Array = mi.mesh.surface_get_arrays(0)[Mesh.ARRAY_VERTEX]
	var changed := false
	for i in range(mini(before.size(), after.size())):
		if before[i].distance_to(after[i]) > 0.0001:
			changed = true
			break
	_check("sculpt modified vertices", changed)
	_check("mesh still valid after sculpt", mi.mesh.get_surface_count() == 1)
	mg.queue_free()
	sc.queue_free()


func _test_rigging() -> void:
	print("[Test] Rigging")
	var mg := _load_module("res://scripts/modules/mesh_gen.gd")
	var rg := _load_module("res://scripts/modules/rigging.gd")
	var mi: MeshInstance3D = mg.call("spawn", "cube", {"size": 1.0})
	rg.call("generate_default_armature", mi)
	_check("bones created", int(rg.call("bone_count")) >= 9)
	_check("mesh has skin", mi.skin != null)
	_check("mesh has skeleton path", mi.skeleton != NodePath())
	if mi.mesh.get_surface_count() > 0:
		var arr: Array = mi.mesh.surface_get_arrays(0)
		_check("bones channel present", arr[Mesh.ARRAY_BONES] != null)
		_check("weights channel present", arr[Mesh.ARRAY_WEIGHTS] != null)
	mg.queue_free()
	rg.queue_free()


func _test_simulation() -> void:
	print("[Test] Simulation")
	var sim := _load_module("res://scripts/modules/simulation.gd")
	sim.call("create_cloth", "sim.cloth", 6, 6, 1.0)
	var before: PackedVector3Array = (sim.get("_sims")["sim.cloth"]["particles"] as PackedVector3Array).duplicate()
	for i in range(30):
		sim.call("_step", sim.get("_sims")["sim.cloth"])
	sim.call("_upload", sim.get("_sims")["sim.cloth"])
	var after: PackedVector3Array = sim.get("_sims")["sim.cloth"]["particles"]
	var moved := false
	for i in range(after.size()):
		if before[i].distance_to(after[i]) > 0.0001:
			moved = true
			break
	_check("cloth fell under gravity", moved)
	var mesh: ArrayMesh = sim.get("_sims")["sim.cloth"]["mesh"]
	_check("cloth mesh uploaded", mesh.get_surface_count() == 1)
	sim.call("create_hair", "sim.hair", 4, 5)
	_check("hair sim created", int(sim.call("active_sim_count")) >= 2)
	sim.queue_free()


func _test_timeline() -> void:
	print("[Test] Timeline")
	var mg := _load_module("res://scripts/modules/mesh_gen.gd")
	var tl := _load_module("res://scripts/modules/timeline.gd")
	var mi: MeshInstance3D = mg.call("spawn", "cube", {"size": 1.0})
	tl.call("add_keyframe", mi, "position", 0.0, Vector3.ZERO)
	tl.call("add_keyframe", mi, "position", 1.0, Vector3(0, 2, 0))
	_check("track created", int(tl.call("track_count")) >= 1)
	_check("key count == 2", int(tl.call("key_count")) == 2)
	tl.call("scrub", 0.5)
	_check("scrub clamps/works", absf(float(tl.call("playhead")) - 0.5) < 0.001)
	mg.queue_free()
	tl.queue_free()