extends Node3D

## VALIDATED APPROACH: Trellis-generated head attached to character via BoneAttachment3D.
##
## Result: head attaches correctly to the Head bone and follows animation.
## The BoneAttachment3D system works for static meshes riding single bones.
## This is the production path for per-character generated heads.
##
## Takes screenshots at multiple angles, then quits.

const ANIM_PATH := "res://models/quaternius/animations/UAL2_Standard.glb"
const CAM_DIST: float = 20.0
const PIVOT_Y_ZOOMED_OUT: float = 0.9
const PIVOT_Y_ZOOMED_IN: float = 1.5
const ZOOM_MIN: float = 1.5
const ZOOM_MAX: float = 30.0

var _camera: Camera3D
var _character: CharacterVisual
var _out_dir: String
var _shots: Array[Dictionary] = []
var _shot_index: int = 0
var _settle_frames: int = 0

func _ready() -> void:
	var git_output: Array = []
	OS.execute("git", ["rev-parse", "--show-toplevel"], git_output)
	var root := (git_output[0] as String).strip_edges()
	var timestamp := Time.get_datetime_string_from_system().replace(":", "").replace("T", "-").substr(0, 15)
	_out_dir = "%s/.tmp/head-smoke-%s" % [root, timestamp]
	DirAccess.make_dir_recursive_absolute(_out_dir)
	print("Output: %s" % _out_dir)

	_camera = Camera3D.new()
	_camera.projection = Camera3D.PROJECTION_ORTHOGONAL
	_camera.near = 0.1
	_camera.far = 100.0
	_camera.current = true
	add_child(_camera)

	_build_floor()
	_build_lighting()

	# Character with original Superhero body
	_character = CharacterVisual.new()
	_character.set_shaders(
		preload("res://shaders/spike/toon.gdshader"),
		preload("res://shaders/spike/toon_masked.gdshader"),
		preload("res://shaders/spike/outline.gdshader"),
	)
	_character.position = Vector3(0.0, 0.04, 0.0)
	_character.rotation_degrees.y = 45.0
	add_child(_character)

	_character.load_unsegmented_body("res://models/quaternius/base-characters/Superhero_Male_FullBody.gltf")
	var anims := _character.load_animation_library(ANIM_PATH)
	for anim_name in anims:
		if "Idle" in anim_name:
			_character.play_animation(anim_name)
			break

	# Attach Trellis head
	var ok := _character.attach_to_bone("res://models/generated/head.glb", "Head")
	print("Head attached: %s" % ok)

	# Build shots: with/without head, different angles and zooms
	var angles := {
		"dramatic": Vector3(-30.0, 45.0, 0.0),
		"frontal": Vector3(-5.0, 45.0, 0.0),
	}
	var zooms := {"gameplay": 5.0, "heavy": 2.5}

	# With Trellis head
	for angle_name in angles:
		for zoom_name in zooms:
			_shots.append({
				"name": "head-on_%s_%s" % [angle_name, zoom_name],
				"angle": angles[angle_name],
				"zoom": zooms[zoom_name],
				"head": true,
			})

	# Without head (baseline comparison)
	_shots.append({
		"name": "head-off_dramatic_gameplay",
		"angle": angles["dramatic"],
		"zoom": 5.0,
		"head": false,
	})
	_shots.append({
		"name": "head-off_frontal_heavy",
		"angle": angles["frontal"],
		"zoom": 2.5,
		"head": false,
	})

	_setup_shot(_shots[0])
	print("Smoke test: %d shots" % _shots.size())

func _process(_delta: float) -> void:
	if _shot_index >= _shots.size():
		print("Smoke test complete")
		get_tree().quit()
		return

	_settle_frames += 1
	if _settle_frames < 15:
		return

	var img := get_viewport().get_texture().get_image()
	var filename := "%02d-%s.png" % [_shot_index + 1, _shots[_shot_index]["name"]]
	img.save_png(_out_dir.path_join(filename))
	print("  [%d/%d] %s" % [_shot_index + 1, _shots.size(), filename])

	_shot_index += 1
	if _shot_index < _shots.size():
		_setup_shot(_shots[_shot_index])
		_settle_frames = 0

func _setup_shot(shot: Dictionary) -> void:
	if shot["head"]:
		if not _character.has_bone_attachments():
			_character.attach_to_bone("res://models/generated/head.glb", "Head")
	else:
		_character.detach_all_bone_attachments()

	var zoom := float(shot["zoom"])
	_camera.size = zoom
	var zoom_t := 1.0 - (zoom - ZOOM_MIN) / (ZOOM_MAX - ZOOM_MIN)
	var pivot_y := lerpf(PIVOT_Y_ZOOMED_OUT, PIVOT_Y_ZOOMED_IN, clampf(zoom_t, 0.0, 1.0))
	var pivot := Vector3(0.0, pivot_y, 0.0)
	var rot := shot["angle"] as Vector3
	_camera.rotation_degrees = rot
	var basis := Basis.from_euler(rot * (PI / 180.0))
	_camera.position = pivot + basis * Vector3(0, 0, CAM_DIST)

func _build_floor() -> void:
	for x in range(-4, 5):
		for z in range(-4, 5):
			var mi := MeshInstance3D.new()
			var quad := PlaneMesh.new()
			quad.size = Vector2(0.95, 0.95)
			mi.mesh = quad
			mi.position = Vector3(float(x), 0.0, float(z))
			var mat := StandardMaterial3D.new()
			mat.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
			if (abs(x) + abs(z)) % 2 == 0:
				mat.albedo_color = Color(0.35, 0.38, 0.42)
			else:
				mat.albedo_color = Color(0.28, 0.30, 0.34)
			mi.material_override = mat
			add_child(mi)

func _build_lighting() -> void:
	var light := DirectionalLight3D.new()
	light.transform = Transform3D(
		Basis(Vector3(0.866, -0.354, 0.354), Vector3(0, 0.707, 0.707), Vector3(-0.5, -0.612, 0.612)),
		Vector3(5, 10, 5)
	)
	light.light_energy = 0.8
	add_child(light)

	var env := Environment.new()
	env.background_mode = Environment.BG_COLOR
	env.background_color = Color(0.18, 0.2, 0.24)
	env.ambient_light_source = Environment.AMBIENT_SOURCE_COLOR
	env.ambient_light_color = Color(0.5, 0.5, 0.55)
	env.ambient_light_energy = 0.6
	var world_env := WorldEnvironment.new()
	world_env.environment = env
	add_child(world_env)