extends Node3D

## Weapon hold lab — tune how each character holds each gun, in 3D, live.
##
##   godot --path . res://debug/weapon_lab.tscn
##
## Every knob in the rifle hold started life as a constant tuned against one rig,
## and every one of them was wrong on the next character imported. The ones that
## CAN be derived from the skeleton now are — the mount rotation, the wrist roll,
## the weapon size. What is left is genuinely art direction: how high the stock
## rides, how far the elbow flares, how hard the fingers close. Those want an eye
## and a slider, not another guess in code.
##
## Pick a character, pick a weapon, pick a pose, drag the sliders, press Save.
## The result lands in assets/characters/weapon_holds.json keyed by character and
## weapon, and the game reads it whenever that gun is equipped.
##
## CONTROLS
##   left drag    orbit          wheel   zoom
##   middle drag  pan            F       frame the hands
##   R            reset knobs    S       save        C   copy JSON to clipboard
##
## The three coloured markers are the points being solved for — red is the
## trigger grip, green the support hand on the handguard, blue the buttstock. If
## a hand is not on its marker the IK could not reach, which is a different
## problem from the marker being in the wrong place.

const POSES := [
	["Low ready", "ground", 0.0, 0.0],
	["Aiming", "ground", 0.0, 1.0],
	["Running", "ground", 9.0, 0.0],
	["Crouched", "ground", 0.0, 0.0],
]

var _model: SkinnedPlayerModel
var _skins: Array = []
var _weapons: Array = []
var _skin := 0
var _weapon := 0
var _pose := 0
var _knobs: Dictionary = {}
var _all: Dictionary = {}
var _sliders: Dictionary = {}
var _status: Label
var _cam: Camera3D
var _yaw := 0.6
var _pitch := -0.1
var _dist := 2.2
var _pivot := Vector3(0, 1.25, 0)
var _markers: Array = []
var _pickers: Dictionary = {}


## Frames to wait before the self-shot below. The model loads asynchronously and
## the cloth solver needs a moment to settle, so an immediate capture shows a
## half-built character.
const SHOT_WARMUP := 40
var _shot_path := ""
var _frames := 0


func _ready() -> void:
	_build_world()
	_collect_sources()
	# `-- shot <path> [skin] [weapon]` renders one frame and quits, so the lab
	# can be checked without a human at the controls.
	var args := OS.get_cmdline_user_args()
	if args.size() >= 2 and String(args[0]) == "shot":
		_shot_path = String(args[1])
		if args.size() > 2:
			_skin = maxi(0, _index_of(_skins, String(args[2])))
		if args.size() > 3:
			_weapon = maxi(0, _index_of(_weapons, String(args[3])))
	_build_ui()
	_reload_model()


func _index_of(list: Array, id: String) -> int:
	for i in list.size():
		if String(list[i].id) == id:
			return i
	return -1


# ── scene ─────────────────────────────────────────────────────────────────────

func _build_world() -> void:
	var env := WorldEnvironment.new()
	var e := Environment.new()
	e.background_mode = Environment.BG_COLOR
	e.background_color = Color(0.17, 0.18, 0.22)
	e.ambient_light_source = Environment.AMBIENT_SOURCE_COLOR
	e.ambient_light_color = Color(0.55, 0.57, 0.65)
	e.ambient_light_energy = 1.0
	env.environment = e
	add_child(env)

	var key := DirectionalLight3D.new()
	key.rotation_degrees = Vector3(-42, 132, 0)
	key.light_energy = 1.5
	add_child(key)
	var fill := DirectionalLight3D.new()
	fill.rotation_degrees = Vector3(-18, -40, 0)
	fill.light_energy = 0.5
	add_child(fill)

	_cam = Camera3D.new()
	_cam.fov = 45.0
	add_child(_cam)
	_update_camera()

	# Grip / support / stock, so the points under the sliders are visible.
	for c in [Color(1, 0.3, 0.3), Color(0.3, 1, 0.4), Color(0.4, 0.6, 1)]:
		var m := MeshInstance3D.new()
		var sphere := SphereMesh.new()
		sphere.radius = 0.012
		sphere.height = 0.024
		m.mesh = sphere
		var mat := StandardMaterial3D.new()
		mat.albedo_color = c
		mat.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
		# Depth-tested on purpose. Drawn through the body they look like they are
		# floating in front of the chest when they are in fact behind an arm,
		# which is exactly the wrong impression for judging whether a hand is on
		# its target.
		mat.no_depth_test = false
		m.material_override = mat
		add_child(m)
		_markers.append(m)


func _collect_sources() -> void:
	for id in SkinManager.skins:
		var s = SkinManager.skins[id]
		# GLB-backed skins only; the colour tints have no skeleton to pose.
		if "model_path" in s and String(s.model_path) != "":
			_skins.append({"id": id, "name": s.skin_name, "path": s.model_path})
	_skins.sort_custom(func(a, b): return a.id < b.id)
	for id in LoadoutManager.weapon_db:
		var w: Dictionary = LoadoutManager.weapon_db[id]
		if String(w.get("script", "")) != "":
			_weapons.append({"id": id, "name": w.get("name", id),
				"script": w["script"]})
	_weapons.sort_custom(func(a, b): return a.id < b.id)
	_all = WeaponHoldTuning.load_all()


func _reload_model() -> void:
	if _model:
		_model.queue_free()
	_model = SkinnedPlayerModel.new()
	_model.model_path = _skins[_skin].path
	_model.skin_id = _skins[_skin].id
	add_child(_model)
	await get_tree().process_frame
	_load_knobs()
	_model.set_weapon(_weapons[_weapon].script)
	_model.set_hold_tuning(_knobs)
	_apply_pose()


func _apply_pose() -> void:
	if not _model or not _model.loaded:
		return
	var p: Array = POSES[_pose]
	_model.update_state(p[1], p[2], _pose == 3)
	_model.set_locomotion(0.0, 1.0 if p[2] > 0.1 else 0.0, p[3])


func _process(_delta: float) -> void:
	_apply_pose()
	if _shot_path != "":
		_frames += 1
		if _frames == SHOT_WARMUP:
			# Frame the hands, which is the only part anyone is judging.
			if _model and _model._pose_mod:
				_pivot = _model.skeleton.global_transform * _model._pose_mod.dbg_grip
				_dist = 0.7
				_yaw = 1.15
				_pitch = -0.15
				_update_camera()
		elif _frames > SHOT_WARMUP + 2:
			var img := get_viewport().get_texture().get_image()
			img.save_png(_shot_path)
			print("weapon_lab: saved ", _shot_path)
			get_tree().quit()
			return
	if _model and _model._pose_mod and _model.skeleton:
		var to_world: Transform3D = _model.skeleton.global_transform
		var pm = _model._pose_mod
		var pts := [pm.dbg_grip, pm.dbg_fore, pm.dbg_stock]
		for i in _markers.size():
			_markers[i].global_position = to_world * pts[i]
			_markers[i].visible = pts[i] != Vector3.ZERO


# ── knobs ─────────────────────────────────────────────────────────────────────

func _load_knobs() -> void:
	_knobs = WeaponHoldTuning.resolve(_all, _skins[_skin].id, _weapons[_weapon].id)
	for k in _sliders:
		var entry = _sliders[k]
		var spec: Array = entry.spec
		if spec[4]:
			var v: Vector3 = _knobs.get(k, WeaponHoldTuning.default_for(k))
			entry.x.set_value_no_signal(v.x)
			entry.y.set_value_no_signal(v.y)
			entry.z.set_value_no_signal(v.z)
		else:
			entry.x.set_value_no_signal(float(_knobs.get(k,
				WeaponHoldTuning.default_for(k))))
		_refresh_label(k)


func _knob_changed(key: String) -> void:
	var entry = _sliders[key]
	var spec: Array = entry.spec
	if spec[4]:
		_knobs[key] = Vector3(entry.x.value, entry.y.value, entry.z.value)
	else:
		_knobs[key] = entry.x.value
	_refresh_label(key)
	if _model:
		_model.set_hold_tuning(_knobs)


func _refresh_label(key: String) -> void:
	var entry = _sliders[key]
	var spec: Array = entry.spec
	if spec[4]:
		entry.label.text = "%s   %.3f, %.3f, %.3f" % [spec[1], entry.x.value,
			entry.y.value, entry.z.value]
	else:
		var v: float = entry.x.value
		entry.label.text = "%s   %s" % [spec[1],
			"auto" if (key == "weapon_scale" and v < 0.01) else "%.3f" % v]


# ── ui ────────────────────────────────────────────────────────────────────────

func _build_ui() -> void:
	var layer := CanvasLayer.new()
	add_child(layer)

	var panel := PanelContainer.new()
	panel.set_anchors_preset(Control.PRESET_LEFT_WIDE)
	panel.custom_minimum_size = Vector2(430, 0)
	layer.add_child(panel)

	var scroll := ScrollContainer.new()
	panel.add_child(scroll)
	var box := VBoxContainer.new()
	box.custom_minimum_size = Vector2(410, 0)
	box.add_theme_constant_override("separation", 2)
	scroll.add_child(box)

	var title := Label.new()
	title.text = "WEAPON HOLD LAB"
	box.add_child(title)

	box.add_child(_picker("Character", _skins, func(i):
		_skin = i
		_reload_model()))
	box.add_child(_picker("Weapon", _weapons, func(i):
		_weapon = i
		_load_knobs()
		if _model:
			_model.set_weapon(_weapons[_weapon].script)
			_model.set_hold_tuning(_knobs)))
	var poses: Array = []
	for p in POSES:
		poses.append({"name": p[0]})
	box.add_child(_picker("Pose", poses, func(i): _pose = i))

	box.add_child(HSeparator.new())
	for spec in WeaponHoldTuning.KNOBS:
		box.add_child(_knob_row(spec))

	box.add_child(HSeparator.new())
	var row := HBoxContainer.new()
	for b in [["Save (S)", func(): _save()], ["Reset (R)", func(): _reset()],
			["Copy JSON (C)", func(): _copy()]]:
		var btn := Button.new()
		btn.text = b[0]
		btn.pressed.connect(b[1])
		row.add_child(btn)
	box.add_child(row)

	_status = Label.new()
	_status.autowrap_mode = TextServer.AUTOWRAP_WORD_SMART
	_status.custom_minimum_size = Vector2(400, 40)
	_status.text = "left drag orbit  ·  wheel zoom  ·  middle drag pan  ·  F frame hands"
	box.add_child(_status)
	# Reflect whatever the shot arguments or the defaults selected, or the
	# dropdown says one thing while the scene shows another.
	_pickers["Character"].select(_skin)
	_pickers["Weapon"].select(_weapon)
	_pickers["Pose"].select(_pose)


func _picker(label: String, items: Array, on_pick: Callable) -> Control:
	var row := HBoxContainer.new()
	var l := Label.new()
	l.text = label
	l.custom_minimum_size = Vector2(90, 0)
	row.add_child(l)
	var opt := OptionButton.new()
	opt.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	for it in items:
		opt.add_item(String(it.name))
	opt.item_selected.connect(on_pick)
	row.add_child(opt)
	_pickers[label] = opt
	return row


func _knob_row(spec: Array) -> Control:
	var key: String = spec[0]
	var box := VBoxContainer.new()
	box.add_theme_constant_override("separation", 0)
	var label := Label.new()
	box.add_child(label)
	var entry := {"spec": spec, "label": label}
	var axes := ["x", "y", "z"] if spec[4] else ["x"]
	for a in axes:
		var sl := HSlider.new()
		sl.min_value = spec[2]
		sl.max_value = spec[3]
		sl.step = 0.001
		sl.custom_minimum_size = Vector2(400, 14)
		sl.value_changed.connect(func(_v): _knob_changed(key))
		box.add_child(sl)
		entry[a] = sl
	_sliders[key] = entry
	return box


func _save() -> void:
	var where := WeaponHoldTuning.save(_all, _skins[_skin].id,
		_weapons[_weapon].id, _knobs)
	_status.text = "Saved %s + %s to %s" % [_skins[_skin].id,
		_weapons[_weapon].id, where]


func _reset() -> void:
	_knobs.clear()
	for k in _sliders:
		var e = _sliders[k]
		for a in ["x", "y", "z"]:
			if e.has(a):
				e[a].set_value_no_signal(0.0)
		_refresh_label(k)
	if _model:
		_model.set_hold_tuning({})
	_status.text = "Reset to what the code derives"


func _copy() -> void:
	var flat := {}
	for k in _knobs:
		var v = _knobs[k]
		flat[k] = [v.x, v.y, v.z] if v is Vector3 else v
	DisplayServer.clipboard_set(JSON.stringify(flat, "  "))
	_status.text = "Copied this character+weapon's knobs to the clipboard"


# ── camera ────────────────────────────────────────────────────────────────────

func _update_camera() -> void:
	var b := Basis.from_euler(Vector3(_pitch, _yaw, 0))
	_cam.global_transform = Transform3D(b, _pivot + b * Vector3(0, 0, _dist))


func _unhandled_input(e: InputEvent) -> void:
	if e is InputEventMouseMotion:
		if e.button_mask & MOUSE_BUTTON_MASK_LEFT:
			_yaw -= e.relative.x * 0.006
			_pitch = clampf(_pitch - e.relative.y * 0.006, -1.4, 1.4)
			_update_camera()
		elif e.button_mask & MOUSE_BUTTON_MASK_MIDDLE:
			var b := _cam.global_transform.basis
			_pivot += (b.x * -e.relative.x + b.y * e.relative.y) * _dist * 0.0015
			_update_camera()
	elif e is InputEventMouseButton and e.pressed:
		if e.button_index == MOUSE_BUTTON_WHEEL_UP:
			_dist = maxf(_dist * 0.9, 0.15)
			_update_camera()
		elif e.button_index == MOUSE_BUTTON_WHEEL_DOWN:
			_dist = minf(_dist * 1.1, 8.0)
			_update_camera()
	elif e is InputEventKey and e.pressed and not e.echo:
		match e.keycode:
			KEY_F:
				# Frame the hands, which is what is actually being judged.
				if _model and _model._pose_mod:
					_pivot = _model.skeleton.global_transform \
						* _model._pose_mod.dbg_grip
					_dist = 0.55
					_update_camera()
			KEY_S: _save()
			KEY_R: _reset()
			KEY_C: _copy()
			KEY_ESCAPE: get_tree().quit()