extends SceneTree
## Generates the placeholder avatar asset pack (GLB files) referenced by
## assets/avatars/catalog.json.
##
## These are deliberately crude primitive stand-ins so the avatar loader /
## customization / in-world rendering can be built and tested now; real art
## swaps in later as a pure content change (catalog paths are unchanged).
##
## The base body is a Roblox-classic (R6) style blocky figure: six chunky box
## parts (head, torso, two arms, two legs) skinned one-part-per-bone onto the
## 24-bone canonical rig, arms hanging at the sides, plus a painted-on face.
##
## Run:  godot --headless --path . --script res://scripts/tools/gen_placeholder_avatars.gd
## Output: res://assets/avatars/*.glb  (13 attachments + 1 rigged base body)

const OUT_DIR := "res://assets/avatars/"

# Canonical rig -- must match avatar_loader.gd CANONICAL_BONES. Each entry:
#   name -> [parent_name, global_rest_position]  (A-pose, arms down, Y-up, metres)
#   The character faces -Z (Godot's node "forward"), so the face, toes and
#   front-mounted attachments live at negative Z.
const BONES := {
	"Root":          ["",              Vector3(0.00, 0.00, 0.00)],
	"Hips":          ["Root",          Vector3(0.00, 0.76, 0.00)],
	"Spine":         ["Hips",          Vector3(0.00, 1.00, 0.00)],
	"Chest":         ["Spine",         Vector3(0.00, 1.30, 0.00)],
	"Neck":          ["Chest",         Vector3(0.00, 1.50, 0.00)],
	"Head":          ["Neck",          Vector3(0.00, 1.58, 0.00)],
	"HeadTop":       ["Head",          Vector3(0.00, 2.00, 0.00)],
	"Jaw":           ["Head",          Vector3(0.00, 1.64, -0.16)],
	"LeftEye":       ["Head",          Vector3(0.12, 1.76, -0.27)],
	"RightEye":      ["Head",          Vector3(-0.12, 1.76, -0.27)],
	"LeftShoulder":  ["Chest",         Vector3(0.42, 1.50, 0.00)],
	"LeftUpperArm":  ["LeftShoulder",  Vector3(0.60, 1.44, 0.00)],
	"LeftLowerArm":  ["LeftUpperArm",  Vector3(0.60, 1.14, 0.00)],
	"LeftHand":      ["LeftLowerArm",  Vector3(0.60, 0.82, 0.00)],
	"RightShoulder": ["Chest",         Vector3(-0.42, 1.50, 0.00)],
	"RightUpperArm": ["RightShoulder", Vector3(-0.60, 1.44, 0.00)],
	"RightLowerArm": ["RightUpperArm", Vector3(-0.60, 1.14, 0.00)],
	"RightHand":     ["RightLowerArm", Vector3(-0.60, 0.82, 0.00)],
	"LeftUpperLeg":  ["Hips",          Vector3(0.21, 0.74, 0.00)],
	"LeftLowerLeg":  ["LeftUpperLeg",  Vector3(0.21, 0.38, 0.00)],
	"LeftFoot":      ["LeftLowerLeg",  Vector3(0.21, 0.05, -0.06)],
	"RightUpperLeg": ["Hips",          Vector3(-0.21, 0.74, 0.00)],
	"RightLowerLeg": ["RightUpperLeg", Vector3(-0.21, 0.38, 0.00)],
	"RightFoot":     ["RightLowerLeg", Vector3(-0.21, 0.05, -0.06)],
}

# Order matters: parents before children.
const BONE_ORDER := [
	"Root", "Hips", "Spine", "Chest", "Neck", "Head", "HeadTop", "Jaw",
	"LeftEye", "RightEye",
	"LeftShoulder", "LeftUpperArm", "LeftLowerArm", "LeftHand",
	"RightShoulder", "RightUpperArm", "RightLowerArm", "RightHand",
	"LeftUpperLeg", "LeftLowerLeg", "LeftFoot",
	"RightUpperLeg", "RightLowerLeg", "RightFoot",
]

# Roblox-classic colour blocks.
const C_SKIN  := Color(0.96, 0.80, 0.19)   # bright yellow  (head + arms)
const C_SHIRT := Color(0.05, 0.41, 0.67)   # bright blue    (torso)
const C_PANTS := Color(0.18, 0.49, 0.30)   # bright green   (legs)
const C_FACE  := Color(0.05, 0.05, 0.06)   # near-black     (eyes + smile)

# Body parts: [bone, centre, size, colour].  Each part is one rigid box, fully
# weighted to its bone -- so the rig still drives it, but it reads as a clean
# solid block (no banding, no capsule taper).
const PARTS := [
	# Torso, arms and legs all share the same 0.46 depth so a limb always fully
	# covers the slice of torso behind it -- otherwise a brightly-lit sliver of
	# the torso side peeks past the arm and reads as a cyan seam.
	["Head",          Vector3(0.00, 1.74, 0.00), Vector3(0.58, 0.56, 0.58), C_SKIN],
	["Spine",         Vector3(0.00, 1.14, 0.00), Vector3(0.90, 0.80, 0.46), C_SHIRT],
	["LeftUpperArm",  Vector3(0.57, 1.14, 0.00), Vector3(0.34, 0.78, 0.46), C_SKIN],
	["RightUpperArm", Vector3(-0.57, 1.14, 0.00), Vector3(0.34, 0.78, 0.46), C_SKIN],
	["LeftUpperLeg",  Vector3(0.21, 0.38, 0.00), Vector3(0.40, 0.78, 0.46), C_PANTS],
	["RightUpperLeg", Vector3(-0.21, 0.38, 0.00), Vector3(0.40, 0.78, 0.46), C_PANTS],
	# painted-on face -- thin plates on the front of the head (-Z), rigged to Head
	["Head",          Vector3(0.13, 1.78, -0.30), Vector3(0.09, 0.12, 0.02), C_FACE],
	["Head",          Vector3(-0.13, 1.78, -0.30), Vector3(0.09, 0.12, 0.02), C_FACE],
	["Head",          Vector3(0.00, 1.64, -0.30), Vector3(0.32, 0.05, 0.02), C_FACE],
]

# Attachments: id -> [Mesh, local_offset_from_mount_bone, colour]
# Mesh is built in _attachment_mesh().
const ATTACHMENTS := {
	"head_cyber_01":       ["head",     Vector3(0, 0.04, 0.0),   Color(0.20, 0.85, 0.95)],
	"hair_mohawk_01":      ["mohawk",   Vector3(0, 0.0, 0.0),    Color(0.90, 0.20, 0.35)],
	"hair_ponytail_01":    ["ponytail", Vector3(0, -0.06, 0.16), Color(0.45, 0.30, 0.15)],
	"face_glasses_01":     ["glasses",  Vector3(0, 0.12, -0.16), Color(0.10, 0.10, 0.12)],
	"chest_bandit_01":     ["torso",    Vector3(0, -0.12, 0.0),  Color(0.55, 0.20, 0.20)],
	"back_backpack_01":    ["box",      Vector3(0, -0.06, 0.28), Color(0.30, 0.35, 0.25)],
	"pants_cargo_01":      ["hips",     Vector3(0, -0.04, 0.0),  Color(0.30, 0.35, 0.45)],
	"left_hand_glove_01":  ["blob",     Vector3(0, 0.0, 0.0),    Color(0.15, 0.15, 0.18)],
	"right_hand_glove_01": ["blob",     Vector3(0, 0.0, 0.0),    Color(0.15, 0.15, 0.18)],
	"left_foot_boot_01":   ["boot",     Vector3(0, -0.02, -0.05), Color(0.12, 0.10, 0.09)],
	"right_foot_boot_01":  ["boot",     Vector3(0, -0.02, -0.05), Color(0.12, 0.10, 0.09)],
	"accessory_belt_01":   ["belt",     Vector3(0, 0.74, 0.0),   Color(0.20, 0.18, 0.12)],
	"accessory_necklace_01": ["necklace", Vector3(0, 1.34, -0.10), Color(0.85, 0.75, 0.20)],
}

var _fail := 0


func _initialize() -> void:
	var abs_dir := ProjectSettings.globalize_path(OUT_DIR)
	DirAccess.make_dir_recursive_absolute(abs_dir)

	_gen_base_body()
	for id in ATTACHMENTS:
		var spec: Array = ATTACHMENTS[id]
		_gen_attachment(id, spec[0], spec[1], spec[2])

	print("\n%s" % ("DONE — all placeholder avatar GLBs written" if _fail == 0
		else "FAILED (%d errors)" % _fail))
	quit(_fail)


# ---------------------------------------------------------------------------
# Base body -- rigged, skinned
# ---------------------------------------------------------------------------

func _global_rest(bone: String) -> Transform3D:
	return Transform3D(Basis.IDENTITY, BONES[bone][1])


func _gen_base_body() -> void:
	var root := Node3D.new()
	root.name = "AvatarRoot"

	var skel := Skeleton3D.new()
	skel.name = "Skeleton3D"
	root.add_child(skel)

	var idx := {}
	for bone in BONE_ORDER:
		var i := skel.add_bone(bone)
		idx[bone] = i
	for bone in BONE_ORDER:
		var parent: String = BONES[bone][0]
		var g := _global_rest(bone)
		if parent == "":
			skel.set_bone_rest(idx[bone], g)
		else:
			skel.set_bone_parent(idx[bone], idx[parent])
			skel.set_bone_rest(idx[bone], _global_rest(parent).affine_inverse() * g)
	for bone in BONE_ORDER:
		skel.set_bone_pose_position(idx[bone], skel.get_bone_rest(idx[bone]).origin)

	# Skin: one bind per bone, bind pose = inverse global rest.
	var skin := Skin.new()
	for bone in BONE_ORDER:
		skin.add_named_bind(bone, _global_rest(bone).affine_inverse())

	var bind_index := {}
	for b in range(BONE_ORDER.size()):
		bind_index[BONE_ORDER[b]] = b

	# One surface per distinct colour so parts stay flat-shaded solids.
	var groups: Dictionary = {}   # Color (as key string) -> {color, verts, normals, bones, weights}
	for part in PARTS:
		var bone: String = part[0]
		var centre: Vector3 = part[1]
		var size: Vector3 = part[2]
		var col: Color = part[3]
		var key := col.to_html()
		if not groups.has(key):
			groups[key] = {
				"color": col,
				"verts": PackedVector3Array(),
				"normals": PackedVector3Array(),
				"bones": PackedInt32Array(),
				"weights": PackedFloat32Array(),
			}
		var gg = groups[key]
		_append_box(gg.verts, gg.normals, gg.bones, gg.weights,
			centre, size, bind_index[bone])

	var mesh := ArrayMesh.new()
	var surf := 0
	for key in groups:
		var gg = groups[key]
		var arr := []
		arr.resize(Mesh.ARRAY_MAX)
		arr[Mesh.ARRAY_VERTEX] = gg.verts
		arr[Mesh.ARRAY_NORMAL] = gg.normals
		arr[Mesh.ARRAY_BONES] = gg.bones
		arr[Mesh.ARRAY_WEIGHTS] = gg.weights
		mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, arr)
		var mat := StandardMaterial3D.new()
		mat.albedo_color = gg.color
		mat.roughness = 0.9
		mesh.surface_set_material(surf, mat)
		surf += 1

	var mi := MeshInstance3D.new()
	mi.name = "Body"
	mi.mesh = mesh
	mi.skin = skin
	skel.add_child(mi)
	mi.skeleton = mi.get_path_to(skel)

	_write_glb(root, "base_human_male_01")
	root.free()


# Append an axis-aligned box (centre, size) with every vert weighted 1.0 to bone_idx.
func _append_box(verts: PackedVector3Array, normals: PackedVector3Array,
		bones: PackedInt32Array, weights: PackedFloat32Array,
		centre: Vector3, size: Vector3, bone_idx: int) -> void:
	var h := size * 0.5
	# 8 corners
	var c: Array[Vector3] = [
		centre + Vector3(-h.x, -h.y, -h.z), centre + Vector3(h.x, -h.y, -h.z),
		centre + Vector3(h.x, -h.y, h.z),   centre + Vector3(-h.x, -h.y, h.z),
		centre + Vector3(-h.x, h.y, -h.z),  centre + Vector3(h.x, h.y, -h.z),
		centre + Vector3(h.x, h.y, h.z),    centre + Vector3(-h.x, h.y, h.z),
	]
	# Vertex order per face is CCW seen from outside -> the computed normal
	# points outward. (Getting this backwards renders the whole mesh as an
	# inside-out black shell: every face is lit from behind.)
	var faces := [
		[3, 2, 6, 7],   # +Z front
		[1, 0, 4, 5],   # -Z back
		[7, 6, 5, 4],   # +Y top
		[0, 1, 2, 3],   # -Y bottom
		[2, 1, 5, 6],   # +X right
		[3, 7, 4, 0],   # -X left
	]
	for f in faces:
		var q: Array[Vector3] = [c[f[0]], c[f[1]], c[f[2]], c[f[3]]]
		var n: Vector3 = (q[1] - q[0]).cross(q[2] - q[0]).normalized()
		for tri in [[0, 1, 2], [0, 2, 3]]:
			for vi in tri:
				verts.append(q[vi])
				normals.append(n)
				bones.append_array([bone_idx, 0, 0, 0])
				weights.append_array([1.0, 0.0, 0.0, 0.0])


# ---------------------------------------------------------------------------
# Attachments -- plain static meshes
# ---------------------------------------------------------------------------

func _gen_attachment(id: String, kind: String, offset: Vector3, col: Color) -> void:
	var root := Node3D.new()
	root.name = "AttachmentRoot"
	var mi := MeshInstance3D.new()
	mi.name = id
	mi.mesh = _attachment_mesh(kind)
	mi.position = offset
	var mat := StandardMaterial3D.new()
	mat.albedo_color = col
	mat.roughness = 0.9
	mi.material_override = mat
	root.add_child(mi)
	_write_glb(root, id)
	root.free()


func _attachment_mesh(kind: String) -> Mesh:
	match kind:
		"head":
			var m := BoxMesh.new(); m.size = Vector3(0.60, 0.56, 0.56); return m
		"mohawk":
			var m := PrismMesh.new(); m.size = Vector3(0.08, 0.20, 0.44); return m
		"ponytail":
			var m := BoxMesh.new(); m.size = Vector3(0.14, 0.30, 0.16); return m
		"glasses":
			var m := BoxMesh.new(); m.size = Vector3(0.44, 0.10, 0.03); return m
		"torso":
			var m := BoxMesh.new(); m.size = Vector3(0.80, 0.66, 0.42); return m
		"box":
			var m := BoxMesh.new(); m.size = Vector3(0.34, 0.40, 0.16); return m
		"hips":
			var m := BoxMesh.new(); m.size = Vector3(0.66, 0.34, 0.40); return m
		"blob":
			var m := BoxMesh.new(); m.size = Vector3(0.30, 0.24, 0.34); return m
		"boot":
			var m := BoxMesh.new(); m.size = Vector3(0.34, 0.16, 0.42); return m
		"belt":
			var m := TorusMesh.new(); m.inner_radius = 0.22; m.outer_radius = 0.30; return m
		"necklace":
			var m := TorusMesh.new(); m.inner_radius = 0.10; m.outer_radius = 0.14; return m
		_:
			return BoxMesh.new()


# ---------------------------------------------------------------------------
# GLB export
# ---------------------------------------------------------------------------

func _write_glb(scene_root: Node, basename: String) -> void:
	# append_from_scene needs the node in a tree.
	get_root().add_child(scene_root)
	var doc := GLTFDocument.new()
	var state := GLTFState.new()
	var err := doc.append_from_scene(scene_root, state)
	if err != OK:
		push_error("append_from_scene failed for %s: %s" % [basename, error_string(err)])
		_fail += 1
		get_root().remove_child(scene_root)
		return
	var out_path := ProjectSettings.globalize_path("%s%s.glb" % [OUT_DIR, basename])
	err = doc.write_to_filesystem(state, out_path)
	get_root().remove_child(scene_root)
	if err != OK:
		push_error("write_to_filesystem failed for %s: %s" % [basename, error_string(err)])
		_fail += 1
		return
	print("  wrote %s.glb (%d bytes)" % [basename, FileAccess.get_file_as_bytes(out_path).size()])