# model_render_test —— 不启动游戏、不连服务器的模型渲染自动回归。
#
#   godot --path project --script model_render_test.gd
#   godot --path project --script model_render_test.gd -- --race 0
#   godot --path project --script model_render_test.gd -- --bless   # 重建基线
#
# 与 char_bench_test.gd 的区别：bench 只产图、判定靠人眼；这里对渲染结果算数值
# 指标并断言，退出码即结论。覆盖范围仅限「离线装配的单角色」——没有地图、没有
# 光照环境的真实动态、没有 40250 像素比对，因此它不能替代 gamescene_visual_test
# 和导出包验收，只用来挡住模型/发型/材质改动引入的回归。
#
# 指标（每个 race）：
#   feet_gap_m       最低蒙皮顶点到 y=0 的距离（悬空/陷地）
#   silhouette_px    正面剪影像素数（模型是否真的画出来了）
#   hair_mean_lum    只画发型时，发型像素的平均亮度（多余高光会把它抬上去）
#   hair_mean_lum_ctrl  同上，但换回旧的 StandardMaterial3D(roughness=1) —— 负对照，
#                    用来证明这个指标现在仍然分得开好坏，而不是恒过
#   head_cover       full 与 no_hair 在近景机位的差异像素占比（发型遮挡量）
#
# 绝对断言不依赖基线；head_cover / silhouette_px 这类因模型而异的量对比
# test/rendering/model_baseline.json。改模型或改光照后用 --bless 重建基线，
# 并在计划书执行记录里写清为什么重建。
extends SceneTree

const PlayerView = preload("res://ui/player_view.gd")
const BASELINE := "res://../test/rendering/model_baseline.json"

# 渲染尺寸：指标在 GDScript 里逐像素统计，512 是精度和耗时的折中。
const SIZE := 512
const BG := Color(1, 0, 1)          # 洋红背景，模型不会出现这个颜色

# --- 绝对阈值（不依赖基线）------------------------------------------------
# 脚底：bench 无地形，模型自带 ground_offset，实测四职业 |gap| <= 0.003 m。
const FEET_GAP_MAX := 0.03
# 剪影：正面 512x512 里角色至少占这么多像素，防止「什么都没画」也算过。
const SILHOUETTE_MIN := 3000
# 发型高光用「发型像素的平均亮度」度量。发色本身明暗差别很大（武士近黑、
# 修罗银白），所以没有跨职业通用的绝对上限：绝对判定只用下面的负对照差，
# 具体数值按职业记进基线。旧材质相对新材质的实测抬升是 +0.011 ~ +0.037
# （八个职业，见 test/rendering/README.md）。
const LUM_BRIGHT := 0.20    # hair_lum_p99 只作参考量，不参与判定
# 负对照必须比生产材质亮这么多，否则说明这条指标已经不分好坏了（例如有人把
# 灯光调暗，两边都测不出高光）。八职业最小实测差 0.0109。
const HAIR_CTRL_MARGIN := 0.008

# --- 基线容差 -------------------------------------------------------------
const TOL_HEAD_COVER := 0.03        # 绝对
const TOL_SILHOUETTE := 0.03        # 相对
const TOL_HAIR_LUM := 0.006         # 绝对；最小的「旧材质」信号是 0.0109

var _out := ""
var _bless := false
var _fail: Array[String] = []

func _initialize() -> void:
	call_deferred("run")

func _arg(name: String, dflt := "") -> String:
	var args := OS.get_cmdline_user_args()
	var i := args.find("--" + name)
	return args[i + 1] if i >= 0 and i + 1 < args.size() else dflt

func run() -> void:
	root.size = Vector2i(SIZE, SIZE)
	_bless = "--bless" in OS.get_cmdline_user_args()
	_out = OS.get_environment("MT_RENDER_OUTPUT")
	if _out.is_empty():
		_out = ProjectSettings.globalize_path("res://../build/rendering/modeltest-%d"
				% Time.get_unix_time_from_system())
	DirAccess.make_dir_recursive_absolute(_out)

	var races: Array = []
	var only := _arg("race")
	if only.is_empty():
		races = [0, 1, 2, 3, 4, 5, 6, 7]
	else:
		races = [int(only)]

	var baseline := _load_baseline()
	var results := {}
	_light()
	var cam := Camera3D.new()
	cam.near = 0.02
	root.add_child(cam)
	cam.make_current()

	for race in races:
		var m := await _measure(int(race), cam)
		if m.is_empty():
			_fail.append("race %d: build failed" % race)
			continue
		results[str(race)] = m
		_check_absolute(int(race), m)
		if not _bless:
			_check_baseline(int(race), m, baseline)

	var report := {
		"passed": _fail.is_empty(),
		"failures": _fail,
		"blessed": _bless,
		"races": results,
		"thresholds": {
			"feet_gap_max": FEET_GAP_MAX, "silhouette_min": SILHOUETTE_MIN,
			"hair_ctrl_margin": HAIR_CTRL_MARGIN, "tol_hair_lum": TOL_HAIR_LUM,
			"tol_head_cover": TOL_HEAD_COVER, "tol_silhouette": TOL_SILHOUETTE,
		},
		"engine": Engine.get_version_info(),
		"viewport": str(root.size),
		"assets": AssetRoot.path(),
		"headless": DisplayServer.get_name() == "headless",
		"scope": "offline single-actor assembly; no map, no network, no 40250 pixel parity",
		"sha256": {"res://bin/libmtgodot.macos.template_debug.dylib":
				FileAccess.get_sha256("res://bin/libmtgodot.macos.template_debug.dylib"),
			"res://model_render_test.gd": FileAccess.get_sha256("res://model_render_test.gd")},
	}
	var f := FileAccess.open(_out.path_join("report.json"), FileAccess.WRITE)
	f.store_string(JSON.stringify(report, "\t"))
	f.close()
	if _bless:
		_write_baseline(results)
		print("MODELRENDER: baseline written -> ", ProjectSettings.globalize_path(BASELINE))
	print("MODELRENDER: ", _out)
	print(JSON.stringify(report))
	for msg in _fail:
		printerr("MODELRENDER FAIL: ", msg)
	print("MODELRENDER: ", "PASS" if _fail.is_empty() else "FAIL")
	quit(0 if _fail.is_empty() else 1)

# --- 单个 race 的测量 -----------------------------------------------------

func _measure(race: int, cam: Camera3D) -> Dictionary:
	var pv := PlayerView.new()
	root.add_child(pv)
	if not pv.build(AssetRoot.path(), race):
		pv.queue_free()
		return {}
	pv.set_anim_state("wait")
	await process_frame
	await process_frame
	if pv.anim:
		pv.anim.call("set_time", 0.5)
		pv.anim.set_process(false)
	pv.rotation = Vector3.ZERO
	await process_frame

	var body: MeshInstance3D = null
	for mi in pv.find_children("*", "MeshInstance3D", true, false):
		if mi.name == "MeshInstance3D":
			body = mi
	if body == null or body.mesh == null:
		pv.queue_free()
		return {}
	var total := body.mesh.get_surface_count()
	var base_mats: Array = []
	for s in total:
		base_mats.append(body.get_surface_override_material(s))
	var hair_first := _hair_surface_first(pv, body, total)

	# 脚底：最低蒙皮顶点（bench 里地面就是 y=0）
	var feet_y := INF
	for mi in pv.find_children("*", "MeshInstance3D", true, false):
		if mi.mesh:
			feet_y = minf(feet_y, (mi.global_transform * mi.get_aabb()).position.y)

	var m := {
		"body_gr2": String(pv.model.get("gr2_path")),
		"hair_gr2": String(pv.model.get("hair_gr2")),
		"surfaces": total, "hair_surface_first": hair_first,
		"feet_gap_m": feet_y if is_finite(feet_y) else NAN,
	}

	# 1) 正面剪影
	_aim(cam, Vector3(0, 1.0, 3.1), Vector3(0, 0.9, 0), 40.0)
	var front := await _grab("race%d-front" % race)
	m["silhouette_px"] = _count_fg(front)

	# 2) 近景：full / no_hair 的差异 = 发型遮挡量
	_aim(cam, Vector3(0.75, 1.68, 0.05), Vector3(0, 1.62, 0), 32.0)
	var full := await _grab("race%d-face_side" % race)
	if hair_first >= 0:
		for s in range(hair_first, total):
			body.set_surface_override_material(s, _hidden())
	var nohair := await _grab("race%d-face_side-no_hair" % race)
	_restore(body, base_mats)
	var fg := _count_fg(nohair)
	m["head_cover"] = (float(_count_diff(full, nohair)) / float(maxi(fg, 1))) if hair_first >= 0 else 0.0
	m["head_px"] = fg

	# 3) 发型亮度：只画发型，量 99 分位亮度；再用旧材质做负对照
	if hair_first >= 0:
		for s in range(0, hair_first):
			body.set_surface_override_material(s, _hidden())
		var hair_only := await _grab("race%d-hair_only" % race)
		var hs := _lum_stats(hair_only)
		m["hair_lum_p99"] = hs["p99"]
		m["hair_bright_frac"] = hs["bright_frac"]
		m["hair_mean_lum"] = hs["mean"]
		var legacy := _legacy_hair_material(base_mats[hair_first])
		for s in range(hair_first, total):
			body.set_surface_override_material(s, legacy)
		var ctrl := await _grab("race%d-hair_only-legacy_ctrl" % race)
		var cs := _lum_stats(ctrl)
		m["hair_lum_ctrl"] = cs["p99"]
		m["hair_bright_frac_ctrl"] = cs["bright_frac"]
		m["hair_mean_lum_ctrl"] = cs["mean"]
		_restore(body, base_mats)
	else:
		m["hair_lum_p99"] = 0.0
		m["hair_lum_ctrl"] = 0.0
		m["hair_bright_frac"] = 0.0
		m["hair_bright_frac_ctrl"] = 0.0
		m["hair_mean_lum"] = 0.0
		m["hair_mean_lum_ctrl"] = 0.0

	pv.queue_free()
	await process_frame
	return m

# --- 断言 -----------------------------------------------------------------

func _check_absolute(race: int, m: Dictionary) -> void:
	var gap: float = m["feet_gap_m"]
	if not is_finite(gap) or absf(gap) > FEET_GAP_MAX:
		_fail.append("race %d: feet_gap_m=%s exceeds %.3f" % [race, gap, FEET_GAP_MAX])
	if int(m["silhouette_px"]) < SILHOUETTE_MIN:
		_fail.append("race %d: silhouette_px=%d below %d" % [race, int(m["silhouette_px"]), SILHOUETTE_MIN])
	if int(m["hair_surface_first"]) < 0:
		return
	var margin: float = float(m["hair_mean_lum_ctrl"]) - float(m["hair_mean_lum"])
	if margin < HAIR_CTRL_MARGIN:
		_fail.append(("race %d: legacy control only %.4f above production; " % [race, margin])
				+ "hair_mean_lum no longer discriminates")

func _check_baseline(race: int, m: Dictionary, baseline: Dictionary) -> void:
	var key := str(race)
	if not baseline.has(key):
		_fail.append("race %d: no baseline entry (run with --bless after reviewing the render)" % race)
		return
	var b: Dictionary = baseline[key]
	var cover_delta: float = absf(float(m["head_cover"]) - float(b.get("head_cover", 0.0)))
	if cover_delta > TOL_HEAD_COVER:
		_fail.append("race %d: head_cover %.4f vs baseline %.4f (delta %.4f > %.3f)"
				% [race, float(m["head_cover"]), float(b.get("head_cover", 0.0)), cover_delta, TOL_HEAD_COVER])
	var base_px: float = float(b.get("silhouette_px", 0.0))
	if base_px > 0.0:
		var rel: float = absf(float(m["silhouette_px"]) - base_px) / base_px
		if rel > TOL_SILHOUETTE:
			_fail.append("race %d: silhouette_px %d vs baseline %d (%.1f%% > %.1f%%)"
					% [race, int(m["silhouette_px"]), int(base_px), rel * 100.0, TOL_SILHOUETTE * 100.0])
	var lum_delta: float = absf(float(m["hair_mean_lum"]) - float(b.get("hair_mean_lum", 0.0)))
	if lum_delta > TOL_HAIR_LUM:
		_fail.append("race %d: hair_mean_lum %.4f vs baseline %.4f (delta %.4f > %.4f)"
				% [race, float(m["hair_mean_lum"]), float(b.get("hair_mean_lum", 0.0)),
				lum_delta, TOL_HAIR_LUM])

# --- 像素统计 -------------------------------------------------------------
# get_pixel 逐点调用在 512x512 上太慢，直接读 RGBA8 字节。

func _fg_mask(img: Image) -> PackedByteArray:
	var d := img.get_data()
	var n := img.get_width() * img.get_height()
	var mask := PackedByteArray()
	mask.resize(n)
	for i in n:
		var o := i * 4
		# 背景是纯洋红；模型不会出现 R 高 / G 近 0 / B 高 的组合
		mask[i] = 0 if (d[o] > 240 and d[o + 1] < 24 and d[o + 2] > 240) else 1
	return mask

func _count_fg(img: Image) -> int:
	var mask := _fg_mask(img)
	var c := 0
	for v in mask:
		c += v
	return c

# 「发型盖住了脑袋多少」：只数 no_hair 里属于人体的像素中被 full 改写的那些，
# 不含发型溢出到背景的部分（那属于轮廓，不是遮挡）。
func _count_diff(a: Image, b: Image) -> int:
	var da := a.get_data()
	var db := b.get_data()
	var n := mini(da.size(), db.size()) / 4
	var c := 0
	for i in n:
		var o := i * 4
		var br := int(db[o]); var bg := int(db[o + 1]); var bb := int(db[o + 2])
		if br > 240 and bg < 24 and bb > 240:
			continue        # no_hair 里是背景 —— 不算遮挡
		if absi(int(da[o]) - br) > 12 or absi(int(da[o + 1]) - bg) > 12 \
				or absi(int(da[o + 2]) - bb) > 12:
			c += 1
	return c

# 前景像素亮度统计（256 桶直方图）。返回 {p99, bright_frac, mean}。
# 判定用 mean：它对「整片发型被额外高光抬亮」最敏感，且不受发色基准影响
# （基准差异由按职业的基线吸收）。p99/bright_frac 只写进报告备查。
func _lum_stats(img: Image) -> Dictionary:
	var d := img.get_data()
	var n := img.get_width() * img.get_height()
	var hist := PackedInt32Array()
	hist.resize(256)
	var total := 0
	for i in n:
		var o := i * 4
		var r := int(d[o]); var g := int(d[o + 1]); var bl := int(d[o + 2])
		if r > 240 and g < 24 and bl > 240:
			continue
		var lum := int((0.2126 * float(r) + 0.7152 * float(g) + 0.0722 * float(bl)))
		hist[clampi(lum, 0, 255)] += 1
		total += 1
	if total == 0:
		return {"p99": 0.0, "bright_frac": 0.0, "mean": 0.0}
	var cut := int(float(total) * 0.99)
	var acc := 0
	var p99 := 1.0
	for v in 256:
		acc += hist[v]
		if acc >= cut:
			p99 = float(v) / 255.0
			break
	var bright := 0
	var sum := 0
	for v in 256:
		sum += hist[v] * v
		if v >= int(LUM_BRIGHT * 255.0):
			bright += hist[v]
	return {"p99": p99, "bright_frac": float(bright) / float(total),
		"mean": float(sum) / float(total) / 255.0}

# --- 场景辅助 -------------------------------------------------------------

func _aim(cam: Camera3D, eye: Vector3, at: Vector3, fov: float) -> void:
	cam.global_transform = Transform3D(Basis(), eye).looking_at(at, Vector3.UP)
	cam.fov = fov

func _grab(name: String) -> Image:
	await RenderingServer.frame_post_draw
	await RenderingServer.frame_post_draw
	var img := root.get_texture().get_image()
	img.convert(Image.FORMAT_RGBA8)
	img.save_png(_out.path_join(name + ".png"))
	return img

func _light() -> void:
	var sun := DirectionalLight3D.new()
	sun.rotation_degrees = Vector3(-42, 155, 0)
	sun.light_energy = 1.1
	sun.set_layer_mask(0xFFFFF)
	root.add_child(sun)
	var env := WorldEnvironment.new()
	var e := Environment.new()
	e.background_mode = Environment.BG_COLOR
	e.background_color = BG
	e.ambient_light_source = Environment.AMBIENT_SOURCE_COLOR
	e.ambient_light_color = Color(0.6, 0.62, 0.68)
	e.ambient_light_energy = 0.8
	env.environment = e
	root.add_child(env)

func _hidden() -> StandardMaterial3D:
	var m := StandardMaterial3D.new()
	m.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	m.albedo_color = Color(0, 0, 0, 0)
	m.no_depth_test = false
	m.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	return m

func _restore(body: MeshInstance3D, base_mats: Array) -> void:
	for s in base_mats.size():
		body.set_surface_override_material(s, base_mats[s])

# 负对照：R2-02 修复前 _load_hair() 用的那一套。
func _legacy_hair_material(production: Material) -> StandardMaterial3D:
	var m := StandardMaterial3D.new()
	m.roughness = 1.0
	m.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA_SCISSOR
	m.alpha_scissor_threshold = 0.5
	m.cull_mode = BaseMaterial3D.CULL_DISABLED
	if production is ShaderMaterial:
		var tex = (production as ShaderMaterial).get_shader_parameter("albedo_tex")
		if tex != null:
			m.albedo_texture = tex
	return m

# 发型折在 body mesh 尾部；get_info() 报的 surfaces= 是身体自己的 surface 数。
func _hair_surface_first(pv: Node3D, body: MeshInstance3D, total: int) -> int:
	if String(pv.model.get("hair_gr2")).is_empty():
		return -1
	var info := String(pv.model.call("get_info"))
	var body_surfaces := -1
	for token in info.split(" ", false):
		if token.begins_with("surfaces="):
			body_surfaces = int(token.substr(9))
	if body_surfaces <= 0 or body_surfaces >= total:
		return -1
	return body_surfaces

# --- 基线读写 -------------------------------------------------------------

func _load_baseline() -> Dictionary:
	if not FileAccess.file_exists(BASELINE):
		return {}
	var txt := FileAccess.get_file_as_string(BASELINE)
	var parsed = JSON.parse_string(txt)
	return parsed.get("races", {}) if parsed is Dictionary else {}

func _write_baseline(results: Dictionary) -> void:
	var slim := {}
	for k in results:
		var m: Dictionary = results[k]
		slim[k] = {"body_gr2": String(m["body_gr2"]).get_file(),
			"hair_gr2": String(m["hair_gr2"]).get_file(),
			"head_cover": m["head_cover"], "silhouette_px": m["silhouette_px"],
			"head_px": m["head_px"], "hair_mean_lum": m["hair_mean_lum"],
			"hair_mean_lum_ctrl": m["hair_mean_lum_ctrl"],
			"hair_lum_p99": m["hair_lum_p99"], "hair_bright_frac": m["hair_bright_frac"]}
	DirAccess.make_dir_recursive_absolute(ProjectSettings.globalize_path(BASELINE).get_base_dir())
	var f := FileAccess.open(BASELINE, FileAccess.WRITE)
	f.store_string(JSON.stringify({
		"note": "godot --path project --script model_render_test.gd -- --bless",
		"engine": Engine.get_version_info()["string"],
		"races": slim}, "\t"))
	f.close()