# EffectPlayer (P5) —— 解析后的 `.mse` spec → Godot 节点树（GPUParticles3D 为主）。
#
#   var fx := preload("res://fx/effect_player.gd").new()
#   fx.build(spec, assets_root)      # spec 来自 fx/mse.gd
#   add_child(fx)                    # 挂到要出特效的位置（可 reparent 到骨骼）
#   fx.play()                        # 或 fx.play(true) 一次性
#
# 覆盖 Particle 组：发射形状 / 速率 / 寿命 / 方向 / 重力 / 缩放曲线 / 颜色渐变 /
# billboard / 加法混合 / 旋转。纹理（.dds）暂用程序化径向渐变代替（GDScript 不解 DDS）。
# Mesh 组：占位（MeshFileName 是 .mde，另需解码器）。SimpleLight：本资产集未用。
extends Node3D

var spec := {}
var assets_root := ""
var one_shot := false
var _emitters: Array[GPUParticles3D] = []
var _mesh_nodes: Array[Node3D] = []
var _bsphere_r := 0.0

static var _glow_tex: Texture2D

func build(mse_spec: Dictionary, assets := "") -> void:
	spec = mse_spec
	assets_root = assets
	_bsphere_r = float(spec.get("bsphere_r", 0.0))
	for p in spec.get("particles", []):
		var e := _build_particle(p)
		if e:
			add_child(e)
			_emitters.append(e)
	for m in spec.get("meshes", []):
		var mn := _build_mesh(m)
		if mn:
			add_child(mn)
			_mesh_nodes.append(mn)

func play(force_one_shot := false) -> void:
	for i in _emitters.size():
		var e := _emitters[i]
		var st := float(_emitters[i].get_meta("start_time", 0.0))
		if force_one_shot:
			e.one_shot = true
		var tree := get_tree()
		if st <= 0.0 or tree == null:
			e.restart()
			e.emitting = true
		else:
			tree.create_timer(st).timeout.connect(func():
				if is_instance_valid(e):
					e.restart()
					e.emitting = true)
	var tr := get_tree()
	if (force_one_shot or one_shot) and tr:
		var total := _longest_life() + 0.5
		tr.create_timer(maxf(total, 1.5)).timeout.connect(queue_free)

func stop() -> void:
	for e in _emitters:
		e.emitting = false

func _longest_life() -> float:
	var m := 1.0
	for e in _emitters:
		m = maxf(m, e.lifetime + float(e.get_meta("start_time", 0.0)))
	return m

# --- particle ---------------------------------------------------------

func _build_particle(p: Dictionary) -> GPUParticles3D:
	var emit: Dictionary = p.get("emitter", {})
	var prop: Dictionary = p.get("particle", {})
	var g := GPUParticles3D.new()
	g.set_meta("start_time", float(p.get("start_time", 0.0)))
	g.amount = maxi(1, int(_n(emit.get("MaxEmissionCount", 16))))
	g.explosiveness = 0.0

	var life := _last_val(emit.get("TimeEventLifeTime", []), 1.0)
	g.lifetime = clampf(life, 0.05, 12.0)
	var cycle := _n(emit.get("CycleLength", 0.0))
	var loop := int(_n(emit.get("CycleLoopEnable", 0)))
	g.one_shot = (loop == 0)
	if cycle > 0.0 and loop != 0:
		g.lifetime = maxf(g.lifetime, cycle)

	var pm := ParticleProcessMaterial.new()
	# 发射形状
	var shape := int(_n(emit.get("EmitterShape", 0)))
	if shape == 3:
		pm.emission_shape = ParticleProcessMaterial.EMISSION_SHAPE_SPHERE
		pm.emission_sphere_radius = maxf(0.01, _n(emit.get("EmittingRadius", 10.0)) * 0.01)
	else:
		pm.emission_shape = ParticleProcessMaterial.EMISSION_SHAPE_POINT
	# 方向 / 速度
	var vel := _last_val(emit.get("TimeEventEmittingVelocity", []), 0.0) * 0.01
	pm.direction = Vector3(0, 1, 0)
	pm.spread = 25.0
	pm.initial_velocity_min = vel * 0.6
	pm.initial_velocity_max = maxf(vel, 0.05)
	# 重力
	var grav := _last_val(p.get("particle", {}).get("TimeEventGravity", []), 0.0)
	pm.gravity = Vector3(0, -grav * 0.01, 0)
	# 大小
	var sx := _last_val(emit.get("TimeEventSizeX", []), 32.0) * 0.01
	pm.scale_min = maxf(0.02, sx * 0.7)
	pm.scale_max = maxf(0.03, sx)
	pm.scale_curve = _curve_tex(prop.get("TimeEventScaleX", [[0, 1], [1, 0]]))
	# 颜色渐变（RGB 曲线各取末值 + Alpha 曲线）
	pm.color = _rgb(prop)
	var ramp := _alpha_ramp(prop.get("TimeEventAlpha", []), pm.color)
	if ramp:
		pm.color_ramp = ramp
	# 旋转
	var rspeed := _n(prop.get("RotationSpeed", 0.0))
	if rspeed != 0.0:
		pm.angular_velocity_min = deg_to_rad(rspeed) * 0.3
		pm.angular_velocity_max = deg_to_rad(rspeed)
	g.process_material = pm

	# 绘制网格 + 材质（billboard + 混合）
	var qm := QuadMesh.new()
	qm.size = Vector2(1, 1)
	g.draw_pass_1 = qm
	var mat := StandardMaterial3D.new()
	mat.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	mat.billboard_mode = _billboard(int(_n(prop.get("BillboardType", 1))))
	mat.billboard_keep_scale = true
	mat.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	mat.blend_mode = _blend(int(_n(prop.get("SrcBlendType", 5))), int(_n(prop.get("DestBlendType", 2))))
	mat.albedo_texture = _glow()
	mat.vertex_color_use_as_albedo = true
	g.material_override = mat
	return g

func _build_mesh(m: Dictionary) -> Node3D:
	# .mde 需要专门解码器；先占位一个小 box，位置对
	var n := Node3D.new()
	n.name = "mesh_" + String(m.get("mesh_file", "?")).get_basename()
	var mi := MeshInstance3D.new()
	var bm := BoxMesh.new()
	bm.size = Vector3(0.1, 0.1, 0.4)
	mi.mesh = bm
	var mat := StandardMaterial3D.new()
	mat.albedo_color = Color(1, 0.9, 0.5, 0.6)
	mat.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	mi.material_override = mat
	n.add_child(mi)
	return n

# --- helpers ---------------------------------------------------------

func _n(v) -> float:
	if v is Array:
		return float(v[0]) if v.size() > 0 else 0.0
	if v is float or v is int:
		return float(v)
	return 0.0

# List 表末行的值（列 idx，默认 col 1 = 时间后第一个数）
func _last_val(rows, def: float, col := 1) -> float:
	if rows is Array and rows.size() > 0:
		var r = rows[-1]
		if r is Array and r.size() > col and (r[col] is float or r[col] is int):
			return float(r[col])
	return def

func _rgb(prop: Dictionary) -> Color:
	return Color(
		_last_val(prop.get("TimeEventColorRed", []), 1.0),
		_last_val(prop.get("TimeEventColorGreen", []), 1.0),
		_last_val(prop.get("TimeEventColorBlue", []), 1.0),
		1.0)

# TimeEventScaleX rows [[t,v],...] -> CurveTexture
func _curve_tex(rows) -> CurveTexture:
	var c := Curve.new()
	c.min_value = 0.0
	c.max_value = 2.0
	if rows is Array and rows.size() > 0:
		for r in rows:
			if r is Array and r.size() >= 2:
				c.add_point(Vector2(clampf(float(r[0]), 0, 1), float(r[1])))
	else:
		c.add_point(Vector2(0, 1))
		c.add_point(Vector2(1, 0))
	var t := CurveTexture.new()
	t.curve = c
	return t

func _alpha_ramp(rows, base: Color) -> GradientTexture1D:
	if not (rows is Array) or rows.size() < 1:
		return null
	var grad := Gradient.new()
	grad.offsets = PackedFloat32Array()
	grad.colors = PackedColorArray()
	var pts := []
	for r in rows:
		if r is Array and r.size() >= 2:
			pts.append([clampf(float(r[0]), 0, 1), float(r[1])])
	if pts.is_empty():
		return null
	pts.sort_custom(func(a, b): return a[0] < b[0])
	if pts[0][0] > 0.0:
		pts.push_front([0.0, pts[0][1]])
	if pts[-1][0] < 1.0:
		pts.append([1.0, pts[-1][1]])
	for pt in pts:
		grad.add_point(pt[0], Color(base.r, base.g, base.b, clampf(pt[1], 0, 1)))
	grad.remove_point(0)
	grad.remove_point(0)
	var gt := GradientTexture1D.new()
	gt.gradient = grad
	return gt

func _billboard(bt: int) -> int:
	# 0 = none/local, 1 = 面向相机, 4 = Y 轴
	if bt == 4:
		return BaseMaterial3D.BILLBOARD_FIXED_Y
	if bt == 0:
		return BaseMaterial3D.BILLBOARD_DISABLED
	return BaseMaterial3D.BILLBOARD_ENABLED

func _blend(src: int, dst: int) -> int:
	# D3D blend: 5=SRCALPHA 2=ONE 4=INVSRCALPHA 3=SRCCOLOR
	if dst == 2:
		return BaseMaterial3D.BLEND_MODE_ADD
	if dst == 4:
		return BaseMaterial3D.BLEND_MODE_MIX
	return BaseMaterial3D.BLEND_MODE_ADD

# 程序化径向渐变（代替 .dds 粒子纹理）
static func _glow() -> Texture2D:
	if _glow_tex == null:
		var s := 48
		var img := Image.create(s, s, false, Image.FORMAT_RGBA8)
		for y in s:
			for x in s:
				var d := Vector2(x - s / 2.0, y - s / 2.0).length() / (s / 2.0)
				var a := clampf(1.0 - d, 0.0, 1.0)
				a = a * a
				img.set_pixel(x, y, Color(1, 1, 1, a))
		_glow_tex = ImageTexture.create_from_image(img)
	return _glow_tex