# VERTICAL SLICE - NOT FOR PRODUCTION
# 实现 GDD：design/ux/battle.md（D 区演出层——清图金粒喷泉+彩纸 3–5s 占位、Boss 紫赤影子爬棋盘
# 一次性占位、完美排雷金光带+横幅占位、标中旗加重弹道占位；全部程序化色板原语，真实美术归 战斗表现）。
# Date: 2026-09-12
# 高内聚边界：纯演出——组合根按核心信号调用 play_*；本类零核心依赖、不自持游戏状态。
class_name BoardFxView
extends Control

const COL_GOLD := UiKit.GOLD
const COL_BOSS := UiKit.BOSS_PURPLE         # 紫赤 #8F2F6A
const COL_FLAG := UiKit.FLAG_RED            # 旗朱
const CONFETTI_COLS := [UiKit.GOLD, UiKit.FLAG_RED, UiKit.HERO_BLUE, UiKit.WARM]

var _banner: Label


func _init() -> void:
	mouse_filter = Control.MOUSE_FILTER_IGNORE
	set_anchors_preset(Control.PRESET_FULL_RECT)
	_banner = UiKit.label("", 26, true)
	_banner.add_theme_color_override("font_color", COL_GOLD)
	_banner.set_anchors_preset(Control.PRESET_CENTER_TOP)
	_banner.grow_horizontal = Control.GROW_DIRECTION_BOTH
	_banner.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	_banner.visible = false
	_banner.mouse_filter = Control.MOUSE_FILTER_IGNORE
	add_child(_banner)


# 清图瞬间：金粒喷泉 + 彩纸 3–5s 即收（§2.3 占位）
func play_clear_burst() -> void:
	var fountain := CPUParticles2D.new()
	fountain.position = size * 0.5
	fountain.amount = 90
	fountain.lifetime = UiKit.motion(1.6)
	fountain.one_shot = true
	fountain.explosiveness = 0.2
	fountain.direction = Vector2(0, -1)
	fountain.spread = 55.0
	fountain.initial_velocity_min = 320.0
	fountain.initial_velocity_max = 560.0
	fountain.gravity = Vector2(0, 700)
	fountain.scale_amount_min = 2.0
	fountain.scale_amount_max = 4.5
	fountain.color = COL_GOLD
	fountain.emitting = true
	add_child(fountain)
	var confetti := CPUParticles2D.new()
	confetti.position = Vector2(size.x * 0.5, -8.0)
	confetti.amount = 60
	confetti.lifetime = UiKit.motion(3.2)
	confetti.one_shot = true
	confetti.explosiveness = 0.9
	confetti.direction = Vector2(0, 1)
	confetti.spread = 75.0
	confetti.initial_velocity_min = 90.0
	confetti.initial_velocity_max = 200.0
	confetti.gravity = Vector2(0, 140)
	confetti.scale_amount_min = 3.0
	confetti.scale_amount_max = 5.0
	confetti.color_ramp = _confetti_ramp()
	confetti.emitting = true
	add_child(confetti)
	var tw := create_tween()
	tw.tween_interval(UiKit.motion(3.5))
	tw.tween_callback(func():
		for n in [fountain, confetti]:
			if is_instance_valid(n):
				n.queue_free())


func _confetti_ramp() -> Gradient:
	var g := Gradient.new()
	g.set_color(0, CONFETTI_COLS[0])
	g.set_color(1, CONFETTI_COLS[1])
	return g


# Boss 遭遇：紫赤影子爬过棋盘一次性占位演出（§2.6）
func play_boss_shadow() -> void:
	var shadow := ColorRect.new()
	shadow.color = Color(COL_BOSS, 0.55)
	shadow.size = Vector2(size.x, 56.0)
	shadow.position = Vector2(0, -60.0)
	shadow.mouse_filter = Control.MOUSE_FILTER_IGNORE
	add_child(shadow)
	var tw := shadow.create_tween()
	tw.tween_property(shadow, "position:y", size.y, UiKit.motion(1.1)).set_trans(Tween.TRANS_SINE)
	tw.tween_property(shadow, "modulate:a", 0.0, UiKit.motion(0.5))
	tw.tween_callback(shadow.queue_free)


# 完美排雷：金光带加倍扫射 + 横幅占位（§2.2 最高档）
func play_perfect_sweep() -> void:
	for i in 2:
		var band := ColorRect.new()
		band.color = Color(COL_GOLD, 0.35)
		band.size = Vector2(size.x, 14.0 + 10.0 * i)
		band.position = Vector2(-size.x, size.y * 0.3 + 40.0 * i)
		band.mouse_filter = Control.MOUSE_FILTER_IGNORE
		add_child(band)
		var tw := band.create_tween()
		tw.tween_property(band, "position:x", size.x + 8.0, UiKit.motion(0.5 + 0.15 * i))
		tw.tween_callback(band.queue_free)
	_show_banner("完美排雷 ×2")


# 标中旗：旗化暴击弹道加重占位（自棋盘上缘飞向 B 区敌人卡方向——越界即收）
func play_flag_hit_projectile(heavy: bool) -> void:
	var shot := ColorRect.new()
	var w := 8.0 if heavy else 4.0
	shot.color = COL_FLAG
	shot.size = Vector2(w, w * 2.2)
	shot.position = Vector2(size.x * 0.5, size.y * 0.7)
	shot.mouse_filter = Control.MOUSE_FILTER_IGNORE
	add_child(shot)
	var tw := shot.create_tween()
	tw.tween_property(shot, "position", Vector2(size.x * 0.75, -30.0), UiKit.motion(0.35))
	tw.parallel().tween_property(shot, "modulate:a", 0.0, UiKit.motion(0.35))
	tw.tween_callback(shot.queue_free)


func _show_banner(text: String) -> void:
	_banner.text = text
	_banner.visible = true
	_banner.modulate.a = 0.0
	var tw := create_tween()
	tw.tween_property(_banner, "modulate:a", 1.0, UiKit.motion(0.2))
	tw.tween_interval(UiKit.motion(1.6))
	tw.tween_property(_banner, "modulate:a", 0.0, UiKit.motion(0.4))
	tw.tween_callback(func(): _banner.visible = false)