偷影：偷走它的影子，没了影子的怪刀都虚

 fx-shadowsteal

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-- @file        ShadowSteal.lua
-- @brief       偷影 —— 偷走它的影子，没了影子的怪刀都虚
--              客户端表现模块：配置表 / 影子构件 / 三态状态机 / 定时器
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local ShadowSteal = {}

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-- 配置与常量
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local CONST = {
    SHADOW_LIFE   = 6.0,        -- 偷影六秒
    SHADOW_CD     = 12.0,       -- 冷却十二秒
    TRAVEL_SPEED  = 3.0,        -- 影子爬行插值
    FOE_CUT       = 0.5,        -- 无影的它刀腿各半
    MY_AMP        = 1.2,        -- 你加两成

    -- 颜色
    COLOR_SHADOW  = "#7a8fa8",  -- 影青
    COLOR_DEEP    = "#3a4050",  -- 影灰
    COLOR_GHOST   = "#c8d0e0",  -- 影白

    ZORDER_GROUND = 118,
    ZORDER_SHADOW = 117,
    ZORDER_EFFECT = 135,

    AUTOINC_BASE  = 943000,
}

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-- 模块内部状态
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local _state     = "own"         -- own / travel / stolen
local _shadowX   = 0             -- 爬行态影子的横坐标
local _shadowT   = 0             -- 偷走态余时
local _cdLeft    = 0
local _scheduler = nil
local _autoInc   = 0

local m_cos = math.cos
local m_sin = math.sin

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-- 辅助函数
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local function GenID(prefix)
    _autoInc = _autoInc + 1
    return string.format("%s_%d", prefix or "SST", CONST.AUTOINC_BASE + _autoInc)
end

local function GetActorPos(actorID)
    if not actorID then return nil end
    local x = SL:GetValue("ACTOR_POSITION_X", actorID)
    local y = SL:GetValue("ACTOR_POSITION_Y", actorID)
    if not x or not y then return nil end
    return { x = x, y = y }
end

local function SafeRemove(node)
    if node and not GUI:Widget_IsNull(node) then
        GUI:removeFromParent(node)
    end
end

local function ShowTip(msg)
    if msg and msg ~= "" then SL:ShowSystemTips(msg) end
end

---影子构件：深色椭圆加虚线空壳两套
local function CreateShadowNode(x)
    local node = GUI:Layout_Create(GUI:Attach_SceneF(), GenID("Shd"), x, 6, 0, 0, false)
    GUI:setLocalZOrder(node, CONST.ZORDER_SHADOW)
    for i = 1, 18 do
        local a1 = (i - 1) / 18 * 6.28
        local a2 = i / 18 * 6.28
        GUI:DrawLine_Create(node, string.format("s_%d", i), 0, 0, 4,
            m_cos(a1) * 26, m_sin(a1) * 8, m_cos(a2) * 26, m_sin(a2) * 8,
            CONST.COLOR_DEEP, 210)
    end
    return node
end

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-- 偷影入口
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function ShadowSteal.Cast(targetX)
    if _cdLeft > 0 or _state ~= "own" then return end
    _cdLeft = CONST.SHADOW_CD
    _state = "travel"
    _shadowX = targetX
    ShowTip("影子拽出来了——看着它爬到你脚下")
end

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-- 属性改写：偷走态的两本账
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local function FoeFactor()
    if _state == "stolen" then return CONST.FOE_CUT end
    return 1.0
end

local function MyFactor()
    if _state == "stolen" then return CONST.MY_AMP end
    return 1.0
end

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-- 定时器：三态状态机
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if not _scheduler then
    _scheduler = SL:Schedule(function(dt)
        _cdLeft = math.max(0, _cdLeft - dt)
        local mp = GetActorPos(SL:GetValue("USER_ID"))
        local tp = GetActorPos(SL:GetValue("MARK_TARGET_ID"))
        if _state == "travel" then
            if not mp then return end
            _shadowX = _shadowX + (mp.x - _shadowX) * math.min(1, CONST.TRAVEL_SPEED * dt)
            SL:MoveNode(SL:GetShadowNode(), _shadowX, 6)
            if math.abs(_shadowX - mp.x) < 8 then
                _state = "stolen"
                _shadowT = CONST.SHADOW_LIFE
                SL:TipAbove(SL:GetValue("MARK_TARGET_ID"), "发虚！")
                ShowTip("影子到手——它刀软一半腿慢一半，你加两成")
            end
        elseif _state == "stolen" then
            _shadowT = _shadowT - dt
            SL:MoveNode(SL:GetShadowNode(), mp and mp.x or _shadowX, 6)
            if _shadowT <= 0 then
                _state = "own"
                ShowTip("影子爬回去了——它缓过劲了")
            end
        end
        if tp then
            SL:SetActorSpeedAmp(SL:GetValue("MARK_TARGET_ID"),
                _state == "stolen" and CONST.FOE_CUT or 1.0)
        end
        SL:SetNextAttackAmp(MyFactor())
    end, 0.02)
end

SL:RegisterLUAEvent(LUA_EVENT_SCENE_CLEAR, "SST_Clear", function()
    _state = "own"
    SL:SetNextAttackAmp(1.0)
end)

SL:ScheduleOnce(function()
    ShowTip("技能已加载: 偷影 (调试按钮触发)")
end, 1.0)

return ShadowSteal