斩残血纹：它血越少，你刀越重

 fx-cutlow

-- @file CutLow.lua
-- 斩残纹 —— 它血越少，你刀越重

local CutLow = {}

local CONST = {
    CREST_LIFE    = 12.0,
    CREST_CD      = 5.0,
    BASE_HIT      = 10,
    AMP_MAX       = 20,

    COLOR_CUT     = "#c04848",
    COLOR_DEEP    = "#481414",
    COLOR_GHOST   = "#f0b8b8",

    ZORDER_CUT    = 133,
    ZORDER_FX     = 135,
    AUTOINC_BASE  = 1089000,
}

local _crestT    = 0
local _cdLeft    = 0
local _crestFx   = nil
local _scheduler = nil
local _autoInc   = 0

local function GenID(prefix)
    _autoInc = _autoInc + 1
    return string.format("%s_%d", prefix or "CTL",
        CONST.AUTOINC_BASE + _autoInc)
end

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

-- 残血侦测：按已损失比例取数，别再取反
local function MissRatio(tid)
    local hp  = SL:GetValue("ACTOR_HP", tid) or 0
    local hpM = SL:GetValue("ACTOR_HP_MAX", tid) or 1
    return 1 - hp / hpM
end

-- 加成曲线：已损失比例乘上限，线性走满
function CutLow.Bonus(tid)
    if _crestT <= 0 then return 0 end
    return math.floor(MissRatio(tid) * CONST.AMP_MAX)
end

-- 重刀结算：每一刀出手前先读它的血
SL:RegisterLUAEvent(LUA_EVENT_MELEE_DAMAGE, "CTL_Amp", function(tid)
    return CutLow.Bonus(tid)
end)

function CutLow.Cast()
    if _cdLeft > 0 or _crestT > 0 then return end
    local tid = SL:GetValue("MARK_TARGET_ID")
    if not tid then return end
    _cdLeft = CONST.CREST_CD
    _crestT = CONST.CREST_LIFE
    SafeRemove(_crestFx)
    _crestFx = GUI:Layout_Create(GUI:Attach_SceneF(),
        GenID("Crest"), 0, 0, 0, 0, false)
    GUI:setLocalZOrder(_crestFx, CONST.ZORDER_CUT)
    SL:PlayCrestUpFx(tid)
    SL:TipAbove(tid, "斩残！")
    ShowTip("斩残纹成了——它血越少，你刀越重")
end

-- 定时器：纹成倒计时与纹环跟脚
if not _scheduler then
    _scheduler = SL:Schedule(function(dt)
        _cdLeft = math.max(0, _cdLeft - dt)
        if _crestT > 0 then
            _crestT = _crestT - dt
            local tid = SL:GetValue("MARK_TARGET_ID")
            local tp = tid and GetActorPos(tid)
            if _crestFx and tp then
                GUI:setPosition(_crestFx, tp.x, tp.y - 96)
            end
            if _crestT <= 0 then
                SafeRemove(_crestFx)
                ShowTip("纹光散了——刀回十点")
            end
        end
    end, 0.02)
end

SL:ScheduleOnce(function()
    SL:BindDebugButton("纹成", function()
        CutLow.Cast()
    end)
    ShowTip("技能已加载: 斩残纹 (调试按钮触发)")
end, 1.0)

function CutLow.Unload()
    if _scheduler then SL:Unschedule(_scheduler) end
    SL:UnregisterLUAEvent(LUA_EVENT_MELEE_DAMAGE, "CTL_Amp")
    SafeRemove(_crestFx)
    _crestT = 0
end

return CutLow