影炮：蓄一秒，暗影弹道贯穿全屏

 fx-shadowcannon

-- @file ShadowCannon.lua
-- 影炮 —— 蓄一秒射一道暗影弹道穿全屏

local ShadowCannon = {}

local CONST = {
    CHARGE_TIME   = 1.0,
    CANNON_CD     = 6.0,
    CANNON_DMG    = 55,

    COLOR_CANNON  = "#6a5ab8",
    COLOR_DEEP    = "#2a1a5e",
    COLOR_GHOST   = "#d8d0f8",

    ZORDER_CANNON = 135,
    AUTOINC_BASE  = 985000,
}

local _chargeT   = 0
local _charging  = false
local _cdLeft    = 0
local _scheduler = nil
local _autoInc   = 0

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

-- 蓄力入口
function ShadowCannon.Cast()
    if _cdLeft > 0 or _charging then return end
    _charging = true
    _chargeT = 0
    ShowTip("蓄了——一秒后出膛，线上全挨五十五")
end

-- 出膛结算
local function Cannon_Fire(myID)
    local mp = GetActorPos(myID)
    if not mp then return end
    for _, id in ipairs(SL:GetAllActorsInView()) do
        if id ~= myID then
            local tp = GetActorPos(id)
            if tp and math.abs(tp.y - mp.y) <= 40
                and tp.x > mp.x then
                SL:ActorHurt(id, CONST.CANNON_DMG)
                SL:TipAbove(id, "-" .. CONST.CANNON_DMG)
            end
        end
    end
    SL:PlayCannonBeam(mp.x, mp.y)
    SL:ScreenShake(3.4, 0.2)
end

-- 定时器：蓄力推进与出膛
if not _scheduler then
    _scheduler = SL:Schedule(function(dt)
        _cdLeft = math.max(0, _cdLeft - dt)
        if not _charging then return end
        _chargeT = _chargeT + dt
        if _chargeT >= CONST.CHARGE_TIME then
            _charging = false
            Cannon_Fire(SL:GetValue("USER_ID"))
        end
    end, 0.02)
end

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

return ShadowCannon