分裂箭：一支裂三支，扇面三路齐发

 fx-splitarrow

--------------------------------------------------------------------------------
-- @file        SplitArrow.lua
-- @brief       分裂箭 —— 一支裂三支，扇面三路齐发
--              客户端表现模块：配置表 / 箭矢构件 / 分叉状态机 / 定时器
--------------------------------------------------------------------------------

local SplitArrow = {}

--------------------------------------------------------------------------------
-- 配置与常量
--------------------------------------------------------------------------------
local CONST = {
    SPLIT_CD      = 3.5,        -- 分裂箭冷却
    ARROW_SPEED   = 320,        -- 箭速三百二
    SUB_DMG       = 12,         -- 子箭十二
    FAN_SPREAD    = 90,         -- 两翼纵速差九十
    AUTO_DMG      = 10,         -- 平射十

    -- 颜色
    COLOR_ARROW   = "#d8c078",  -- 分裂金
    COLOR_DEEP    = "#6b5a2b",  -- 深金
    COLOR_GHOST   = "#f5eed8",  -- 箭白

    ZORDER_GROUND = 118,
    ZORDER_ARROW  = 133,
    ZORDER_EFFECT = 135,

    AUTOINC_BASE  = 965000,
}

--------------------------------------------------------------------------------
-- 模块内部状态
--------------------------------------------------------------------------------
local _arrows     = {}             -- 箭表
local _cdLeft     = 0
local _autoT      = 0
local _scheduler  = nil
local _autoInc    = 0

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

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

---箭矢构件：主箭金杆、子箭白杆
local function CreateArrowNode(isMain)
    local node = GUI:Layout_Create(GUI:Attach_SceneF(), GenID(isMain and "Main" or "Sub"),
        0, 0, 0, 0, false)
    GUI:setLocalZOrder(node, CONST.ZORDER_ARROW)
    local col = isMain and CONST.COLOR_ARROW or CONST.COLOR_GHOST
    GUI:DrawLine_Create(node, "shaft", 0, 0, 2, -10, 0, 10, 0, col, 240)
    GUI:DrawLine_Create(node, "head", 0, 0, 3, 10, 0, 5, -3, col, 240)
    GUI:DrawLine_Create(node, "head2", 0, 0, 3, 10, 0, 5, 3, col, 240)
    return node
end

--------------------------------------------------------------------------------
-- 分裂箭入口
--------------------------------------------------------------------------------
function SplitArrow.Cast()
    if _cdLeft > 0 then return end
    _cdLeft = CONST.SPLIT_CD
    local mp = GetActorPos(SL:GetValue("USER_ID"))
    local tp = GetActorPos(SL:GetValue("MARK_TARGET_ID"))
    if not mp or not tp then return end
    local midX = (mp.x + tp.x) / 2
    table.insert(_arrows, { x = mp.x + 16, y = mp.y - 58,
        vx = CONST.ARROW_SPEED, vy = 0, main = true, mid = midX,
        node = CreateArrowNode(true) })
    ShowTip("主箭出去了——半途裂三支")
end

--------------------------------------------------------------------------------
-- 定时器：主箭推进、分叉与子箭结算
--------------------------------------------------------------------------------
if not _scheduler then
    _scheduler = SL:Schedule(function(dt)
        _cdLeft = math.max(0, _cdLeft - dt)
        for i = #_arrows, 1, -1 do
            local a = _arrows[i]
            a.x = a.x + a.vx * dt
            a.y = a.y + a.vy * dt
            if a.main and a.x >= a.mid then
                SafeRemove(a.node)
                table.remove(_arrows, i)
                for s = -1, 1 do
                    table.insert(_arrows, { x = a.mid, y = a.y,
                        vx = CONST.ARROW_SPEED, vy = s * CONST.FAN_SPREAD,
                        main = false, node = CreateArrowNode(false) })
                end
                SL:TipAboveAt(a.mid, "分裂！")
            elseif not a.main then
                local tid = SL:GetValue("MARK_TARGET_ID")
                local tp = tid and GetActorPos(tid)
                if tp and math.abs(a.x - tp.x) < 18 and math.abs(a.y - (tp.y - 50)) < 50 then
                    SL:ActorHurt(tid, CONST.SUB_DMG)
                    SL:TipAbove(tid, "-" .. CONST.SUB_DMG)
                    SafeRemove(a.node)
                    table.remove(_arrows, i)
                end
            end
            if a.x > 700 then
                SafeRemove(a.node)
                table.remove(_arrows, i)
            end
        end
    end, 0.02)
end

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

return SplitArrow