function EnemyFilter takes nothing returns boolean
    if GetUnitState(GetFilterUnit(),UNIT_STATE_LIFE) <= 0 then
        return false
    endif
    if GetOwningPlayer(GetFilterUnit()) == Player(8) then
        return true
    endif
    if GetOwningPlayer(GetFilterUnit()) == Player(9) then
        return true
    endif
    if GetOwningPlayer(GetFilterUnit()) == Player(10) then
        return true
    endif
    if GetOwningPlayer(GetFilterUnit()) == Player(11) then
        return true
    endif
    return false
endfunction

function ChainLightning takes unit u returns nothing
    local unit array d //сюда нужно по-очереди запихнуть все цели для цепной молнии, начиная с 1 и заканчивая 6-ю (бьет по 6 врагам)
    local filterfunc ff = Filter(function EnemyFilter) //фильтр для юнитов, которые должны попасть в массив
    local real range = 600 //дистанция, на которой действует цепная молния (считается от позиции прошлой цели)
    set d[1] = u//первая цель известна
    endfunction

function EnemyFilter takes nothing returns boolean
    return GetUnitState(GetFilterUnit(), UNIT_STATE_LIFE) > 0
endfunction

function DistanceBetweenCord takes real AX, real AY, real BX, real BY returns real
    local real dx = BX - AX
    local real dy = BY - AY
    return SquareRoot(dx * dx + dy * dy)
endfunction

function ChainLightning_CreateLightning_Timer takes nothing returns nothing       
    local timer Timer = GetExpiredTimer()
    local unit Unit1 = I2U(GetStoredInteger (udg_cache, I2S(H2I(Timer)), "Unit1"))
    local unit Unit2 = I2U(GetStoredInteger (udg_cache, I2S(H2I(Timer)), "Unit2")) 
    local integer Time = GetStoredInteger (udg_cache, I2S(H2I(Timer)), "Time")   
    local real StartTime = I2R(GetStoredInteger (udg_cache, I2S(H2I(Timer)), "StartTime"))
    local lightning L = I2Li(GetStoredInteger (udg_cache, I2S(H2I(Timer)), "Lightning"))
    if Time > 0 then
        call MoveLightningEx  (L, true, GetUnitX(Unit1), GetUnitY(Unit1), GetUnitFlyHeight(Unit1)+30, GetUnitX(Unit2), GetUnitY(Unit2), GetUnitFlyHeight(Unit2)+30)
        call SetLightningColor(L, 1, 1, 1, I2R(Time)/StartTime)
        call StoreInteger (udg_cache, I2S(H2I(Timer)), "Time", Time-1)
    else        
        call DestroyLightning(L)
        call FlushStoredMission(udg_cache, I2S(H2I(Timer)))
        call DestroyTimer(Timer)
    endif
endfunction

function ChainLightning_CreateLightning takes unit Caster, unit Unit1, unit Unit2, string CodeName, real time returns nothing
    local timer Timer = CreateTimer()
    local lightning L = AddLightningEx(CodeName, true, GetUnitX(Unit1), GetUnitY(Unit1), GetUnitFlyHeight(Unit1)+30, GetUnitX(Unit2), GetUnitY(Unit2), GetUnitFlyHeight(Unit2)+30)
    call TimerStart(Timer, 0.02, true, function ChainLightning_CreateLightning_Timer)
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "Unit1"    , H2I(Unit1  ))
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "Unit2"    , H2I(Unit2  )) 
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "Lightning", H2I(L      )) 
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "Time"     , R2I(time*50)) 
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "StartTime", R2I(time*50))
    call DestroyEffect(AddSpecialEffectTarget("Abilities\\Weapons\\Bolt\\BoltImpact.mdl", Unit2, "origin"))  
    call UnitDamageTargetBJ(Caster, Unit2, 300, ATTACK_TYPE_NORMAL, DAMAGE_TYPE_LIGHTNING)
endfunction

function ChainLightning_Timer takes nothing returns nothing
    local timer Timer = GetExpiredTimer()
    local integer Index =   GetStoredInteger (udg_cache, I2S(H2I(Timer)), "Index")
    local real Len    =     GetStoredReal    (udg_cache, I2S(H2I(Timer)), "Len"  )
    local real Len2
    local unit NextUnit = null
    local unit LastUnit = I2U(GetStoredInteger (udg_cache, I2S(H2I(Timer)), "LastUnit"))
    local real X = GetUnitX(LastUnit) 
    local real Y = GetUnitY(LastUnit)
    local group gr = CreateGroup()
    local unit u
    local string CodeName = GetStoredString (udg_cache, I2S(H2I(Timer)), "CodeName")
    local filterfunc ff = Filter(function EnemyFilter)
    call GroupEnumUnitsInRange (gr, X, Y, Len, ff)
    call DestroyBoolExpr(ff)
    loop
        set u = FirstOfGroup(gr)
        exitwhen u == null
        if not GetStoredBoolean (udg_cache, "ChainLightning-"+I2S(H2I(u)), I2S(Index)) then
            set Len2 = DistanceBetweenCord(X, Y, GetUnitX(u), GetUnitY(u))
            if Len2<Len then
                set Len = Len2
                set NextUnit = u
            endif
        endif
        call GroupRemoveUnit(gr, u)
    endloop
    call DestroyGroup(gr)
    if NextUnit != null then
        call StoreBoolean(udg_cache, "ChainLightning-"+I2S(H2I(NextUnit)), I2S(Index), true)  
        call StoreInteger (udg_cache, I2S(H2I(Timer)), "LastUnit", H2I(NextUnit))                 
        call ChainLightning_CreateLightning(I2U(GetStoredInteger (udg_cache, I2S(H2I(Timer)), "Caster")), LastUnit, NextUnit, CodeName, GetStoredReal(udg_cache, I2S(H2I(Timer)), "TimeRemove"))
    else
        call FlushStoredMission(udg_cache, I2S(H2I(Timer)))
        call DestroyTimer(Timer)
    endif
endfunction

function ChainLightning takes unit Caster, unit Target, real Period, real TimeRemove, string CodeName, real Len returns nothing
    local timer Timer = CreateTimer()
    local integer Index = GetStoredInteger(udg_cache, "ChainLightning", "Index")+1
    call StoreBoolean(udg_cache, "ChainLightning-"+I2S(H2I(Caster)), I2S(Index), true)
    call StoreBoolean(udg_cache, "ChainLightning-"+I2S(H2I(Target)), I2S(Index), true)
    call ChainLightning_CreateLightning(Caster, Caster, Target, CodeName, TimeRemove)
    call TimerStart(Timer, Period, true, function ChainLightning_Timer)
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "Caster"  , H2I(Caster))
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "LastUnit", H2I(Target))
    call StoreReal    (udg_cache, I2S(H2I(Timer)), "Len"     , Len        ) 
    call StoreReal    (udg_cache, I2S(H2I(Timer)), "TimeRemove", TimeRemove)
    call StoreString  (udg_cache, I2S(H2I(Timer)), "CodeName", CodeName   )
    call StoreInteger (udg_cache, I2S(H2I(Timer)), "Index"   , Index      )   
    call StoreInteger(udg_cache, "ChainLightning", "Index"   , Index      )   
    set Timer = null
endfunction