local ABILITY_ID = AbilityId('SRaL')
local RANGE = 200
local DELAY = 1
local COLOR = {'Blue','Nature','Orange','Red','Void'}

---@author https://xgm.guru/p/wc3/random-lightning
do
	local InitGlobalOrigin = InitGlobals
	function InitGlobals()
		InitGlobalOrigin()
		
		-- Настройки
		local ABILITY_ID      = FourCC('SRaL')
		local RANGE           = 200
		local DELAY           = 1
		local COLOR           = { 'Blue', 'Nature', 'Orange', 'Red', 'Void' }
		local ICON_PATH       = 'ReplaceableTextures/CommandButtons/BTNSpellRandomLightning'
		
		-- Заклинание
		local GROUP_ENUM_ONCE = CreateGroup()
		local COLOR_CURRENT   = COLOR[math.random(1, #COLOR)]
		BlzSetAbilityIcon(ABILITY_ID, ICON_PATH .. COLOR_CURRENT .. '.blp')
		
		local trigger = CreateTrigger()
		for i = 0, bj_MAX_PLAYER_SLOTS - 1 do
			TriggerRegisterPlayerUnitEvent(trigger, Player(i), EVENT_PLAYER_UNIT_SPELL_EFFECT)
		end
		TriggerAddAction(trigger, function()
			if GetSpellAbilityId() ~= ABILITY_ID then return end
			
			local caster = GetTriggerUnit()
			local damage = BlzGetUnitBaseDamage(caster, 1) * GetUnitAbilityLevel(caster, ABILITY_ID)
			local x, y   = GetSpellTargetX(), GetSpellTargetY()
			local effect = AddSpecialEffect('Abilities/Spells/Human/MassTeleport/MassTeleportCaster.mdl', x, y)
			
			TimerStart(CreateTimer(), DELAY, false, function()
				DestroyEffect(effect)
				DestroyEffect(AddSpecialEffect('Effect/Spell/RandomLightning' .. COLOR_CURRENT .. '.mdx', x, y))
				
				GroupEnumUnitsInRange(GROUP_ENUM_ONCE, x, y, RANGE)
				while true do
					local target = FirstOfGroup(GROUP_ENUM_ONCE)
					if target == nil then break end
					
					if UnitAlive(target) and
							IsPlayerEnemy(GetOwningPlayer(caster), GetOwningPlayer(target)) and
							not IsUnitType(target, UNIT_TYPE_MAGIC_IMMUNE) and
							not IsUnitType(target, UNIT_TYPE_FLYING)
					then
						UnitDamageTarget(caster, target, damage, false, true, ATTACK_TYPE_MAGIC, DAMAGE_TYPE_NORMAL, WEAPON_TYPE_WHOKNOWS)
					end
					
					GroupRemoveUnit(GROUP_ENUM_ONCE, target)
				end
				
				COLOR_CURRENT = COLOR[math.random(1, #COLOR)]
				BlzSetAbilityIcon(ABILITY_ID, ICON_PATH .. COLOR_CURRENT .. '.blp')
				DestroyTimer(GetExpiredTimer())
			end)
		end)
	end
end