rbxIdleWeapon/src/ServerStorage/Modules/DamageLib.luau

--[[
	Evercyan @ March 2023
	DamageLib
	
	DamageLib houses code relating to damage for weapons, and any additional sources of damage
	you may add to your game. It is recommended to have all code for damage run through here for consistency.
	
	If you're looking to adjust crit multiplier, gamepass rewards (ex. x3 damage), etc, you can do this under DamageLib:DamageMob().
]]

--> Services
local CollectionService = game:GetService("CollectionService")
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local ServerStorage = game:GetService("ServerStorage")

--> Dependencies
local Mobs = require(ServerStorage.Modules.MobLib.MobList)

--> Variables
local DamageCd = {}
local Random = Random.new()

--------------------------------------------------------------------------------

local DamageLib = {}

function DamageLib:TagMobForDamage(Player: Player, Mob, Damage: number)
	if Mob.isDead then return end
	
	local PlayerTags = Mob.Instance:FindFirstChild("PlayerTags")
	if not PlayerTags then
		PlayerTags = Instance.new("Configuration")
		PlayerTags.Name = "PlayerTags"
		PlayerTags.Parent = Mob.Instance
	end
	
	local ExistingTag = PlayerTags:GetAttribute(Player.UserId)
	if ExistingTag then
		PlayerTags:SetAttribute(Player.UserId, ExistingTag + Damage)
	else
		PlayerTags:SetAttribute(Player.UserId, Damage)
	end
end

function DamageLib:DamageMob(Player: Player, Mob): number?
	if Mob.isDead then return end
	
	local pData = ReplicatedStorage.PlayerData:FindFirstChild(Player.UserId)
	local Level = pData and pData:FindFirstChild("Stats") and pData.Stats:FindFirstChild("Level")
	if not Level or (Level.Value < Mob.Config.Level[2]) then
		return
	end
	
	-- Make sure the equipped tool can be found, so we can safely grab the damage from it.
	-- Never pass damage as a number through a remote, as the client can manipulate this data.
	local Character = Player.Character
	local Tool = Character and Character:FindFirstChildOfClass("Tool")
	local ItemConfig = Tool and Tool:FindFirstChild("ItemConfig") and require(Tool.ItemConfig)
	if not ItemConfig or not ItemConfig.Damage then return end
	
	-- Damage Cooldown
	if DamageCd[Player.UserId] then return end
	DamageCd[Player.UserId] = true
	task.delay(ItemConfig.Cooldown - 0.03, function() -- We subtract just a tad so inconsistencies with timing on the client (ie. time to raycast) is less likely to stop a hit from going through
		DamageCd[Player.UserId] = nil
	end)
	
	-- Calculate damage
	local Damage = typeof(ItemConfig.Damage) == "table" and Random:NextInteger(unpack(ItemConfig.Damage)) or ItemConfig.Damage
	local isCrit = Random:NextInteger(1, 10) == 1
	
	if isCrit then
		Damage *= 2
	end
	
	self:TagMobForDamage(Player, Mob, Damage)
	Mob.Enemy.Health = math.clamp(Mob.Enemy.Health - Damage, 0, Mob.Enemy.MaxHealth)
	ReplicatedStorage.Remotes.PlayerDamagedMob:FireClient(Player, Mob.Instance, Damage)
	
	return Damage
end

ReplicatedStorage.Remotes.DamageMob.OnServerInvoke = function(Player, MobInstance: Model)
	if MobInstance and typeof(MobInstance) == "Instance" and CollectionService:HasTag(MobInstance, "Mob") then
		local Mob = Mobs[MobInstance]
		
		if Mob then
			-- Follow
			local Enemy = Mob.Instance:FindFirstChild("Enemy")
			if Enemy and (not Enemy.WalkToPart or not Enemy.WalkToPart:IsDescendantOf(Player.Character)) then
				local HumanoidRootPart = Mob.Instance:FindFirstChild("HumanoidRootPart")
				if HumanoidRootPart then
					HumanoidRootPart.Anchored = false
					HumanoidRootPart:SetNetworkOwner(Player)
					Enemy:MoveTo(Player.Character:GetPivot().Position)
				end
			end
			return DamageLib:DamageMob(Player, Mob)
		end
	end
end

return DamageLib