local Players = game:GetService("Players")
local RunService = game:GetService("RunService")

local LocalPlayer = Players.LocalPlayer
local Camera = workspace.CurrentCamera

local MAX_DISTANCE = 500
local LOCK_ON = true
local TEAM_CHECK = true
local WALL_CHECK = true

local CurrentTarget = nil
local Highlight = nil

local function isEnemy(player)
	if player == LocalPlayer then
		return false
	end

	if TEAM_CHECK and player.Team == LocalPlayer.Team then
		return false
	end

	return true
end

local function isVisible(character)
	if not WALL_CHECK then
		return true
	end

	local head = character:FindFirstChild("Head")
	if not head then
		return false
	end

	local origin = Camera.CFrame.Position
	local direction = head.Position - origin

	local params = RaycastParams.new()
	params.FilterType = Enum.RaycastFilterType.Exclude
	params.FilterDescendantsInstances = {
		LocalPlayer.Character,
		character
	}

	local result = workspace:Raycast(origin, direction, params)

	return result == nil
end

local function getNearestEnemy()
	local nearest = nil
	local nearestDistance = MAX_DISTANCE

	local myCharacter = LocalPlayer.Character
	local myRoot = myCharacter and myCharacter:FindFirstChild("HumanoidRootPart")

	if not myRoot then
		return nil
	end

	for _, player in ipairs(Players:GetPlayers()) do
		if isEnemy(player) then
			local character = player.Character
			local humanoid = character and character:FindFirstChildOfClass("Humanoid")
			local head = character and character:FindFirstChild("Head")

			if humanoid and head and humanoid.Health > 0 then
				local distance = (head.Position - myRoot.Position).Magnitude

				if distance < nearestDistance and isVisible(character) then
					nearest = player
					nearestDistance = distance
				end
			end
		end
	end

	return nearest
end

local function removeHighlight()
	if Highlight then
		Highlight:Destroy()
		Highlight = nil
	end
end

local function highlightTarget(player)
	removeHighlight()

	if not player or not player.Character then
		return
	end

	Highlight = Instance.new("Highlight")
	Highlight.Name = "LockOnHighlight"
	Highlight.Adornee = player.Character
	Highlight.FillTransparency = 0.5
	Highlight.OutlineTransparency = 0
	Highlight.Parent = player.Character
end

local function setTarget(player)
	if CurrentTarget == player then
		return
	end

	CurrentTarget = player
	highlightTarget(player)
end

local function clearTarget()
	CurrentTarget = nil
	removeHighlight()
end

RunService.RenderStepped:Connect(function()
	if not LOCK_ON then
		clearTarget()
		return
	end

	if not CurrentTarget then
		setTarget(getNearestEnemy())
	end

	if CurrentTarget then
		local character = CurrentTarget.Character
		local humanoid = character and character:FindFirstChildOfClass("Humanoid")
		local head = character and character:FindFirstChild("Head")

		if not character
			or not humanoid
			or humanoid.Health <= 0
			or not head
			or not isEnemy(CurrentTarget)
			or not isVisible(character) then

			clearTarget()
			setTarget(getNearestEnemy())
		else
			-- Aim directly at the target's Head
			Camera.CFrame = CFrame.lookAt(
				Camera.CFrame.Position,
				head.Position
			)
		end
	end
end)