--!strict

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

local player = Players.LocalPlayer

-- =========================
-- CONFIG
-- =========================
local CONFIG = {
	TargetSpeed = 250,              -- ความเร็วหลักแกน Z
	RoadName = "AutoFarmRoad",
	RoadSize = Vector3.new(200, 10, 900000),
	RoadPosition = Vector3.new(0, 10000, 0),

	SpawnPosition = Vector3.new(0, 10015, 0),
	SpawnYaw = 0,                   -- องศาที่หันตอนวางรถกลับ

	MinYBeforeReset = 9500,
	MaxZBeforeReset = 400000,

	CenterX = 0,                    -- กลางถนน
	CenteringGain = 4.5,            -- แรงดึงกลับแกน X
	MaxSideVelocity = 120,          -- จำกัดความเร็วด้านข้าง ไม่ให้ดีดแรงเกิน

	TeleportCooldown = 0.25,

	OrientationResponsiveness = 50, -- ค่ายิ่งมากยิ่งหันไว
	OrientationMaxTorque = 1e9,
}

-- =========================
-- STATE
-- =========================
local currentVehicle: Model? = nil
local currentMainPart: BasePart? = nil
local isResetting = false
local heartbeatConnection: RBXScriptConnection? = nil

-- =========================
-- ROAD SETUP
-- =========================
local function ensureRoad(): Part
	local road = workspace:FindFirstChild(CONFIG.RoadName)

	if road and road:IsA("Part") then
		road.Size = CONFIG.RoadSize
		road.Position = CONFIG.RoadPosition
		return road
	end

	if road and not road:IsA("Part") then
		road:Destroy()
	end

	local newRoad = Instance.new("Part")
	newRoad.Name = CONFIG.RoadName
	newRoad.Size = CONFIG.RoadSize
	newRoad.Position = CONFIG.RoadPosition
	newRoad.Anchored = true
	newRoad.CanCollide = true
	newRoad.CanTouch = false
	newRoad.CanQuery = false
	newRoad.Transparency = 0.5
	newRoad.Material = Enum.Material.SmoothPlastic
	newRoad.CastShadow = false
	newRoad.Locked = true
	newRoad.Parent = workspace

	return newRoad
end

ensureRoad()

-- =========================
-- UTILS
-- =========================
local function getCharacter(): Model?
	return player.Character
end

local function getHumanoid(character: Model?): Humanoid?
	if not character then
		return nil
	end
	return character:FindFirstChildOfClass("Humanoid")
end

local function getSeatedVehicle(): (Model?, BasePart?)
	local character = getCharacter()
	local humanoid = getHumanoid(character)

	if not character or not humanoid then
		return nil, nil
	end

	local seat = humanoid.SeatPart
	if not seat or not seat:IsA("BasePart") then
		return nil, nil
	end

	local vehicle = seat:FindFirstAncestorOfClass("Model")
	if not vehicle then
		return nil, nil
	end

	local mainPart = vehicle.PrimaryPart or seat
	if not mainPart or not mainPart:IsA("BasePart") then
		return nil, nil
	end

	return vehicle, mainPart
end

local function clearControllerObjects(part: BasePart?)
	if not part then
		return
	end

	local oldAttachment = part:FindFirstChild("AF_Attachment")
	if oldAttachment then
		oldAttachment:Destroy()
	end

	local oldAlign = part:FindFirstChild("AF_AlignOrientation")
	if oldAlign then
		oldAlign:Destroy()
	end
end

local function setupOrientationController(part: BasePart)
	clearControllerObjects(part)

	local attachment = Instance.new("Attachment")
	attachment.Name = "AF_Attachment"
	attachment.Parent = part

	local align = Instance.new("AlignOrientation")
	align.Name = "AF_AlignOrientation"
	align.Mode = Enum.OrientationAlignmentMode.OneAttachment
	align.Attachment0 = attachment
	align.RigidityEnabled = false
	align.ReactionTorqueEnabled = false
	align.Responsiveness = CONFIG.OrientationResponsiveness
	align.MaxTorque = CONFIG.OrientationMaxTorque
	align.CFrame = CFrame.lookAt(Vector3.zero, Vector3.new(0, 0, 1), Vector3.new(0, 1, 0))
	align.Parent = part
end

local function bindVehicle(vehicle: Model, mainPart: BasePart)
	if currentMainPart == mainPart and currentVehicle == vehicle then
		return
	end

	if currentMainPart then
		clearControllerObjects(currentMainPart)
	end

	currentVehicle = vehicle
	currentMainPart = mainPart
	setupOrientationController(mainPart)
end

local function unbindVehicle()
	if currentMainPart then
		clearControllerObjects(currentMainPart)
	end

	currentVehicle = nil
	currentMainPart = nil
end

local function resetVehicle(vehicle: Model?, mainPart: BasePart?)
	if isResetting or not mainPart then
		return
	end

	isResetting = true

	mainPart.AssemblyLinearVelocity = Vector3.zero
	mainPart.AssemblyAngularVelocity = Vector3.zero

	local spawnCF = CFrame.new(CONFIG.SpawnPosition) * CFrame.Angles(0, math.rad(CONFIG.SpawnYaw), 0)

	if vehicle then
		vehicle:PivotTo(spawnCF)
	else
		mainPart.CFrame = spawnCF
	end

	task.delay(CONFIG.TeleportCooldown, function()
		isResetting = false
	end)
end

-- =========================
-- MAIN LOOP
-- =========================
local function stepVehicle()
	if isResetting then
		return
	end

	local vehicle, mainPart = getSeatedVehicle()
	if not vehicle or not mainPart then
		unbindVehicle()
		return
	end

	bindVehicle(vehicle, mainPart)

	local pos = mainPart.Position

	-- รีเซ็ตกลับต้นทางถ้าหลุดจากพื้นที่ที่กำหนด
	if pos.Y < CONFIG.MinYBeforeReset or pos.Z > CONFIG.MaxZBeforeReset then
		resetVehicle(vehicle, mainPart)
		return
	end

	-- ล็อกอัตราหมุนไม่ให้รถเหวี่ยง/ล้มง่าย
	mainPart.AssemblyAngularVelocity = Vector3.zero

	-- ดึงกลับสู่แกนกลางถนน
	local lateralError = CONFIG.CenterX - pos.X
	local sideVelocity = math.clamp(
		lateralError * CONFIG.CenteringGain,
		-CONFIG.MaxSideVelocity,
		CONFIG.MaxSideVelocity
	)

	-- คง Y velocity เดิมไว้ เพื่อไม่ฝืนแรงโน้มถ่วงจนผิดธรรมชาติ
	local currentYVelocity = mainPart.AssemblyLinearVelocity.Y

	mainPart.AssemblyLinearVelocity = Vector3.new(
		sideVelocity,
		currentYVelocity,
		CONFIG.TargetSpeed
	)
end

-- กันรันซ้ำแล้วมีหลาย connection
if _G.AutoDriveConnection then
	_G.AutoDriveConnection:Disconnect()
	_G.AutoDriveConnection = nil
end

heartbeatConnection = RunService.Heartbeat:Connect(stepVehicle)
_G.AutoDriveConnection = heartbeatConnection

-- cleanup ตอนตัวละครเปลี่ยน
player.CharacterRemoving:Connect(function()
	unbindVehicle()
end)