-- StateManager.lua
local Knit = require(game:GetService("ReplicatedStorage").Packages.Knit)
local StateManager = Knit.CreateService {
    Name = "StateManager",
}

local Players = game:GetService("Players")

local StateClass = require(script.StateClass)

local LastChange = nil
local AlreadyCounting = false

local StateMachines = {
    HumanoidStateMachine = {},
    CombatStateMachine = {}
}

local IDLE_REVERT_TIME = 5
local ITERATION_INTERVAL = 1

local function ConfigureStates(Character)
    local Humanoid = Character:WaitForChild("Humanoid")
    local HumanoidStateMachine = StateMachines.HumanoidStateMachine

    Humanoid.StateChanged:Connect(function(_, NewState)
        if NewState ~= Enum.HumanoidStateType.Running then
            HumanoidStateMachine:ChangeState(NewState.Name)
        end
        LastChange = os.clock()

        if AlreadyCounting then return end
        AlreadyCounting = true

        while true do
            task.wait(ITERATION_INTERVAL)
            local DeltaTime = os.clock() - LastChange
            if DeltaTime >= IDLE_REVERT_TIME then
                break
            end
        end

        HumanoidStateMachine:ChangeState("Idle")
        AlreadyCounting = false
    end)

    HumanoidStateMachine:ChangeState("Idle")
end

function StateManager.KnitInit()
    for StateMachine,_ in StateMachines do
        StateMachines[StateMachine] = StateClass.new(StateMachine)
    end

    Players.PlayerAdded:Connect(function(Player)
        if Player.Character then ConfigureStates(Player.Character) end
        Player.CharacterAdded:Connect(ConfigureStates)
    end)
end

return StateManager

StateClass.lua
local StateClass = {}
StateClass.__index = StateClass


function StateClass.new(StateMachine)
    local self = setmetatable({}, StateClass)
    self.Name = StateMachine.."StateMachine"
    self.States = {}
    for _,State in ipairs(script[StateMachine]:GetChildren()) do
        self.States[State.Name] = require(State)
    end

    self.State = self.States["None"]
    return self
end

function StateClass:ChangeState(State)
    local ValidState = false

    for StateName, Other in self.States do
        if StateName == State then
            ValidState = true
            break
        end
    end
    if not ValidState then
        error("Attempted to change state to invalid state enum: "..tostring(State))
    end

    local OldState = self.State
    local NewState = self.States[State]

    if OldState.Exit then OldState.Exit() end
    if NewState.Enter then NewState.Enter() end

    self.State = NewState
    print("State Change:",self.State.Name)
end

function StateClass:FetchState(State)
    return self.State
end


return StateClass