Keep Items after leaving -- Roblox

local folders_to_save = {
    ['Backpack'] = game.ReplicatedStorage.Items
}

local reload_items_on_reset = true

local DataStoreService = game:GetService("DataStoreService")
local ItemStore = DataStoreService:GetDataStore("ItemStore")

local PlayerData = {}

local function LoadItemsFromData(player: Player, data, onReset: boolean)
    local folders = {}

    for storeFolderName, itemsFolder in pairs(folders_to_save) do
        local folder = player:FindFirstChild(storeFolderName)
        if not folder then
            folder = Instance.new("Folder")
            folder.Name = storeFolderName
            folder.Parent = player
        end
        folders[storeFolderName] = folder
    end

    local function AddItem(item: Instance, folder: Folder, index: number)

        if not data[folder.Name] then
            data[folder.Name] = {}
        end

        if not index then
            index = #data[folder.Name] + 1
            table.insert(data[folder.Name], index, item.Name)
        end


        item.AncestryChanged:Connect(function(_, newParent)
            if newParent ~= folder and folder.Parent ~= nil then
                data[folder.Name][index] = nil
            end
        end)
    end

    for storeFolderName, savedItems in pairs(data) do

        if onReset == true and storeFolderName ~= 'Backpack' then
            continue
        end


        local itemsFolder: Folder = folders_to_save[storeFolderName]

        if itemsFolder then

            local folder = folders[storeFolderName]

            for index, itemName in pairs(savedItems) do
                local item = itemsFolder:FindFirstChild(itemName)
                if item then
                    local playerItem = item:Clone()
                    playerItem.Parent = folder

                    AddItem(playerItem, folder, index)
                else
                    warn(player, 'has unknown item that is said to be in folder', storeFolderName, ":", itemName)
                end
            end

        else
            warn(player, 'has unknown directory saved in data:', storeFolderName)
        end
    end


    for storeFolderName, folder in pairs(folders) do
        folders[storeFolderName] = nil

        if onReset == true and storeFolderName ~= 'Backpack' then
            continue
        end

        folder.ChildAdded:Connect(function(item)
            AddItem(item, folder)
        end)
    end
end

local function Load(player: Player)

    if PlayerData[player] then
        return warn(player, 'data is already loaded')
    end

    local dataKey = 'key_' .. player.UserId

    local loadedData = nil
    local success, result = pcall(function()
        loadedData = ItemStore:GetAsync(dataKey)
    end)

    if not success then
        error(success)
    end

    if loadedData == nil then
        loadedData = {} -- we give it empty data
    end

    warn(player, 'items have been loaded')

    return loadedData
end

local function Save(player: Player)
    local dataKey = 'key_' .. player.UserId

    local data = PlayerData[player]

    local success, result = pcall(function()
        ItemStore:SetAsync(dataKey, data, {player.UserId})
    end)

    if not success then
        error(result)
    end

    warn('Successfully saved', player, 'items to Datastore')
end

game.Players.PlayerAdded:Connect(function(player: Player)
    local data = Load(player)
    PlayerData[player] = data

    local character = player.Character or player.CharacterAdded:Wait()
    LoadItemsFromData(player, data)

    if reload_items_on_reset == true then
        player.CharacterAdded:Connect(function(character: Model)
            LoadItemsFromData(player, data, true)
        end)
    end
end)

game.Players.PlayerRemoving:Connect(function(player: Player)
    Save(player)

    if PlayerData[player] then
        table.clear(PlayerData[player])
    end

    PlayerData[player] = nil
end)

game:BindToClose(function()
    for _, player in pairs(game.Players:GetPlayers()) do
        Save(player)
    end
end)