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

local PASS_ID = 1234567890
local granted = {} -- idempotency guard: granted[player][passID]

local function grantPassBenefits(player: Player, passID: number)
    if not player or not player:IsDescendantOf(Players) then
        return
    end
    local playerGranted = granted[player]
    if not playerGranted then
        playerGranted = {}
        granted[player] = playerGranted
    end
    if playerGranted[passID] then
        return
    end
    playerGranted[passID] = true

    -- Apply the actual privilege (attributes, table entry, DataStore flag, Remote to client for visuals, etc.)
    -- This is the source of truth.
end

MarketplaceService.PromptGamePassPurchaseFinished:Connect(function(player: Player, purchasedPassID: number, wasPurchased: boolean)
    -- This event also fires on the client; never grant benefits from the client copy.
    if not player or typeof(purchasedPassID) ~= "number" then
        return
    end
    if wasPurchased and purchasedPassID == PASS_ID then
        local ok, err = pcall(function()
            grantPassBenefits(player, PASS_ID)
        end)
        if not ok then
            warn("Failed to grant pass benefits:", err)
        end
    end
end)

Players.PlayerAdded:Connect(function(player: Player)
    local success, owns = pcall(function()
        return MarketplaceService:UserOwnsGamePassAsync(player.UserId, PASS_ID)
    end)
    if success and owns then
        local ok, err = pcall(function()
            grantPassBenefits(player, PASS_ID)
        end)
        if not ok then
            warn("Failed to apply owned pass benefits:", err)
        end
    elseif not success then
        warn("UserOwnsGamePassAsync failed for", player.Name)
    end
end)

Players.PlayerRemoving:Connect(function(player: Player)
    granted[player] = nil
end)