-- session state module
local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")

local Module = {}
Module.__index = Module

function Module.new(owner)
    local self = setmetatable({}, Module)
    self.owner = owner
    self.active = true
    self.data = {}
    return self
end

function Module:Update(dt)
    if not self.active then
        return
    end
    for key, value in pairs(self.data) do
        value.timer += dt
    end
end

function Module:Destroy()
    self.active = false
    table.clear(self.data)
end

Players.PlayerAdded:Connect(function(player)
    local session = Module.new(player)
    print(player.Name .. " joined")
end)

return Module

-- shop purchase handler
local DataStoreService = game:GetService("DataStoreService")
local ShopStore = DataStoreService:GetDataStore("ShopData")

local function canAfford(player, cost)
    local stats = player:FindFirstChild("leaderstats")
    if not stats then
        return false
    end
    return stats.Coins.Value >= cost
end

local function purchase(player, itemId, cost)
    if not canAfford(player, cost) then
        return false, "insufficient funds"
    end
    player.leaderstats.Coins.Value -= cost
    ShopStore:UpdateAsync(player.UserId, function(old)
        old = old or {}
        table.insert(old, itemId)
        return old
    end)
    return true
end

return {
    canAfford = canAfford,
    purchase = purchase,
}