--!strict
-- PORTFOLIO SAMPLE / ROBLOX STUDIO VALIDATION REQUIRED
-- Put this Script in ServerScriptService.
-- Isolated example: Daily Rewards + Promo Codes share ONE demo currency store.
-- Integrate with your game's existing economy before using in production.

local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local DataStoreService = game:GetService("DataStoreService")

local STORE = DataStoreService:GetDataStore("NeoPortfolioRewardDemo_v1")
local REMOTE_NAME = "NeoPortfolioRewardsAction"
local DAILY_REWARD = 150
local DAILY_COOLDOWN = 24 * 60 * 60
local PROMO_CODES: {[string]: number} = {
	WELCOME100 = 100,
	TEST50 = 50,
}

type Profile = {
	coins: number,
	lastDaily: number,
	redeemed: {[string]: boolean},
}

local profiles: {[number]: Profile} = {}
local loaded: {[number]: boolean} = {}
local busy: {[number]: boolean} = {}

local remote = ReplicatedStorage:FindFirstChild(REMOTE_NAME)
if not remote then
	remote = Instance.new("RemoteFunction")
	remote.Name = REMOTE_NAME
	remote.Parent = ReplicatedStorage
end
assert(remote:IsA("RemoteFunction"), "Reward remote must be a RemoteFunction")

local function sanitizedProfile(value: any): Profile
	local result: Profile = {coins = 0, lastDaily = 0, redeemed = {}}
	if type(value) ~= "table" then
		return result
	end
	if type(value.coins) == "number" and value.coins >= 0 and value.coins < 1e12 then
		result.coins = math.floor(value.coins)
	end
	if type(value.lastDaily) == "number" and value.lastDaily >= 0 then
		result.lastDaily = math.floor(value.lastDaily)
	end
	if type(value.redeemed) == "table" then
		for code, redeemed in pairs(value.redeemed) do
			if type(code) == "string" and redeemed == true and PROMO_CODES[code] then
				result.redeemed[code] = true
			end
		end
	end
	return result
end

local function getCoinsValue(player: Player): IntValue
	local stats = player:FindFirstChild("leaderstats")
	if not stats then
		stats = Instance.new("Folder")
		stats.Name = "leaderstats"
		stats.Parent = player
	end

	local existing = stats:FindFirstChild("Coins")
	if existing and existing:IsA("IntValue") then
		return existing
	end
	local coins = Instance.new("IntValue")
	coins.Name = "Coins"
	coins.Value = 0
	coins.Parent = stats
	return coins
end

local function publicState(profile: Profile): {[string]: any}
	local secondsLeft = math.max(0, DAILY_COOLDOWN - (os.time() - profile.lastDaily))
	return {
		coins = profile.coins,
		secondsLeft = secondsLeft,
		canClaim = secondsLeft == 0,
		reward = DAILY_REWARD,
	}
end

local function response(ok: boolean, message: string, profile: Profile?): {[string]: any}
	return {
		ok = ok,
		message = message,
		state = if profile then publicState(profile) else nil,
	}
end

local function loadPlayer(player: Player)
	local id = player.UserId
	getCoinsValue(player)
	local success, stored = pcall(function()
		return STORE:GetAsync("user_" .. tostring(id))
	end)
	if player.Parent ~= Players then
		return
	end
	if not success then
		warn("[RewardDemo] DataStore load failed for " .. id .. ": " .. tostring(stored))
		-- Fail closed: do not award coins if the saved state could not be read.
		loaded[id] = false
		return
	end
	local profile = sanitizedProfile(stored)
	profiles[id] = profile
	getCoinsValue(player).Value = profile.coins
	loaded[id] = true
end

Players.PlayerAdded:Connect(loadPlayer)
Players.PlayerRemoving:Connect(function(player)
	-- Claims are persisted immediately with UpdateAsync; there is no leave-time write.
	profiles[player.UserId] = nil
	loaded[player.UserId] = nil
	busy[player.UserId] = nil
end)
for _, player in Players:GetPlayers() do
	task.spawn(loadPlayer, player)
end

remote.OnServerInvoke = function(player: Player, action: any, detail: any)
	local id = player.UserId
	if not loaded[id] or not profiles[id] then
		return response(false, "Data is still loading or unavailable. Try again shortly.", nil)
	end
	local current = profiles[id]
	if action == "status" then
		return response(true, "Ready", current)
	end
	if action ~= "daily" and action ~= "promo" then
		return response(false, "Unknown action", current)
	end
	if busy[id] then
		return response(false, "Please wait for the current action", current)
	end

	local now = os.time()
	local promoCode: string? = nil
	if action == "promo" then
		if type(detail) ~= "string" or #detail > 40 then
			return response(false, "Invalid code", current)
		end
		promoCode = string.upper(string.gsub(detail, "%s+", ""))
		if PROMO_CODES[promoCode] == nil then
			return response(false, "Code not found", current)
		end
	end
	if action == "daily" and now - current.lastDaily < DAILY_COOLDOWN then
		return response(false, "Your daily reward is on cooldown", current)
	end
	if promoCode and current.redeemed[promoCode] then
		return response(false, "You already used that code", current)
	end

	busy[id] = true
	local success, stored = pcall(function()
		return STORE:UpdateAsync("user_" .. tostring(id), function(oldData: any)
			local nextProfile = sanitizedProfile(oldData)
			if action == "daily" then
				if now - nextProfile.lastDaily < DAILY_COOLDOWN then
					return nil -- Abort an ineligible write, including cross-server duplicates.
				end
				nextProfile.coins += DAILY_REWARD
				nextProfile.lastDaily = now
			elseif promoCode then
				if nextProfile.redeemed[promoCode] then
					return nil
				end
				nextProfile.coins += PROMO_CODES[promoCode]
				nextProfile.redeemed[promoCode] = true
			end
			return nextProfile
		end)
	end)
	busy[id] = nil

	if not success then
		warn("[RewardDemo] DataStore update failed: " .. tostring(stored))
		return response(false, "Could not confirm the save; please rejoin and check", current)
	end
	if stored == nil then
		return response(false, "Already claimed or redeemed. Rejoin to refresh status.", current)
	end

	local updated = sanitizedProfile(stored)
	-- Another PlayerRemoving may have run during the DataStore operation.
	if player.Parent == Players then
		profiles[id] = updated
		getCoinsValue(player).Value = updated.coins
	end
	return response(true, if action == "daily" then "+150 coins claimed!" else "Promo code redeemed!", updated)
end