[www] I award you no points

apps/www/src/client/App.tsx

@@ -1194,7 +1194,13 @@ function StaffPlayerActions({ account, navigate }: { account: PublicAccount; nav
 							json: { amount },
 						})
 						setTokens('')
-						return `Sent ${amount.toLocaleString()} tokens. @${account.username} now has ${res.balance.toLocaleString()}.`
+						const what =
+							amount < 0
+								? `Took ${Math.abs(amount).toLocaleString()} tokens back`
+								: amount === 0
+									? 'Sent an empty box'
+									: `Sent ${amount.toLocaleString()} tokens`
+						return `${what}. @${account.username} now has ${res.balance.toLocaleString()}.`
 					})
 				}}
 			>
@@ -1203,9 +1209,7 @@ function StaffPlayerActions({ account, navigate }: { account: PublicAccount; nav
 					<span className="staff-gift">
 						<input
 							type="number"
-							min={1}
 							step={1}
-							inputMode="numeric"
 							value={tokens}
 							required
 							onChange={(e) => setTokens(e.target.value)}
@@ -1215,7 +1219,9 @@ function StaffPlayerActions({ account, navigate }: { account: PublicAccount; nav
 						</button>
 					</span>
 					<span className="hint">
-						Arrives as a gift box, and is added to their balance right away.
+						Arrives as a gift box, and is added to their balance right away. A negative amount takes
+						tokens back instead — it still sends a box, and it can&apos;t take more than they have.
+						Zero sends an empty box and moves nothing.
 					</span>
 				</label>
 				{gift.error && <p className="error">{gift.error}</p>}

apps/www/src/staff.ts

@@ -36,6 +36,8 @@ import {
 	CurrencyType,
 	DEFAULT_STARTING_TOKENS,
 	ensureStartingBalances,
+	getBalance,
+	spendCurrency,
 } from '../../econ/src/balance-db'
 import { grantCustomAvatarItem, ownedCustomAvatarItemIds } from '../../econ/src/inventory-custom-db'
 // The notification ids and the kick frame's recovered shape, owned by `notify`. Both are
@@ -647,7 +649,8 @@ async function announceGift(
 }
 
 /**
- * Send a player RecCenterTokens in a gift box.
+ * Send a player RecCenterTokens in a gift box — or, with a NEGATIVE amount, take some back.
+ *
  *
  * The same shape as econ's own server-handed currency (a game reward's Laser Tag tickets):
  * the balance is CREDITED here — opening a box only deletes it, it grants nothing — then a
@@ -658,6 +661,11 @@ async function announceGift(
  *
  * Both frames are best-effort: the tokens are banked by the time they go out, and an offline
  * player meets the box in `GET /api/avatar/v2/gifts` and the balance on their next read.
+ *
+ * A negative amount debits through the same guarded spend a purchase uses, so it cannot
+ * overdraw: a player who can't afford it is refused and keeps what they have. Zero moves
+ * nothing at all. Both still mint a box, carrying that `Currency` — nobody has seen what the
+ * client makes of an empty or a negative one, and finding out is the point.
  */
 export async function giftTokensHandler(c: Context<App>) {
 	const playerId = playerIdParam(c)
@@ -665,11 +673,11 @@ export async function giftTokensHandler(c: Context<App>) {
 
 	const body = (await c.req.json().catch(() => ({}))) as { amount?: unknown }
 	const amount = Number(body.amount)
-	if (!Number.isInteger(amount) || amount <= 0) {
-		return c.json({ error: 'Enter a whole number of tokens greater than 0' }, 400)
+	if (!Number.isInteger(amount)) {
+		return c.json({ error: 'Enter a whole number of tokens, positive or negative' }, 400)
 	}
 	const maxGift = intVar(c.env.MAX_TOKEN_GIFT, DEFAULT_MAX_TOKEN_GIFT)
-	if (amount > maxGift) {
+	if (Math.abs(amount) > maxGift) {
 		return c.json({ error: `A gift can carry at most ${maxGift.toLocaleString()} tokens` }, 400)
 	}
 	if ((await getAccount(c.env.DB, playerId)) === null) {
@@ -680,13 +688,38 @@ export async function giftTokensHandler(c: Context<App>) {
 	// and a never-touched balance would otherwise start from this gift instead of the grant.
 	const startingTokens = intVar(c.env.STARTING_TOKENS, DEFAULT_STARTING_TOKENS)
 	await ensureStartingBalances(c.env.DB, playerId, startingTokens)
-	const balance = await creditCurrency(
-		c.env.DB,
-		playerId,
-		CurrencyType.RecCenterTokens,
-		amount,
-		startingTokens
-	)
+	// A NEGATIVE amount takes tokens back, through the same guarded debit a purchase spends
+	// with — so it can't overdraw, and a player who can't afford it keeps what they have.
+	if (amount < 0) {
+		const spent = await spendCurrency(
+			c.env.DB,
+			playerId,
+			CurrencyType.RecCenterTokens,
+			-amount,
+			startingTokens
+		)
+		if (!spent) {
+			const held = await getBalance(
+				c.env.DB,
+				playerId,
+				CurrencyType.RecCenterTokens,
+				startingTokens
+			)
+			return c.json({ error: `They only have ${held.toLocaleString()} tokens to take` }, 400)
+		}
+	}
+	// Zero moves nothing and still sends a box — an empty one, for the same reason a negative
+	// one is allowed: nobody has seen what the client draws for it.
+	const balance =
+		amount > 0
+			? await creditCurrency(
+					c.env.DB,
+					playerId,
+					CurrencyType.RecCenterTokens,
+					amount,
+					startingTokens
+				)
+			: await getBalance(c.env.DB, playerId, CurrencyType.RecCenterTokens, startingTokens)
 
 	const content = staffGiftContent({
 		CurrencyType: CurrencyType.RecCenterTokens,
@@ -695,7 +728,11 @@ export async function giftTokensHandler(c: Context<App>) {
 	const gift = await createGift(c.env.DB, playerId, content)
 
 	await recordPlayerAudit(c, 'gift_tokens', { playerId, amount, balance, giftId: gift.id })
-	logger.info('staff gifted tokens', { moderatorId: staffId(c), playerId, amount })
+	logger.info(amount < 0 ? 'staff took tokens back' : 'staff gifted tokens', {
+		moderatorId: staffId(c),
+		playerId,
+		amount,
+	})
 
 	// The balance first, so the box's announcement lands on a total that already includes it.
 	try {

apps/www/src/test/integration/api.test.ts

@@ -1339,9 +1339,11 @@ it('gifts a player tokens in a gift box', async () => {
 	])
 })
 
-it('refuses a token gift that is not a positive whole number, too large, or to nobody', async () => {
+it('refuses a token gift that is not a whole number, too large, or to nobody', async () => {
 	await updateAccount(env.DB, 8301, { username: 'NotGifted' })
-	for (const amount of [0, -5, 1.5, 'lots', 10_001]) {
+	// A fraction and a word are not amounts, and the cap binds in both directions, since a
+	// negative gift takes tokens away. Zero is allowed — see the empty box below.
+	for (const amount of [1.5, 'lots', 10_001, -10_001]) {
 		const res = await staffPost('/api/staff/players/8301/gift-tokens', 8110, { amount })
 		expect(res.status).toBe(400)
 	}
@@ -1352,6 +1354,73 @@ it('refuses a token gift that is not a positive whole number, too large, or to n
 	expect(await auditRows('gift_tokens', 8301)).toEqual([])
 })
 
+// A negative gift takes tokens back — through the same guarded debit a purchase spends with,
+// so it cannot overdraw. It still mints a box, carrying the negative amount: what the client
+// makes of one is the thing being found out.
+it('takes tokens back on a negative gift, and cannot overdraw', async () => {
+	const hub = () => env.RECFLARE_NOTIFICATIONS_HUB.getByName('global')
+	await hub().fetch('http://do/all', { method: 'DELETE' })
+	await updateAccount(env.DB, 8360, { username: 'Indebted' })
+
+	const res = await staffPost('/api/staff/players/8360/gift-tokens', 8110, { amount: -400 })
+	expect(res.status).toBe(200)
+	const body = (await res.json()) as { balance: number; giftId: number }
+	expect(body.balance).toBe(DEFAULT_STARTING_TOKENS - 400)
+	await expect(
+		getBalance(env.DB, 8360, CurrencyType.RecCenterTokens, DEFAULT_STARTING_TOKENS)
+	).resolves.toBe(DEFAULT_STARTING_TOKENS - 400)
+
+	const gifts = await getPendingGifts(env.DB, 8360)
+	expect(gifts).toHaveLength(1)
+	expect(gifts[0]).toMatchObject({ Id: body.giftId, Currency: -400 })
+
+	// The balance frame carries the resulting total, as it does for a credit.
+	const frames = (await (await hub().fetch('http://do/all')).json()) as Array<{
+		notificationType: number
+		data: Record<string, unknown>
+	}>
+	expect(frames[0].data).toMatchObject({ Balance: DEFAULT_STARTING_TOKENS - 400 })
+
+	expect(await auditRows('gift_tokens', 8360)).toEqual([
+		{
+			actor: 8110,
+			data: {
+				playerId: 8360,
+				amount: -400,
+				balance: DEFAULT_STARTING_TOKENS - 400,
+				giftId: body.giftId,
+			},
+		},
+	])
+
+	// More than they hold changes nothing: no debit, no box, no audit row beyond the first.
+	// Under the cap, so this is the BALANCE refusing it and not the typo guard (they hold
+	// DEFAULT_STARTING_TOKENS - 400 by now).
+	const tooMuch = await staffPost('/api/staff/players/8360/gift-tokens', 8110, {
+		amount: -(DEFAULT_STARTING_TOKENS - 100),
+	})
+	expect(tooMuch.status).toBe(400)
+	await expect(
+		getBalance(env.DB, 8360, CurrencyType.RecCenterTokens, DEFAULT_STARTING_TOKENS)
+	).resolves.toBe(DEFAULT_STARTING_TOKENS - 400)
+	expect(await getPendingGifts(env.DB, 8360)).toHaveLength(1)
+	expect(await auditRows('gift_tokens', 8360)).toHaveLength(1)
+})
+
+// Zero is a real gift here: nothing moves, and the player gets an empty box.
+it('sends an empty box on a zero token gift', async () => {
+	await updateAccount(env.DB, 8361, { username: 'Emptyhanded' })
+	const res = await staffPost('/api/staff/players/8361/gift-tokens', 8110, { amount: 0 })
+	expect(res.status).toBe(200)
+	const body = (await res.json()) as { balance: number; giftId: number }
+	expect(body.balance).toBe(DEFAULT_STARTING_TOKENS)
+
+	const gifts = await getPendingGifts(env.DB, 8361)
+	expect(gifts).toHaveLength(1)
+	expect(gifts[0]).toMatchObject({ Id: body.giftId, Currency: 0 })
+	expect(await auditRows('gift_tokens', 8361)).toMatchObject([{ data: { amount: 0 } }])
+})
+
 // An account that has never renamed itself stores no count and is read as the default 3, so
 // the first grant makes it 4 rather than 1.
 it('adds a username change on top of the default', async () => {