feat: add offer account support (MVP)

app/features/accounts/account-hooks.ts

@@ -12,13 +12,13 @@ import type { AgicashDbAccountWithProofs } from '../agicash-db/database';
 import { useUser } from '../user/user-hooks';
 import {
   type Account,
-  type AccountPurpose,
   type AccountType,
   type CashuAccount,
   type ExtendedAccount,
   type SparkAccount,
   getAccountBalance,
 } from './account';
+import type { AccountPurpose } from '~/lib/cashu/protocol-extensions';
 import {
   type AccountRepository,
   useAccountRepository,
@@ -165,15 +165,15 @@ export const accountsQueryOptions = ({
 type UseAccountsSelect<
   T extends AccountType = AccountType,
   P extends AccountPurpose = AccountPurpose,
-> = P extends 'gift-card'
+> = P extends 'gift-card' | 'offer'
   ? {
       /** Filter by currency (e.g., 'BTC', 'USD') */
       currency?: Currency;
-      /** Must be 'cashu' when purpose is 'gift-card'. */
+      /** Must be 'cashu' when purpose is 'gift-card' or 'offer'. */
       type?: 'cashu';
       /** Filter by online status */
       isOnline?: boolean;
-      /** Filter for gift-card accounts. Returns `CashuAccount[]` since gift cards are always cashu. */
+      /** Filter for gift-card or offer accounts. Returns `CashuAccount[]` since these are always cashu. */
       purpose: P;
     }
   : {
@@ -190,6 +190,9 @@ type UseAccountsSelect<
 export function useAccounts(
   select: UseAccountsSelect<'cashu', 'gift-card'>,
 ): UseSuspenseQueryResult<ExtendedAccount<'cashu'>[]>;
+export function useAccounts(
+  select: UseAccountsSelect<'cashu', 'offer'>,
+): UseSuspenseQueryResult<ExtendedAccount<'cashu'>[]>;
 export function useAccounts<
   T extends AccountType = AccountType,
   P extends AccountPurpose = AccountPurpose,
@@ -366,10 +369,15 @@ export function useAddCashuAccount() {
   const accountCache = useAccountsCache();
   const accountService = useAccountService();
 
+  type AddAccountParams = Parameters<typeof accountService.addCashuAccount>[0];
   const { mutateAsync } = useMutation({
-    mutationFn: async (
-      account: Parameters<typeof accountService.addCashuAccount>[0]['account'],
-    ) => accountService.addCashuAccount({ userId, account }),
+    mutationFn: async ({
+      account,
+      mintInfo,
+    }: {
+      account: AddAccountParams['account'];
+      mintInfo?: AddAccountParams['mintInfo'];
+    }) => accountService.addCashuAccount({ userId, account, mintInfo }),
     onSuccess: (account) => {
       // We add the account as soon as it is created so that it is available in the cache immediately.
       // This is important when using other hooks that are trying to use the account immediately after it is created.

app/features/accounts/account-repository.ts

@@ -122,6 +122,7 @@ export class AccountRepository {
         mint_url: accountInput.mintUrl,
         is_test_mint: accountInput.isTestMint,
         keyset_counters: accountInput.keysetCounters,
+        expires_at: accountInput.expiresAt,
       } satisfies z.input<typeof CashuAccountDetailsDbDataSchema>);
     } else {
       details = SparkAccountDetailsDbDataSchema.parse({
@@ -134,7 +135,8 @@ export class AccountRepository {
       currency: accountInput.currency,
       details,
       user_id: accountInput.userId,
-      purpose: accountInput.purpose,
+      // Cast needed until migration adds 'offer' to DB enum and types are regenerated
+      purpose: accountInput.purpose as 'transactional' | 'gift-card',
     };
 
     const query = this.db
@@ -192,6 +194,7 @@ export class AccountRepository {
         mintUrl: details.mint_url,
         isTestMint: details.is_test_mint,
         keysetCounters: details.keyset_counters,
+        expiresAt: details.expires_at ?? null,
         proofs,
         wallet,
       } as T;

app/features/accounts/account-service.ts

@@ -1,5 +1,5 @@
 import type { DistributedOmit } from 'type-fest';
-import { checkIsTestMint } from '~/lib/cashu';
+import { type ExtendedMintInfo, checkIsTestMint } from '~/lib/cashu';
 import type { User } from '../user/user';
 import type { Account, CashuAccount, ExtendedAccount } from './account';
 import {
@@ -42,6 +42,7 @@ export class AccountService {
   async addCashuAccount({
     userId,
     account,
+    mintInfo,
   }: {
     userId: string;
     account: DistributedOmit<
@@ -55,8 +56,9 @@ export class AccountService {
       | 'wallet'
       | 'isOnline'
     >;
+    mintInfo?: ExtendedMintInfo;
   }) {
-    const isTestMint = await checkIsTestMint(account.mintUrl);
+    const isTestMint = await checkIsTestMint(account.mintUrl, mintInfo);
 
     return this.accountRepository.create<CashuAccount>({
       ...account,

app/features/accounts/account.ts

@@ -4,18 +4,12 @@ import type {
 } from '@buildonspark/spark-sdk';
 import type { DistributedOmit } from 'type-fest';
 import { type ExtendedCashuWallet, getCashuUnit, sumProofs } from '~/lib/cashu';
+import type { AccountPurpose } from '~/lib/cashu/protocol-extensions';
 import { type Currency, Money } from '~/lib/money';
 import type { CashuProof } from './cashu-account';
 
 export type AccountType = 'cashu' | 'spark';
 
-/**
- * The purpose of this account.
- * - 'transactional': Regular accounts for sending/receiving payments
- * - 'gift-card': Closed-loop accounts for mints that are issuing gift cards
- */
-export type AccountPurpose = 'transactional' | 'gift-card';
-
 export type Account = {
   id: string;
   name: string;
@@ -38,6 +32,11 @@ export type Account = {
        * Holds counter value for each mint keyset. Key is the keyset id, value is counter value.
        */
       keysetCounters: Record<string, number>;
+      /**
+       * Unix timestamp when the account's ecash expires (for offer accounts).
+       * Derived from the active keyset's `final_expiry` field.
+       */
+      expiresAt: number | null;
       /**
        * Holds all cashu proofs for the account.
        * Amounts are denominated in the cashu units (e.g. sats for BTC accounts, cents for USD accounts).
@@ -77,7 +76,7 @@ export type RedactedCashuAccount = Extract<RedactedAccount, { type: 'cashu' }>;
 
 /**
  * Returns true if the account can send payments through the Lightning network.
- * Returns false for test mints and gift-card accounts.
+ * Returns false for test mints, gift-card accounts, and offer accounts.
  */
 export const canSendToLightning = (account: Account): boolean => {
   if (account.type === 'spark') {
@@ -88,10 +87,13 @@ export const canSendToLightning = (account: Account): boolean => {
 
 /**
  * Returns true if the account can receive payments via the Lightning network.
- * Returns false for test mints only.
+ * Returns false for offline wallets, test mints, and mints with minting disabled (NUT-04).
  */
 export const canReceiveFromLightning = (account: Account): boolean => {
-  return account.type === 'spark' || !account.isTestMint;
+  if (account.type === 'spark') return true;
+  if (!account.isOnline) return false;
+  if (account.isTestMint) return false;
+  return !account.wallet.getMintInfo().isSupported(4).disabled;
 };
 
 export const getAccountBalance = (account: Account) => {

app/features/agicash-db/json-models/cashu-account-details-db-data.ts

@@ -13,6 +13,12 @@ export const CashuAccountDetailsDbDataSchema = z.object({
    * Holds counter value for each mint keyset. Key is the keyset id, value is counter value.
    */
   keyset_counters: z.record(z.string(), z.number()),
+  /**
+   * Unix timestamp when the account's ecash expires (for offer accounts).
+   * Derived from the active keyset's `final_expiry` field.
+   * Null for non-offer accounts or when the keyset has no expiry.
+   */
+  expires_at: z.number().nullable().optional(),
 });
 
 export type CashuAccountDetailsDbData = z.infer<

app/features/gift-cards/add-gift-card.tsx

@@ -34,11 +34,14 @@ function useAddGiftCard() {
 
   return ({ name, currency, url }: AddGiftCardParams) =>
     addCashuAccount({
-      name,
-      currency,
-      mintUrl: url,
-      type: 'cashu',
-      purpose: 'gift-card',
+      account: {
+        name,
+        currency,
+        mintUrl: url,
+        type: 'cashu',
+        purpose: 'gift-card',
+        expiresAt: null,
+      },
     });
 }
 

app/features/gift-cards/gift-cards.tsx

@@ -16,13 +16,22 @@ import {
 import { DiscoverGiftCards } from './discover-gift-cards';
 import { EmptyState } from './empty-state';
 import { GiftCardItem } from './gift-card-item';
+import { OfferItem } from './offer-item';
 import {
   getGiftCardImageByUrl,
   useDiscoverGiftCards,
 } from './use-discover-cards';
 
+function useActiveOffers() {
+  const { data: offerAccounts } = useAccounts({ purpose: 'offer' });
+  const now = Date.now() / 1000;
+  return offerAccounts.filter(
+    (account) => !account.expiresAt || account.expiresAt > now,
+  );
+}
+
 /**
- * Gift cards view with discover section and card stack.
+ * Gift cards view with discover section, card stack, and offers.
  * Clicking a card navigates to the card details page with view transitions.
  */
 export function GiftCards() {
@@ -37,6 +46,7 @@ export function GiftCards() {
   const stackedHeight =
     CARD_HEIGHT + (accounts.length - 1) * VERTICAL_CARD_OFFSET_IN_STACK;
   const giftCardsToDiscover = useDiscoverGiftCards();
+  const activeOffers = useActiveOffers();
 
   const handleCardClick = (account: CashuAccount) => {
     navigate(`/gift-cards/${account.id}`, { viewTransition: true });
@@ -91,6 +101,20 @@ export function GiftCards() {
           ) : (
             <EmptyState />
           )}
+
+          {activeOffers.length > 0 && (
+            <div className="flex w-full shrink-0 flex-col items-center px-4 pb-8">
+              <h2 className="mb-3 w-full text-white">Offers</h2>
+              <div
+                className="flex w-full flex-col gap-3"
+                style={{ maxWidth: CARD_WIDTH }}
+              >
+                {activeOffers.map((account) => (
+                  <OfferItem key={account.id} account={account} />
+                ))}
+              </div>
+            </div>
+          )}
         </div>
       </PageContent>
     </Page>

app/features/gift-cards/offer-item.tsx

@@ -0,0 +1,56 @@
+import { MoneyDisplay } from '~/components/money-display';
+import {
+  WalletCard,
+  WalletCardBlank,
+  WalletCardOverlay,
+} from '~/components/wallet-card';
+import {
+  type CashuAccount,
+  getAccountBalance,
+} from '~/features/accounts/account';
+import { getDefaultUnit } from '../shared/currencies';
+
+type OfferItemProps = {
+  account: CashuAccount;
+};
+
+function formatExpiryDate(expiresAt: number): string {
+  const date = new Date(expiresAt * 1000);
+  return date.toLocaleDateString(undefined, {
+    month: 'short',
+    day: 'numeric',
+    year: 'numeric',
+  });
+}
+
+export function OfferItem({ account }: OfferItemProps) {
+  const balance = getAccountBalance(account);
+
+  return (
+    <WalletCard className="w-full max-w-none">
+      <WalletCardBlank />
+      <WalletCardOverlay>
+        <div className="flex h-full flex-col justify-between p-5">
+          <div className="flex items-center justify-between">
+            <span className="text-lg text-white drop-shadow-md">
+              {account.name}
+            </span>
+            {balance && (
+              <MoneyDisplay
+                money={balance}
+                size="sm"
+                unit={getDefaultUnit(account.currency)}
+                className="text-white drop-shadow-md"
+              />
+            )}
+          </div>
+          {account.expiresAt && (
+            <p className="text-sm text-white/60">
+              Expires {formatExpiryDate(account.expiresAt)}
+            </p>
+          )}
+        </div>
+      </WalletCardOverlay>
+    </WalletCard>
+  );
+}

app/features/receive/receive-cashu-token-hooks.ts

@@ -218,7 +218,7 @@ export function useReceiveCashuTokenAccounts(
   ): Promise<Account> => {
     let newAccount: Account;
     if (accountToAdd.type === 'cashu') {
-      newAccount = await addCashuAccount(accountToAdd);
+      newAccount = await addCashuAccount({ account: accountToAdd });
     } else {
       // Only cashu accounts can be unknown, this should never happen
       throw new Error('Invalid account type');

app/features/receive/receive-cashu-token-service.ts

@@ -41,16 +41,27 @@ export class ReceiveCashuTokenService {
       undefined,
     );
 
+    const purpose = wallet.purpose;
+    let expiresAt: number | null = null;
+    if (purpose === 'offer' && isOnline) {
+      const unit = getCashuProtocolUnit(currency);
+      const activeKeyset = wallet.keyChain
+        .getKeysets()
+        .find((ks) => ks.unit === unit && ks.isActive);
+      expiresAt = activeKeyset?.expiry ?? null;
+    }
+
     const baseAccount = {
       id: 'cashu-account-placeholder-id',
       type: 'cashu' as const,
-      purpose: wallet.purpose,
+      purpose,
       name: mintUrl.replace('https://', '').replace('http://', ''),
       mintUrl,
       createdAt: new Date().toISOString(),
       currency,
       version: 0,
       keysetCounters: {},
+      expiresAt,
       proofs: [],
       isDefault: false,
       isSource: true,
@@ -77,7 +88,7 @@ export class ReceiveCashuTokenService {
     );
 
     const isTestMint = await this.queryClient.fetchQuery(
-      isTestMintQueryOptions(mintUrl),
+      isTestMintQueryOptions(mintUrl, mintInfo),
     );
 
     const isValid = validationResult === true;

app/features/receive/receive-input.tsx

@@ -1,4 +1,3 @@
-import { getEncodedToken } from '@cashu/cashu-ts';
 import { Clipboard, Scan } from 'lucide-react';
 import { MoneyInputDisplay } from '~/components/money-display';
 import { Numpad } from '~/components/numpad';
@@ -22,7 +21,7 @@ import { useMoneyInput } from '~/hooks/use-money-input';
 import { useRedirectTo } from '~/hooks/use-redirect-to';
 import { useBuildLinkWithSearchParams } from '~/hooks/use-search-params-link';
 import { useToast } from '~/hooks/use-toast';
-import { extractCashuToken } from '~/lib/cashu';
+import { extractCashuTokenString } from '~/lib/cashu';
 import { readClipboard } from '~/lib/read-clipboard';
 import {
   LinkWithViewTransition,
@@ -91,8 +90,8 @@ export default function ReceiveInput() {
       return;
     }
 
-    const token = extractCashuToken(clipboardContent);
-    if (!token) {
+    const tokenString = extractCashuTokenString(clipboardContent);
+    if (!tokenString) {
       toast({
         title: 'Invalid input',
         description: 'Please paste a valid cashu token',
@@ -101,8 +100,7 @@ export default function ReceiveInput() {
       return;
     }
 
-    const encodedToken = getEncodedToken(token);
-    const hash = `#${encodedToken}`;
+    const hash = `#${tokenString}`;
 
     // The hash needs to be set manually before navigating or clientLoader of the destination route won't see it
     // See https://github.com/remix-run/remix/discussions/10721