USDC trust line

app/copy-trade/page.tsx

@@ -57,6 +57,7 @@ function CopyTradeContent() {
   const [traceError, setTraceError] = useState<string | null>(null);
   const { data: market } = useMarket(marketIdParam ?? trace?.marketId ?? undefined);
   const onChainMarketId = market?.onChainMarketId ?? null;
+  const onChainMarket = useOnChainMarket(onChainMarketId);
 
   const balance = useUsdcBalance(address);
   const reserve = useAccountReserve(address);
@@ -184,6 +185,24 @@ function CopyTradeContent() {
       setStatusMessage("This market isn't on-chain yet, so it can't be traded.");
       return;
     }
+    if (!onChainMarket.data) {
+      setStatusMessage("Checking the on-chain market and ledger time…");
+      return;
+    }
+    if (!marketCanTrade) {
+      setStatusMessage("This market is closed or too close to its deadline to safely place a trade.");
+      return;
+    }
+    if (!trustlineReady) {
+      setStatusMessage(
+        trustlineMissing
+          ? "Enable your USDC trustline before copying this trade."
+          : trustline.data?.kind === "present"
+            ? "The issuer hasn't authorized your USDC trustline."
+            : "Checking your USDC trustline…",
+      );
+      return;
+    }
     if (!amountRaw || amountRaw <= 0n) {
       setStatusMessage("Choose an allocation greater than zero. You may need USDC in your wallet first.");
       return;
@@ -197,6 +216,17 @@ function CopyTradeContent() {
         return;
       }
 
+      const freshMarket = await fetchOnChainMarket(onChainMarketId);
+      const freshLedgerNow = getLedgerNow();
+      if (
+        freshLedgerNow === null ||
+        freshMarket.market.status.tag !== "Open" ||
+        BigInt(Math.floor(freshLedgerNow)) + BigInt(SAFETY_MARGIN_S + MIN_TX_TIMEOUT_S) >= freshMarket.market.close_time
+      ) {
+        setStatusMessage("This market is closed or too close to its deadline to safely place a trade.");
+        return;
+      }
+
       setStatusMessage("Recording your copy trade…");
       const { copyTradeId } = await initiateCopyTrade({
         traceId: trace.id,
@@ -230,6 +260,16 @@ function CopyTradeContent() {
     }
   };
 
+  const handleEnableUsdc = async () => {
+    setStatusMessage("Checking XLM reserve, then opening your wallet…");
+    try {
+      await enableUsdc.mutateAsync();
+      setStatusMessage("USDC is enabled. Click Confirm Copy Trade when you're ready.");
+    } catch (error) {
+      setStatusMessage(error instanceof Error ? error.message : "Couldn't enable USDC.");
+    }
+  };
+
   return (
     <div className="bg-background text-on-surface min-h-screen flex flex-col">
       <style jsx global>{`

app/markets/quick-view/page.tsx

@@ -87,7 +87,7 @@ function MarketQuickViewContent() {
   const onChainMarketId = market?.onChainMarketId ?? onChainIdParam ?? null;
   const chain = useOnChainMarket(onChainMarketId);
 
-  const { address, isConnected, openModal } = useWallet();
+  const { address, isConnected, isWrongNetwork, openModal } = useWallet();
   const position = usePosition(onChainMarketId, address);
   const balance = useUsdcBalance(address);
   const reserve = useAccountReserve(address);
@@ -102,6 +102,7 @@ function MarketQuickViewContent() {
   const [showModal] = useState(true);
   const [side, setSide] = useState<"Yes" | "No">(initialSide);
   const [amountInput, setAmountInput] = useState("10");
+  const [buyMode, setBuyMode] = useState<"usdc" | "shares">("usdc");
   const [buyStatus, setBuyStatus] = useState<string | null>(null);
   const [reviewModel, setReviewModel] = useState<{ model: ReviewModel; changedFrom?: ReviewModel } | null>(null);
   const reviewResolver = useRef<((approved: boolean) => void) | null>(null);
@@ -161,8 +162,28 @@ function MarketQuickViewContent() {
       return;
     }
     if (!onChainMarketId) return;
+    if (trustlineMissing) {
+      setBuyStatus("Enable your USDC trustline below, then click Buy again.");
+      return;
+    }
+    if (trustlineUnauthorized) {
+      setBuyStatus("The issuer hasn't authorized your USDC trustline.");
+      return;
+    }
+    if (isWrongNetwork) {
+      setBuyStatus("Switch your wallet to Stellar Testnet to place this trade.");
+      return;
+    }
     if (!amountRaw || amountRaw <= 0n) {
-      setBuyStatus("Enter an amount like 10 or 2.5.");
+      setBuyStatus(buyMode === "usdc" ? "Enter an amount like 10 or 2.5." : "Enter a share amount greater than zero.");
+      return;
+    }
+    if (ledger.now === null) {
+      setBuyStatus("Checking market time…");
+      return;
+    }
+    if (!safeToTrade) {
+      setBuyStatus("This market closes too soon to safely place a trade.");
       return;
     }
     setBuyStatus(null);
@@ -183,6 +204,16 @@ function MarketQuickViewContent() {
     }
   };
 
+  const handleEnableUsdc = async () => {
+    setBuyStatus("Checking XLM reserve, then opening your wallet…");
+    try {
+      await enableUsdc.mutateAsync();
+      setBuyStatus("USDC is enabled. Review your amount and click Buy to submit the trade.");
+    } catch (err) {
+      setBuyStatus(err instanceof Error ? err.message : "Couldn't enable USDC.");
+    }
+  };
+
   if (isLoading) {
     return (
       <main className="relative min-h-[calc(100vh-64px)] overflow-hidden bg-surface flex items-center justify-center">
@@ -256,6 +287,7 @@ function MarketQuickViewContent() {
                     {statusLabel}
                     {chainStatus && <SourceTag source="chain" />}
                   </span>
+                  {countdown && <span className="text-[10px] font-data-mono text-on-surface-variant">{countdown}</span>}
                   <span className="font-label-caps text-label-caps text-outline uppercase font-bold tracking-wider">{categoryLabel}</span>
                 </div>
                 <Link 
@@ -336,8 +368,12 @@ function MarketQuickViewContent() {
                 {onChainMarketId !== null && (
                   <div className="space-y-3">
                     <div className="flex items-center gap-3">
+                      <div className="inline-flex rounded border border-outline-variant p-0.5" aria-label="Buy amount unit">
+                        <button type="button" aria-pressed={buyMode === "usdc"} onClick={() => setBuyMode("usdc")} className={`px-2 py-1 text-[10px] rounded ${buyMode === "usdc" ? "bg-primary text-primary-foreground" : "text-on-surface-variant"}`}>USDC</button>
+                        <button type="button" aria-pressed={buyMode === "shares"} onClick={() => setBuyMode("shares")} className={`px-2 py-1 text-[10px] rounded ${buyMode === "shares" ? "bg-primary text-primary-foreground" : "text-on-surface-variant"}`}>Shares</button>
+                      </div>
                       <label htmlFor="buy-amount" className="font-label-caps text-label-caps text-on-surface-variant uppercase text-[10px] shrink-0">
-                        Amount (USDC)
+                        Amount ({buyMode === "usdc" ? "USDC" : `${side.toUpperCase()} shares`})
                       </label>
                       <input
                         id="buy-amount"
@@ -371,8 +407,14 @@ function MarketQuickViewContent() {
                     <div className="flex justify-between text-[11px] font-data-mono text-on-surface-variant">
                       <span>
                         {amountRaw === null
-                          ? "Enter an amount like 10 or 2.5"
-                          : quote.data !== undefined
+                          ? buyMode === "usdc" ? "Enter an amount like 10 or 2.5" : "Enter a share amount"
+                          : buyMode === "shares" && exactQuote.data
+                            ? `Costs ≈ ${formatUsdc(exactQuote.data.collateralIn, { maxDecimals: 2 })} USDC (fee ${formatUsdc(exactQuote.data.fee, { maxDecimals: 2 })}), at most ${formatUsdc(maxIn(exactQuote.data.collateralIn, SLIPPAGE_BPS), { maxDecimals: 2 })} with 1% slippage`
+                            : buyMode === "shares" && exactQuote.error
+                              ? exactQuote.error.message
+                              : buyMode === "shares" && exactQuote.isFetching
+                                ? "Quoting exact share amount…"
+                                : quote.data !== undefined
                             ? `≈ ${formatUsdc(quote.data, { maxDecimals: 2 })} shares, at least ${formatUsdc(minOut(quote.data, SLIPPAGE_BPS), { maxDecimals: 2 })} (1% slippage)`
                             : quote.error ? quote.error.message : quote.isFetching ? "Quoting…" : ""}
                       </span>
@@ -420,6 +462,19 @@ function MarketQuickViewContent() {
                     {!isOpen && view && (
                       <p className="text-[11px] text-on-surface-variant">This market is closed to trading.</p>
                     )}
+                    {ledger.now === null && <p className="text-[11px] text-on-surface-variant">Checking market time…</p>}
+                    {isOpen && !safeToTrade && <p className="text-[11px] text-on-surface-variant">Trading is disabled this close to the market deadline.</p>}
+                    {trustlineMissing && !isWrongNetwork && (
+                      <div className="rounded-lg border border-outline-variant bg-surface-container-low p-3 space-y-2">
+                        <p className="text-xs text-on-surface-variant">
+                          Enable USDC once to buy on Stellar. This creates a trustline and locks one base reserve (typically 0.5 XLM); it does not submit your trade.
+                        </p>
+                        <button type="button" onClick={handleEnableUsdc} disabled={enableUsdc.isPending} className="bg-primary text-primary-foreground px-3 py-2 rounded-lg text-xs font-bold disabled:opacity-50">
+                          {enableUsdc.isPending ? "Enabling…" : "Enable USDC"}
+                        </button>
+                      </div>
+                    )}
+                    {trustlineUnauthorized && <p className="text-[11px] text-error">The issuer hasn&apos;t authorized your USDC trustline.</p>}
                     {position.data && (position.data.yes > 0n || position.data.no > 0n) && (
                       <p className="text-[11px] font-data-mono text-on-surface">
                         Your position: {formatUsdc(position.data.yes, { maxDecimals: 2 })} YES · {formatUsdc(position.data.no, { maxDecimals: 2 })} NO

components/layout/WalletDropdown.tsx

@@ -3,7 +3,7 @@
 import React, { useState, useRef, useEffect } from "react";
 import { motion, AnimatePresence } from "framer-motion";
 import { useWallet } from "@/lib/contexts/WalletContext";
-import { useUsdcBalance } from "@/lib/hooks/useStellar";
+import { useEnableUsdc, useUsdcBalance, useUsdcTrustline } from "@/lib/hooks/useStellar";
 import { NETWORK_LABEL, explorerAccount } from "@/lib/stellar/config";
 import { formatUsdc, shortAddress } from "@/lib/stellar/units";
 
@@ -13,6 +13,8 @@ const WalletDropdown = () => {
   const [copied, setCopied] = useState(false);
   const dropdownRef = useRef<HTMLDivElement>(null);
   const balance = useUsdcBalance(address);
+  const trustline = useUsdcTrustline(address);
+  const enableUsdc = useEnableUsdc();
 
   // Close dropdown when clicking outside
   useEffect(() => {
@@ -39,10 +41,22 @@ const WalletDropdown = () => {
   }
 
   const truncatedAddress = shortAddress(address, 6, 4);
-  const balanceText = balance.data !== undefined
+  const trustlineMissing = !isWrongNetwork && trustline.data?.kind === "missing";
+  const unauthorized = trustline.data?.kind === "present" && !trustline.data.authorized;
+  const balanceText = trustlineMissing
+    ? "USDC not enabled"
+    : balance.data !== undefined
     ? formatUsdc(balance.data, { maxDecimals: 2, minDecimals: 2, grouping: true })
     : balance.isError ? "—" : "…";
 
+  const handleEnableUsdc = async () => {
+    try {
+      await enableUsdc.mutateAsync();
+    } catch {
+      // The mutation error is rendered in the wallet menu below.
+    }
+  };
+
   const copyAddress = async () => {
     try {
       await navigator.clipboard.writeText(address);
@@ -101,6 +115,22 @@ const WalletDropdown = () => {
                   USDC
                 </span>
               </div>
+              {trustlineMissing && !isWrongNetwork && (
+                <button
+                  type="button"
+                  onClick={handleEnableUsdc}
+                  disabled={enableUsdc.isPending}
+                  className="mt-2 rounded-md bg-primary px-3 py-1.5 text-xs font-bold text-primary-foreground disabled:opacity-50"
+                >
+                  {enableUsdc.isPending ? "Enabling…" : "Enable USDC"}
+                </button>
+              )}
+              {unauthorized && (
+                <p className="mt-2 text-[11px] text-error">The issuer hasn&apos;t authorized your USDC trustline.</p>
+              )}
+              {enableUsdc.error && (
+                <p className="mt-2 text-[11px] text-error">{enableUsdc.error.message}</p>
+              )}
               {isWrongNetwork && (
                 <p className="mt-2 text-[11px] text-error">Your wallet is on a different network. Switch it to Stellar Testnet.</p>
               )}

docs/contract-requests.md

@@ -47,3 +47,11 @@ the commitment hash has to rebuild the XDR by hand. A no-op view function
 that takes a `ResolutionSpec`, or a `spec_hash(spec) -> BytesN<32>` view,
 would put the type in the spec and let clients ask the contract for the
 hash instead of re-implementing it.
+
+## 5. Add a share-budget sell quote
+
+The frontend converts "sell N shares" into `collateral_out` by binary-searching
+the contract's integer-rounded `calc_sell` math, then confirms the result with
+`quote_sell`. A view such as `quote_sell_shares(market_id, outcome, shares) ->
+{ collateral_out, shares_in }` would provide the exact inversion on-chain and
+avoid repeated local work and quote simulations.

docs/manual-test.md

@@ -6,7 +6,7 @@ These steps cover what automated checks can't: a real browser wallet signing rea
 
 ## Before you start: two known blockers
 
-1. **Test USDC can only be minted by the deployer key.** The collateral is a self-issued test asset (`USDC` issued by `GD2NB2VUME7ECMHFHQN5M3KUZLLJF3R6Z4OFCBLE4SJNHIQHITRPQGHQ`, wrapped as the SAC `CA2WQQJ4OHQCLHQW6XN4BCLILGRV6V4YDYDT3GVIWXB53BTOO7EMREQH`). There is no faucet, so step 4 needs a maintainer (see [contract-requests.md](contract-requests.md) #3).
+1. **Test USDC can only be minted by the deployer key.** The collateral is a self-issued test asset wrapped as a Stellar Asset Contract. There is no faucet, so step 4 still needs a maintainer (see [contract-requests.md](contract-requests.md) #3).
 2. **Both existing testnet markets are closed.** Markets 0 and 1 were created by the contracts repo's demo with a 90-second trading window on 2026-09-21; market 0 is resolved YES. Buying on them fails with "This market has closed". Step 7 therefore needs a fresh, open market (see below).
 
 ## You need
@@ -31,9 +31,11 @@ These steps cover what automated checks can't: a real browser wallet signing rea
 
 ## 4. Get test USDC
 
-a. **Add the trustline** (the account must trust the asset before it can hold it):
+a. **Enable the trustline in OracleDesk** (the account must trust the asset before it can hold it):
 
-- [ ] Freighter → Manage assets → Add manually: code `USDC`, issuer `GD2NB2VUME7ECMHFHQN5M3KUZLLJF3R6Z4OFCBLE4SJNHIQHITRPQGHQ`. Approve the transaction.
+- [ ] Connect your funded wallet, then open the wallet menu or an on-chain market's quick view.
+- [ ] Click **Enable USDC** and approve the one-time `changeTrust` transaction. The flow checks spendable XLM for the trustline reserve and transaction fee first.
+- [ ] Wait for the trustline to appear. Enabling it does not submit a pending buy; review the amount and click **Buy** again.
 
 b. **Ask a maintainer to mint.** With the deployer key from `scripts/deploy-testnet.sh` (the CLI identity `oracledesk-deployer`), they run: