Co-operative exit takes the ticked coins: a subset on the Manage page goes on-chain as exactly those coins

Adam, 2026-10-23: the checkboxes only fed Renew; the exit button always prefilled the whole balance. The manager's offboard always took a coin list, and the fee quote prices each coin by its own expiry, so the page now passes the selection through: the card says which coins will move and prices their total, the exit form shows "N selected coins · amount" instead of an amount field, the quote is for those coins, and no fresh coin is split off first. Nothing ticked (or everything) still means the whole balance, with the editable amount as before.

Co-Authored-By: Claude Fable 5.1 <[email protected]>

3 files changed, 53 insertions, 22 deletions

diff --git a/src/features/ark.js b/src/features/ark.js
index 984c6a2..1c57cd6 100644
--- a/src/features/ark.js
+++ b/src/features/ark.js
@@ -2578,17 +2578,26 @@ export function arkFeature(ctx) {
             : selCoins.length < spend.length
               ? t('arkCoinsRenewSome', { n: selCoins.length, fee: selFee > 0 ? fmtSats(selFee) + ' sats' : t('arkDepthFree') })
               : selFee > 0 ? t('arkCoinsRenewNowFee', { fee: fmtSats(selFee) + ' sats' }) : t('arkDepthRenewBtn'))),
-      h('div', { class: 'card col', style: 'gap:8px' },
-        h('h4', { style: 'margin:0' }, t('arkCoinsCoopTitle')),
-        h('p', { class: 'small muted', style: 'margin:0' }, t('arkCoopDesc')),
-        h('button', { class: 'btn-primary btn-block', disabled: !!ui.arkBusy || !spendableSat || wallet.watchOnly, onClick: () => {
-          const address = wallet.freshReceive().address;
-          ui.arkCoinsPage = null; ui.arkCoinsSel = null; ui.arkExitPage = null; ui.arkExitConfirm = null; ui.arkRenewConfirm = null;
-          ui.arkOffboarded = null; ui.arkError = '';
-          ctx.showSend({ fresh: true });
-          ui.arkOffboardSend = { address, amount: String(spendableSat), fromCoins: true };
-          render();
-        } }, t('arkOffboardBtn', { n: fmtAmount(spendableSat) + ' ' + unitLabel() }))),
+      // The ticked coins are what leaves: a subset goes on-chain as exactly
+      // those coins (no fresh coin split off the whole balance first), all
+      // of them — or nothing ticked — means the whole balance as before.
+      (() => {
+        const subset = selCoins.length > 0 && selCoins.length < spend.length;
+        const coopSat = subset ? selCoins.reduce((n, v) => n + v.amountSat, 0) : spendableSat;
+        return h('div', { class: 'card col', style: 'gap:8px' },
+          h('h4', { style: 'margin:0' }, t('arkCoinsCoopTitle')),
+          h('p', { class: 'small muted', style: 'margin:0' }, t('arkCoopDesc')),
+          subset ? h('p', { class: 'small muted', style: 'margin:0' }, selCoins.length === 1 ? t('arkCoopSelectedOne') : t('arkCoopSelected', { n: selCoins.length })) : null,
+          h('button', { class: 'btn-primary btn-block ark-coop-go', disabled: !!ui.arkBusy || !coopSat || wallet.watchOnly, onClick: () => {
+            const address = wallet.freshReceive().address;
+            const vtxoIds = subset ? selCoins.map((v) => v.id) : undefined;
+            ui.arkCoinsPage = null; ui.arkCoinsSel = null; ui.arkExitPage = null; ui.arkExitConfirm = null; ui.arkRenewConfirm = null;
+            ui.arkOffboarded = null; ui.arkError = '';
+            ctx.showSend({ fresh: true });
+            ui.arkOffboardSend = { address, amount: String(coopSat), fromCoins: true, vtxoIds };
+            render();
+          } }, t('arkOffboardBtn', { n: fmtAmount(coopSat) + ' ' + unitLabel() })));
+      })(),
       h('div', { class: 'card col', style: 'gap:8px' },
         h('h4', { style: 'margin:0' }, t('arkCoinsExitTitle')),
         h('p', { class: 'small muted', style: 'margin:0' },
@@ -3132,7 +3141,7 @@ export function arkFeature(ctx) {
   async function quoteOffboard(o, address) {
     o.quoteFor = address; o.quote = null;
     let quote = null;
-    try { quote = await (await connectArk()).offboardQuote(addrScript(address)); }
+    try { quote = await (await connectArk()).offboardQuote(addrScript(address), o.vtxoIds); }
     catch {} // no quote: the send itself still says what went wrong
     if (o.quoteFor !== address) return; // the address changed meanwhile
     o.quote = quote; o.quoteDone = true;
@@ -3140,7 +3149,9 @@ export function arkFeature(ctx) {
   }
   function arkOffboardSendView() {
     const o = ui.arkOffboardSend;
-    const spendable = arkBalance()?.spendableSat || 0;
+    // chosen coins: the amount is theirs and is not a field
+    const chosen = o.vtxoIds ? freeCoins(arkStateNow()).filter((v) => o.vtxoIds.includes(v.id)) : null;
+    const spendable = chosen ? chosen.reduce((n, v) => n + v.amountSat, 0) : (arkBalance()?.spendableSat || 0);
     if (o.quoteFor !== o.address) {
       o.quote = null; o.quoteDone = false; o.quoteFor = o.address;
       let ok = false; try { addrScript(o.address); ok = true; } catch {}
@@ -3160,10 +3171,11 @@ export function arkFeature(ctx) {
         fee: fmtSats(q.totalSat), chain: fmtSats(q.chainSat), service: fmtSats(q.serviceSat), min: fmtSats(q.minSat),
       })) : !o.quoteDone ? h('div', { class: 'small faint' }, t('arkOffboardQuoting')) : null,
       tooSmall ? h('div', { class: 'notice' }, t('arkOffboardBelowMin', { n: fmtSats(spendable), min: fmtSats(q.minSat) })) : null,
-      h('div', { class: 'input-group' },
-        h('input', { type: 'number', min: '1', placeholder: String(spendable), value: o.amount,
-          onInput: (e) => { o.amount = e.target.value; } }),
-        h('button', { type: 'button', onClick: () => { o.amount = String(spendable); render(); } }, t('max'))),
+      chosen ? h('div', { class: 'small ark-coop-chosen' }, chosen.length === 1 ? t('arkCoopSelectedAmtOne', { amount: fmtSats(spendable) + ' sats' }) : t('arkCoopSelectedAmt', { n: chosen.length, amount: fmtSats(spendable) + ' sats' }))
+        : h('div', { class: 'input-group' },
+          h('input', { type: 'number', min: '1', placeholder: String(spendable), value: o.amount,
+            onInput: (e) => { o.amount = e.target.value; } }),
+          h('button', { type: 'button', onClick: () => { o.amount = String(spendable); render(); } }, t('max'))),
       ui.arkError ? h('div', { class: 'notice err' }, ui.arkError) : null,
       h('div', { class: 'row gap6' },
         h('button', { class: 'btn-ghost grow', onClick: () => {
@@ -3173,7 +3185,7 @@ export function arkFeature(ctx) {
         ui.arkBusy === 'offboard'
           ? h('button', { class: 'btn-primary grow', disabled: true }, h('span', { class: 'spinner sm' }))
           : h('button', { class: 'btn-primary grow', disabled: tooSmall, onClick: () => {
-              const amount = String(o.amount ?? '').trim();
+              const amount = chosen ? String(spendable) : String(o.amount ?? '').trim();
               const sats = amount ? Number(amount) : spendable;
               if (!Number.isSafeInteger(sats) || sats <= 0 || sats > spendable) { ui.arkError = t('enterValidAmtForN', { n: 1 }); render(); return; }
               try { addrScript(o.address); } catch { ui.arkError = t('arkOffboardBadAddress'); render(); return; }
@@ -3182,7 +3194,7 @@ export function arkFeature(ctx) {
                 ui.arkCoopFailed = false;
                 ui.arkError = t('arkOffboardAmtBelowMin', { min: fmtSats(q.minSat), fee: fmtSats(q.totalSat) }); render(); return;
               }
-              doArkOffboard(sats >= spendable ? 0 : sats, o.address);
+              doArkOffboard(sats >= spendable ? 0 : sats, o.address, chosen ? o.vtxoIds : undefined);
             } }, t('arkSendBtn'))),
       // This send IS the cooperative exit. The trustless fallback only
       // appears when cooperation actually failed (not when the amount was
@@ -3218,7 +3230,9 @@ export function arkFeature(ctx) {
       })());
   }
 
-  async function doArkOffboard(amountSat, destAddress = null) {
+  // vtxoIds: exactly these coins go (the coins page's ticked subset);
+  // otherwise an amount is split off the balance, or everything goes.
+  async function doArkOffboard(amountSat, destAddress = null, vtxoIds = undefined) {
     ui.arkBusy = 'offboard'; ui.arkError = ''; ui.arkCoopFailed = false; render();
     try {
       const address = destAddress || wallet.freshReceive().address;
@@ -3226,8 +3240,8 @@ export function arkFeature(ctx) {
       const mgr = await connectArk();
       const spendables = () => freeCoins(mgr.state);
       const total = spendables().reduce((n, v) => n + v.amountSat, 0);
-      let ids; // undefined = all spendable vtxos
-      if (amountSat && amountSat < total) {
+      let ids = vtxoIds; // undefined = all spendable vtxos
+      if (!ids && amountSat && amountSat < total) {
         let target = spendables().find((v) => v.amountSat === amountSat);
         if (!target) {
           const before = new Set(spendables().map((v) => v.id));
diff --git a/src/i18n.js b/src/i18n.js
index e9e298f..71ad321 100644
--- a/src/i18n.js
+++ b/src/i18n.js
@@ -778,6 +778,10 @@ const STR = {
     arkFeeService: 'Service fee',
     arkCoinsExpired: 'expired',
     arkCoinsHeld: 'held by Coinos',
+    arkCoopSelected: 'Only the {n} coins ticked above will move.',
+    arkCoopSelectedOne: 'Only the coin ticked above will move.',
+    arkCoopSelectedAmt: '{n} selected coins · {amount}',
+    arkCoopSelectedAmtOne: '1 selected coin · {amount}',
     arkCustodyTitle: 'Custody',
     arkCustodyDesc: 'Each coin expires about {days} days after it was made. Until then you can bring it on-chain yourself, without Coinos. Renewing a coin before it expires keeps that right for another {days} days and costs a small fee. Coinos keeps honoring expired coins, so renewing is a choice:',
     arkCustodyCustodial: 'Allow coins to expire',
diff --git a/tools/ark/cooperative-exit-ui-test.js b/tools/ark/cooperative-exit-ui-test.js
index d8fa0d8..506bca6 100644
--- a/tools/ark/cooperative-exit-ui-test.js
+++ b/tools/ark/cooperative-exit-ui-test.js
@@ -162,6 +162,19 @@ try {
   assert.deepEqual(await page.evaluate(() => coopCalls[1].script), await page.evaluate(() => [...coopApp.wallet.derive(0, 1).script]));
   console.log('✓ Editing the destination and amount offboards only the requested amount to the chosen on-chain address');
 
+  // ticking a subset on Manage: exactly those coins go, no split, the amount is theirs and not a field
+  await manage();
+  await page.evaluate(() => { coopApp.ui.arkCoinsSel = new Set(['coin-b']); coopApp.render(); });
+  assert.match(await page.evaluate(() => [...document.querySelectorAll('.card')].find((c) => c.querySelector('h4')?.textContent === 'Co-operative exit').innerText), /Only the coin ticked above will move[\s\S]*Move 8,000 sats to Savings/);
+  await coopButton();
+  await page.waitForSelector('.ark-coop-chosen');
+  assert.match(await page.$eval('.ark-coop-chosen', (e) => e.textContent), /1 selected coin · 8,000 sats/);
+  assert.equal(await page.$('input[type="number"]'), null, 'no amount field for chosen coins');
+  await send();
+  await page.waitForFunction(() => coopCalls.length === 3 && !coopApp.ui.arkBusy);
+  assert.deepEqual(await page.evaluate(() => ({ type: coopCalls[2].type, ids: coopCalls[2].ids, address: coopCalls[2].address })), { type: 'offboard', ids: ['coin-b'], address: savings });
+  console.log('✓ Ticking a subset on Manage offboards exactly those coins, without splitting');
+
   await manage(); await coopButton();
   await page.evaluate(() => document.querySelector('.app-nav-button[aria-label="Wallet"]').click());
   assert.equal(await page.evaluate(() => coopApp.ui.arkOffboardSend), null);