fix: Meta double-paste + cancel on timeout/focus switch

extension/background.js

@@ -88,6 +88,27 @@ function waitTabComplete(tabId, timeoutMs = 25000) {
   });
 }
 
+/**
+ * True when the existing tab is already on the target AI app.
+ * Do NOT re-navigate merely because query/hash/conversation id differ — that
+ * forced cold=1 on every Meta/Gemini hotkey and re-hydrated the composer.
+ *
+ * Rules:
+ * - origin must match
+ * - want path "/" (meta.ai/, chatgpt.com/): any path on that origin is fine
+ * - otherwise accept exact path or prefix (gemini /app → /app/xyz)
+ */
+function isAlreadyOnApp(u, want) {
+  if (u.origin !== want.origin) return false;
+  let wantPath = want.pathname || '/';
+  if (wantPath.length > 1 && wantPath.endsWith('/')) wantPath = wantPath.slice(0, -1);
+  if (wantPath === '/' || wantPath === '') return true;
+  const path = u.pathname || '/';
+  if (path === wantPath) return true;
+  const prefix = wantPath.endsWith('/') ? wantPath : wantPath + '/';
+  return path.startsWith(prefix);
+}
+
 /**
  * Focus or open a tab for url.
  * Returns { tabId, cold } where cold=true if we created a tab or navigated.
@@ -110,7 +131,7 @@ async function ensureTab(url) {
         }
       }
       let cold = false;
-      if (u.pathname !== want.pathname || u.search !== want.search || u.hash !== want.hash) {
+      if (!isAlreadyOnApp(u, want)) {
         await chrome.tabs.update(t.id, { url });
         cold = true;
         await waitTabComplete(t.id);
@@ -125,9 +146,12 @@ async function ensureTab(url) {
   return { tabId: created.id, cold: true };
 }
 
-async function sendToTab(tabId, message, attempts = 16) {
+async function sendToTab(tabId, message, attempts = 16, deadlineMs = 0) {
   let lastErr = 'no response';
   for (let i = 0; i < attempts; ++i) {
+    if (deadlineMs && Date.now() >= deadlineMs) {
+      return { ok: false, error: 'timeout waiting for content script' };
+    }
     try {
       const resp = await chrome.tabs.sendMessage(tabId, message);
       if (resp) return resp;
@@ -145,11 +169,46 @@ async function sendToTab(tabId, message, attempts = 16) {
         }
       }
     }
-    await sleep(300);
+    const slice = deadlineMs ? Math.min(300, Math.max(50, deadlineMs - Date.now())) : 300;
+    if (slice <= 0) break;
+    await sleep(slice);
   }
   return { ok: false, error: lastErr };
 }
 
+async function tabStillActiveOnOrigin(tabId, wantOrigin, cancelOnFocusSwitch = true) {
+  try {
+    const t = await chrome.tabs.get(tabId);
+    if (!t) return { ok: false, error: 'tab gone' };
+    if (wantOrigin && t.url) {
+      try {
+        if (new URL(t.url).origin !== wantOrigin) {
+          return { ok: false, error: 'tab navigated off AI origin' };
+        }
+      } catch {
+        /* ignore bad url */
+      }
+    }
+    if (!cancelOnFocusSwitch) return { ok: true };
+
+    // Tab.active only means selected in its window — still true if another app has OS focus.
+    if (t.active === false) return { ok: false, error: 'tab inactive / focus switched' };
+    if (t.windowId != null) {
+      try {
+        const w = await chrome.windows.get(t.windowId);
+        if (w && w.focused === false) {
+          return { ok: false, error: 'browser window not focused' };
+        }
+      } catch {
+        /* ignore — some hosts deny windows.get */
+      }
+    }
+    return { ok: true };
+  } catch (e) {
+    return { ok: false, error: String(e) };
+  }
+}
+
 async function onNativeMessage(msg) {
   log('native msg', msg && msg.cmd, msg && msg.id);
   if (!msg || typeof msg !== 'object') return;
@@ -163,24 +222,62 @@ async function onNativeMessage(msg) {
     if (msg.cmd === 'prepareAndPaste') {
       const url = String(msg.url || '');
       const text = String(msg.text || '');
-      const timeoutMs = Math.max(1000, Number(msg.timeoutMs) || 15000);
+      // Hard cap 10s for form wait — matches product rule: cancel rather than surprise-paste.
+      const timeoutMs = Math.min(10000, Math.max(1000, Number(msg.timeoutMs) || 10000));
+      // Default true; tray can pass cancelOnFocusSwitch:false to disable focus leave cancel.
+      const cancelOnFocusSwitch = msg.cancelOnFocusSwitch !== false;
       if (!url) {
         reply(msg, { ok: false, error: 'missing url' });
         return;
       }
+      let wantOrigin = '';
+      try {
+        wantOrigin = new URL(url).origin;
+      } catch {
+        /* ignore */
+      }
+      const deadline = Date.now() + timeoutMs + 1500;
       const { tabId, cold } = await ensureTab(url);
       // Cold open / navigate: SPA shell is not ready at status=complete.
       if (cold) {
         await sleep(900);
       } else {
         await sleep(250);
       }
-      const resp = await sendToTab(tabId, {
-        cmd: 'waitAndPaste',
-        text,
-        timeoutMs,
-        cold: !!cold,
-      });
+      const focusCheck = await tabStillActiveOnOrigin(tabId, wantOrigin, cancelOnFocusSwitch);
+      if (!focusCheck.ok) {
+        reply(msg, {
+          ok: false,
+          error: focusCheck.error || 'tab inactive / focus switched',
+          cold: !!cold,
+        });
+        return;
+      }
+      const remain = Math.max(500, deadline - Date.now());
+      const resp = await sendToTab(
+        tabId,
+        {
+          cmd: 'waitAndPaste',
+          text,
+          timeoutMs: Math.min(timeoutMs, remain),
+          cold: !!cold,
+          wantOrigin,
+          cancelOnFocusSwitch,
+        },
+        16,
+        deadline,
+      );
+      // Final guard: if user left while content script worked, still report cancel.
+      const after = await tabStillActiveOnOrigin(tabId, wantOrigin, cancelOnFocusSwitch);
+      if (resp && resp.ok && !after.ok) {
+        reply(msg, {
+          ok: false,
+          error: after.error || 'tab inactive after paste',
+          detail: resp.detail,
+          cold: !!cold,
+        });
+        return;
+      }
       reply(msg, {
         ok: !!(resp && resp.ok),
         detail: (resp && (resp.detail || resp.error)) || '',
@@ -193,11 +290,36 @@ async function onNativeMessage(msg) {
 
     if (msg.cmd === 'prepare') {
       const url = String(msg.url || '');
-      const timeoutMs = Math.max(1000, Number(msg.timeoutMs) || 15000);
+      const timeoutMs = Math.min(10000, Math.max(1000, Number(msg.timeoutMs) || 10000));
+      const cancelOnFocusSwitch = msg.cancelOnFocusSwitch !== false;
+      let wantOrigin = '';
+      try {
+        wantOrigin = new URL(url).origin;
+      } catch {
+        /* ignore */
+      }
+      const deadline = Date.now() + timeoutMs + 1500;
       const { tabId, cold } = await ensureTab(url);
       if (cold) await sleep(900);
       else await sleep(250);
-      const resp = await sendToTab(tabId, { cmd: 'findComposer', timeoutMs, cold: !!cold });
+      const focusCheck = await tabStillActiveOnOrigin(tabId, wantOrigin, cancelOnFocusSwitch);
+      if (!focusCheck.ok) {
+        reply(msg, { ok: false, error: focusCheck.error || 'tab inactive', cold: !!cold });
+        return;
+      }
+      const remain = Math.max(500, deadline - Date.now());
+      const resp = await sendToTab(
+        tabId,
+        {
+          cmd: 'findComposer',
+          timeoutMs: Math.min(timeoutMs, remain),
+          cold: !!cold,
+          wantOrigin,
+          cancelOnFocusSwitch,
+        },
+        16,
+        deadline,
+      );
       reply(msg, {
         ok: !!(resp && resp.ok),
         detail: (resp && resp.detail) || '',