[Init] Initial commit - NetMesh terminal manager

components/terminal/autocomplete/ghostTextConsistency.ts

@@ -0,0 +1,42 @@
+/**
+ * Fail-safe consistency check for inline (ghost-text) suggestions.
+ *
+ * Ghost text renders `suggestion.substring(trackedInput.length)` after the
+ * cursor, where `trackedInput` is what the client thinks the user has typed.
+ * On hosts with non-standard echo (hardware bastion hosts / network OS such as
+ * `ecOS#`, issue #1013, previously #756 / #906) that tracked value drifts out
+ * of sync with what is actually on the terminal line, and the ghost ends up
+ * painted over characters the user already typed (`int` + ghost `terface` →
+ * `intterface`).
+ *
+ * This detects the one direction that produces visible corruption: the real
+ * line being AHEAD of the tracked input (it contains the tracked input
+ * followed by more, untracked characters). SSH echo latency is the opposite
+ * case — the line is a prefix-behind of the tracked input — and is
+ * intentionally NOT flagged, so the ghost stays responsive on slow links.
+ *
+ * Returns true when the caller should hide the ghost.
+ */
+export function lineHasUntrackedTrailingInput(
+  trackedInput: string,
+  lineBeforeCursor: string,
+): boolean {
+  // Single chars match too loosely to judge reliably; let them through.
+  if (trackedInput.length < 2) return false;
+  // Column↔string mapping is only unambiguous for narrow (ASCII) input, so the
+  // existing wide-char (CJK / emoji) handling is left untouched.
+  if (!/^[\x20-\x7e]+$/.test(trackedInput)) return false;
+
+  // Use the last occurrence so a prompt or command that repeats the same token
+  // earlier on the line doesn't shadow the freshly-typed input.
+  const idx = lineBeforeCursor.lastIndexOf(trackedInput);
+  if (idx < 0) {
+    // Tracked input isn't on screen yet — the echo is still catching up
+    // (latency). Keep the ghost; reality being behind never corrupts.
+    return false;
+  }
+
+  // Non-whitespace characters between the tracked input and the cursor mean the
+  // device echoed input we never tracked → the ghost would overlap real text.
+  return lineBeforeCursor.slice(idx + trackedInput.length).trimEnd().length > 0;
+}