[Init] Initial commit - NetMesh terminal manager

components/terminal/copyOnSelect.ts

@@ -0,0 +1,168 @@
+/**
+ * Copy-on-select policy for the xterm selection overlay.
+ *
+ * SearchAddon (and other programmatic paths) call terminal.select() to mark
+ * the active match. Those selection-change events must not write the
+ * clipboard — otherwise a later user selection is overwritten by the search
+ * term after a resize/write revival (issue #3007).
+ */
+
+export const COPY_ON_SELECT_USER_GESTURE_RELEASE_MS = 80;
+
+export type CopyOnSelectUserGestureTracker = {
+  mark: () => void;
+  release: () => void;
+  /** Mark then release — one-shot gestures such as a late contextmenu. */
+  pulse: () => void;
+  isActive: () => boolean;
+  dispose: () => void;
+};
+
+export const createCopyOnSelectUserGestureTracker = ({
+  releaseDelayMs = COPY_ON_SELECT_USER_GESTURE_RELEASE_MS,
+  setTimeoutFn = setTimeout,
+  clearTimeoutFn = clearTimeout,
+}: {
+  releaseDelayMs?: number;
+  setTimeoutFn?: typeof setTimeout;
+  clearTimeoutFn?: typeof clearTimeout;
+} = {}): CopyOnSelectUserGestureTracker => {
+  let active = false;
+  let releaseTimer: ReturnType<typeof setTimeout> | null = null;
+
+  const clearReleaseTimer = () => {
+    if (releaseTimer === null) return;
+    clearTimeoutFn(releaseTimer);
+    releaseTimer = null;
+  };
+
+  const mark = () => {
+    clearReleaseTimer();
+    active = true;
+  };
+
+  const release = () => {
+    clearReleaseTimer();
+    releaseTimer = setTimeoutFn(() => {
+      releaseTimer = null;
+      active = false;
+    }, releaseDelayMs);
+  };
+
+  const pulse = () => {
+    mark();
+    release();
+  };
+
+  const dispose = () => {
+    clearReleaseTimer();
+    active = false;
+  };
+
+  return {
+    mark,
+    release,
+    pulse,
+    isActive: () => active,
+    dispose,
+  };
+};
+
+const CAPTURE = { capture: true } as const;
+
+const eventIsInsideTerminal = (
+  event: Event,
+  el: EventTarget,
+): boolean => {
+  const target = event.target;
+  if (!target) return false;
+  if (target === el) return true;
+  const host = el as { contains?: (node: EventTarget) => boolean };
+  return typeof host.contains === "function" && host.contains(target);
+};
+
+export const subscribeCopyOnSelectUserGesture = (
+  term: { element?: EventTarget | null } | null | undefined,
+  tracker: Pick<CopyOnSelectUserGestureTracker, "mark" | "release" | "pulse">,
+  root: Pick<EventTarget, "addEventListener" | "removeEventListener"> | null = (
+    typeof document === "undefined" ? null : document
+  ),
+  view: Pick<EventTarget, "addEventListener" | "removeEventListener"> | null = (
+    typeof window === "undefined" ? null : window
+  ),
+): (() => void) => {
+  const el = term?.element;
+  if (!el || !root) return () => {};
+
+  const onPointerDown = (event: Event) => {
+    if (!eventIsInsideTerminal(event, el)) return;
+    tracker.mark();
+  };
+  const onContextMenu = (event: Event) => {
+    if (!eventIsInsideTerminal(event, el)) return;
+    // Capture on the document so we still see right-clicks that
+    // useTerminalEffects intercepts with stopImmediatePropagation
+    // (tmux/vim mouse tracking + select-word). Pulse so a late
+    // contextmenu after mouseup cannot leave the tracker armed.
+    tracker.pulse();
+  };
+  const onPointerUp = () => tracker.release();
+
+  root.addEventListener("mousedown", onPointerDown, CAPTURE);
+  root.addEventListener("touchstart", onPointerDown, CAPTURE);
+  root.addEventListener("contextmenu", onContextMenu, CAPTURE);
+  root.addEventListener("mouseup", onPointerUp);
+  root.addEventListener("touchend", onPointerUp);
+  root.addEventListener("touchcancel", onPointerUp);
+  // Alt-tab / window blur drops the matching mouseup in Electron.
+  view?.addEventListener("blur", onPointerUp);
+
+  return () => {
+    root.removeEventListener("mousedown", onPointerDown, CAPTURE);
+    root.removeEventListener("touchstart", onPointerDown, CAPTURE);
+    root.removeEventListener("contextmenu", onContextMenu, CAPTURE);
+    root.removeEventListener("mouseup", onPointerUp);
+    root.removeEventListener("touchend", onPointerUp);
+    root.removeEventListener("touchcancel", onPointerUp);
+    view?.removeEventListener("blur", onPointerUp);
+  };
+};
+
+const userCommandPulses = new Map<unknown, () => void>();
+
+/** Select All / Select Word from a shortcut or menu — not SearchAddon. */
+export const subscribeCopyOnSelectUserCommand = (
+  key: unknown,
+  pulse: () => void,
+): (() => void) => {
+  userCommandPulses.set(key, pulse);
+  return () => {
+    if (userCommandPulses.get(key) === pulse) {
+      userCommandPulses.delete(key);
+    }
+  };
+};
+
+export const pulseCopyOnSelectUserCommand = (key: unknown): void => {
+  userCommandPulses.get(key)?.();
+};
+
+export const shouldWriteCopyOnSelect = ({
+  allowCopy = true,
+  hasText,
+  copyOnSelect,
+  isRestoringSelection,
+  isUserSelection,
+}: {
+  allowCopy?: boolean;
+  hasText: boolean;
+  copyOnSelect: boolean;
+  isRestoringSelection: boolean;
+  isUserSelection: boolean;
+}): boolean => (
+  allowCopy
+  && hasText
+  && copyOnSelect
+  && !isRestoringSelection
+  && isUserSelection
+);