fix(touch): harden long-press for iOS (#199)

Long-press opens the message action sheet (#166), but on iOS the system
takes a long-press for itself: the link/image callout or the text-selection
loupe races the 450 ms press. Message rows on touch screens now carry
data-touch-actions (no -webkit-touch-callout), and the pressed row carries
data-pressing from touch-down until the finger lifts, which turns text
selection off for that moment only. Copy Text stays in the sheet.

Refs #199

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5

src/app/features/room/message/styles.css.ts

@@ -1,4 +1,4 @@
-import { style } from '@vanilla-extract/css';
+import { globalStyle, style } from '@vanilla-extract/css';
 import { DefaultReset, FocusOutline, color, config, toRem } from 'folds';
 
 export const MessageBase = style({
@@ -77,3 +77,14 @@ export const ReactionsMore = style([
 export const ReactionsTooltipText = style({
   wordBreak: 'break-word',
 });
+
+// [Gitea #199] Long-press opens the message action sheet on touch screens. On
+// iOS a long-press otherwise belongs to the system: a link/image callout, or
+// the text-selection loupe, both of which race (and win against) the 450 ms
+// press. No callout on message rows, and no selection while a finger is
+// down; copying text is in the sheet.
+globalStyle('[data-touch-actions]', { WebkitTouchCallout: 'none' });
+globalStyle('[data-touch-actions][data-pressing], [data-touch-actions][data-pressing] *', {
+  userSelect: 'none',
+  WebkitUserSelect: 'none',
+});

src/app/hooks/useLongPress.ts

@@ -17,22 +17,37 @@ export function useLongPress(onLongPress: (x: number, y: number) => void) {
   const timer = useRef<number | undefined>(undefined);
   const start = useRef<{ x: number; y: number } | null>(null);
   const fired = useRef(false);
+  // [Gitea #199] The element being pressed carries `data-pressing` (set on the
+  // DOM directly, no re-render) so iOS can't start a text selection under
+  // the finger; see `[data-touch-actions]` in room/message/styles.css.ts.
+  const pressed = useRef<HTMLElement | null>(null);
 
-  const clear = useCallback(() => {
+  const stopTimer = useCallback(() => {
     if (timer.current !== undefined) window.clearTimeout(timer.current);
     timer.current = undefined;
     start.current = null;
   }, []);
 
+  // The finger is up (or the gesture was cancelled): only now drop
+  // `data-pressing`, so the system selection can't start under a finger that
+  // is still down after the sheet opened.
+  const clear = useCallback(() => {
+    stopTimer();
+    pressed.current?.removeAttribute('data-pressing');
+    pressed.current = null;
+  }, [stopTimer]);
+
   const onTouchStart = useCallback(
     (evt: React.TouchEvent) => {
       if (!coarse || evt.touches.length !== 1) return;
       const t = evt.touches[0];
       start.current = { x: t.clientX, y: t.clientY };
       fired.current = false;
+      pressed.current = evt.currentTarget as HTMLElement;
+      pressed.current.setAttribute('data-pressing', '');
       timer.current = window.setTimeout(() => {
         const s = start.current;
-        clear();
+        stopTimer();
         if (!s) return;
         fired.current = true;
         window.setTimeout(() => {
@@ -41,7 +56,7 @@ export function useLongPress(onLongPress: (x: number, y: number) => void) {
         onLongPress(s.x, s.y);
       }, LONG_PRESS_MS);
     },
-    [coarse, clear, onLongPress],
+    [coarse, stopTimer, onLongPress],
   );
 
   const onTouchMove = useCallback(
@@ -72,7 +87,16 @@ export function useLongPress(onLongPress: (x: number, y: number) => void) {
 
   return {
     coarse,
-    handlers: coarse ? { onTouchStart, onTouchMove, onTouchEnd, onTouchCancel: clear } : {},
+    handlers: coarse
+      ? {
+          // [Gitea #199] Marks the element for the iOS hardening CSS.
+          'data-touch-actions': '',
+          onTouchStart,
+          onTouchMove,
+          onTouchEnd,
+          onTouchCancel: clear,
+        }
+      : {},
     /** True for ~1 s after a long-press fired (drop the Android contextmenu echo). */
     suppressContextMenu: fired,
   };