Merge pull request #205 from simoleo89/fix/friendbar-overflow-autofit

fix(friendbar): auto-fit visible friend count so the bar stops clipping

src/components/friends/views/friends-bar/FriendsBarView.tsx

@@ -1,11 +1,23 @@
-import { FC, useRef, useState } from 'react';
+import { FC, useLayoutEffect, useRef, useState } from 'react';
 import { FaChevronLeft, FaChevronRight } from 'react-icons/fa';
 import { LocalizeText, MessengerFriend } from '../../../../api';
 import { FriendBarItemView } from './FriendBarItemView';
 import { motion, AnimatePresence, Variants } from 'framer-motion';
 
+// Hard cap on simultaneously-shown friend chips. The effective count is
+// reduced below this when the bar would otherwise overflow its (clipped)
+// slot in the toolbar — see the width measurement below.
 const MAX_DISPLAY_COUNT = 3;
 
+// Layout constants mirrored from FriendBarItemView / the flex gaps here, used
+// to compute how many friend chips fit in the available width. A "slot" is one
+// w-[132px] button plus the gap-[6px] that precedes it.
+const ITEM_SLOT = 138; // 132px chip + 6px gap (friend chip and search chip)
+const ARROWS_WIDTH = 52; // two w-[20px] arrows, each + 6px gap
+const REQUEST_SLOT = 120; // requests chip (only present when requestsCount > 0)
+const BASE_PAD = 8; // container px-[2px] + a little slack
+const RIGHT_SAFE = 24; // right inset (right-0/right-3) + pr-3 safety margin
+
 // Mirrored from Toolbar to keep physics identical
 const containerVariants: Variants = {
     hidden: {},
@@ -23,9 +35,55 @@ export const FriendBarView: FC<{ onlineFriends: MessengerFriend[]; requestsCount
 {
     const { onlineFriends = [], requestsCount = 0 } = props;
     const [ indexOffset, setIndexOffset ] = useState(0);
+    const [ maxVisible, setMaxVisible ] = useState(MAX_DISPLAY_COUNT);
     const elementRef = useRef<HTMLDivElement>(null);
-    const hasScrollableFriends = (onlineFriends.length > MAX_DISPLAY_COUNT);
-    const visibleFriends = onlineFriends.slice(indexOffset, (indexOffset + MAX_DISPLAY_COUNT));
+
+    // Auto-fit the visible friend count to the room actually available between
+    // the bar's left edge and the right side of the viewport. The bar lives in
+    // a `overflow-x: clip` toolbar slot, so anything that doesn't fit would be
+    // silently cut off (the scroll arrow / search button disappear). The bar's
+    // left edge is stable (it sits after fixed-width toolbar icons), so growing
+    // or shrinking the chip count never moves it — no measurement feedback loop.
+    useLayoutEffect(() =>
+    {
+        const element = elementRef.current;
+
+        if(!element) return;
+
+        const measure = () =>
+        {
+            const left = element.getBoundingClientRect().left;
+            const available = window.innerWidth - left - RIGHT_SAFE;
+            const fixed = ARROWS_WIDTH + ITEM_SLOT /* search chip */ + BASE_PAD + ((requestsCount > 0) ? REQUEST_SLOT : 0);
+            const fit = Math.floor((available - fixed) / ITEM_SLOT);
+            const next = Math.max(1, Math.min(MAX_DISPLAY_COUNT, fit));
+
+            setMaxVisible(prev => ((prev === next) ? prev : next));
+        };
+
+        measure();
+
+        const observer = new ResizeObserver(measure);
+
+        observer.observe(document.documentElement);
+        window.addEventListener('resize', measure);
+
+        return () =>
+        {
+            observer.disconnect();
+            window.removeEventListener('resize', measure);
+        };
+    }, [ requestsCount, onlineFriends.length ]);
+
+    // `safeOffset` is the offset clamped to the current list/fit. Every read
+    // below uses it, so a stale `indexOffset` (after the list shrinks or the fit
+    // grows) renders correctly and self-corrects on the next arrow click — no
+    // write-back effect needed.
+    const maxOffset = Math.max(0, (onlineFriends.length - maxVisible));
+    const safeOffset = Math.min(indexOffset, maxOffset);
+    const canScrollLeft = (safeOffset > 0);
+    const canScrollRight = (safeOffset < maxOffset);
+    const visibleFriends = onlineFriends.slice(safeOffset, (safeOffset + maxVisible));
 
     return (
         <motion.div
@@ -44,10 +102,10 @@ export const FriendBarView: FC<{ onlineFriends: MessengerFriend[]; requestsCount
                 </motion.div> }
             <motion.div variants={itemVariants}>
                 <div
-                    className={ `flex h-[34px] w-[20px] items-center justify-center text-white/80 transition-all ${ (!hasScrollableFriends || (indexOffset <= 0)) ? 'opacity-30 cursor-not-allowed' : 'cursor-pointer hover:text-white active:scale-95' }` }
+                    className={ `flex h-[34px] w-[20px] items-center justify-center text-white/80 transition-all ${ !canScrollLeft ? 'opacity-30 cursor-not-allowed' : 'cursor-pointer hover:text-white active:scale-95' }` }
                     onClick={ () =>
                     {
-                        if(indexOffset > 0) setIndexOffset(indexOffset - 1);
+                        if(canScrollLeft) setIndexOffset(safeOffset - 1);
                     } }
                 >
                     <FaChevronLeft className="text-white/70 text-sm drop-shadow-[1px_1px_0_#000]" />
@@ -94,10 +152,10 @@ export const FriendBarView: FC<{ onlineFriends: MessengerFriend[]; requestsCount
 
             <motion.div variants={itemVariants}>
                 <div
-                    className={ `flex h-[34px] w-[20px] items-center justify-center text-white/80 transition-all ${ (!hasScrollableFriends || !((onlineFriends.length > MAX_DISPLAY_COUNT) && ((indexOffset + MAX_DISPLAY_COUNT) <= (onlineFriends.length - 1)))) ? 'opacity-30 cursor-not-allowed' : 'cursor-pointer hover:text-white active:scale-95' }` }
+                    className={ `flex h-[34px] w-[20px] items-center justify-center text-white/80 transition-all ${ !canScrollRight ? 'opacity-30 cursor-not-allowed' : 'cursor-pointer hover:text-white active:scale-95' }` }
                     onClick={ () =>
                     {
-                        if((onlineFriends.length > MAX_DISPLAY_COUNT) && ((indexOffset + MAX_DISPLAY_COUNT) <= (onlineFriends.length - 1))) setIndexOffset(indexOffset + 1);
+                        if(canScrollRight) setIndexOffset(safeOffset + 1);
                     } }
                 >
                     <FaChevronRight className="text-white/70 text-sm drop-shadow-[1px_1px_0_#000]" />