chore(memo): clarify displayed update time

web/src/components/MemoView/MemoViewContext.tsx

@@ -44,8 +44,11 @@ export const useMemoViewDerived = () => {
   const isInMemoDetailPage = location.pathname.startsWith(`/${memo.name}`) || location.pathname.startsWith("/memos/shares/");
   const commentAmount = computeCommentAmount(memo);
 
-  const displayTimestamp = timeBasis === "update_time" ? memo.updateTime : memo.createTime;
-  const displayTime = displayTimestamp ? timestampDate(displayTimestamp) : undefined;
+  const createTime = memo.createTime ? timestampDate(memo.createTime) : undefined;
+  const updateTime = memo.updateTime ? timestampDate(memo.updateTime) : undefined;
+  const displayTime = timeBasis === "update_time" ? updateTime : createTime;
+  const isDisplayingUpdatedTime =
+    timeBasis === "update_time" && !!createTime && !!updateTime && updateTime.getTime() !== createTime.getTime();
   const relativeTimeFormat: "datetime" | "auto" =
     displayTime && Date.now() - displayTime.getTime() > RELATIVE_TIME_THRESHOLD_MS ? "datetime" : "auto";
 
@@ -54,7 +57,10 @@ export const useMemoViewDerived = () => {
     readonly,
     isInMemoDetailPage,
     commentAmount,
+    createTime,
+    updateTime,
     displayTime,
+    isDisplayingUpdatedTime,
     relativeTimeFormat,
   };
 };

web/src/components/MemoView/components/MemoHeader.tsx

@@ -22,7 +22,7 @@ const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, sh
   const [reactionSelectorOpen, setReactionSelectorOpen] = useState(false);
 
   const { memo, creator, currentUser, parentPage, isArchived, readonly, openEditor } = useMemoViewContext();
-  const { displayTime: memoDisplayTime, relativeTimeFormat } = useMemoViewDerived();
+  const { createTime, updateTime, displayTime: memoDisplayTime, isDisplayingUpdatedTime, relativeTimeFormat } = useMemoViewDerived();
 
   const navigateTo = useNavigateTo();
   const handleGotoMemoDetailPage = useCallback(() => {
@@ -31,19 +31,30 @@ const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, sh
 
   const { unpinMemo } = useMemoActions(memo);
 
-  const displayTime = isArchived ? (
+  const timeValue = isArchived ? (
     memoDisplayTime?.toLocaleString(i18n.language)
   ) : (
-    <relative-time datetime={memoDisplayTime?.toISOString()} lang={i18n.language} format={relativeTimeFormat}></relative-time>
+    <relative-time datetime={memoDisplayTime?.toISOString()} lang={i18n.language} format={relativeTimeFormat} no-title=""></relative-time>
   );
+  const displayTime = isDisplayingUpdatedTime ? (
+    <>
+      {t("common.last-updated-at")} {timeValue}
+    </>
+  ) : (
+    timeValue
+  );
+  const timeTooltip = {
+    createdAt: createTime ? `${t("common.created-at")}: ${createTime.toLocaleString(i18n.language)}` : undefined,
+    updatedAt: updateTime ? `${t("common.last-updated-at")}: ${updateTime.toLocaleString(i18n.language)}` : undefined,
+  };
 
   return (
     <div className="w-full flex flex-row justify-between items-center gap-2">
       <div className="w-auto max-w-[calc(100%-8rem)] grow flex flex-row justify-start items-center">
         {showCreator && creator ? (
-          <CreatorDisplay creator={creator} displayTime={displayTime} onGotoDetail={handleGotoMemoDetailPage} />
+          <CreatorDisplay creator={creator} displayTime={displayTime} timeTooltip={timeTooltip} onGotoDetail={handleGotoMemoDetailPage} />
         ) : (
-          <TimeDisplay displayTime={displayTime} onGotoDetail={handleGotoMemoDetailPage} />
+          <TimeDisplay displayTime={displayTime} timeTooltip={timeTooltip} onGotoDetail={handleGotoMemoDetailPage} />
         )}
       </div>
 
@@ -93,10 +104,11 @@ const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, sh
 interface CreatorDisplayProps {
   creator: User;
   displayTime: React.ReactNode;
+  timeTooltip: TimeTooltipContent;
   onGotoDetail: () => void;
 }
 
-const CreatorDisplay: React.FC<CreatorDisplayProps> = ({ creator, displayTime, onGotoDetail }) => (
+const CreatorDisplay: React.FC<CreatorDisplayProps> = ({ creator, displayTime, timeTooltip, onGotoDetail }) => (
   <div className="w-full flex flex-row justify-start items-center">
     <Link className="w-auto hover:opacity-80 rounded-md transition-colors" to={`/u/${encodeURIComponent(creator.username)}`} viewTransition>
       <UserAvatar className="mr-2 shrink-0" avatarUrl={creator.avatarUrl} />
@@ -109,6 +121,7 @@ const CreatorDisplay: React.FC<CreatorDisplayProps> = ({ creator, displayTime, o
       >
         {creator.displayName || creator.username}
       </Link>
+      <TimeTooltip content={timeTooltip}>
         <button
           type="button"
           className="w-auto -mt-0.5 text-xs leading-tight text-muted-foreground select-none cursor-pointer hover:opacity-80 transition-colors text-left"
@@ -116,23 +129,42 @@ const CreatorDisplay: React.FC<CreatorDisplayProps> = ({ creator, displayTime, o
         >
           {displayTime}
         </button>
+      </TimeTooltip>
     </div>
   </div>
 );
 
+interface TimeTooltipContent {
+  createdAt?: string;
+  updatedAt?: string;
+}
+
+const TimeTooltip = ({ children, content }: { children: React.ReactElement; content: TimeTooltipContent }) => (
+  <Tooltip>
+    <TooltipTrigger asChild>{children}</TooltipTrigger>
+    <TooltipContent align="start" className="flex flex-col items-start gap-0.5 whitespace-nowrap text-left">
+      {content.createdAt && <span>{content.createdAt}</span>}
+      {content.updatedAt && <span>{content.updatedAt}</span>}
+    </TooltipContent>
+  </Tooltip>
+);
+
 interface TimeDisplayProps {
   displayTime: React.ReactNode;
+  timeTooltip: TimeTooltipContent;
   onGotoDetail: () => void;
 }
 
-const TimeDisplay: React.FC<TimeDisplayProps> = ({ displayTime, onGotoDetail }) => (
+const TimeDisplay: React.FC<TimeDisplayProps> = ({ displayTime, timeTooltip, onGotoDetail }) => (
+  <TimeTooltip content={timeTooltip}>
     <button
       type="button"
-    className="w-full text-sm leading-tight text-muted-foreground select-none cursor-pointer hover:text-foreground transition-colors text-left"
+      className="w-auto text-sm leading-tight text-muted-foreground select-none cursor-pointer hover:text-foreground transition-colors text-left"
       onClick={onGotoDetail}
     >
       {displayTime}
     </button>
+  </TimeTooltip>
 );
 
 export default MemoHeader;