Support sharing links to individual messages (#177)

apps/web/src/app/(authenticated)/usage/Messages.tsx

@@ -1,5 +1,7 @@
-import { useMemo, useEffect } from 'react';
+import { useMemo, useEffect, useState } from 'react';
 import ReactMarkdown from 'react-markdown';
+import { Link2 } from 'lucide-react';
+import { toast } from 'sonner';
 
 import type { Message } from '@/actions/analytics';
 import { cn } from '@/lib/utils';
@@ -14,6 +16,8 @@ const PlainTextLink = ({ children }: { children?: React.ReactNode }) => {
 
 type MessagesProps = {
   messages: Message[];
+  enableMessageLinks?: boolean;
+  shareToken?: string;
 };
 
 type SuggestionItem = string | { answer: string };
@@ -40,7 +44,13 @@ const parseQuestionData = (text: string): QuestionData | null => {
   return null;
 };
 
-export const Messages = ({ messages }: MessagesProps) => {
+export const Messages = ({
+  messages,
+  enableMessageLinks = false,
+}: MessagesProps) => {
+  const [hoveredMessageId, setHoveredMessageId] = useState<string | null>(null);
+  const [clickedMessageId, setClickedMessageId] = useState<string | null>(null);
+
   const { containerRef, scrollToBottom, autoScrollToBottom, userHasScrolled } =
     useAutoScroll<HTMLDivElement>({
       enabled: true,
@@ -69,6 +79,59 @@ export const Messages = ({ messages }: MessagesProps) => {
     );
   }, [messages]);
 
+  // Handle anchor link clicks
+  const handleAnchorClick = (messageId: string) => {
+    // Add click animation
+    setClickedMessageId(messageId);
+    setTimeout(() => setClickedMessageId(null), 200);
+
+    const url = new URL(window.location.href);
+    url.hash = `#${messageId}`;
+
+    // Update URL without reload
+    window.history.replaceState(null, '', url.toString());
+
+    // Copy to clipboard with enhanced feedback
+    navigator.clipboard
+      .writeText(url.toString())
+      .then(() => {
+        toast.success('Message link copied to clipboard!', {
+          description: 'Share this link to highlight this specific message',
+          duration: 3000,
+        });
+      })
+      .catch(() => {
+        toast.error('Failed to copy link', {
+          description: 'Please try again or copy the URL manually',
+          duration: 4000,
+        });
+      });
+  };
+
+  // Handle URL hash on mount and highlight message
+  useEffect(() => {
+    if (enableMessageLinks && window.location.hash) {
+      const messageId = window.location.hash.substring(1);
+      const element = document.getElementById(messageId);
+      if (element) {
+        // Small delay to ensure the component is fully rendered
+        // Add simple highlight effect immediately
+        element.style.transition = 'background-color 0.3s ease-in-out';
+        element.style.backgroundColor = 'rgba(59, 130, 246, 0.1)';
+
+        // Fade out the highlight after 2 seconds
+        setTimeout(() => {
+          element.style.backgroundColor = '';
+        }, 2000);
+
+        // Delay scroll to allow things to load
+        setTimeout(() => {
+          element.scrollIntoView({ behavior: 'smooth', block: 'start' });
+        }, 1000);
+      }
+    }
+  }, [enableMessageLinks]);
+
   // Auto-scroll when new messages arrive or content changes (only if user is at bottom)
   useEffect(() => {
     autoScrollToBottom();
@@ -92,13 +155,23 @@ export const Messages = ({ messages }: MessagesProps) => {
           const questionData =
             isQuestion && message.text ? parseQuestionData(message.text) : null;
 
+          const messageId = `message-${message.id}`;
+
           return (
             <div
               key={message.id}
+              id={messageId}
               className={cn(
-                'flex flex-col gap-3 rounded-lg p-4',
+                'flex flex-col gap-3 rounded-lg p-4 relative transition-all duration-200',
                 message.role === 'user' ? 'bg-primary/10' : 'bg-secondary/10',
+                enableMessageLinks && 'hover:shadow-sm hover:bg-opacity-80',
               )}
+              onMouseEnter={() =>
+                enableMessageLinks && setHoveredMessageId(messageId)
+              }
+              onMouseLeave={() =>
+                enableMessageLinks && setHoveredMessageId(null)
+              }
             >
               <div className="flex flex-row items-center justify-between gap-2 text-xs font-medium text-muted-foreground">
                 <div className="flex items-center gap-2">
@@ -106,11 +179,32 @@ export const Messages = ({ messages }: MessagesProps) => {
                   <div>&middot;</div>
                   <div>{message.timestamp}</div>
                 </div>
-                {message.mode && (
-                  <div className="px-2 py-1 bg-muted rounded text-xs font-medium">
-                    {message.mode}
-                  </div>
-                )}
+                <div className="flex items-center gap-2">
+                  {/* Anchor Link Button */}
+                  {enableMessageLinks && hoveredMessageId === messageId && (
+                    <button
+                      onClick={() => handleAnchorClick(messageId)}
+                      className={cn(
+                        'p-1 rounded hover:bg-muted transition-colors duration-200 cursor-pointer',
+                        clickedMessageId === messageId && 'bg-primary/10',
+                      )}
+                      title="Copy link to this message"
+                      type="button"
+                    >
+                      <Link2
+                        className={cn(
+                          'h-3 w-3 text-muted-foreground hover:text-primary transition-colors duration-200',
+                          clickedMessageId === messageId && 'text-primary',
+                        )}
+                      />
+                    </button>
+                  )}
+                  {message.mode && (
+                    <div className="px-2 py-1 bg-muted rounded text-xs font-medium">
+                      {message.mode}
+                    </div>
+                  )}
+                </div>
               </div>
 
               {isQuestion && questionData ? (

apps/web/src/components/task-sharing/SharedTaskView.tsx

@@ -51,6 +51,8 @@ export const SharedTaskView = ({
       sharedBy={sharedBy}
       sharedAt={sharedAt}
       showSharedInfo={true}
+      enableMessageLinks={true}
+      shareToken={shareToken}
     />
   );
 };

apps/web/src/components/task-sharing/TaskDetails.tsx

@@ -22,6 +22,8 @@ type TaskDetailsProps = {
   sharedAt?: Date;
   showSharedInfo?: boolean;
   headerActions?: React.ReactNode;
+  enableMessageLinks?: boolean;
+  shareToken?: string;
 };
 
 export const TaskDetails = ({
@@ -31,6 +33,8 @@ export const TaskDetails = ({
   sharedAt,
   showSharedInfo = false,
   headerActions,
+  enableMessageLinks = false,
+  shareToken,
 }: TaskDetailsProps) => {
   const taskTitle = task.title || generateFallbackTitle(task);
 
@@ -152,7 +156,11 @@ export const TaskDetails = ({
             <CardTitle>Conversation</CardTitle>
           </CardHeader>
           <CardContent>
-            <Messages messages={messages} />
+            <Messages
+              messages={messages}
+              enableMessageLinks={enableMessageLinks}
+              shareToken={shareToken}
+            />
           </CardContent>
         </Card>
       ) : (