Refactor photo embed analytics to post:photoEmbed:* namespace (#10784)

Co-authored-by: Eric Bailey <git@esb.lol>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/view/com/post/Post.tsx

@@ -255,6 +255,7 @@ function PostInner({
                     embed={post.embed}
                     moderation={moderation}
                     viewContext={PostEmbedViewContext.Feed}
+                    post={post}
                   />
                 </View>
               ) : null}

src/view/com/posts/PostFeed.tsx

@@ -13,6 +13,8 @@ import {
 import {
   type AppBskyActorDefs,
   AppBskyEmbedExternal,
+  AppBskyEmbedGallery,
+  AppBskyEmbedImages,
   AppBskyEmbedVideo,
   type AppBskyFeedDefs,
 } from '@atproto/api'
@@ -907,7 +909,9 @@ let PostFeed = ({
 
   const seenActorWithStatusRef = useRef<Set<string>>(new Set())
   const seenPostUrisRef = useRef<Set<string>>(new Set())
-  const seenStandardSiteUrisRef = useRef<Set<string>>(new Set())
+  // Tracks every post we've seen so we can fire per-post events exactly once,
+  // regardless of the post's position within its slice.
+  const seenPerPostUrisRef = useRef<Set<string>>(new Set())
 
   // Helper to calculate position in feed (count only root posts, not interstitials or thread replies)
   const getPostPosition = useNonReactiveCallback(
@@ -940,6 +944,48 @@ let PostFeed = ({
     (item: FeedRow) => {
       feedFeedback.onItemSeen(item)
 
+      // Events that should fire exactly once for every new post, regardless of
+      // its position within a slice or video grid row.
+      const onPostSeen = (post: AppBskyFeedDefs.PostView) => {
+        if (seenPerPostUrisRef.current.has(post.uri)) return
+        seenPerPostUrisRef.current.add(post.uri)
+
+        // Standard site embed view tracking
+        if (
+          AppBskyEmbedExternal.isView(post.embed) &&
+          isStandardSiteEmbed(post.embed.external)
+        ) {
+          ax.metric('embed:standardSite:view', {url: post.embed.external.uri})
+        }
+
+        // Photo embed impression tracking
+        if (
+          AppBskyEmbedImages.isView(post.embed) ||
+          AppBskyEmbedGallery.isView(post.embed)
+        ) {
+          const totalImages = AppBskyEmbedGallery.isView(post.embed)
+            ? post.embed.items.filter(AppBskyEmbedGallery.isViewImage).length
+            : post.embed.images.length
+          const useExpandedLayout = AppBskyEmbedGallery.isView(post.embed)
+            ? totalImages > 4
+            : ax.features.enabled(ax.features.PostGalleryEmbedEnable)
+          const layout =
+            totalImages === 1
+              ? 'single'
+              : useExpandedLayout
+                ? 'carousel'
+                : 'grid'
+
+          ax.metric('post:photoEmbed:impression', {
+            layout,
+            totalImages,
+            postUri: post.uri,
+            postAuthorDid: post.author.did,
+            feedDescriptor: feedFeedback.feedDescriptor || feed,
+          })
+        }
+      }
+
       // Track post:view events
       if (item.type === 'sliceItem') {
         const slice = item.slice
@@ -947,6 +993,8 @@ let PostFeed = ({
         const postItem = slice.items[indexInSlice]
         const post = postItem.post
 
+        onPostSeen(post)
+
         // Only track the root post of each slice (index 0) to avoid double-counting thread items
         if (indexInSlice === 0 && !seenPostUrisRef.current.has(post.uri)) {
           seenPostUrisRef.current.add(post.uri)
@@ -977,16 +1025,6 @@ let PostFeed = ({
             })
           }
         }
-
-        // Standard site embed view tracking
-        if (
-          AppBskyEmbedExternal.isView(post.embed) &&
-          isStandardSiteEmbed(post.embed.external) &&
-          !seenStandardSiteUrisRef.current.has(post.embed.external.uri)
-        ) {
-          seenStandardSiteUrisRef.current.add(post.embed.external.uri)
-          ax.metric('embed:standardSite:view', {url: post.embed.external.uri})
-        }
       } else if (item.type === 'videoGridRow') {
         // Track each video in the grid row
         for (let i = 0; i < item.items.length; i++) {

src/view/com/posts/PostFeedItem.tsx

@@ -429,6 +429,7 @@ let FeedItemInner = ({
               onOpenEmbed={onOpenEmbed}
               post={post}
               additionalPostAlerts={additionalPostAlerts}
+              feedDescriptor={feedDescriptor}
             />
             <PostControls
               post={post}
@@ -460,6 +461,7 @@ let PostContent = ({
   postAuthor,
   onOpenEmbed,
   additionalPostAlerts,
+  feedDescriptor,
 }: {
   moderation: ModerationDecision
   richText: RichTextAPI
@@ -468,6 +470,7 @@ let PostContent = ({
   onOpenEmbed: () => void
   post: AppBskyFeedDefs.PostView
   additionalPostAlerts?: AppModerationCause[]
+  feedDescriptor?: string
 }): React.ReactNode => {
   const [limitLines, setLimitLines] = useState(
     () => countLines(richText.text) >= MAX_POST_LINES,
@@ -528,6 +531,8 @@ let PostContent = ({
             moderation={moderation}
             onOpen={onOpenEmbed}
             viewContext={PostEmbedViewContext.Feed}
+            post={post}
+            feedDescriptor={feedDescriptor}
           />
         </View>
       ) : null}