3 files changed, 363 insertions, 0 deletions
diff --git a/src/state/queries/notifications/feed.ts b/src/state/queries/notifications/feed.ts
new file mode 100644
index 000000000..9d491c3a4
--- /dev/null
+++ b/src/state/queries/notifications/feed.ts
@@ -0,0 +1,212 @@
+import {
+  AppBskyFeedDefs,
+  AppBskyFeedPost,
+  AppBskyFeedRepost,
+  AppBskyFeedLike,
+  AppBskyNotificationListNotifications,
+  BskyAgent,
+} from '@atproto/api'
+import chunk from 'lodash.chunk'
+import {useInfiniteQuery, InfiniteData, QueryKey} from '@tanstack/react-query'
+import {useSession} from '../../session'
+import {useModerationOpts} from '../preferences'
+import {shouldFilterNotif} from './util'
+import {useMutedThreads} from '#/state/muted-threads'
+
+const GROUPABLE_REASONS = ['like', 'repost', 'follow']
+const PAGE_SIZE = 30
+const MS_1HR = 1e3 * 60 * 60
+const MS_2DAY = MS_1HR * 48
+
+type RQPageParam = string | undefined
+type NotificationType =
+  | 'post-like'
+  | 'feedgen-like'
+  | 'repost'
+  | 'mention'
+  | 'reply'
+  | 'quote'
+  | 'follow'
+  | 'unknown'
+
+export function RQKEY() {
+  return ['notification-feed']
+}
+
+export interface FeedNotification {
+  _reactKey: string
+  type: NotificationType
+  notification: AppBskyNotificationListNotifications.Notification
+  additional?: AppBskyNotificationListNotifications.Notification[]
+  subjectUri?: string
+  subject?: AppBskyFeedDefs.PostView
+}
+
+export interface FeedPage {
+  cursor: string | undefined
+  items: FeedNotification[]
+}
+
+export function useNotificationFeedQuery(opts?: {enabled?: boolean}) {
+  const {agent} = useSession()
+  const moderationOpts = useModerationOpts()
+  const threadMutes = useMutedThreads()
+  const enabled = opts?.enabled !== false
+
+  return useInfiniteQuery<
+    FeedPage,
+    Error,
+    InfiniteData<FeedPage>,
+    QueryKey,
+    RQPageParam
+  >({
+    queryKey: RQKEY(),
+    async queryFn({pageParam}: {pageParam: RQPageParam}) {
+      const res = await agent.listNotifications({
+        limit: PAGE_SIZE,
+        cursor: pageParam,
+      })
+
+      // filter out notifs by mod rules
+      const notifs = res.data.notifications.filter(
+        notif => !shouldFilterNotif(notif, moderationOpts),
+      )
+
+      // group notifications which are essentially similar (follows, likes on a post)
+      let notifsGrouped = groupNotifications(notifs)
+
+      // we fetch subjects of notifications (usually posts) now instead of lazily
+      // in the UI to avoid relayouts
+      const subjects = await fetchSubjects(agent, notifsGrouped)
+      for (const notif of notifsGrouped) {
+        if (notif.subjectUri) {
+          notif.subject = subjects.get(notif.subjectUri)
+        }
+      }
+
+      // apply thread muting
+      notifsGrouped = notifsGrouped.filter(
+        notif => !isThreadMuted(notif, threadMutes),
+      )
+
+      return {
+        cursor: res.data.cursor,
+        items: notifsGrouped,
+      }
+    },
+    initialPageParam: undefined,
+    getNextPageParam: lastPage => lastPage.cursor,
+    enabled,
+  })
+}
+
+function groupNotifications(
+  notifs: AppBskyNotificationListNotifications.Notification[],
+): FeedNotification[] {
+  const groupedNotifs: FeedNotification[] = []
+  for (const notif of notifs) {
+    const ts = +new Date(notif.indexedAt)
+    let grouped = false
+    if (GROUPABLE_REASONS.includes(notif.reason)) {
+      for (const groupedNotif of groupedNotifs) {
+        const ts2 = +new Date(groupedNotif.notification.indexedAt)
+        if (
+          Math.abs(ts2 - ts) < MS_2DAY &&
+          notif.reason === groupedNotif.notification.reason &&
+          notif.reasonSubject === groupedNotif.notification.reasonSubject &&
+          notif.author.did !== groupedNotif.notification.author.did
+        ) {
+          groupedNotif.additional = groupedNotif.additional || []
+          groupedNotif.additional.push(notif)
+          grouped = true
+          break
+        }
+      }
+    }
+    if (!grouped) {
+      const type = toKnownType(notif)
+      groupedNotifs.push({
+        _reactKey: `notif-${notif.uri}`,
+        type,
+        notification: notif,
+        subjectUri: getSubjectUri(type, notif),
+      })
+    }
+  }
+  return groupedNotifs
+}
+
+async function fetchSubjects(
+  agent: BskyAgent,
+  groupedNotifs: FeedNotification[],
+): Promise<Map<string, AppBskyFeedDefs.PostView>> {
+  const uris = new Set<string>()
+  for (const notif of groupedNotifs) {
+    if (notif.subjectUri) {
+      uris.add(notif.subjectUri)
+    }
+  }
+  const uriChunks = chunk(Array.from(uris), 25)
+  const postsChunks = await Promise.all(
+    uriChunks.map(uris =>
+      agent.app.bsky.feed.getPosts({uris}).then(res => res.data.posts),
+    ),
+  )
+  const map = new Map<string, AppBskyFeedDefs.PostView>()
+  for (const post of postsChunks.flat()) {
+    if (
+      AppBskyFeedPost.isRecord(post.record) &&
+      AppBskyFeedPost.validateRecord(post.record).success
+    ) {
+      map.set(post.uri, post)
+    }
+  }
+  return map
+}
+
+function toKnownType(
+  notif: AppBskyNotificationListNotifications.Notification,
+): NotificationType {
+  if (notif.reason === 'like') {
+    if (notif.reasonSubject?.includes('feed.generator')) {
+      return 'feedgen-like'
+    }
+    return 'post-like'
+  }
+  if (
+    notif.reason === 'repost' ||
+    notif.reason === 'mention' ||
+    notif.reason === 'reply' ||
+    notif.reason === 'quote' ||
+    notif.reason === 'follow'
+  ) {
+    return notif.reason as NotificationType
+  }
+  return 'unknown'
+}
+
+function getSubjectUri(
+  type: NotificationType,
+  notif: AppBskyNotificationListNotifications.Notification,
+): string | undefined {
+  if (type === 'reply' || type === 'quote' || type === 'mention') {
+    return notif.uri
+  } else if (type === 'post-like' || type === 'repost') {
+    if (
+      AppBskyFeedRepost.isRecord(notif.record) ||
+      AppBskyFeedLike.isRecord(notif.record)
+    ) {
+      return typeof notif.record.subject?.uri === 'string'
+        ? notif.record.subject?.uri
+        : undefined
+    }
+  }
+}
+
+function isThreadMuted(notif: FeedNotification, mutes: string[]): boolean {
+  if (!notif.subject) {
+    return false
+  }
+  const record = notif.subject.record as AppBskyFeedPost.Record // assured in fetchSubjects()
+  return mutes.includes(record.reply?.root.uri || notif.subject.uri)
+}
diff --git a/src/state/queries/notifications/unread.tsx b/src/state/queries/notifications/unread.tsx
new file mode 100644
index 000000000..91aa6f3c2
--- /dev/null
+++ b/src/state/queries/notifications/unread.tsx
@@ -0,0 +1,113 @@
+import React from 'react'
+import * as Notifications from 'expo-notifications'
+import BroadcastChannel from '#/lib/broadcast'
+import {useSession} from '#/state/session'
+import {useModerationOpts} from '../preferences'
+import {shouldFilterNotif} from './util'
+import {isNative} from '#/platform/detection'
+
+const UPDATE_INTERVAL = 30 * 1e3 // 30sec
+
+const broadcast = new BroadcastChannel('NOTIFS_BROADCAST_CHANNEL')
+
+type StateContext = string
+
+interface ApiContext {
+  markAllRead: () => Promise<void>
+  checkUnread: () => Promise<void>
+}
+
+const stateContext = React.createContext<StateContext>('')
+
+const apiContext = React.createContext<ApiContext>({
+  async markAllRead() {},
+  async checkUnread() {},
+})
+
+export function Provider({children}: React.PropsWithChildren<{}>) {
+  const {hasSession, agent} = useSession()
+  const moderationOpts = useModerationOpts()
+
+  const [numUnread, setNumUnread] = React.useState('')
+
+  const checkUnreadRef = React.useRef<(() => Promise<void>) | null>(null)
+  const lastSyncRef = React.useRef<Date>(new Date())
+
+  // periodic sync
+  React.useEffect(() => {
+    if (!hasSession || !checkUnreadRef.current) {
+      return
+    }
+    checkUnreadRef.current() // fire on init
+    const interval = setInterval(checkUnreadRef.current, UPDATE_INTERVAL)
+    return () => clearInterval(interval)
+  }, [hasSession])
+
+  // listen for broadcasts
+  React.useEffect(() => {
+    const listener = ({data}: MessageEvent) => {
+      lastSyncRef.current = new Date()
+      setNumUnread(data.event)
+    }
+    broadcast.addEventListener('message', listener)
+    return () => {
+      broadcast.removeEventListener('message', listener)
+    }
+  }, [setNumUnread])
+
+  // create API
+  const api = React.useMemo<ApiContext>(() => {
+    return {
+      async markAllRead() {
+        // update server
+        await agent.updateSeenNotifications(lastSyncRef.current.toISOString())
+
+        // update & broadcast
+        setNumUnread('')
+        broadcast.postMessage({event: ''})
+      },
+
+      async checkUnread() {
+        // count
+        const res = await agent.listNotifications({limit: 40})
+        const filtered = res.data.notifications.filter(
+          notif => !notif.isRead && !shouldFilterNotif(notif, moderationOpts),
+        )
+        const num =
+          filtered.length >= 30
+            ? '30+'
+            : filtered.length === 0
+            ? ''
+            : String(filtered.length)
+        if (isNative) {
+          Notifications.setBadgeCountAsync(Math.min(filtered.length, 30))
+        }
+
+        // track last sync
+        const now = new Date()
+        const lastIndexed = filtered[0] && new Date(filtered[0].indexedAt)
+        lastSyncRef.current =
+          !lastIndexed || now > lastIndexed ? now : lastIndexed
+
+        // update & broadcast
+        setNumUnread(num)
+        broadcast.postMessage({event: num})
+      },
+    }
+  }, [setNumUnread, agent, moderationOpts])
+  checkUnreadRef.current = api.checkUnread
+
+  return (
+    <stateContext.Provider value={numUnread}>
+      <apiContext.Provider value={api}>{children}</apiContext.Provider>
+    </stateContext.Provider>
+  )
+}
+
+export function useUnreadNotifications() {
+  return React.useContext(stateContext)
+}
+
+export function useUnreadNotificationsApi() {
+  return React.useContext(apiContext)
+}
diff --git a/src/state/queries/notifications/util.ts b/src/state/queries/notifications/util.ts
new file mode 100644
index 000000000..c49d1851a
--- /dev/null
+++ b/src/state/queries/notifications/util.ts
@@ -0,0 +1,38 @@
+import {
+  AppBskyNotificationListNotifications,
+  ModerationOpts,
+  moderateProfile,
+  moderatePost,
+} from '@atproto/api'
+
+// TODO this should be in the sdk as moderateNotification -prf
+export function shouldFilterNotif(
+  notif: AppBskyNotificationListNotifications.Notification,
+  moderationOpts: ModerationOpts | undefined,
+): boolean {
+  if (!moderationOpts) {
+    return false
+  }
+  const profile = moderateProfile(notif.author, moderationOpts)
+  if (
+    profile.account.filter ||
+    profile.profile.filter ||
+    notif.author.viewer?.muted
+  ) {
+    return true
+  }
+  if (
+    notif.type === 'reply' ||
+    notif.type === 'quote' ||
+    notif.type === 'mention'
+  ) {
+    // NOTE: the notification overlaps the post enough for this to work
+    const post = moderatePost(notif, moderationOpts)
+    if (post.content.filter) {
+      return true
+    }
+  }
+  // TODO: thread muting is not being applied
+  // (this requires fetching the post)
+  return false
+}