From 879ab272e0572b37390d13a5e3644c0f4b030c93 Mon Sep 17 00:00:00 2001
From: James Grugett <jahooma@gmail.com>
Date: Tue, 7 Jun 2022 22:24:18 -0500
Subject: [PATCH] Following and follower list (#456)

* Create following button that opens follow list in modal.

* Move react query deps to web package.json

* UseFollowers hook

* Following and followers button, dialog with tabs.

* Fix line endings

* Remove carriage return from default vscode eol

* Add placeholder message if no users followed / no followers

* Tweak spacing
---
 .vscode/settings.json               |   2 +-
 firestore.rules                     |   3 +-
 functions/package.json              |   2 -
 web/components/follow-list.tsx      |  68 ++++++++++++++++++
 web/components/following-button.tsx | 104 ++++++++++++++++++++++++++++
 web/components/user-page.tsx        |   7 +-
 web/hooks/use-follows.ts            |  12 +++-
 web/hooks/use-user.ts               |  27 ++++++++
 web/lib/firebase/users.ts           |  27 +++++++-
 web/package.json                    |   4 +-
 10 files changed, 247 insertions(+), 9 deletions(-)
 create mode 100644 web/components/follow-list.tsx
 create mode 100644 web/components/following-button.tsx

diff --git a/.vscode/settings.json b/.vscode/settings.json
index 7819cbe0..ed5544ec 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,7 +1,7 @@
 {
   "javascript.preferences.importModuleSpecifier": "shortest",
   "typescript.preferences.importModuleSpecifier": "shortest",
-  "files.eol": "\r\n",
+  "files.eol": "\n",
   "search.exclude": {
     "**/node_modules": true,
     "**/package-lock.json": true,
diff --git a/firestore.rules b/firestore.rules
index 32649752..b4a58074 100644
--- a/firestore.rules
+++ b/firestore.rules
@@ -24,9 +24,8 @@ service cloud.firestore {
       allow write: if request.auth.uid == userId;
     }
 
-    match /users/{userId}/follows/{followUserId} {
+    match /{somePath=**}/follows/{followUserId} {
       allow read;
-      allow write: if request.auth.uid == userId;
     }
 
     match /private-users/{userId} {
diff --git a/functions/package.json b/functions/package.json
index 3f3315f3..c51afd82 100644
--- a/functions/package.json
+++ b/functions/package.json
@@ -20,7 +20,6 @@
   },
   "main": "lib/functions/src/index.js",
   "dependencies": {
-    "@react-query-firebase/firestore": "0.4.2",
     "cors": "2.8.5",
     "fetch": "1.1.0",
     "firebase-admin": "10.0.0",
@@ -28,7 +27,6 @@
     "lodash": "4.17.21",
     "mailgun-js": "0.22.0",
     "module-alias": "2.2.2",
-    "react-query": "3.39.0",
     "stripe": "8.194.0",
     "zod": "3.17.2"
   },
diff --git a/web/components/follow-list.tsx b/web/components/follow-list.tsx
new file mode 100644
index 00000000..0eef1170
--- /dev/null
+++ b/web/components/follow-list.tsx
@@ -0,0 +1,68 @@
+import clsx from 'clsx'
+import { useFollows } from 'web/hooks/use-follows'
+import { useUser, useUserById } from 'web/hooks/use-user'
+import { follow, unfollow } from 'web/lib/firebase/users'
+import { Avatar } from './avatar'
+import { FollowButton } from './follow-button'
+import { Col } from './layout/col'
+import { Row } from './layout/row'
+import { UserLink } from './user-page'
+
+export function FollowList(props: { userIds: string[] }) {
+  const { userIds } = props
+  const currentUser = useUser()
+  const followedUserIds = useFollows(currentUser?.id)
+
+  const onFollow = (userId: string) => {
+    if (!currentUser) return
+    follow(currentUser.id, userId)
+  }
+  const onUnfollow = (userId: string) => {
+    if (!currentUser) return
+    unfollow(currentUser.id, userId)
+  }
+
+  return (
+    <Col className="gap-2">
+      {userIds.length === 0 && (
+        <div className="text-gray-500">No users yet...</div>
+      )}
+      {userIds.map((userId) => (
+        <UserFollowItem
+          key={userId}
+          userId={userId}
+          isFollowing={
+            followedUserIds ? followedUserIds.includes(userId) : false
+          }
+          onFollow={() => onFollow(userId)}
+          onUnfollow={() => onUnfollow(userId)}
+        />
+      ))}
+    </Col>
+  )
+}
+
+function UserFollowItem(props: {
+  userId: string
+  isFollowing: boolean
+  onFollow: () => void
+  onUnfollow: () => void
+  className?: string
+}) {
+  const { userId, isFollowing, onFollow, onUnfollow, className } = props
+  const user = useUserById(userId)
+
+  return (
+    <Row className={clsx('items-center justify-between gap-2 p-2', className)}>
+      <Row className="items-center gap-2">
+        <Avatar username={user?.username} avatarUrl={user?.avatarUrl} />
+        {user && <UserLink name={user.name} username={user.username} />}
+      </Row>
+      <FollowButton
+        isFollowing={isFollowing}
+        onFollow={onFollow}
+        onUnfollow={onUnfollow}
+      />
+    </Row>
+  )
+}
diff --git a/web/components/following-button.tsx b/web/components/following-button.tsx
new file mode 100644
index 00000000..b36ee37d
--- /dev/null
+++ b/web/components/following-button.tsx
@@ -0,0 +1,104 @@
+import { User } from 'common/user'
+import { useEffect, useState } from 'react'
+import { useFollowers, useFollows } from 'web/hooks/use-follows'
+import { prefetchUsers } from 'web/hooks/use-user'
+import { FollowList } from './follow-list'
+import { Col } from './layout/col'
+import { Modal } from './layout/modal'
+import { Tabs } from './layout/tabs'
+
+export function FollowingButton(props: { user: User }) {
+  const { user } = props
+  const [open, setOpen] = useState(false)
+  const followingIds = useFollows(user.id)
+  const followerIds = useFollowers(user.id)
+
+  return (
+    <>
+      <div
+        className="cursor-pointer gap-2 hover:underline focus:underline"
+        tabIndex={0}
+        onClick={() => setOpen(true)}
+      >
+        <span className="font-semibold">{followingIds?.length ?? ''}</span>{' '}
+        Following
+      </div>
+
+      <FollowingFollowersDialog
+        user={user}
+        defaultTab="following"
+        followingIds={followingIds ?? []}
+        followerIds={followerIds ?? []}
+        isOpen={open}
+        setIsOpen={setOpen}
+      />
+    </>
+  )
+}
+
+export function FollowersButton(props: { user: User }) {
+  const { user } = props
+  const [isOpen, setIsOpen] = useState(false)
+  const followingIds = useFollows(user.id)
+  const followerIds = useFollowers(user.id)
+
+  return (
+    <>
+      <div
+        className="cursor-pointer gap-2 hover:underline focus:underline"
+        tabIndex={0}
+        onClick={() => setIsOpen(true)}
+      >
+        <span className="font-semibold">{followerIds?.length ?? ''}</span>{' '}
+        Followers
+      </div>
+
+      <FollowingFollowersDialog
+        user={user}
+        defaultTab="followers"
+        followingIds={followingIds ?? []}
+        followerIds={followerIds ?? []}
+        isOpen={isOpen}
+        setIsOpen={setIsOpen}
+      />
+    </>
+  )
+}
+
+function FollowingFollowersDialog(props: {
+  user: User
+  followingIds: string[]
+  followerIds: string[]
+  defaultTab: 'following' | 'followers'
+  isOpen: boolean
+  setIsOpen: (isOpen: boolean) => void
+}) {
+  const { user, followingIds, followerIds, defaultTab, isOpen, setIsOpen } =
+    props
+
+  useEffect(() => {
+    prefetchUsers([...followingIds, ...followerIds])
+  }, [followingIds, followerIds])
+
+  return (
+    <Modal open={isOpen} setOpen={setIsOpen}>
+      <Col className="rounded bg-white p-6">
+        <div className="p-2 pb-1 text-xl">{user.name}</div>
+        <div className="p-2 pt-0 text-sm text-gray-500">@{user.username}</div>
+        <Tabs
+          tabs={[
+            {
+              title: 'Following',
+              content: <FollowList userIds={followingIds} />,
+            },
+            {
+              title: 'Followers',
+              content: <FollowList userIds={followerIds} />,
+            },
+          ]}
+          defaultIndex={defaultTab === 'following' ? 0 : 1}
+        />
+      </Col>
+    </Modal>
+  )
+}
diff --git a/web/components/user-page.tsx b/web/components/user-page.tsx
index 0c704056..8b63d01e 100644
--- a/web/components/user-page.tsx
+++ b/web/components/user-page.tsx
@@ -23,6 +23,7 @@ import { BetsList } from './bets-list'
 import { Bet } from 'common/bet'
 import { getUserBets } from 'web/lib/firebase/bets'
 import { uniq } from 'lodash'
+import { FollowersButton, FollowingButton } from './following-button'
 
 export function UserLink(props: {
   name: string
@@ -149,9 +150,10 @@ export function UserPage(props: {
         <span className="text-2xl font-bold">{user.name}</span>
         <span className="text-gray-500">@{user.username}</span>
 
+        <Spacer h={4} />
+
         {user.bio && (
           <>
-            <Spacer h={4} />
             <div>
               <Linkify text={user.bio}></Linkify>
             </div>
@@ -160,6 +162,9 @@ export function UserPage(props: {
         )}
 
         <Col className="sm:flex-row sm:gap-4">
+          <FollowingButton user={user} />
+          <FollowersButton user={user} />
+
           {user.website && (
             <SiteLink
               href={
diff --git a/web/hooks/use-follows.ts b/web/hooks/use-follows.ts
index a8a775d8..bd3fae3e 100644
--- a/web/hooks/use-follows.ts
+++ b/web/hooks/use-follows.ts
@@ -1,5 +1,5 @@
 import { useEffect, useState } from 'react'
-import { listenForFollows } from 'web/lib/firebase/users'
+import { listenForFollowers, listenForFollows } from 'web/lib/firebase/users'
 
 export const useFollows = (userId: string | undefined) => {
   const [followIds, setFollowIds] = useState<string[] | undefined>()
@@ -10,3 +10,13 @@ export const useFollows = (userId: string | undefined) => {
 
   return followIds
 }
+
+export const useFollowers = (userId: string | undefined) => {
+  const [followerIds, setFollowerIds] = useState<string[] | undefined>()
+
+  useEffect(() => {
+    if (userId) return listenForFollowers(userId, setFollowerIds)
+  }, [userId])
+
+  return followerIds
+}
diff --git a/web/hooks/use-user.ts b/web/hooks/use-user.ts
index bd4caf6e..7641f6e2 100644
--- a/web/hooks/use-user.ts
+++ b/web/hooks/use-user.ts
@@ -1,10 +1,15 @@
 import { useEffect, useState } from 'react'
+import { useFirestoreDocumentData } from '@react-query-firebase/firestore'
+import { QueryClient } from 'react-query'
+
+import { DocumentData } from 'firebase/firestore'
 import { PrivateUser } from 'common/user'
 import {
   listenForLogin,
   listenForPrivateUser,
   listenForUser,
   User,
+  userDocRef,
 } from 'web/lib/firebase/users'
 import { useStateCheckEquality } from './use-state-check-equality'
 
@@ -35,3 +40,25 @@ export const usePrivateUser = (userId?: string) => {
 
   return privateUser
 }
+
+export const useUserById = (userId: string) => {
+  const result = useFirestoreDocumentData<DocumentData, User>(
+    ['users', userId],
+    userDocRef(userId),
+    { subscribe: true, includeMetadataChanges: true }
+  )
+
+  return result.isLoading ? undefined : result.data
+}
+
+const queryClient = new QueryClient()
+
+export const prefetchUser = (userId: string) => {
+  queryClient.prefetchQuery(['users', userId])
+}
+
+export const prefetchUsers = (userIds: string[]) => {
+  userIds.forEach((userId) => {
+    queryClient.prefetchQuery(['users', userId])
+  })
+}
diff --git a/web/lib/firebase/users.ts b/web/lib/firebase/users.ts
index 61b4fbb3..344ba7e6 100644
--- a/web/lib/firebase/users.ts
+++ b/web/lib/firebase/users.ts
@@ -11,6 +11,8 @@ import {
   orderBy,
   updateDoc,
   deleteDoc,
+  collectionGroup,
+  onSnapshot,
 } from 'firebase/firestore'
 import { getAuth } from 'firebase/auth'
 import { ref, getStorage, uploadBytes, getDownloadURL } from 'firebase/storage'
@@ -29,14 +31,17 @@ import { DAY_MS } from 'common/util/time'
 import { feed } from 'common/feed'
 import { CATEGORY_LIST } from 'common/categories'
 import { safeLocalStorage } from '../util/local'
+import { filterDefined } from 'common/util/array'
 
 export type { User }
 
 const db = getFirestore(app)
 export const auth = getAuth(app)
 
+export const userDocRef = (userId: string) => doc(db, 'users', userId)
+
 export async function getUser(userId: string) {
-  const docSnap = await getDoc(doc(db, 'users', userId))
+  const docSnap = await getDoc(userDocRef(userId))
   return docSnap.data() as User
 }
 
@@ -263,3 +268,23 @@ export function listenForFollows(
     setFollowIds(docs.map(({ userId }) => userId))
   )
 }
+
+export function listenForFollowers(
+  userId: string,
+  setFollowerIds: (followerIds: string[]) => void
+) {
+  const followersQuery = query(
+    collectionGroup(db, 'follows'),
+    where('userId', '==', userId)
+  )
+  return onSnapshot(
+    followersQuery,
+    { includeMetadataChanges: true },
+    (snapshot) => {
+      if (snapshot.metadata.fromCache) return
+
+      const values = snapshot.docs.map((doc) => doc.ref.parent.parent?.id)
+      setFollowerIds(filterDefined(values))
+    }
+  )
+}
diff --git a/web/package.json b/web/package.json
index 889265c9..35b71341 100644
--- a/web/package.json
+++ b/web/package.json
@@ -21,6 +21,7 @@
     "@heroicons/react": "1.0.5",
     "@nivo/core": "0.74.0",
     "@nivo/line": "0.74.0",
+    "@react-query-firebase/firestore": "0.4.2",
     "algoliasearch": "4.13.0",
     "clsx": "1.1.1",
     "cors": "2.8.5",
@@ -37,7 +38,8 @@
     "react-dom": "17.0.2",
     "react-expanding-textarea": "2.3.5",
     "react-hot-toast": "^2.2.0",
-    "react-instantsearch-hooks-web": "6.24.1"
+    "react-instantsearch-hooks-web": "6.24.1",
+    "react-query": "3.39.0"
   },
   "devDependencies": {
     "@tailwindcss/forms": "0.4.0",