New onboarding (#241)

* delete old onboarding files and code

* add custom FollowButton component to Post, FeedItem, & ProfileCard

* move building suggested feed into helper lib

* show suggested posts/feed if follower list is empty

* Update tsconfig.json

* add pagination to getting new onboarding

* remove unnecessary console log

* fix naming, add better null check for combinedCursor

* In locally-combined feeds, correctly produce an undefined cursor when out of data

* Minor refactors of the suggested posts lib functions

* Show 'follow button' style of post meta in certain conditions only

* Only show follow btn in posts on the main feed and the discovery feed

* Add a welcome notice to the home feed

* Tune the timing of when the welcome banner shows or hides

* Make the follow button an observer (closes #244)

* Update postmeta to keep the follow btn after press until next render

* A couple of fixes that ensure consistent welcome screen

* Fix lint

* Rework the welcome banner

* Fix cache invalidation of follows model on user switch

* Show welcome banner while loading

* Update the home onboarding feed to get top posts from hardcode recommends

* Drop unused helper function

* Update happy path tests

---------

Co-authored-by: Paul Frazee <pfrazee@gmail.com>

src/state/models/suggested-posts-view.ts

@@ -1,21 +1,12 @@
 import {makeAutoObservable, runInAction} from 'mobx'
-import {
-  AppBskyFeedFeedViewPost,
-  AppBskyFeedGetAuthorFeed as GetAuthorFeed,
-} from '@atproto/api'
-type ReasonRepost = AppBskyFeedFeedViewPost.ReasonRepost
 import {RootStoreModel} from './root-store'
 import {FeedItemModel} from './feed-view'
 import {cleanError} from 'lib/strings/errors'
-
-const TEAM_HANDLES = [
-  'jay.bsky.social',
-  'paul.bsky.social',
-  'dan.bsky.social',
-  'divy.bsky.social',
-  'why.bsky.social',
-  'iamrosewang.bsky.social',
-]
+import {TEAM_HANDLES} from 'lib/constants'
+import {
+  getMultipleAuthorsPosts,
+  mergePosts,
+} from 'lib/api/build-suggested-posts'
 
 export class SuggestedPostsView {
   // state
@@ -54,15 +45,18 @@ export class SuggestedPostsView {
   async setup() {
     this._xLoading()
     try {
-      const responses = await Promise.all(
-        TEAM_HANDLES.map(handle =>
-          this.rootStore.api.app.bsky.feed
-            .getAuthorFeed({author: handle, limit: 10})
-            .catch(_err => ({success: false, headers: {}, data: {feed: []}})),
-        ),
+      const responses = await getMultipleAuthorsPosts(
+        this.rootStore,
+        TEAM_HANDLES(String(this.rootStore.agent.service)),
       )
       runInAction(() => {
-        this.posts = mergeAndFilterResponses(this.rootStore, responses)
+        const finalPosts = mergePosts(responses, {repostsOnly: true})
+        // hydrate into models
+        this.posts = finalPosts.map((post, i) => {
+          // strip the reasons to hide that these are reposts
+          delete post.reason
+          return new FeedItemModel(this.rootStore, `post-${i}`, post)
+        })
       })
       this._xIdle()
     } catch (e: any) {
@@ -90,59 +84,3 @@ export class SuggestedPostsView {
     }
   }
 }
-
-function mergeAndFilterResponses(
-  store: RootStoreModel,
-  responses: GetAuthorFeed.Response[],
-): FeedItemModel[] {
-  let posts: AppBskyFeedFeedViewPost.Main[] = []
-
-  // merge into one array
-  for (const res of responses) {
-    if (res.success) {
-      posts = posts.concat(res.data.feed)
-    }
-  }
-
-  // filter down to reposts of other users
-  const now = Date.now()
-  const uris = new Set()
-  posts = posts.filter(p => {
-    if (isARepostOfSomeoneElse(p) && isRecentEnough(now, p)) {
-      if (uris.has(p.post.uri)) {
-        return false
-      }
-      uris.add(p.post.uri)
-      return true
-    }
-    return false
-  })
-
-  // sort by index time
-  posts.sort((a, b) => {
-    return (
-      Number(new Date(b.post.indexedAt)) - Number(new Date(a.post.indexedAt))
-    )
-  })
-
-  // hydrate into models and strip the reasons to hide that these are reposts
-  return posts.map((post, i) => {
-    delete post.reason
-    return new FeedItemModel(store, `post-${i}`, post)
-  })
-}
-
-function isARepostOfSomeoneElse(post: AppBskyFeedFeedViewPost.Main): boolean {
-  return (
-    post.reason?.$type === 'app.bsky.feed.feedViewPost#reasonRepost' &&
-    post.post.author.did !== (post.reason as ReasonRepost).by.did
-  )
-}
-
-const THREE_DAYS = 3 * 24 * 60 * 60 * 1000
-function isRecentEnough(
-  now: number,
-  post: AppBskyFeedFeedViewPost.Main,
-): boolean {
-  return now - Number(new Date(post.post.indexedAt)) < THREE_DAYS
-}