bsky-app/src/lib/api/build-suggested-posts.ts
2023-04-06 16:28:45 -05:00

137 lines
3.1 KiB
TypeScript

import {RootStoreModel} from 'state/index'
import {
AppBskyFeedDefs,
AppBskyFeedGetAuthorFeed as GetAuthorFeed,
} from '@atproto/api'
type ReasonRepost = AppBskyFeedDefs.ReasonRepost
async function getMultipleAuthorsPosts(
rootStore: RootStoreModel,
authors: string[],
cursor: string | undefined = undefined,
limit: number = 10,
) {
const responses = await Promise.all(
authors.map((actor, index) =>
rootStore.agent
.getAuthorFeed({
actor,
limit,
cursor: cursor ? cursor.split(',')[index] : undefined,
})
.catch(_err => ({success: false, headers: {}, data: {feed: []}})),
),
)
return responses
}
function mergePosts(
responses: GetAuthorFeed.Response[],
{repostsOnly, bestOfOnly}: {repostsOnly?: boolean; bestOfOnly?: boolean},
) {
let posts: AppBskyFeedDefs.FeedViewPost[] = []
if (bestOfOnly) {
for (const res of responses) {
if (res.success) {
// filter the feed down to the post with the most likes
res.data.feed = res.data.feed.reduce(
(acc: AppBskyFeedDefs.FeedViewPost[], v) => {
if (
!acc?.[0] &&
!v.reason &&
!v.reply &&
isRecentEnough(v.post.indexedAt)
) {
return [v]
}
if (
acc &&
!v.reason &&
!v.reply &&
(v.post.likeCount || 0) > (acc[0]?.post.likeCount || 0) &&
isRecentEnough(v.post.indexedAt)
) {
return [v]
}
return acc
},
[],
)
}
}
}
// 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 uris = new Set()
posts = posts.filter(p => {
if (repostsOnly && !isARepostOfSomeoneElse(p)) {
return false
}
if (uris.has(p.post.uri)) {
return false
}
uris.add(p.post.uri)
return true
})
// sort by index time
posts.sort((a, b) => {
return (
Number(new Date(b.post.indexedAt)) - Number(new Date(a.post.indexedAt))
)
})
return posts
}
function isARepostOfSomeoneElse(post: AppBskyFeedDefs.FeedViewPost): boolean {
return (
post.reason?.$type === 'app.bsky.feed.defs#reasonRepost' &&
post.post.author.did !== (post.reason as ReasonRepost).by.did
)
}
function getCombinedCursors(responses: GetAuthorFeed.Response[]) {
let hasCursor = false
const cursors = responses.map(r => {
if (r.data.cursor) {
hasCursor = true
return r.data.cursor
}
return ''
})
if (!hasCursor) {
return undefined
}
const combinedCursors = cursors.join(',')
return combinedCursors
}
function isCombinedCursor(cursor: string) {
return cursor.includes(',')
}
const TWO_DAYS_AGO = Date.now() - 1e3 * 60 * 60 * 48
function isRecentEnough(date: string) {
try {
const d = Number(new Date(date))
return d > TWO_DAYS_AGO
} catch {
return false
}
}
export {
getMultipleAuthorsPosts,
mergePosts,
getCombinedCursors,
isCombinedCursor,
}