tooot/src/screens/Tabs/Shared/Toot.tsx

import Timeline from '@components/Timeline'
import TimelineDefault from '@components/Timeline/Default'
import { useNavigation } from '@react-navigation/native'
import { TabSharedStackScreenProps } from '@utils/navigation/navigators'
import { QueryKeyTimeline } from '@utils/queryHooks/timeline'
import React, { useCallback, useEffect, useRef, useState } from 'react'
import { FlatList } from 'react-native'
import { InfiniteQueryObserver, useQueryClient } from 'react-query'
import * as Sentry from 'sentry-expo'

const TabSharedToot: React.FC<TabSharedStackScreenProps<'Tab-Shared-Toot'>> = ({
  route: {
    params: { toot, rootQueryKey }
  }
}) => {
  const queryKey: QueryKeyTimeline = [
    'Timeline',
    { page: 'Toot', toot: toot.id }
  ]

  const flRef = useRef<FlatList>(null)

  const [itemsLength, setItemsLength] = useState(0)
  const scrolled = useRef(false)
  const navigation = useNavigation()
  const queryClient = useQueryClient()
  const observer = new InfiniteQueryObserver(queryClient, { queryKey })
  useEffect(() => {
    const unsubscribe = observer.subscribe(result => {
      if (result.isSuccess) {
        const flattenData = result.data?.pages
          ? // @ts-ignore
            result.data.pages.flatMap(d => [...d.body])
          : []
        setItemsLength(flattenData.length)
        // Auto go back when toot page is empty
        if (flattenData.length === 0) {
          navigation.goBack()
        }
        if (!scrolled.current) {
          scrolled.current = true
          const pointer = flattenData.findIndex(({ id }) => id === toot.id)
          try {
            pointer < flattenData.length &&
              setTimeout(() => {
                flRef.current?.scrollToIndex({
                  index: pointer,
                  viewOffset: 100
                })
              }, 500)
          } catch (err) {
            if (Math.random() < 0.1) {
              Sentry.Native.setExtras({
                type: 'original',
                index: pointer,
                itemsLength: flattenData.length,
                flattenData
              })
              Sentry.Native.captureException(err)
            }
          }
        }
      }
    })
    return () => unsubscribe()
  }, [scrolled.current])

  // Toot page auto scroll to selected toot
  const onScrollToIndexFailed = useCallback(
    error => {
      const offset = error.averageItemLength * error.index
      flRef.current?.scrollToOffset({ offset })
      try {
        error.index < itemsLength &&
          setTimeout(
            () =>
              flRef.current?.scrollToIndex({
                index: error.index,
                viewOffset: 100
              }),
            500
          )
      } catch (err) {
        if (Math.random() < 0.1) {
          Sentry.Native.setExtras({
            type: 'onScrollToIndexFailed',
            index: error.index,
            itemsLength
          })
          Sentry.Native.captureException(err)
        }
      }
    },
    [itemsLength]
  )

  const renderItem = useCallback(
    ({ item }) => (
      <TimelineDefault
        item={item}
        queryKey={queryKey}
        rootQueryKey={rootQueryKey}
        highlighted={toot.id === item.id}
      />
    ),
    []
  )

  return (
    <Timeline
      flRef={flRef}
      queryKey={queryKey}
      customProps={{ renderItem, onScrollToIndexFailed }}
      disableRefresh
      disableInfinity
    />
  )
}

export default TabSharedToot