Massive/PlanItem.tsx

import {
  NavigationProp,
  useFocusEffect,
  useNavigation,
} from '@react-navigation/native'
import {useCallback, useMemo, useState} from 'react'
import {Text} from 'react-native'
import {List} from 'react-native-paper'
import {getLast} from './best.service'
import {DARK_RIPPLE, LIGHT_RIPPLE} from './constants'
import {defaultSet} from './gym-set'
import {Plan} from './plan'
import {PlanPageParams} from './plan-page-params'
import {DAYS} from './time'
import useDark from './use-dark'

export default function PlanItem({
  item,
  setIds,
  ids,
}: {
  item: Plan
  ids: number[]
  setIds: (value: number[]) => void
}) {
  const [today, setToday] = useState<string>()
  const dark = useDark()
  const days = useMemo(() => item.days.split(','), [item.days])
  const navigation = useNavigation<NavigationProp<PlanPageParams>>()

  useFocusEffect(
    useCallback(() => {
      const newToday = DAYS[new Date().getDay()]
      setToday(newToday)
    }, []),
  )

  const start = useCallback(async () => {
    const workout = item.workouts.split(',')[0]
    let first = await getLast(workout)
    if (!first) first = {...defaultSet, name: workout}
    delete first.id
    if (ids.length === 0)
      return navigation.navigate('StartPlan', {plan: item, first})
    const removing = ids.find(id => id === item.id)
    if (removing) setIds(ids.filter(id => id !== item.id))
    else setIds([...ids, item.id])
  }, [ids, setIds, item, navigation])

  const longPress = useCallback(() => {
    if (ids.length > 0) return
    setIds([item.id])
  }, [ids.length, item.id, setIds])

  const title = useMemo(
    () =>
      days.map((day, index) => (
        <Text key={day}>
          {day === today ? (
            <Text style={{fontWeight: 'bold', textDecorationLine: 'underline'}}>
              {day}
            </Text>
          ) : (
            day
          )}
          {index === days.length - 1 ? '' : ', '}
        </Text>
      )),
    [days, today],
  )

  const description = useMemo(
    () => item.workouts.replace(/,/g, ', '),
    [item.workouts],
  )

  const backgroundColor = useMemo(() => {
    if (!ids.includes(item.id)) return
    if (dark) return DARK_RIPPLE
    return LIGHT_RIPPLE
  }, [dark, ids, item.id])

  return (
    <List.Item
      onPress={start}
      title={title}
      description={description}
      onLongPress={longPress}
      style={{backgroundColor}}
    />
  )
}