import type { Paginator, WsEvents } from 'masto' import { useDeactivated } from './lifecycle' import type { PaginatorState } from '~/types' export function usePaginator( paginator: Paginator, stream?: WsEvents, eventType: 'notification' | 'update' = 'update', preprocess: (items: T[]) => T[] = (items: T[]) => items, ) { const state = ref(isMastoInitialised.value ? 'idle' : 'loading') const items = ref([]) const nextItems = ref([]) const prevItems = ref([]) const endAnchor = ref() const bound = reactive(useElementBounding(endAnchor)) const isInScreen = $computed(() => bound.top < window.innerHeight * 2) const error = ref() const deactivated = useDeactivated() async function update() { items.value.unshift(...prevItems.value) prevItems.value = [] } stream?.on(eventType, (status) => { if ('uri' in status) cacheStatus(status, undefined, true) prevItems.value.unshift(status as any) }) // TODO: update statuses stream?.on('status.update', (status) => { cacheStatus(status, undefined, true) const index = items.value.findIndex((s: any) => s.id === status.id) if (index >= 0) items.value[index] = status as any }) stream?.on('delete', (id) => { removeCachedStatus(id) const index = items.value.findIndex((s: any) => s.id === id) if (index >= 0) items.value.splice(index, 1) }) async function loadNext() { if (state.value !== 'idle') return state.value = 'loading' try { const result = await paginator.next() if (result.value?.length) { nextItems.value = preprocess(result.value) as any items.value.push(...nextItems.value) state.value = 'idle' } else { state.value = 'done' } } catch (e) { error.value = e state.value = 'error' } await nextTick() bound.update() } if (process.client) { useIntervalFn(() => { bound.update() }, 1000) if (!isMastoInitialised.value) { watchOnce(isMastoInitialised, () => { state.value = 'idle' loadNext() }) } watch( () => [isInScreen, state], () => { if ( isInScreen && state.value === 'idle' // No new content is loaded when the keepAlive page enters the background && deactivated.value === false ) loadNext() }, { immediate: true }, ) } return { items, prevItems, nextItems, update, state, error, endAnchor, } }