refactored hooks directory

src/hooks/lab/useLab.ts

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+import { useShallowSelect } from '~/hooks/data/useShallowSelect';
+import {
+  selectLabList,
+  selectLabStatsHeroes,
+  selectLabStatsLoading,
+  selectLabStatsTags,
+  selectLabUpdatesNodes,
+} from '~/redux/lab/selectors';
+import { useDispatch } from 'react-redux';
+import { useCallback, useEffect } from 'react';
+import { labGetList, labGetMore, labGetStats } from '~/redux/lab/actions';
+
+export const useLab = () => {
+  const { is_loading: isLoading, nodes, count } = useShallowSelect(selectLabList);
+  const dispatch = useDispatch();
+  const tags = useShallowSelect(selectLabStatsTags);
+  const heroes = useShallowSelect(selectLabStatsHeroes);
+  const isLoadingStats = useShallowSelect(selectLabStatsLoading);
+  const updates = useShallowSelect(selectLabUpdatesNodes);
+
+  useEffect(() => {
+    dispatch(labGetList());
+    dispatch(labGetStats());
+  }, [dispatch]);
+
+  const onLoadMore = useCallback(() => {
+    if (nodes.length >= count) {
+      return;
+    }
+
+    dispatch(labGetMore());
+  }, [nodes, count, dispatch]);
+
+  return { isLoading, nodes, count, onLoadMore, tags, heroes, isLoadingStats, updates };
+};

src/hooks/lab/useLabPagination.ts

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+import { useCallback, useEffect, useMemo } from 'react';
+
+export const useLabPagination = (
+  isLoading: boolean,
+  columns: Element[],
+  onLoadMore: () => void
+) => {
+  const loadOnIntersection = useCallback<IntersectionObserverCallback>(
+    entries => {
+      const isVisible = entries.some(entry => entry.intersectionRatio > 0);
+
+      if (!isVisible) {
+        return;
+      }
+
+      onLoadMore();
+    },
+    [onLoadMore]
+  );
+
+  const observer = useMemo(
+    () =>
+      new IntersectionObserver(loadOnIntersection, {
+        threshold: [0],
+      }),
+    [loadOnIntersection]
+  );
+
+  useEffect(() => {
+    if (isLoading) {
+      return;
+    }
+
+    const lastItems = Array.from(columns)
+      .map(col => col.children.item(col.childNodes.length - 1))
+      .filter(el => el) as Element[];
+
+    lastItems.forEach(item => observer.observe(item));
+
+    return () => {
+      lastItems.forEach(item => observer.unobserve(item));
+    };
+  }, [observer, columns, isLoading]);
+};