3 files changed, 91 insertions, 0 deletions
diff --git a/src/utils/hooks/use-posts-list/index.ts b/src/utils/hooks/use-posts-list/index.ts
new file mode 100644
index 0000000..664c142
--- /dev/null
+++ b/src/utils/hooks/use-posts-list/index.ts
@@ -0,0 +1 @@
+export * from './use-posts-list';
diff --git a/src/utils/hooks/use-posts-list/use-posts-list.test.ts b/src/utils/hooks/use-posts-list/use-posts-list.test.ts
new file mode 100644
index 0000000..1d11111
--- /dev/null
+++ b/src/utils/hooks/use-posts-list/use-posts-list.test.ts
@@ -0,0 +1,24 @@
+import { describe, expect, it } from '@jest/globals';
+import { act, renderHook } from '@testing-library/react';
+import { getArticles } from '../../../services/graphql';
+import { usePostsList } from './use-posts-list';
+
+describe('usePostsList', () => {
+  it('can return the first new result index when loading more posts', async () => {
+    const perPage = 5;
+    const { result } = renderHook(() =>
+      usePostsList({ fetcher: getArticles, perPage })
+    );
+
+    expect.assertions(2);
+
+    expect(result.current.firstNewResultIndex).toBeUndefined();
+
+    await act(async () => {
+      await result.current.loadMore();
+    });
+
+    // Assuming there is more than one page.
+    expect(result.current.firstNewResultIndex).toBe(perPage + 1);
+  });
+});
diff --git a/src/utils/hooks/use-posts-list/use-posts-list.ts b/src/utils/hooks/use-posts-list/use-posts-list.ts
new file mode 100644
index 0000000..661727f
--- /dev/null
+++ b/src/utils/hooks/use-posts-list/use-posts-list.ts
@@ -0,0 +1,66 @@
+import { useCallback, useState } from 'react';
+import type { PostData } from '../../../components';
+import type { Maybe, RawArticle } from '../../../types';
+import { getPostsList } from '../../helpers';
+import {
+  type UsePaginationConfig,
+  usePagination,
+  type UsePaginationReturn,
+} from '../use-pagination';
+
+export type usePostsListReturn = Omit<
+  UsePaginationReturn<RawArticle>,
+  'data'
+> & {
+  /**
+   * The index of the first new result when loading more posts.
+   */
+  firstNewResultIndex: Maybe<number>;
+  /**
+   * The posts list.
+   */
+  posts: Maybe<PostData[]>;
+};
+
+export const usePostsList = (
+  config: UsePaginationConfig<RawArticle>
+): usePostsListReturn => {
+  const {
+    data,
+    error,
+    hasNextPage,
+    isEmpty,
+    isError,
+    isLoading,
+    isLoadingMore,
+    isRefreshing,
+    isValidating,
+    loadMore,
+    size,
+  } = usePagination(config);
+  const [firstNewResultIndex, setFirstNewResultIndex] =
+    useState<Maybe<number>>(undefined);
+
+  const posts = data ? getPostsList(data) : undefined;
+
+  const handleLoadMore = useCallback(async () => {
+    setFirstNewResultIndex(size * config.perPage + 1);
+
+    await loadMore();
+  }, [config.perPage, loadMore, size]);
+
+  return {
+    error,
+    firstNewResultIndex,
+    hasNextPage,
+    isEmpty,
+    isError,
+    isLoading,
+    isLoadingMore,
+    isRefreshing,
+    isValidating,
+    loadMore: handleLoadMore,
+    posts,
+    size,
+  };
+};