Refactored many helpers to Typescript

src/utils/helpers/pagination.ts

@@ -0,0 +1,29 @@
+import { max, min, range } from 'ramda';
+
+export const ELLIPSIS = '...';
+
+type NumberOrEllipsis = number | '...';
+
+export const progressivePagination = (currentPage: number, pageCount: number): NumberOrEllipsis[] => {
+  const delta = 2;
+  const pages: NumberOrEllipsis[] = range(
+    max(delta, currentPage - delta),
+    min(pageCount - 1, currentPage + delta) + 1,
+  );
+
+  if (currentPage - delta > delta) {
+    pages.unshift(ELLIPSIS);
+  }
+  if (currentPage + delta < pageCount - 1) {
+    pages.push(ELLIPSIS);
+  }
+
+  pages.unshift(1);
+  pages.push(pageCount);
+
+  return pages;
+};
+
+export const keyForPage = (pageNumber: NumberOrEllipsis, index: number) => pageNumber !== ELLIPSIS ? pageNumber : `${pageNumber}_${index}`;
+
+export const isPageDisabled = (pageNumber: NumberOrEllipsis) => pageNumber === ELLIPSIS;