New: Delete files for Select Series

Closes #5110

frontend/src/Series/Index/Select/Delete/useSelectedSeriesStats.ts

@@ -0,0 +1,45 @@
+import { useMemo } from 'react';
+import { useSelect } from 'App/Select/SelectContext';
+import Series from 'Series/Series';
+import useSeries from 'Series/useSeries';
+import sortByProp from 'Utilities/Array/sortByProp';
+
+function useSelectedSeriesStats() {
+  const { data: allSeries } = useSeries();
+  const { useSelectedIds } = useSelect<Series>();
+  const seriesIds = useSelectedIds();
+
+  const series = useMemo((): Series[] => {
+    const seriesList = seriesIds.map((id) => {
+      return allSeries.find((s) => s.id === id);
+    }) as Series[];
+
+    return seriesList.sort(sortByProp('sortTitle'));
+  }, [allSeries, seriesIds]);
+
+  const { totalEpisodeFileCount, totalSizeOnDisk } = useMemo(() => {
+    return series.reduce(
+      (acc, { statistics = {} }) => {
+        const { episodeFileCount = 0, sizeOnDisk = 0 } = statistics;
+
+        acc.totalEpisodeFileCount += episodeFileCount;
+        acc.totalSizeOnDisk += sizeOnDisk;
+
+        return acc;
+      },
+      {
+        totalEpisodeFileCount: 0,
+        totalSizeOnDisk: 0,
+      }
+    );
+  }, [series]);
+
+  return {
+    series,
+    seriesIds,
+    totalEpisodeFileCount,
+    totalSizeOnDisk,
+  };
+}
+
+export default useSelectedSeriesStats;