1 files changed, 93 insertions, 0 deletions

diff --git a/viewer/src/services/itemComparator.ts b/viewer/src/services/itemComparator.ts
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+++ b/viewer/src/services/itemComparator.ts
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+/* ldgallery - A static generator which turns a collection of tagged
+--             pictures into a searchable web gallery.
+--
+-- Copyright (C) 2019-2022  Guillaume FOUET
+--
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU Affero General Public License as
+-- published by the Free Software Foundation, either version 3 of the
+-- License, or (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU Affero General Public License for more details.
+--
+-- You should have received a copy of the GNU Affero General Public License
+-- along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+import { Item, ItemSortStr } from '@/@types/gallery';
+import i18n from '@/plugins/i18n';
+import { isDirectory } from './itemGuards';
+
+const { t } = i18n.global;
+
+export type ItemComparator = (left: Item, right: Item) => number;
+export type ItemSort = { name: ItemSortStr, text: string; fn: ItemComparator };
+
+function _sortByPathAsc(left: Item, right: Item): number {
+  return left.path.localeCompare(right.path, undefined, {
+    sensitivity: 'base',
+    ignorePunctuation: true,
+    numeric: true,
+  });
+}
+
+function _sortByTitleAsc(left: Item, right: Item): number {
+  return left.title.localeCompare(right.title, undefined, {
+    sensitivity: 'base',
+    ignorePunctuation: true,
+    numeric: true,
+  });
+}
+
+function _sortByDateAsc(left: Item, right: Item): number {
+  return left.datetime.localeCompare(right.datetime); // TODO: handle timezones
+}
+
+function _sortDirectoryFirst(left: Item, right: Item): number {
+  const dLeft = isDirectory(left) ? 1 : 0;
+  const dRight = isDirectory(right) ? 1 : 0;
+  return dRight - dLeft;
+}
+
+function _reverse(fn: ItemComparator): ItemComparator {
+  return (l, r) => -fn(l, r);
+}
+
+function _chain(comparators: ItemComparator[]): ItemComparator {
+  return comparators.reduce((primary, tieBreaker) => (l, r) => {
+    const primaryComparison = primary(l, r);
+    return primaryComparison !== 0 ? primaryComparison : tieBreaker(l, r);
+  });
+}
+
+// ---
+
+export const useItemComparator = () => {
+  const ITEM_SORTS: ItemSort[] = [
+    {
+      name: 'title_asc',
+      text: t('command.sort.byTitleAsc'),
+      fn: _chain([_sortDirectoryFirst, _sortByTitleAsc, _sortByPathAsc]),
+    },
+    {
+      name: 'date_asc',
+      text: t('command.sort.byDateAsc'),
+      fn: _chain([_sortDirectoryFirst, _sortByDateAsc, _sortByPathAsc]),
+    },
+    {
+      name: 'date_desc',
+      text: t('command.sort.byDateDesc'),
+      fn: _chain([_sortDirectoryFirst, _reverse(_sortByDateAsc), _sortByPathAsc]),
+    },
+  ];
+
+  const DEFAULT = ITEM_SORTS[2]; // date_desc
+
+  return {
+    ITEM_SORTS,
+    DEFAULT,
+  };
+};