fix: normalize artist timestamp units for New additions

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Fixed
+
+- Normalize artist timestamp parsing in the frontend New additions view to correctly handle seconds/milliseconds and ignore invalid values. [#289](https://github.com/pSpitzner/beets-flask/issues/289)
+
 ## [1.2.1] - 25-12-28
 
 ### Fixed

backend/beets_flask/importer/session.py

@@ -271,10 +271,10 @@ def get_config_value(self, key: str, type_func: Callable | None = None) -> Any:
         # get settings from user settings, this is not a dict, but confuse config
         # the confuse config views do not throw key errors, and their .get() is not
         # the same as dict.get(), but rather resolves the value.
-        default = get_config()
+        config_view = get_config()
         for p in path:
-            default = default[p]
-        default = default.get(type_func) if type_func else default.get()
+            config_view = config_view[p]
+        default = config_view.get(type_func) if type_func else config_view.get()
         return default
 
     # -------------------------- State handling helpers -------------------------- #

frontend/src/api/library.ts

@@ -1,6 +1,7 @@
 import { infiniteQueryOptions, queryOptions } from '@tanstack/react-query';
 
 import { toHex } from '@/components/common/strings';
+import { parseApiDate } from '@/components/common/units/time';
 import {
     AlbumResponse,
     AlbumResponseExpanded,
@@ -272,19 +273,10 @@ export const artistsQueryOptions = () => ({
 
         for (let i = 0; i < artists.length; i++) {
             const artist = artists[i];
-            // Convert timestamps to Date objects
-            if (artist.last_item_added) {
-                artist.last_item_added = new Date(artist.last_item_added);
-            }
-            if (artist.last_album_added) {
-                artist.last_album_added = new Date(artist.last_album_added);
-            }
-            if (artist.first_item_added) {
-                artist.first_item_added = new Date(artist.first_item_added);
-            }
-            if (artist.first_album_added) {
-                artist.first_album_added = new Date(artist.first_album_added);
-            }
+            artist.last_item_added = parseApiDate(artist.last_item_added);
+            artist.last_album_added = parseApiDate(artist.last_album_added);
+            artist.first_item_added = parseApiDate(artist.first_item_added);
+            artist.first_album_added = parseApiDate(artist.first_album_added);
         }
         return artists;
         // TODO: fill cache data for single artists queries

frontend/src/components/common/units/time.tsx

@@ -1,3 +1,24 @@
+export const parseApiDate = (value: unknown): Date | undefined => {
+    if (value === null || value === undefined) {
+        return undefined;
+    }
+
+    const numeric = typeof value === 'number' ? value : Number(value);
+    if (!Number.isNaN(numeric)) {
+        // Some API responses provide UNIX seconds while others use milliseconds.
+        const timestamp = numeric < 1e12 ? numeric * 1000 : numeric;
+        const date = new Date(timestamp);
+        return Number.isNaN(date.getTime()) ? undefined : date;
+    }
+
+    if (typeof value === 'string') {
+        const date = new Date(value);
+        return Number.isNaN(date.getTime()) ? undefined : date;
+    }
+
+    return undefined;
+};
+
 export const relativeTime = (date?: Date | null) => {
     if (!date) return 'never';