spotters: most-active-in sort with country/region selector, collection tracking (seen marks, progress, filters), refresh scripts score activity and report new NL entries

src/lib/spotting/seen.svelte.ts

@@ -0,0 +1,50 @@
+// Client-side collection state for the spotting pokedexes: optimistic overrides on top of
+// what the server sent, so a toggle updates every card/panel for that entry at once.
+import { invalidateAll } from '$app/navigation';
+
+export type SpotTracker = 'cars' | 'planes' | 'trains' | 'wildlife';
+
+const overrides = $state<Record<string, boolean>>({});
+const key = (tracker: SpotTracker, id: number) => `${tracker}:${id}`;
+
+export function isSeen(tracker: SpotTracker, id: number, fromServer: boolean): boolean {
+	const k = key(tracker, id);
+	return k in overrides ? overrides[k] : fromServer;
+}
+
+/** Owner-only POST; reverts the optimistic state when the server refuses. */
+export async function saveSeen(
+	tracker: SpotTracker,
+	id: number,
+	seen: boolean,
+	extra: { seenOn?: string | null; note?: string | null } = {}
+): Promise<boolean> {
+	const k = key(tracker, id);
+	const before = k in overrides ? overrides[k] : undefined;
+	overrides[k] = seen;
+	try {
+		const res = await fetch(`/trackers/${tracker}/seen`, {
+			method: 'POST',
+			headers: { 'content-type': 'application/json' },
+			body: JSON.stringify({ id, seen, ...extra })
+		});
+		if (!res.ok) throw new Error(String(res.status));
+		await invalidateAll();
+		delete overrides[k];
+		return true;
+	} catch {
+		if (before === undefined) delete overrides[k];
+		else overrides[k] = before;
+		return false;
+	}
+}
+
+type HasSeen = { id: number; seen: boolean };
+/** How many of these entries are collected (respecting optimistic toggles). */
+export const countSeen = (tracker: SpotTracker, items: HasSeen[]) =>
+	items.reduce((n, x) => n + (isSeen(tracker, x.id, x.seen) ? 1 : 0), 0);
+/** Client-side ?got= filter for group pages that list every entry at once. */
+export function filterGot<T extends HasSeen>(tracker: SpotTracker, items: T[], got: string): T[] {
+	if (got !== 'yes' && got !== 'no') return items;
+	return items.filter((x) => isSeen(tracker, x.id, x.seen) === (got === 'yes'));
+}