sync and cache file order

website/src/lib/components/file-list/FileListNodeContent.svelte

@@ -1,9 +1,9 @@
 <script lang="ts">
 	import { GPXFile, Track, Waypoint, type AnyGPXTreeElement, type GPXTreeElement } from 'gpx';
-	import { getContext, onDestroy, onMount } from 'svelte';
+	import { afterUpdate, getContext, onDestroy, onMount } from 'svelte';
 	import Sortable from 'sortablejs/Sortable';
-	import type { GPXFileWithStatistics } from '$lib/db';
-	import type { Readable, Writable } from 'svelte/store';
+	import { settings, type GPXFileWithStatistics } from '$lib/db';
+	import { get, type Readable, type Writable } from 'svelte/store';
 	import FileListNodeStore from './FileListNodeStore.svelte';
 	import FileListNode from './FileListNode.svelte';
 	import FileListNodeLabel from './FileListNodeLabel.svelte';
@@ -50,6 +50,25 @@
 		});
 	}
 
+	function syncFileOrder() {
+		if (sortableLevel !== 'file') {
+			return;
+		}
+		const currentOrder = sortable.toArray();
+		if (currentOrder.length !== $fileOrder.length) {
+			sortable.sort($fileOrder);
+		} else {
+			for (let i = 0; i < currentOrder.length; i++) {
+				if (currentOrder[i] !== $fileOrder[i]) {
+					sortable.sort($fileOrder);
+					break;
+				}
+			}
+		}
+	}
+
+	const { fileOrder } = settings;
+
 	onMount(() => {
 		sortable = Sortable.create(container, {
 			group: {
@@ -61,10 +80,36 @@
 			avoidImplicitDeselect: true,
 			onSelect: onSelectChange,
 			onDeselect: onSelectChange,
-			sort: sortableLevel !== 'waypoint'
+			sort: sortableLevel !== 'waypoint',
+			onSort: () => {
+				if (sortableLevel !== 'file') {
+					return;
+				}
+
+				let newFileOrder = sortable.toArray();
+				if (newFileOrder.length !== get(fileOrder).length) {
+					fileOrder.set(newFileOrder);
+					return;
+				}
+
+				for (let i = 0; i < newFileOrder.length; i++) {
+					if (newFileOrder[i] !== get(fileOrder)[i]) {
+						fileOrder.set(newFileOrder);
+						return;
+					}
+				}
+			}
 		});
 	});
 
+	$: if ($fileOrder && sortable) {
+		syncFileOrder();
+	}
+
+	afterUpdate(() => {
+		syncFileOrder();
+	});
+
 	const unsubscribe = selected.subscribe(($selected) => {
 		Object.entries(items).forEach(([id, item]) => {
 			if ($selected.has(id) && !item.classList.contains('sortable-selected')) {
@@ -98,7 +143,7 @@
 >
 	{#if node instanceof Map}
 		{#each node as [fileId, file]}
-			<div bind:this={items[fileId]}>
+			<div bind:this={items[fileId]} data-id={fileId}>
 				<FileListNodeStore {file} />
 			</div>
 		{/each}

website/src/lib/db.ts

@@ -2,7 +2,7 @@ import Dexie, { liveQuery } from 'dexie';
 import { GPXFile, GPXStatistics } from 'gpx';
 import { enableMapSet, enablePatches, applyPatches, type Patch, type WritableDraft, castDraft, Immer } from 'immer';
 import { writable, get, derived, type Readable, type Writable } from 'svelte/store';
-import { fileOrder, initTargetMapBounds, selectedFiles, updateTargetMapBounds } from './stores';
+import { initTargetMapBounds, selectedFiles, updateTargetMapBounds } from './stores';
 import { mode } from 'mode-watcher';
 import { defaultBasemap, defaultBasemapTree, defaultOverlayTree, defaultOverlays } from './assets/layers';
 
@@ -35,7 +35,7 @@ class Database extends Dexie {
 const db = new Database();
 
 // Wrap Dexie live queries in a Svelte store to avoid triggering the query for every subscriber, and updates to the store are pushed to the DB
-function dexieSettingStore(setting: string, initial: any): Writable<any> {
+function dexieSettingStore<T>(setting: string, initial: T): Writable<T> {
     let store = writable(initial);
     liveQuery(() => db.settings.get(setting)).subscribe(value => {
         if (value !== undefined) {
@@ -94,6 +94,7 @@ export const settings = {
     selectedOverlayTree: dexieSettingStore('selectedOverlayTree', defaultOverlayTree),
     directionMarkers: dexieSettingStore('directionMarkers', false),
     distanceMarkers: dexieSettingStore('distanceMarkers', false),
+    fileOrder: dexieSettingStore<string[]>('fileOrder', []),
 };
 
 // Wrap Dexie live queries in a Svelte store to avoid triggering the query for every subscriber
@@ -304,12 +305,12 @@ export const dbUtils = {
         applyToFiles([id], callback);
     },
     applyToSelectedFiles: (callback: (file: WritableDraft<GPXFile>) => GPXFile) => {
-        applyToFiles(get(fileOrder).filter(fileId => get(selectedFiles).has(fileId)), callback);
+        applyToFiles(get(settings.fileOrder).filter(fileId => get(selectedFiles).has(fileId)), callback);
     },
     duplicateSelectedFiles: () => {
         applyGlobal((draft) => {
-            let ids = getFileIds(get(fileOrder).length);
-            get(fileOrder).forEach((fileId, index) => {
+            let ids = getFileIds(get(settings.fileOrder).length);
+            get(settings.fileOrder).forEach((fileId, index) => {
                 if (get(selectedFiles).has(fileId)) {
                     let file = draft.get(fileId);
                     if (file) {

website/src/lib/stores.ts

@@ -5,14 +5,14 @@ import { GPXFile, buildGPX, parseGPX, GPXStatistics, type Coordinates } from 'gp
 import { tick } from 'svelte';
 import { _ } from 'svelte-i18n';
 import type { GPXLayer } from '$lib/components/gpx-layer/GPXLayer';
-import { dbUtils, fileObservers } from './db';
+import { dbUtils, fileObservers, settings } from './db';
 
 export const map = writable<mapboxgl.Map | null>(null);
-
-export const fileOrder = writable<string[]>([]);
 export const selectedFiles = writable<Set<string>>(new Set());
 export const selectFiles = writable<{ [key: string]: (fileId?: string) => void }>({});
 
+const { fileOrder } = settings;
+
 fileObservers.subscribe((files) => { // Update selectedFiles automatically when files are deleted (either by action or by undo-redo)
     let deletedFileIds: string[] = [];
     get(selectedFiles).forEach((fileId) => {