refactoring

website/src/lib/state/selection-statistics.ts

@@ -0,0 +1,20 @@
+import { writable, type Writable } from 'svelte/store';
+import { engine, type GlobalStatistics } from '$lib/engine';
+import type { Coordinates } from '$lib/geo/coordinates';
+
+/** The part of the selection that is highlighted in the elevation profile. */
+export type SlicedStatistics = {
+    /** Statistics of the part. */
+    global: GlobalStatistics;
+    /** Indices of its first and last trackpoints in the statistics of the selection. */
+    start: number;
+    end: number;
+};
+
+export const slicedStatistics = writable<SlicedStatistics | undefined>(undefined);
+
+// the indices only make sense for the selection they were made on
+engine.statistics.subscribe(() => slicedStatistics.set(undefined));
+
+/** The point of the elevation profile that the pointer is over, shown on the map. */
+export const hoveredPoint: Writable<Coordinates | null> = writable(null);