gpx.studio/website/src/lib/logic/selection-statistics.ts

import { writable } from 'svelte/store';
import { engine, type GlobalStatistics } from '$lib/engine';

/** 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));