under-falling-skies/src/lib/store/api.js

import * as R from 'remeda';
import Dexie, { liveQuery } from 'dexie';
import { writable, derived } from 'svelte/store';
import { genNextBattle } from './genNextBattle.js';

const seedCampaign = {
    battles: [],
};

export function genApi(options = {}) {
    const storage = new Dexie('Campaigns', options.dexie ?? {});

    storage.version(1).stores({
        campaigns: '++id,name',
    });

    const campaigns = writable([]);
    storage.campaigns.toArray().then((c) => campaigns.set(c));

    const activeCampaignId = writable();

    const activeCampaign = derived(
        [activeCampaignId, campaigns],
        async ([id, campaigns], set) => {
            const x = campaigns.find((c) => c.id === id);
            set(x);
        },
    );

    return {
        campaigns,
        activeCampaign,
        storage,
        event: {
            addCampaign: (name) =>
                storage.campaigns.add({
                    name,
                    ...seedCampaign,
                    battles: [genNextBattle()],
                }),
            deleteCampaign: (id) => storage.campaigns.delete(id),
            setActiveCampaign: async (id) => {
                activeCampaignId.set(id);
            },
        },
    };
}