dyomedea/src/db/change-handler.ts

import { debounce, slice } from 'lodash';
import { getWpt } from '../db/wpt';
import { returnAgain } from '../workers/dispatcher-worker';
import { getAllGpxes, getGpx } from './gpx';
import { put } from './lib';
import { getOverlays } from './overlays';
import { getRte } from './rte';
import { getTrk } from './trk';
import { getTrkseg } from './trkseg';

declare global {
  var watches: Map<string, any>;
}

const methods = {
  getAllGpxes,
  getGpx,
  getTrk,
  getTrkseg,
  getWpt,
  getRte,
  getOverlays,
};

const sendUpdate = async (params: any) => {
  if (params) {
    console.log({ caller: 'ChangeHandler / sendUpdate', params });
    const { method, _dispatchId, id, ...otherParams } = params;
    const returnValue = await methods[<keyof typeof methods>method](params);
    if (returnValue) {
      returnAgain(_dispatchId, returnValue);
    }
  }
};

let debouncedSendUpdates = <any>{};

for (const property in methods) {
  debouncedSendUpdates[<keyof typeof debouncedSendUpdates>property] = debounce(
    sendUpdate,
    500
  );
}

const changeHandler = async (change: any) => {
  // console.log({ caller: 'ChangeHandler', change, watches: globalThis.watches });
  const { id } = change;
  if (!globalThis.watches) {
    globalThis.watches = new Map();
  }
  sendUpdate(globalThis.watches.get(id));

  const tokens = id.split('/').slice(0, -1);
  if (['1wpt', '2rte', '3trk'].includes(tokens.at(-1))) {
    tokens.splice(-1);
  }
  const parentId = tokens.join('/');
  // console.log({
  //   caller: 'ChangeHandler',
  //   change,
  //   watches: globalThis.watches,
  //   parentId,
  // });

  if (parentId === 'gpx') {
    const gpxes = await getAllGpxes();
    //    console.log({ caller: 'changeHandler / gpxes', gpxes, id });
    if (!gpxes.includes(id)) {
      await put(
        parentId,
        `idx-${parentId}`,
        (doc) => {
          // console.log({ caller: 'changeHandler / gpxes', doc });
          doc.push(id);
          doc.reverse().sort().reverse();
          return doc;
        },
        []
      );
    }
  }

  const parentParams = globalThis.watches.get(parentId);
  if (parentParams) {
    debouncedSendUpdates[parentParams.method](parentParams);
  }
};

export default changeHandler;

export const getAndWatch = async (params: any) => {
  // console.log({
  //   caller: 'ChangeHandler / getAndWatch',
  //   params,
  //   watches: globalThis.watches,
  // });
  const { method, _dispatchId, id, ...otherParams } = params;
  if (!globalThis.watches) {
    globalThis.watches = new Map();
  }
  globalThis.watches.set(id, params);
  const returnValue = await methods[<keyof typeof methods>method](params);
  // console.log({
  //   caller: 'ChangeHandler / getAndWatch',
  //   params,
  //   returnValue,
  //   watches: globalThis.watches,
  // });
  return returnValue;
};

export const cancelWatch = (params: any) => {
  if (!globalThis.watches) {
    globalThis.watches = new Map();
  }
  const { id } = params;
  globalThis.watches.delete(id);
};