index.ts

/**
 * @license
 * Copyright 2019 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

// [START maps_directions_draggable]
function initMap(): void {
  const map = new google.maps.Map(
    document.getElementById("map") as HTMLElement,
    {
      zoom: 4,
      center: { lat: -24.345, lng: 134.46 }, // Australia.
    }
  );

  const directionsService = new google.maps.DirectionsService();
  const directionsRenderer = new google.maps.DirectionsRenderer({
    draggable: true,
    map,
    panel: document.getElementById("panel") as HTMLElement,
  });

  directionsRenderer.addListener("directions_changed", () => {
    const directions = directionsRenderer.getDirections();

    if (directions) {
      computeTotalDistance(directions);
    }
  });

  displayRoute(
    "Perth, WA",
    "Sydney, NSW",
    directionsService,
    directionsRenderer
  );
}

function displayRoute(
  origin: string,
  destination: string,
  service: google.maps.DirectionsService,
  display: google.maps.DirectionsRenderer
) {
  service
    .route({
      origin: origin,
      destination: destination,
      waypoints: [
        { location: "Adelaide, SA" },
        { location: "Broken Hill, NSW" },
      ],
      travelMode: google.maps.TravelMode.DRIVING,
      avoidTolls: true,
    })
    .then((result: google.maps.DirectionsResult) => {
      display.setDirections(result);
    })
    .catch((e) => {
      alert("Could not display directions due to: " + e);
    });
}

function computeTotalDistance(result: google.maps.DirectionsResult) {
  let total = 0;
  const myroute = result.routes[0];

  if (!myroute) {
    return;
  }

  for (let i = 0; i < myroute.legs.length; i++) {
    total += myroute.legs[i]!.distance!.value;
  }

  total = total / 1000;
  (document.getElementById("total") as HTMLElement).innerHTML = total + " km";
}

declare global {
  interface Window {
    initMap: () => void;
  }
}
window.initMap = initMap;
// [END maps_directions_draggable]
export {};