calculate-distance-between-coordinates/lib/index.js

Calculate the distance between coordinates

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.getTotalDistance = exports.getDistanceBetweenTwoPoints = void 0;
// source of algorithm: https://www.geodatasource.com/developers/javascript
function getDistanceBetweenTwoPoints(cord1, cord2, unit) {
    if (unit === void 0) { unit = 'km'; }
    if (cord1.lat === cord2.lat && cord1.lon === cord2.lon) {
        return 0;
    }
    var radlat1 = (Math.PI * cord1.lat) / 180;
    var radlat2 = (Math.PI * cord2.lat) / 180;
    var theta = cord1.lon - cord2.lon;
    var radtheta = (Math.PI * theta) / 180;
    var dist = Math.sin(radlat1) * Math.sin(radlat2) +
        Math.cos(radlat1) * Math.cos(radlat2) * Math.cos(radtheta);
    if (dist > 1) {
        dist = 1;
    }
    dist = Math.acos(dist);
    dist = (dist * 180) / Math.PI;
    dist = dist * 60 * 1.1515;
    if (unit === 'km') {
        dist = dist * 1.609344;
    }
    return dist;
}
exports.getDistanceBetweenTwoPoints = getDistanceBetweenTwoPoints;
function getTotalDistance(coordinates, unit) {
    if (unit === void 0) { unit = 'km'; }
    coordinates = coordinates.filter(function (cord) {
        if (cord.lat && cord.lon) {
            return true;
        }
    });
    var totalDistance = 0;
    if (!coordinates) {
        return 0;
    }
    if (coordinates.length < 2) {
        return 0;
    }
    for (var i = 0; i < coordinates.length - 2; i++) {
        if (!coordinates[i].lon ||
            !coordinates[i].lat ||
            !coordinates[i + 1].lon ||
            !coordinates[i + 1].lat) {
            totalDistance = totalDistance;
        }
        totalDistance =
            totalDistance +
                getDistanceBetweenTwoPoints(coordinates[i], coordinates[i + 1], unit);
    }
    return totalDistance.toFixed(2);
}
exports.getTotalDistance = getTotalDistance;