geographic-coordinate-converter/coordinate-converter.js

Geographic latitude longitude coordinate format converter

import {
	decimalPositionToDegreeMinutesSecondsString,
	decimalPositionToDegreeString,
	degreeLatToDecimal,
	degreeLngToDecimal,
	degreeMinutesSecondsLatToDecimal,
	degreeMinutesSecondsLngToDecimal
} from "./utils";

class GeographicCoordinateConverterBuilder {

	/***
	 * Return a converter instance from an array of coordinates or from a string
	 * @param coordinate string|array
	 * @returns {GeographicCoordinateConverter}
	 */
	fromDecimal(coordinate) {
		if (Array.isArray(coordinate)) {
			return new GeographicCoordinateConverter(coordinate[0], coordinate[1]);
		} else {
			const latlng = coordinate.split(" ");
			return new GeographicCoordinateConverter(Number.parseFloat(latlng[0]), Number.parseFloat(latlng[1]));
		}
	}

	/**
	 * Return a converter instance from a degree coordinate string
	 * @param coordinate string
	 * @returns {GeographicCoordinateConverter}
	 */
	fromDegreeMinutes(coordinate) {
		const slicePoint = Math.max(coordinate.indexOf('s'), coordinate.indexOf('S'), coordinate.indexOf('n'), coordinate.indexOf('N'));
		let latDecimal = coordinate.slice(0, slicePoint + 1).replace(/\s/g,'');
		let lngDecimal = coordinate.slice(slicePoint + 2).replace(/\s/g,'');
		return new GeographicCoordinateConverter(degreeLatToDecimal(latDecimal), degreeLngToDecimal(lngDecimal));
	}

	/**
	 * Return a converter instance from a degree minutes seconds coordinate string
	 * @param coordinate string
	 * @returns {GeographicCoordinateConverter}
	 */
	fromDegreeMinutesSeconds(coordinate) {
		const slicePoint = Math.max(coordinate.indexOf('s'), coordinate.indexOf('S'), coordinate.indexOf('n'), coordinate.indexOf('N'));
		let latDecimal = coordinate.slice(0, slicePoint + 1).replace(/\s/g,'');
		let lngDecimal = coordinate.slice(slicePoint + 2).replace(/\s/g,'');
		return new GeographicCoordinateConverter(degreeMinutesSecondsLatToDecimal(latDecimal), degreeMinutesSecondsLngToDecimal(lngDecimal));
	}
}

export const CoordinateConverter = new GeographicCoordinateConverterBuilder();

export class GeographicCoordinateConverter {
	constructor(lat, lng) {
		this.lat = lat;
		this.lng = lng;
	}

	/**
	 * Returns a string in decimal format
	 * @returns {string}
	 */
	toDecimal() {
		return `${this.lat} ${this.lng}`;
	}

	/**
	 * Returns a array of latitude longitude
	 * @returns {*[]}
	 */
	toDecimalArray() {
		return [this.lat, this.lng];
	}

	/**
	 * Returns a string in degree format
	 * @returns {*}
	 */
	toDegreeMinutes() {
		return decimalPositionToDegreeString(this.lat, this.lng);
	}

	/**
	 * Returns a string in decimal minutes seconds format
	 * @returns {*}
	 */
	toDegreeMinutesSeconds() {
		return decimalPositionToDegreeMinutesSecondsString(this.lat, this.lng);
	}
}