utils.js

"use strict";

import typechecked from "https://gustavlindberg99.github.io/Typecheck.js/min/typecheck-v1.min.js";
import {Multiline, Point, Segment} from "https://unpkg.com/@flatten-js/core@1.4.8/dist/main.mjs";
typechecked.add(Multiline, Point, Segment);

/**
 * Checks if the current device is a mobile device by looking at the user agent.
 *
 * @return True if the device is mobile, false otherwise.
 */
export function deviceIsMobile() /*: Boolean */ {
    const userAgent = (navigator.userAgent || navigator.vendor || window.opera);
    return userAgent != undefined && (
        /(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|mobile.+firefox|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows ce|xda|xiino/i.test(userAgent)
        || /1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test(userAgent.substr(0, 4))
    );
}
deviceIsMobile = typechecked(deviceIsMobile);

/**
 * Creates a multiline from an array of points.
 *
 * @param points    The points to use as vertices for the multiline.
 *
 * @return A multiline with only segments.
 */
export function multilineFromPoints(points /*: Array<Point> */) /*: Multiline */ {
    if(points.length < 2){
        throw new TypeError("Can't create a multiline from fewer than two points");
    }

    const segments = [];
    for(let i = 0; i < points.length - 1; i++){
        segments.push(new Segment(points[i], points[i + 1]));
    }
    return new Multiline(segments);
}
multilineFromPoints = typechecked(multilineFromPoints);

/**
 * Gets the date of easter for the given year (source: https://gist.github.com/johndyer/0dffbdd98c2046f41180c051f378f343).
 *
 * @param year  The year to get easter in.
 *
 * @return A Date object with the easter date for that year.
 */
export function getEaster(year /*: Number */) /*: Date */ {
    const g = year % 19;
    const c = Math.floor(year / 100);
    const h = (c - Math.floor(c / 4) - Math.floor((8 * c + 13) / 25) + 19 * g + 15) % 30;
    const i = h - Math.floor(h/28) * (1 - Math.floor(29 / (h + 1)) * Math.floor((21 - g) / 11));
    const j = (year + Math.floor(year / 4) + i + 2 - c + Math.floor(c / 4)) % 7;
    const l = i - j;
    const month = 3 + Math.floor((l + 40)/44);
    const day = l + 28 - 31 * Math.floor(month / 4);
    return new Date(Date.UTC(year, month - 1, day, 2));
}
getEaster = typechecked(getEaster);