// Load dependencies
const { TimerMgr } = require('../utils');
const tm = new TimerMgr();

function debounceFunction(id, debounceTimeout, func, params) {
    console.warn('debounce', id, debounceTimeout);

    timeout = time.ZonedDateTime.now().plusNanos(debounceTimeout * 1000000);
    
    if (tm.hasTimer(id) && tm.isActive(id)) {
        log.info(`Skip evaluation of function with id ${id} as function is already running. Reschedule timer`);
        tm.reschedule(id, timeout);
    } else {
        log.info(`Create timer to execute function ${id}`);
        if (tm.hasTimer(id)) {
            tm.cancel(id);
        }
        tm.create(id, timeout, func, params);
    }
}

function distanceBetween(locationA, locationB) {
    const [lat1, lon1] = locationA.split(',').map(Number);
    const [lat2, lon2] = locationB.split(',').map(Number);

    const toRadians = (degree) => degree * (Math.PI / 180);
    
    const radLat1 = toRadians(lat1);
    const radLon1 = toRadians(lon1);
    const radLat2 = toRadians(lat2);
    const radLon2 = toRadians(lon2);
    
    if (lat1 === lat2 && lon1 === lon2) return '0 m';

    const dlon = radLon2 - radLon1;
    const dlat = radLat2 - radLat1;

    const a = Math.pow(Math.sin(dlat / 2), 2)
            + Math.cos(radLat1) * Math.cos(radLat2)
            * Math.pow(Math.sin(dlon / 2), 2);
  
    const c = 2 * Math.asin(Math.sqrt(a));
    const r = 6371000; // Radius of earth in meters

    return `${(c * r).toFixed()} m`;
}

module.exports = {
    debounceFunction,
    distanceBetween
};