flaglib/lib/LatLon.js

Ignition event 15 added.

var util = require('util');

var Util = require('./util.js');
var logger = require('./logger');

module.exports = LatLon;

var LATITUDE = "1";
var LONGITUDE = "2";
var NAME = "3";

var utility = new Util();


function LatLon(lat,lon, pointName) {
	this.latitude = null; 
	this.longitude = null;
	this.name = null;
	this.invalid = false;
	
	this.latitude = lat;
	this.longitude = lon;
	
	this.name  = pointName;
	
}

LatLon.prototype.getLat = function(){
	return this.latitude;
}

LatLon.prototype.getLon = function(){
	return this.longitude;
}

LatLon.prototype.getName = function(){
	return this.name;
}

/*
 * This function compare distance between pickup point and current location.
 */

LatLon.prototype.checkDistance = function(currenLoc){
	
	var distance = -1;

	if ((currenLoc == null) || (this.latitude == null)||(this.longitude == null) || (this.latitude == 0)||(this.longitude == 0) 
		|| (currenLoc.getLat() == 0)||(currenLoc.getLon() == 0) || (currenLoc.getLat() == null)||(currenLoc.getLon()== null)){
		
		return distance;
	}
	var lat1 = this.latitude;
	var lat2 = currenLoc.getLat();
	var lon1 = this.longitude;
	var lon2 = currenLoc.getLon();
	
	var p = 0.017453292519943295;    // Math.PI / 180
	var c = Math.cos;
	var a = 0.5 - c((lat2 - lat1) * p)/2 + 
	          c(lat1 * p) * c(lat2 * p) * 
	          (1 - c((lon2 - lon1) * p))/2;

	  distance = 12742 * Math.asin(Math.sqrt(a)); // 2 * R; R = 6371 km
	 
	  
	return distance; 
}

/*
 * This function compare distance between pickup point and current location.
 * returns distance in km.
 */

function checkDistance(currenLoc){
	var distance = -1;

	if ((currenLoc == null) || (this.latitude == null)||(this.longitude == null) || (this.latitude == 0)||(this.longitude == 0) 
		|| (currenLoc.getLat() == 0)||(currenLoc.getLon() == 0) || (currenLoc.getLat() == null)||(currenLoc.getLon()== null)){
		
		return distance;
	}
	var lat1 = this.latitude;
	var lat2 = currenLoc.getLat();
	var lon1 = this.longitude;
	var lon2 = currenLoc.getLon();
	
	var p = 0.017453292519943295;    // Math.PI / 180
	var c = Math.cos;
	var a = 0.5 - c((lat2 - lat1) * p)/2 + 
	          c(lat1 * p) * c(lat2 * p) * 
	          (1 - c((lon2 - lon1) * p))/2;

	  distance = 12742 * Math.asin(Math.sqrt(a)); // 2 * R; R = 6371 km
	 
	  
	return distance; 
}

/*
 * This function compare distance between pickup point and current location, and calculates the time 
 *  to reach the pickup point.
 */

LatLon.prototype.checkTimeToPoint = function(currenLoc,speed){
	var time = -1;
	if (speed == 0){
		speed = 1;
	}
	if ((currenLoc == null) || (this.latitude == null)||(this.longitude == null)){
		return -1;
	}
	
	//distance in 
	/*
	 * Use driving distance rather straight line distance
	 * https://www.npmjs.com/package/google-distance
	 */
	
	var distance = this.checkDistance(currenLoc);
	if (distance == -1){
		return time;
	}
	
	/*
	totaltime = totaltime/1000;
	var avgSpeed = (totaldist*1000)/totaltime;
	
	var speed2 = speed * 3.6;
	*/
	
	time = distance/speed;
	//time = time/60; //convert to minutes.
	
	//if time is greaterthan alert before time, return -1.
	/*if (alertBefore<time){
		time = -1;
	}*/
	
	return time*60; //in minutes 
	
}

LatLon.prototype.isInValid = function(){
	return this.invalid;
}

LatLon.prototype.injectData = function(lat,lon, pointName){
	this.latitude = lat;
	this.longitude = lon;
	this.name  = pointName;

}


/*
 * Parse JSON obejct and create objects
 */

LatLon.prototype.fromJSON = function(data){
	
	if (data == null){
		this.invalid = true;
		return;
	}
	
	var flagJson = null;
	
	flagJson = JSON.parse(utility.hex2a(data));
	
	this.latitude = flagJson[LATITUDE];
	this.longitude = flagJson[LONGITUDE];
	this.name = flagJson[NAME];
	
}


/*
 * Parse it to JSON to store
 */
LatLon.prototype.toJSON = function(){
		
	var mainObj = {};
	
	mainObj[LATITUDE] = this.latitude;
	mainObj[LONGITUDE] = this.longitude;
	mainObj[NAME] = this.name;
	return utility.convertFromAscii2Hexa(JSON.stringify(mainObj));
	
}