
<?php
header('Content-Type: application/json');
function distanceMeters($lat1, $lon1, $lat2, $lon2) 
{
	$x = deg2rad( $lon1 - $lon2 ) * cos( deg2rad( $lat1 ) );
	$y = deg2rad( $lat1 - $lat2 );
	$dist = 6371000.0 * sqrt( $x*$x + $y*$y );

  return $dist;
}
	$db = file('db.txt');
	$sum_of_lat = 0;
	$sum_of_long = 0;
	$sum_of_time = 0;
	$array_time = array();
	$average = new stdClass;
	$average->latitude = 0;
	$average->longitude = 0;
	$average->inTime = 0;
	$average->parada = '';
	$db_size = count($db);	
	$distances=[];
	$paradas = array(
	        "Generales" => array(18.404916, -66.044828),
	        "Natu_1" => array(18.403663, -66.045529),
	        "Natu_2" => array(18.403769, -66.046572),
	        "Centro" => array( 18.403898, -66.048255),
	        "Biblio" => array(18.403994, -66.049781),
	        "Merenderos"  => array(18.406345, -66.050197),
	        "Leyes" => array (18.406069, -66.047733),
	        "Complejo" => array(18.406503, -66.046121),
	        "ROTC_Entrada" => array(18.406083, -66.043605),
	        "ROTC_Estacionamiento" => array( 18.407121, -66.042053)
	                );	
	for ($i = 0; $i < $db_size; $i++)
	{
		$decoded_location = json_decode($db[$i]);
		$sum_of_lat += $decoded_location->latitude;
		$sum_of_long += $decoded_location->longitude;
		array_push($array_time,$decoded_location->inTime);
		if($i+1 == $db_size)
		{
			$average->latitude = $sum_of_lat/$db_size;
			$average->longitude = $sum_of_long/$db_size;
			$average->inTime = date("h:i:s a",(array_sum(array_map('strtotime',$array_time)))/$db_size);			
		}
	}

	foreach($paradas as &$thing)
	{
		$plo = distanceMeters($average->latitude, $average->longitude, $thing[0], $thing[1]);
		array_push($distances,$plo);
		//echo $distances;

	}

	//echo $encoded_average;
	$indice = array_search(min($distances),$distances);
	$checking = array_keys($paradas);
	//$encoded_average = json_decode($encoded_avarage);
	
	$average->parada = $checking[$indice];
	$encoded_average =json_encode($average);
	echo $encoded_average;
	//echo "pol";
	//echo $average;
?>