PHP Time Ago Function

<?php
function time_ago($datetime, $full = false) {
	$now = new DateTime();
	$ago = new DateTime($datetime);
	$diff = $now->diff($ago);

	$ar = [];
	foreach ($diff as $key => $value) {
		$ar[$key] = $value;
	}

	$x = floor($diff->d / 7);
	$ar['w'] = $x;
	$ar['d'] -= $x * 7;

	$d_string = [
		'y' => 'year',
		'm' => 'month',
		'w' => 'week',
		'd' => 'day',
		'h' => 'hour',
		'i' => 'minute',
		's' => 'second',
	];

	foreach ($d_string as $key => &$val) {
		if ($ar[$key]) {
			$val = $ar[$key] . ' ' . $val . ($ar[$key] > 1 ? 's' : '');
		} else {
			unset($d_string[$key]);
		}
	}

	if (!$full) {
		$d_string = array_slice($d_string, 0, 1);
	}
	return $d_string ? implode(', ', $d_string) . ' ago' : 'just now';
}
?>

<?php

echo time_ago('2020-04-19 11:38:43'); 
// 4 months

echo time_ago('2020-04-19 11:38:43', true); 
//4 months, 1 week, 4 days, 23 hours, 5 minutes, 19 seconds

echo time_ago('2010-10-20'); // 9 years

echo time_ago('2010-10-20', true); 
//9 years, 10 months, 1 week, 4 days, 10 hours, 45 minutes, 32 seconds

//timestamp 
echo time_ago('@1598867187'); // 19 seconds

echo time_ago('@1598867187', true); //19 seconds

// html
$join_date = '2020-04-19 11:38:43';
echo '<div title="'.$join_date.'">'.time_ago($join_date).'</div>';

?>