Days and Dates Calculation Functions

day_between_dates_and_utilities.inc.php

//pass the function the MySQL standardized date and retreive a date relative to wordpress GMT and wordpress date and time display options
if(!function_exists('sm_display_date')) { function sm_display_date($mysqldate) {
	$display_date = date_i18n( get_option('date_format').' '.get_option('time_format'),strtotime($mysqldate), get_option('gmt_offset') );
	return $display_date;
}}

//pass the function a UNIX TIMESTAMP or "Properly Formated Date/Time" and retreive a date formated for MySQL database date field type 
//optionally pass a number of days to return a time XX days before or after the date/time sent
if(!function_exists('sm_mysql_date')) { function sm_mysql_date($time, $days = 0) {
	$seconds = 60*60*24*$days;
	$unix_time = strtotime($time)+$seconds;
	$mysqldate = date( 'Y-m-d H:i:s', $unix_time);
	return $mysqldate;
}}

if(!function_exists('sm_seconds_to_days')) { function sm_seconds_to_days($seconds) {
	return ($seconds / 24 / 60 / 60);
}}

if(!function_exists('sm_days_between_dates')) { function sm_days_between_dates($date1, $date2 = '', $precision = '1') {
	if (empty($date2)) 
	    $date2 = current_time('mysql');

	//setup the times based on string dates, if dates are not strings return false.
	if ( is_string($date1) ) 
	    $date1 = strtotime($date1);
	else 
	    return false;
	    
	if ( is_string($date2) ) 
	    $date2 = strtotime($date2);
	else 
	    return false;

	$days = round( sm_seconds_to_days($date1 - $date2), $precision );
	return $days;
}}


// convert date
if(!function_exists('convert_date')) { function convert_date($thedate, $format='') {
	if($format =='')
		$format = "m/d/Y";
	
	if($thedate != '')
		return date($format, strtotime($thedate));
	else
		return $thedate;
			
}}