<?
$week number = 1;//the for loop increment number 
$week cycle = 2;//This will provide the date for the 1st, 2nd, 3rd or 4th week of the month.
$start_date = "2008-02-01";
 
 
$nw = ($week number * $week cycle) + 1;//+ 1 to be in the next range	
 
$next_start = date("Y-m-d",strtotime("+$nw week", $start_date));
$next_end = date('Y-m-d',strtotime("+1 week", $next_start))."<br>";
$week_number = date('W', $next_start);//week number of the year
?>

<?php
 
$increment = 1;		//  # of weeks to increment by
 
//  First day of the first week of the year
$startdate = strtotime("31 December 2007");
 
//  $all_weeks[1] is the first partial week of the year
//  $all_weeks[53] is the last partial week of the year
$all_weeks = array();
 
for ($week = 0; $week <= 52; $week += $increment)
{
  $week_data = array();
 
  $week_data['start'] = strtotime("+$week weeks", $startdate);
  $week_data['end'] = strtotime("+6 days", $week_data['start']);
 
  $all_weeks[$week + 1] = $week_data;
}
 
echo "<pre>";
echo "Week No.	Start Date	End Date\r\n";
 
foreach ($all_weeks as $week => $week_data)
{
  echo $week . "\t\t" . date("Y-m-d", $week_data['start']) . 
	"\t" . date("Y-m-d", $week_data['end']) . "\r\n";
}
 
echo "</pre>"
 
?>

 
<?
 
$max_week = '3';
$start_date = '2008-01-01';
$end_date = '2008-01-31';
 
/**-------------loop through number of weeks------------**/
for($i = 1; $i <= $max_week; $i++)
   {
       	//format to two characters
	$week_num = "0$i";
 
       	//detemine start date interval 
	 if($i == 1)
       	   {
       		$start_date = $start_date;//week 1
	   }
	  else
	     {
        	//week 2, 3 and 4	
		$wk_start = strtotime($start_date);
		$start_date = date("Y-m-d", strtotime("+7 days", $wk_start));
	     }
 
 
	   //flush previous array contents
	   unset ($group_seg);
 
	   /**------------get group module data to apply to schedule------------**/
	   $query = "SELECT distinct(s.seg_id) w.group_id,
	             	    s.time_from, s.time_to, w.weekday
		     FROM group_week w, day_segment s
		     WHERE s.model_id = w.model_id
		     AND w.group_id = '$group_id'";
 
	   $result = mysqli_query ($mysqli, $query);
	   while($row = mysqli_fetch_array($result))
		{
 		   $group_seg[] = $row;
		}
 
 
    	   /**------------------- event type info to insert-----------------------**/ 
  	   //loop through segment start and end time
	   foreach($group_seg as $group_segment)
		{
	 	   //database stored time from daily model segments
		   $start_time = $group_segment['time_from'];
		   $end_time = $group_segment['time_to'];
		   $group_id = $group_segment['group_id'];
		   $day = $group_segment['weekday'];
 
		   //more than one week cycle used interval date
		   if($max_week > 1)
			{
 
			     //determine date start incrementation using max_week
			    switch($max_week)
    			    	{
            			   case '1': //1 week
            			      $cycle_days = 7;
             			   break;
           		    	   case '2': //2 weeks
           		    	      $cycle_days = 14;
              			   break;
           			   case '3': //3 weeks
           			       $cycle_days = 21;
             			   break;
           			   case '4': //4 weeks
           			       $cycle_days = 28;
            			   break;
            			}
 
                             /**----------increment using $cycle_days from above--------**/      
                             for($f = $start_date; $f <= $end_date; $f = date("Y-m-d", strtotime($f . "+ $cycle_days day")))
		                {
			   	   //set start date
  			   	   $startdate = strtotime($f);
   			           $type_start_date = date("Y-m-d", $startdate);
 
			           //set end date with addtional 6 days
			          $wk_start = strtotime($type_start_date);
		     	          $wk_end_date = date("Y-m-d", strtotime("+6 days", $wk_start));
 
			          //check incremented end date does not exceed selected end date
			          if($wk_end_date <= $end_date)	
			   	     {
				        $type_end_date = $wk_end_date;//incremented end date
				     }
				    else
				       {
					   $type_end_date = $end_date;//selected end date
				       }
 
 
                                   /**INSERT STATEMENT GOES HERE**/									}
			 }
			 else
			    {
				// single week cycle insert selected start and end dates no manipulation needed
				$type_start_date = $start_date;
				$type_end_date = $end_date;
 
		  		/**INSERT STATEMENT GOES HERE**/
			    }
		     }//foreach	
	    	}//for
 
    ?>