php 달력

<?php
function date_month(){
 $x=explode("-",$s);
 $nowY=date('Y');
 $nowM=date('m');
 $nowD=date('d');
 $start=date("t",mktime(0,0,0,$nowM,$nowD,$nowY));
 $end=date("N",mktime(0,0,0,$nowM,1,$nowY));
 $nowW=$end%7;
 $w=($start+$nowW)/7;
 $w=ceil($w);
 $w=$w-1;
 echo ("
  <table>
   <tr>
    <th colspan=7>".$nowY."년 ".$nowM."월</th>
   </tr>
   <tr>
    <th>일</th>
    <th>월</th>
    <th>화</th>
    <th>수</th>
    <th>목</th>
    <th>금</th>
    <th>토</th>
   </tr>
  ");

  for($r=0;$r<=$w;$r++){
   echo "<tr>";
    for($z=1;$z<=7;$z++){
     $startW=7*$r+$z;
     $startD=$startW-$nowW;
     if($startD<=0 || $startD>$start){
      echo "<td>&nbsp;</td>";
     }else{
      $s=date("Y-m-d",mktime(0,0,0,$nowM,$startD,$nowY));
      if( $s == date("Y-m-d") ){
       echo "<td>".$startD."</td>";
      }else{
       echo "<td class='now' >".$startD."</td>";
      }
     }
    }
   echo "</tr>";
  }
  echo "</table>";
 }
?>
<div><?php date_month(); ?></div>