PHP calendar: move the column of Sunday to the end

Question

This is the calendar script I got from an online tutorial. It works fine but I want to move the column of Sunday to the end (after the column of Saturday):

<?php
if (!isset($_REQUEST["month"])) $_REQUEST["month"] = date("n");
if (!isset($_REQUEST["year"]))  $_REQUEST["year"]  = date("Y");

$month_current = $_REQUEST["month"];
$year_current  = $_REQUEST["year"];

$prev_year = $year_current;
$next_year = $year_current;

$month_previous = $month_current-1;
$month_next = $month_current+1;

if ($month_previous == 0 ) 
{
 $month_previous = 12;
 $prev_year = $year_current - 1;
}

if ($month_next == 13 ) 
{
 $month_next = 1;
 $next_year = $year_current + 1;
}

$timestamp = mktime(0,0,0,$month_current,1,$year_current);
$lastdate    = date("t",$timestamp);

$thismonth = getdate ($timestamp);
$firstday  = $thismonth['wday'];
?>

<?php 
for ($i=0; $i<($lastdate + $firstday); $i++) 
{

 if(($i % 7) == 0 ) echo "<tr>\n";

 if($i < $firstday) echo "<td></td>\n";

 else echo "<td align='center' valign='middle' height='20px'>". ($i - $firstday + 1) . "</td>\n";

 if(($i % 7) == 6 ) echo "</tr>\n";

}
?>

I tried to change the code into this:

<?php 
for ($i=0; $i<($lastdate + $firstday); $i++) 
{

 if(($i % 7) == 1 ) echo "<tr>\n";

 # if $i less than the first day (1), don't print the value of $i
 if($i < $firstday) echo "<td></td>\n";

 # print the value of $i
 else echo "<td align='center' valign='middle' height='20px'>". ($i - $firstday + 1) . "</td>\n";

 if(($i % 7) == 0 ) echo "</tr>\n";

}
?>

It then does not display properly in the column when the first day starts from Sunday. For instance: http://ec-ener.eu/dump/index.php?month=8&year=2010

How can I fix it? Alternatively, how can I change the original script so that I can move Sunday to the end of the columns?

p.s. I also just found out that the original code seems to have a bit problem/ bug, if you check the html - tr and td - it generates,

<tr>
<td align='center' valign='middle' height='20px'>30</td>
<td align='center' valign='middle' height='20px'>31</td>


                              </table>
            </td>
        </tr>

it has the closing table in the and there is only a closing but no opening. I believe that the original single simple loop generates some invalid html! can I fix it?? thanks!

Answer 1

I think you need to change the firstday variable value for 1st day

$firstday  = $thismonth['wday']; //from here
//adding
$firstday = ($firstday + 6) % 7; //shifting the 1st day

Answer 2

There are two problems in your modified script:

The loop is starting from $i = 0, but not generating a <tr> tag until $i = 1. So the first column isn't in any <tr> tag.

Also, if($i < $firstday) needs to be true six times to generate six empty <td></td> tags to move the date to the right column.

To fix it, start the loop from 1, and when Sunday is the first day, set $firstday = 7

<?php 
if($firstday == 0 ) $firstday = 7;
for ($i=1; $i<($lastdate + $firstday); $i++) 
{

  if(($i % 7) == 1 ) echo "<tr>\n";

  # if $i less than the first day (1), don't print the value of $i
  if($i < $firstday) echo "<td></td>\n";

  # print the value of $i
  else echo "<td align='center' valign='middle' height='20px'>". ($i - $firstday + 1) . "</td>\n";

  if(($i % 7) == 0 ) echo "</tr>\n";

}
?>