From 44bf48e753f7ff7be1970dbd9c3bf6767a1745fc Mon Sep 17 00:00:00 2001
From: Gabor Hojtsy <goba@php.net>
Date: Mon, 16 Dec 2002 17:25:10 +0000
Subject: [PATCH] Introduce the limit for year values. Two years back is
 allowed for historical reasons, two years forward is allowed for those
 organizers who know two years in advance, what they will present...

This should make the cal page indexable by local search
engines too...
---
 cal.php | 51 +++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 43 insertions(+), 8 deletions(-)

diff --git a/cal.php b/cal.php
index cc8c029e4..3c944cc4f 100644
--- a/cal.php
+++ b/cal.php
@@ -17,6 +17,13 @@ $cy = isset($cy) ? (int) $cy : 0;
 $cm = isset($cm) ? (int) $cm : 0;
 $cd = isset($cd) ? (int) $cd : 0;
 
+// If the year is not valid, set it to the current year
+// This excludes all the "too old", or "too far in the future"
+// calendar to displays (so search engines can handle this page too)
+if ($cy != 0 && !valid_year($cy)) {
+    $cy = date("Y");
+}
+
 // We need to look up an event with an ID
 if ($id) {
     // Try to load event by ID and display header and info for that event
@@ -113,18 +120,27 @@ if (count($errors) > 0) {
 $bom = mktime(0, 0, 1, $cm,   1, $cy);
 $eom = mktime(0, 0, 1, $cm+1, 0, $cy);
 
-// Last month and next month
+// Link to previous month (but do not link to too early dates)
 $lm = mktime(0, 0, 1, $cm, 0, $cy);
+if (valid_year(date("Y", $lm))) {
+   $prev_link = '<a href="' . $PHP_SELF . strftime('?cm=%m&amp;cy=%Y">%B, %Y</a>', $lm);
+} else {
+   $prev_link = '&nbsp;';
+}
+
+// Link to next month (but do not link to too early dates)
 $nm = mktime(0, 0, 1, $cm+1, 1, $cy);
+if (valid_year(date("Y", $nm))) {
+   $next_link = '<a href="' . $PHP_SELF . strftime('?cm=%m&amp;cy=%Y">%B, %Y</a>', $nm);
+} else {
+   $next_link = '&nbsp;';
+}
 
 // Print out navigation links for previous and next month
 echo '<br /><table bgcolor="#d0d0d0" width="100%" border="0" cellspacing="0" cellpadding="3">',
-     "\n<tr>", '<td align="left" width="33%"><a href="', $PHP_SELF,
-     strftime('?cm=%m&amp;cy=%Y">%B, %Y</a></td>', $lm),
+     "\n<tr>", '<td align="left" width="33%">', $prev_link, '</td>', 
      '<td align="center" width="33%">', strftime('<b>%B, %Y</b></td>', $bom),
-     '<td align="right" width="33%"><a href="', $PHP_SELF,
-     strftime('?cm=%m&amp;cy=%Y">%B, %Y</a></td>', $nm),
-     "</tr>\n</table>\n";
+     '<td align="right" width="33%">', $next_link, "</td></tr>\n</table>\n";
 
 // Begin the calendar table
 echo '<table id="cal" bgcolor="#f0f0f0" width="100%" border="1" cellspacing="0" cellpadding="3">',
@@ -168,7 +184,8 @@ commonFooter();
 
 // Generate the date on which a recurring event falls for a given month
 // $bom and $eom are the first and last day of the month to look at
-function date_for_recur($recur, $day, $bom, $eom) {
+function date_for_recur($recur, $day, $bom, $eom)
+{
 
     // $day == 1 == 'Sunday' == date("w",'some sunday')+1
   
@@ -188,7 +205,8 @@ function date_for_recur($recur, $day, $bom, $eom) {
 }
 
 // Display a <div> for each of the events that are on a given day
-function display_events_for_day($day, $events) {
+function display_events_for_day($day, $events)
+{
     
     // For preservation of state in the links
     global $PHP_SELF, $cm, $cy;
@@ -330,4 +348,21 @@ function read_event($fp)
     );
 }
 
+// We would not like to allow any year to be viewed, because
+// it would fool some [not clever enough] search engines
+function valid_year($year)
+{
+    // Get current year and compare to one sent in
+    $current_year = date("Y");
+    
+    // We only allow two years back (for historical reasons) and two
+    // years forth (to plan your schedule for the next year)
+    if (($year < $current_year - 2) || ($year > $current_year + 2)) {
+        return FALSE;
+    }
+    
+    // The year is all right
+    return TRUE;
+}
+
 ?>