Restore recurrence computation code to a version before the refactoring for libkolab bindings

1 files changed, 84 insertions, 29 deletions

diff --git a/plugins/libkolab/lib/kolab_date_recurrence.php b/plugins/libkolab/lib/kolab_date_recurrence.php
index 3aaa399..9eeeca1 100644
--- a/plugins/libkolab/lib/kolab_date_recurrence.php
+++ b/plugins/libkolab/lib/kolab_date_recurrence.php
@@ -3,8 +3,7 @@
 /**
  * Recurrence computation class for xcal-based Kolab format objects
  *
- * Utility class to compute instances of recurring events.
- * It requires the libcalendaring PHP module to be installed and loaded.
+ * Uitility class to compute instances of recurring events.
  *
  * @version @package_version@
  * @author Thomas Bruederli <bruederli@kolabsys.com>
@@ -26,31 +25,43 @@
  */
 class kolab_date_recurrence
 {
-    private /* EventCal */ $engine;
-    private /* kolab_format_xcal */ $object;
-    private /* DateTime */ $start;
-    private /* DateTime */ $next;
-    private /* cDateTime */ $cnext;
-    private /* DateInterval */ $duration;
+    private $engine;
+    private $object;
+    private $next;
+    private $duration;
+    private $tz_offset = 0;
+    private $dst_start = 0;
+    private $allday = false;
+    private $hour = 0;
 
     /**
      * Default constructor
      *
      * @param array The Kolab object to operate on
      */
-    function __construct($object)
+    function __construct($event)
     {
-        $data = $object->to_array();
+        $this->object = $object = $event->to_array();
+        $this->next = new Horde_Date($object['start'], kolab_format::$timezone->getName());
 
-        $this->object = $object;
-        $this->engine = $object->to_libcal();
-        $this->start = $this->next = $data['start'];
-        $this->cnext = kolab_format::get_datetime($this->next);
-
-        if (is_object($data['start']) && is_object($data['end']))
-            $this->duration = $data['start']->diff($data['end']);
+        if (is_object($object['start']) && is_object($object['end']))
+            $this->duration = $object['start']->diff($object['end']);
         else
-            $this->duration = new DateInterval('PT' . ($data['end'] - $data['start']) . 'S');
+            $this->duration = new DateInterval('PT' . ($object['end'] - $object['start']) . 'S');
+
+        // use (copied) Horde classes to compute recurring instances
+        // TODO: replace with something that has less than 6'000 lines of code
+        $this->engine = new Horde_Date_Recurrence($this->next);
+        $this->engine->fromRRule20($this->to_rrule($object['recurrence']));  // TODO: get that string directly from libkolabxml
+
+        foreach ((array)$object['recurrence']['EXDATE'] as $exdate)
+            $this->engine->addException($exdate->format('Y'), $exdate->format('n'), $exdate->format('j'));
+
+        $now = new DateTime('now', kolab_format::$timezone);
+        $this->tz_offset = $object['allday'] ? $now->getOffset() - date('Z') : 0;
+        $this->dst_start = $this->next->format('I');
+        $this->allday = $object['allday'];
+        $this->hour = $this->next->hour;
     }
 
     /**
@@ -62,14 +73,20 @@ class kolab_date_recurrence
     public function next_start($timestamp = false)
     {
         $time = false;
-
-        if ($this->engine && $this->next) {
-            if (($cnext = new cDateTime($this->engine->getNextOccurence($this->cnext))) && $cnext->isValid()) {
-                $next = kolab_format::php_datetime($cnext);
-                $time = $timestamp ? $next->format('U') : $next;
-                $this->cnext = $cnext;
-                $this->next = $next;
+        if ($this->next && ($next = $this->engine->nextActiveRecurrence(array('year' => $this->next->year, 'month' => $this->next->month, 'mday' => $this->next->mday + 1, 'hour' => $this->next->hour, 'min' => $this->next->min, 'sec' => $this->next->sec)))) {
+            if ($this->allday) {
+                $next->hour = $this->hour;  # fix time for all-day events
+                $next->min = 0;
+            }
+            if ($timestamp) {
+                # consider difference in daylight saving between base event and recurring instance
+                $dst_diff = ($this->dst_start - $next->format('I')) * 3600;
+                $time = $next->timestamp() - $this->tz_offset - $dst_diff;
             }
+            else {
+                $time = $next->toDateTime();
+            }
+            $this->next = $next;
         }
 
         return $time;
@@ -86,7 +103,7 @@ class kolab_date_recurrence
             $next_end = clone $next_start;
             $next_end->add($this->duration);
 
-            $next = $this->object->to_array();
+            $next = $this->object;
             $next['recurrence_id'] = $next_start->format('Y-m-d');
             $next['start'] = $next_start;
             $next['end'] = $next_end;
@@ -106,11 +123,49 @@ class kolab_date_recurrence
      */
     public function end($limit = 'now +1 year')
     {
-        $limit_dt = new DateTime($limit);
-        if ($this->engine && ($cend = $this->engine->getLastOccurrence()) && ($end_dt = kolab_format::php_datetime(new cDateTime($cend))) && $end_dt < $limit_dt) {
-            return $end_dt->format('U');
+        if ($this->object['recurrence']['UNTIL'])
+            return $this->object['recurrence']['UNTIL']->format('U');
+
+        $limit_time = strtotime($limit);
+        while ($next_start = $this->next_start(true)) {
+            if ($next_start > $limit_time)
+                break;
+        }
+
+        if ($this->next) {
+            $next_end = $this->next->toDateTime();
+            $next_end->add($this->duration);
+            return $next_end->format('U');
         }
 
         return false;
     }
+
+    /**
+     * Convert the internal structured data into a vcalendar RRULE 2.0 string
+     */
+    private function to_rrule($recurrence)
+    {
+      if (is_string($recurrence))
+          return $recurrence;
+
+        $rrule = '';
+        foreach ((array)$recurrence as $k => $val) {
+            $k = strtoupper($k);
+            switch ($k) {
+            case 'UNTIL':
+                $val = $val->format('Ymd\THis');
+                break;
+            case 'EXDATE':
+                foreach ((array)$val as $i => $ex)
+                    $val[$i] = $ex->format('Ymd\THis');
+                $val = join(',', (array)$val);
+                break;
+            }
+            $rrule .= $k . '=' . $val . ';';
+        }
+
+      return $rrule;
+    }
+
 }