From 3cdc35b44d6489116ddbe7ac8e8080b994402235 Mon Sep 17 00:00:00 2001
From: Adrian Greeve <adrian@moodle.com>
Date: Tue, 9 Aug 2016 11:18:40 +0800
Subject: [PATCH] MDL-22183 lib: Cleanup of get_next functions.

---
 lib/statslib.php | 33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/lib/statslib.php b/lib/statslib.php
index 043b54cb659..a414faed00f 100644
--- a/lib/statslib.php
+++ b/lib/statslib.php
@@ -1024,13 +1024,10 @@ function stats_get_base_monthly($time=0) {
  */
 function stats_get_next_day_start($time) {
     $next = stats_get_base_daily($time);
-    $next = $next + 60*60*26;
-    $next = stats_get_base_daily($next);
-    if ($next <= $time) {
-        //DST trouble - prevent infinite loops
-        $next = $next + 60*60*24;
-    }
-    return $next;
+    $nextdate = new DateTime();
+    $nextdate->setTimestamp($next);
+    $nextdate->add(new DateInterval('P1D'));
+    return $nextdate->getTimestamp();
 }
 
 /**
@@ -1040,13 +1037,10 @@ function stats_get_next_day_start($time) {
  */
 function stats_get_next_week_start($time) {
     $next = stats_get_base_weekly($time);
-    $next = $next + 60*60*24*9;
-    $next = stats_get_base_weekly($next);
-    if ($next <= $time) {
-        //DST trouble - prevent infinite loops
-        $next = $next + 60*60*24*7;
-    }
-    return $next;
+    $nextdate = new DateTime();
+    $nextdate->setTimestamp($next);
+    $nextdate->add(new DateInterval('P1W'));
+    return $nextdate->getTimestamp();
 }
 
 /**
@@ -1056,13 +1050,10 @@ function stats_get_next_week_start($time) {
  */
 function stats_get_next_month_start($time) {
     $next = stats_get_base_monthly($time);
-    $next = $next + 60*60*24*33;
-    $next = stats_get_base_monthly($next);
-    if ($next <= $time) {
-        //DST trouble - prevent infinite loops
-        $next = $next + 60*60*24*31;
-    }
-    return $next;
+    $nextdate = new DateTime();
+    $nextdate->setTimestamp($next);
+    $nextdate->add(new DateInterval('P1M'));
+    return $nextdate->getTimestamp();
 }
 
 /**