From c9ab0686426cfe0161ee20a718c1f172a7809728 Mon Sep 17 00:00:00 2001
From: Bart Van Der Meerssche <bart.vandermeerssche@flukso.net>
Date: Tue, 15 Sep 2009 19:46:26 +0000
Subject: [PATCH] web: backport the handling of timezones for night.rrd to
 xmlrpc alpha API

---
 web/drupal/modules/logger/xmlrpc.inc  | 24 ++++++++++++++++++------
 web/drupal/modules/logger/xmlrpc1.inc |  2 +-
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/web/drupal/modules/logger/xmlrpc.inc b/web/drupal/modules/logger/xmlrpc.inc
index a2a4229..54f5f38 100644
--- a/web/drupal/modules/logger/xmlrpc.inc
+++ b/web/drupal/modules/logger/xmlrpc.inc
@@ -2,7 +2,7 @@
 
 //
 // xmlrpc.inc : data and management plane xmlrpc methods for logging metering data
-//              aplha version API
+//              alpha version API
 //
 // Copyright (c) 2008-2009 jokamajo.org
 //
@@ -77,11 +77,11 @@ function _logger_measurement_add($logs) {
       }
       system($command, $return);
       if ($return == 0) {
-        // update the night rrd every day at 6AM UTC
+        // update the night rrd every day at 6AM local time
         if (time() > $meterdata->night) {
-          $timestamp = floor(time()/86400)*86400;
-          $start = $timestamp + 3600;
-          $end = $start + 10800; //3h time interval
+          $midnight = _logger_midnight(time(), $auth['device']);
+          $start = $midnight + 7200; // 2AM local time
+          $end = $start + 10800; // 3h time interval
           $command = $path->root ."/rrdtool fetch ". $path->base . $meter .".rrd AVERAGE -r 900 -s ". $start ." -e ". $end ." | tail -n 12 | awk -F': ' '{SUM += $2} END {print SUM/12}'";
           $night = (float)shell_exec($command); //test shell_exec iso system
           $command = $path->root .'/rrdtool update '. $path->night . $meter .'.rrd '. $timestamp .':'. $night;
@@ -92,7 +92,7 @@ function _logger_measurement_add($logs) {
           else {
             watchdog_xmlrpc('logger.measurementAdd', 'error updating night rrd: %command', array('%command' => $command), WATCHDOG_ERROR); //debugging
           }
-          $meterdata->night = $timestamp + 104400; //add an offset of 29h, i.e. 5AM UTC next day
+          $meterdata->night = $midnight + 108000; //add an offset of 30h = 6AM local time
         }
         // {logger_meters} is updated with the true metervalue $value, NOT $value*$meterdata->factor since we're not normalising this entry!
         db_query("UPDATE {logger_meters} SET access = %d, night = %d, value = %d WHERE meter = '%s'", time(), $meterdata->night, $value, $meter);
@@ -104,3 +104,15 @@ function _logger_measurement_add($logs) {
   }
   return $command; //using $command for testing purposes, replace by $info afterwards
 }
+
+/**
+ * Calculate the most recent midnight for this device based on the user's timezone
+ */
+function _logger_midnight($timestamp, $device) {
+  $timezone = db_result(db_query("SELECT u.timezone FROM {logger_devices} ld INNER JOIN {users} u ON ld.uid = u.uid WHERE ld.device = '%s'", $device));
+  // add one day to make sure $midnight > $timestamp
+  $midnight = floor($timestamp/86400 + 1)*86400 - $timezone;
+  // search for first $midnight < $timestamp
+  while ($midnight > $timestamp) $midnight -= 86400;
+  return $midnight;
+}
\ No newline at end of file
diff --git a/web/drupal/modules/logger/xmlrpc1.inc b/web/drupal/modules/logger/xmlrpc1.inc
index fa373d9..f930bc9 100644
--- a/web/drupal/modules/logger/xmlrpc1.inc
+++ b/web/drupal/modules/logger/xmlrpc1.inc
@@ -103,7 +103,7 @@ function _logger_measurement_add($auth, $logs) {
         system($command, $return);
 
         if ($return == 0) {
-          // update the night rrd every day at 6AM UTC
+          // update the night rrd every day at 6AM local time
           if (time() > $meterdata->night) {
             $midnight = _logger_midnight(time(), $auth['device']);
             $start = $midnight + 7200; // 2AM local time