From 25630326c75e0398664444dd45e0d898fc4effdc Mon Sep 17 00:00:00 2001
From: "belevo\\mh" <mh@belevo.ch>
Date: Wed, 17 Dec 2025 08:23:24 +0100
Subject: [PATCH] no message

---
 Energy_Pie/module.php | 46 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/Energy_Pie/module.php b/Energy_Pie/module.php
index 45de3cf..410f306 100644
--- a/Energy_Pie/module.php
+++ b/Energy_Pie/module.php
@@ -173,6 +173,52 @@ private function RecalculateAndPush(): void
         }
     }
 
+
+     private function readDelta($varId, $tStart, $tEnd)
+    {
+        if (!is_int($tStart)) {
+            $tStart = strtotime($tStart);
+        }
+        if (!is_int($tEnd)) {
+            $tEnd = strtotime($tEnd);
+        }
+
+        $archiveID = @IPS_GetInstanceListByModuleID('{43192F0B-135B-4CE7-A0A7-1475603F3060}')[0];
+        if (!$archiveID || !IPS_VariableExists($varId)) {
+            return 0.0;
+        }
+
+        $values = @AC_GetLoggedValues($archiveID, $varId, $tStart - 86400, $tEnd + 86400, 0);
+        if (empty($values)) {
+            return 0.0;
+        }
+
+        usort($values, fn($a, $b) => (int)$a['TimeStamp'] <=> (int)$b['TimeStamp']);
+        $vStart = null;
+        $vEnd   = null;
+
+        foreach ($values as $v) {
+            if ($v['TimeStamp'] <= $tStart) {
+                $vStart = $v['Value'];
+            }
+            if ($v['TimeStamp'] <= $tEnd) {
+                $vEnd = $v['Value'];
+            }
+            if ($v['TimeStamp'] > $tEnd) {
+                break;
+            }
+        }
+
+        if ($vStart === null) {
+            $vStart = (float)GetValue($varId);
+        }
+        if ($vEnd === null) {
+            $vEnd = (float)GetValue($varId);
+        }
+
+        $diff = $vEnd - $vStart;
+        return ($diff < 0) ? 0.0 : $diff;
+    }
     /**
      * Buttons for quick navigation.
      */