From 445ffbda96d6283e081cd407ccae0c98342b3ef6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dani=C3=ABl=20van=20Os?= <daniel@supercell.nl>
Date: Mon, 29 Nov 2021 16:19:09 +0100
Subject: [PATCH] Fix issue with missing gas values (#11639)
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This commit fixes a crash that happens when the smart meter does not provide gas values. The crash was caused by the empty timestamp.

Signed-off-by: Daniël van Os <daniel@supercell.nl>
---
 .../internal/HomeWizardHandler.java           | 62 ++++++++++++-------
 .../homewizard/internal/P1Payload.java        |  2 +-
 2 files changed, 39 insertions(+), 25 deletions(-)

diff --git a/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/HomeWizardHandler.java b/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/HomeWizardHandler.java
index 3e47191f37421..7389dc8853388 100644
--- a/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/HomeWizardHandler.java
+++ b/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/HomeWizardHandler.java
@@ -29,6 +29,8 @@
 import org.openhab.core.thing.ThingStatusDetail;
 import org.openhab.core.thing.binding.BaseThingHandler;
 import org.openhab.core.types.Command;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import com.google.gson.FieldNamingPolicy;
 import com.google.gson.Gson;
@@ -43,6 +45,7 @@
 @NonNullByDefault
 public class HomeWizardHandler extends BaseThingHandler {
 
+    private final Logger logger = LoggerFactory.getLogger(HomeWizardHandler.class);
     private final Gson gson = new GsonBuilder().setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)
             .create();
 
@@ -171,30 +174,41 @@ private void pollingCode() {
         updateState(HomeWizardBindingConstants.CHANNEL_ACTIVE_POWER_L3,
                 new QuantityType<>(payload.getActivePowerL3W(), Units.WATT));
 
-        updateState(HomeWizardBindingConstants.CHANNEL_TOTAL_GAS,
-                new QuantityType<>(payload.getTotalGasM3(), SIUnits.CUBIC_METRE));
-
-        // 210119164000
+        // If no data from the gas meter is present, the json value will be null, which means gson ignores it,
+        // leaving the value in the payload object at 0.
         long dtv = payload.getGasTimestamp();
-        long seconds = dtv % 100;
-
-        dtv /= 100;
-        long minutes = dtv % 100;
-
-        dtv /= 100;
-        long hours = dtv % 100;
-
-        dtv /= 100;
-        long day = dtv % 100;
-
-        dtv /= 100;
-        long month = dtv % 100;
-
-        dtv /= 100;
-        long year = dtv + 2000; // Where (When?) have I seen this before?
-
-        DateTimeType dtt = DateTimeType
-                .valueOf(String.format("%04d-%02d-%02dT%02d:%02d:%02d", year, month, day, hours, minutes, seconds));
-        updateState(HomeWizardBindingConstants.CHANNEL_GAS_TIMESTAMP, dtt);
+        if (dtv > 0) {
+            updateState(HomeWizardBindingConstants.CHANNEL_TOTAL_GAS,
+                    new QuantityType<>(payload.getTotalGasM3(), SIUnits.CUBIC_METRE));
+
+            // 210119164000
+            long seconds = dtv % 100;
+
+            dtv /= 100;
+            long minutes = dtv % 100;
+
+            dtv /= 100;
+            long hours = dtv % 100;
+
+            dtv /= 100;
+            long day = dtv % 100;
+
+            dtv /= 100;
+            long month = dtv % 100;
+
+            dtv /= 100;
+            long year = dtv + 2000;
+
+            String dateString = String.format("%04d-%02d-%02dT%02d:%02d:%02d", year, month, day, hours, minutes,
+                    seconds);
+            try {
+                DateTimeType dtt = DateTimeType.valueOf(dateString);
+                updateState(HomeWizardBindingConstants.CHANNEL_GAS_TIMESTAMP, dtt);
+                updateState(HomeWizardBindingConstants.CHANNEL_TOTAL_GAS,
+                        new QuantityType<>(payload.getTotalGasM3(), SIUnits.CUBIC_METRE));
+            } catch (java.time.format.DateTimeParseException e) {
+                logger.warn("Unable to parse Gas timestamp {} / {}", payload.getGasTimestamp(), dateString);
+            }
+        }
     }
 }
diff --git a/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/P1Payload.java b/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/P1Payload.java
index 6fd42b7e92ec9..33c49b3a81615 100644
--- a/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/P1Payload.java
+++ b/bundles/org.openhab.binding.homewizard/src/main/java/org/openhab/binding/homewizard/internal/P1Payload.java
@@ -43,7 +43,7 @@ public class P1Payload {
     private double activePowerL2W;
     private double activePowerL3W;
     private double totalGasM3;
-    private long gasTimestamp;
+    private long gasTimestamp = 0;
 
     /**
      * Getter for the smart meter version