From eb75ce81969ab391e34bfca992778c4fab23c213 Mon Sep 17 00:00:00 2001
From: "Jan N. Klug" <github@klug.nrw>
Date: Mon, 3 Jul 2023 20:59:46 +0200
Subject: [PATCH] Add unit "calorie"

Signed-off-by: Jan N. Klug <github@klug.nrw>
---
 .../java/org/openhab/core/library/unit/Units.java  |  5 +++++
 .../org/openhab/core/library/unit/UnitsTest.java   | 14 ++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/bundles/org.openhab.core/src/main/java/org/openhab/core/library/unit/Units.java b/bundles/org.openhab.core/src/main/java/org/openhab/core/library/unit/Units.java
index ce910fe11a7..ae175a6d9e7 100644
--- a/bundles/org.openhab.core/src/main/java/org/openhab/core/library/unit/Units.java
+++ b/bundles/org.openhab.core/src/main/java/org/openhab/core/library/unit/Units.java
@@ -12,6 +12,7 @@
  */
 package org.openhab.core.library.unit;
 
+import java.math.BigDecimal;
 import java.math.BigInteger;
 
 import javax.measure.Quantity;
@@ -122,6 +123,8 @@ public final class Units extends CustomUnits {
     public static final Unit<ElectricPotential> VOLT = addUnit(tech.units.indriya.unit.Units.VOLT);
     public static final Unit<ElectricResistance> OHM = addUnit(tech.units.indriya.unit.Units.OHM);
     public static final Unit<Energy> JOULE = addUnit(tech.units.indriya.unit.Units.JOULE);
+    public static final Unit<Energy> CALORIE = addUnit(JOULE.multiply(new BigDecimal("4.184")));
+    public static final Unit<Energy> KILO_CALORIE = addUnit(MetricPrefix.KILO(CALORIE));
     public static final Unit<Energy> WATT_SECOND = addUnit(
             new ProductUnit<>(tech.units.indriya.unit.Units.WATT.multiply(tech.units.indriya.unit.Units.SECOND)));
     public static final Unit<Energy> WATT_HOUR = addUnit(
@@ -241,6 +244,8 @@ public final class Units extends CustomUnits {
         SimpleUnitFormat.getInstance().label(BIT_PER_SECOND, "bit/s");
         SimpleUnitFormat.getInstance().label(BYTE, "B");
         SimpleUnitFormat.getInstance().alias(BYTE, "o");
+        SimpleUnitFormat.getInstance().label(CALORIE, "cal");
+        SimpleUnitFormat.getInstance().label(KILO_CALORIE, "kcal");
         SimpleUnitFormat.getInstance().label(CURIE, "Ci");
         SimpleUnitFormat.getInstance().label(MILLI_CURIE, "mCi");
         SimpleUnitFormat.getInstance().label(MICRO_CURIE, "µCi");
diff --git a/bundles/org.openhab.core/src/test/java/org/openhab/core/library/unit/UnitsTest.java b/bundles/org.openhab.core/src/test/java/org/openhab/core/library/unit/UnitsTest.java
index 68bdd23b414..95264a56ac0 100644
--- a/bundles/org.openhab.core/src/test/java/org/openhab/core/library/unit/UnitsTest.java
+++ b/bundles/org.openhab.core/src/test/java/org/openhab/core/library/unit/UnitsTest.java
@@ -401,6 +401,20 @@ public void testRpm() {
         assertThat(converted.doubleValue(), is(closeTo(1.00, DEFAULT_ERROR)));
     }
 
+    @Test
+    public void testCalorie() {
+        QuantityType<?> oneCalorie = QuantityType.valueOf("1 cal");
+        QuantityType<?> converted = oneCalorie.toUnit("J");
+        assertThat(converted.doubleValue(), is(closeTo(4.184, DEFAULT_ERROR)));
+    }
+
+    @Test
+    public void testKiloCalorie() {
+        QuantityType<?> oneKiloCalorie = QuantityType.valueOf("1 kcal");
+        QuantityType<?> converted = oneKiloCalorie.toUnit("J");
+        assertThat(converted.doubleValue(), is(closeTo(4184.0, DEFAULT_ERROR)));
+    }
+
     private static class QuantityEquals extends IsEqual<Quantity<?>> {
         private Quantity<?> quantity;