Rounding fix

app/src/main/java/info/nightscout/utils/Round.java

@@ -1,15 +1,42 @@
 package info.nightscout.utils;
 
+import android.support.annotation.NonNull;
+import android.util.Log;
+
+import java.math.BigDecimal;
+
 /**
  * Created by mike on 20.06.2016.
  */
 public class Round {
-    public static Double roundTo(double x, Double step) {
+    public static Double roundTo(Double x, Double step) {
+
+        if (step > 1) {
+            return roundToWhole(x, step);
+        } else {
+            return roundToNrOfDecimals(x, getDecimalsFromStep(step));
+        }
+    }
+
+    private static int getDecimalsFromStep(Double step) {
+        String stepString = Double.toString(step);
+        return stepString.substring(stepString.indexOf('.') + 1).length();
+    }
+
+    private static Double roundToNrOfDecimals(Double x, int decimals) {
+        BigDecimal number = new BigDecimal(Double.toString(x));
+        number = number.setScale(decimals, BigDecimal.ROUND_HALF_UP);
+
+        return number.doubleValue();
+    }
+
+    private static Double roundToWhole(Double x, Double step) {
         if (x != 0d) {
             return Math.round(x / step) * step;
         }
         return 0d;
     }
+
     public static Double floorTo(Double x, Double step) {
         if (x != 0d) {
             return Math.floor(x / step) * step;