fix: min/max dates not always correct when timezoneOffsetInMinutes is…

… set

android/src/main/java/com/henninghall/date_picker/DatePickerManager.java

@@ -1,18 +1,10 @@
 package com.henninghall.date_picker;
 
 
-import android.app.AlertDialog;
-import android.app.Dialog;
-import android.app.DialogFragment;
-import android.content.DialogInterface;
-import android.os.Bundle;
-import android.view.View;
 import android.widget.LinearLayout;
 import android.widget.RelativeLayout;
 
 import com.facebook.react.bridge.Dynamic;
-import com.facebook.react.bridge.ReactApplicationContext;
-import com.facebook.react.bridge.ReactMethod;
 import com.facebook.react.bridge.ReadableArray;
 import com.facebook.react.common.MapBuilder;
 import com.facebook.react.uimanager.SimpleViewManager;
@@ -29,7 +21,7 @@
 import com.henninghall.date_picker.props.MinuteIntervalProp;
 import com.henninghall.date_picker.props.ModeProp;
 import com.henninghall.date_picker.props.TextColorProp;
-import com.henninghall.date_picker.props.UtcProp;
+import com.henninghall.date_picker.props.TimezoneOffsetInMinutesProp;
 
 
 import java.lang.reflect.Method;
@@ -54,7 +46,7 @@ public PickerView createViewInstance(ThemedReactContext context) {
   }
 
   @ReactPropGroup(names = { DateProp.name, ModeProp.name, LocaleProp.name, MaximumDateProp.name,
-          MinimumDateProp.name, FadeToColorProp.name, TextColorProp.name, UtcProp.name, MinuteIntervalProp.name,
+          MinimumDateProp.name, FadeToColorProp.name, TextColorProp.name, TimezoneOffsetInMinutesProp.name, MinuteIntervalProp.name,
           VariantProp.name, DividerHeightProp.name, Is24hourSourceProp.name
   })
   public void setProps(PickerView view, int index, Dynamic value) {

android/src/main/java/com/henninghall/date_picker/PickerView.java

@@ -11,7 +11,7 @@
 import com.henninghall.date_picker.props.MaximumDateProp;
 import com.henninghall.date_picker.props.MinimumDateProp;
 import com.henninghall.date_picker.props.MinuteIntervalProp;
-import com.henninghall.date_picker.props.UtcProp;
+import com.henninghall.date_picker.props.TimezoneOffsetInMinutesProp;
 import com.henninghall.date_picker.props.VariantProp;
 import com.henninghall.date_picker.props.DateProp;
 import com.henninghall.date_picker.props.FadeToColorProp;
@@ -77,7 +77,7 @@ public void update() {
 
         if (didUpdate(DateProp.name, HeightProp.name, LocaleProp.name,
                 MaximumDateProp.name, MinimumDateProp.name, MinuteIntervalProp.name, ModeProp.name,
-                UtcProp.name, VariantProp.name
+                TimezoneOffsetInMinutesProp.name, VariantProp.name
         )) {
             uiManager.updateDisplayValues();
         }

android/src/main/java/com/henninghall/date_picker/State.java

@@ -17,7 +17,7 @@
 import com.henninghall.date_picker.props.ModeProp;
 import com.henninghall.date_picker.props.Prop;
 import com.henninghall.date_picker.props.TextColorProp;
-import com.henninghall.date_picker.props.UtcProp;
+import com.henninghall.date_picker.props.TimezoneOffsetInMinutesProp;
 
 import java.util.Calendar;
 import java.util.HashMap;
@@ -35,7 +35,7 @@ public class State {
     private final MinuteIntervalProp minuteIntervalProp = new MinuteIntervalProp();
     private final MinimumDateProp minimumDateProp = new MinimumDateProp();
     private final MaximumDateProp maximumDateProp = new MaximumDateProp();
-    private final UtcProp utcProp = new UtcProp();
+    private final TimezoneOffsetInMinutesProp timezoneOffsetInMinutesProp = new TimezoneOffsetInMinutesProp();
     private final HeightProp heightProp = new HeightProp();
     private final VariantProp variantProp = new VariantProp();
     private final DividerHeightProp dividerHeightProp = new DividerHeightProp();
@@ -50,7 +50,7 @@ public class State {
         put(MinuteIntervalProp.name, minuteIntervalProp);
         put(MinimumDateProp.name, minimumDateProp);
         put(MaximumDateProp.name, maximumDateProp);
-        put(UtcProp.name, utcProp);
+        put(TimezoneOffsetInMinutesProp.name, timezoneOffsetInMinutesProp);
         put(HeightProp.name, heightProp);
         put(VariantProp.name, variantProp);
         put(DividerHeightProp.name, dividerHeightProp);
@@ -91,18 +91,21 @@ public Locale getLocale() {
     }
 
     public Calendar getMinimumDate() {
-        DateBoundary db = new DateBoundary(getTimeZone(), (String) minimumDateProp.getValue());
-        return db.get();
+        return Utils.isoToCalendar(minimumDateProp.getValue(), getTimeZone());
     }
 
     public Calendar getMaximumDate() {
-        DateBoundary db = new DateBoundary(getTimeZone(), (String) maximumDateProp.getValue());
-        return db.get();
+        return Utils.isoToCalendar(maximumDateProp.getValue(), getTimeZone());
     }
 
     public TimeZone getTimeZone() {
-        boolean utc = (boolean) utcProp.getValue();
-        return utc ? TimeZone.getTimeZone("UTC") : TimeZone.getDefault();
+        int totalOffsetMinutes = Math.abs(timezoneOffsetInMinutesProp.getValue());
+        char offsetDirection = timezoneOffsetInMinutesProp.getValue() < 0 ? '-' : '+';
+        int offsetHours = (int) Math.floor(totalOffsetMinutes / 60f);
+        int offsetMinutes = totalOffsetMinutes - offsetHours * 60;
+        String timeZoneId = "GMT" + offsetDirection + offsetHours + ":" + Utils.toPaddedMinutes(offsetMinutes);
+        TimeZone zone = TimeZone.getTimeZone(timeZoneId);
+        return zone;
     }
 
     public String getIsoDate() {

android/src/main/java/com/henninghall/date_picker/Utils.java

@@ -9,6 +9,7 @@
 
 import net.time4j.PrettyTime;
 
+import java.text.DecimalFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
@@ -110,4 +111,9 @@ public static String getLocalisedStringFromResources(Locale locale, String tagNa
     public static int toDp(int pixels){
         return (int) (pixels * DatePickerPackage.context.getResources().getDisplayMetrics().density);
     }
+
+    public static String toPaddedMinutes(int minutes){
+        DecimalFormat df = new DecimalFormat("00");
+        return df.format(minutes);
+    }
 }

android/src/main/java/com/henninghall/date_picker/props/TimezoneOffsetInMinutesProp.java

@@ -0,0 +1,12 @@
+package com.henninghall.date_picker.props;
+
+import com.facebook.react.bridge.Dynamic;
+
+public class TimezoneOffsetInMinutesProp extends Prop<Integer> {
+    public static final String name = "timezoneOffsetInMinutes";
+
+    @Override
+    Integer toValue(Dynamic value) {
+        return value.asInt();
+    }
+}