From bdf4bb0e23d4a1b59e73ccd8029205bc3b62c4ea Mon Sep 17 00:00:00 2001
From: Paul-Christian Volkmer <code@pcvolkmer.de>
Date: Sun, 22 Jun 2025 13:34:30 +0200
Subject: [PATCH] fix: date alignment for different time zones

---
 src/main/java/dev/pcvolkmer/onco/datamapper/ResultSet.java  | 6 +++++-
 .../java/dev/pcvolkmer/onco/datamapper/ResultSetTest.java   | 4 ++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/main/java/dev/pcvolkmer/onco/datamapper/ResultSet.java b/src/main/java/dev/pcvolkmer/onco/datamapper/ResultSet.java
index 491e083..9175ede 100644
--- a/src/main/java/dev/pcvolkmer/onco/datamapper/ResultSet.java
+++ b/src/main/java/dev/pcvolkmer/onco/datamapper/ResultSet.java
@@ -2,6 +2,8 @@ package dev.pcvolkmer.onco.datamapper;
 
 import dev.pcvolkmer.onco.datamapper.exceptions.DataAccessException;
 
+import java.time.LocalDate;
+import java.time.ZoneId;
 import java.util.Date;
 import java.util.Map;
 
@@ -124,7 +126,9 @@ public class ResultSet {
             return null;
         }
         if (raw instanceof Date) {
-            return (Date) raw;
+            var localDate = LocalDate.parse(raw.toString());
+            // JSON Converter uses UTC timezone
+            return Date.from(localDate.atStartOfDay(ZoneId.of("UTC")).toInstant());
         }
 
         throw new IllegalArgumentException("Cannot convert " + raw.getClass() + " to Date");
diff --git a/src/test/java/dev/pcvolkmer/onco/datamapper/ResultSetTest.java b/src/test/java/dev/pcvolkmer/onco/datamapper/ResultSetTest.java
index 19e815f..ada3b58 100644
--- a/src/test/java/dev/pcvolkmer/onco/datamapper/ResultSetTest.java
+++ b/src/test/java/dev/pcvolkmer/onco/datamapper/ResultSetTest.java
@@ -37,7 +37,7 @@ class ResultSetTest {
     void shouldReturnDateValues() {
         var data = getTestData();
 
-        assertThat(data.getDate("date")).isEqualTo(new Date(Date.from(Instant.parse("2025-06-21T12:00:00Z")).getTime()));
+        assertThat(data.getDate("date")).isEqualTo(new Date(Date.from(Instant.parse("2025-06-21T00:00:00Z")).getTime()));
     }
 
     static ResultSet getTestData() {
@@ -45,7 +45,7 @@ class ResultSetTest {
                 Map.of(
                         "string", "TestString",
                         "int", 42,
-                        "date", new Date(Date.from(Instant.parse("2025-06-21T12:00:00Z")).getTime())
+                        "date", new Date(Date.from(Instant.parse("2025-06-21T02:00:00Z")).getTime())
                 )
         );
     }