From 7ac86043d1b640018df07deb1d94cfacc4e791d2 Mon Sep 17 00:00:00 2001
From: Giorgi <giorgi@giorgi.dev>
Date: Wed, 6 Mar 2024 00:44:59 +0400
Subject: [PATCH] Allow reading ntive DuckDBTimeTz type.

---
 .../Reader/DateTimeVectorDataReader.cs        | 34 +++++++++++++++----
 .../Internal/Reader/VectorDataReaderBase.cs   |  2 +-
 .../DuckDBDataReaderTestAllTypes.cs           | 18 +++++++---
 3 files changed, 41 insertions(+), 13 deletions(-)

diff --git a/DuckDB.NET.Data/Internal/Reader/DateTimeVectorDataReader.cs b/DuckDB.NET.Data/Internal/Reader/DateTimeVectorDataReader.cs
index f16fa94..f481ace 100644
--- a/DuckDB.NET.Data/Internal/Reader/DateTimeVectorDataReader.cs
+++ b/DuckDB.NET.Data/Internal/Reader/DateTimeVectorDataReader.cs
@@ -9,6 +9,9 @@ internal class DateTimeVectorDataReader : VectorDataReaderBase
     private static readonly Type DateTimeType = typeof(DateTime);
     private static readonly Type DateTimeNullableType = typeof(DateTime?);
 
+    private static readonly Type DateTimeOffsetType = typeof(DateTimeOffset);
+    private static readonly Type DateTimeOffsetNullableType = typeof(DateTimeOffset?);
+
 #if NET6_0_OR_GREATER
     private static readonly Type DateOnlyType = typeof(DateOnly);
     private static readonly Type DateOnlyNullableType = typeof(DateOnly?);
@@ -66,7 +69,15 @@ protected override T GetValidValue<T>(ulong offset, Type targetType)
 
         if (DuckDBType == DuckDBType.TimeTz)
         {
-            return (T)(object)GetDateTimeOffset(offset);
+            var timeTz = GetTimeTz(offset);
+
+            if (targetType == DateTimeOffsetType || targetType == DateTimeOffsetNullableType)
+            {
+                var dateTimeOffset = new DateTimeOffset(timeTz.Time.ToDateTime(), TimeSpan.FromSeconds(timeTz.Offset));
+                return (T)(object)dateTimeOffset;
+            }
+
+            return (T)(object)timeTz;
         }
 
         if (DuckDBType == DuckDBType.Timestamp || DuckDBType == DuckDBType.TimestampTz)
@@ -114,7 +125,7 @@ internal override object GetValue(ulong offset, Type targetType)
         {
             DuckDBType.Date => GetDate(offset, targetType),
             DuckDBType.Time => GetTime(offset, targetType),
-            DuckDBType.TimeTz => GetDateTimeOffset(offset),
+            DuckDBType.TimeTz => GetDateTimeOffset(offset, targetType),
             DuckDBType.Timestamp => GetDateTime(offset, targetType),
             DuckDBType.TimestampTz => GetDateTime(offset, targetType),
             DuckDBType.TimestampS => GetDateTime(offset, targetType, 1000000),
@@ -124,6 +135,13 @@ internal override object GetValue(ulong offset, Type targetType)
         };
     }
 
+    private DuckDBTimeTz GetTimeTz(ulong offset)
+    {
+        var data = GetFieldData<DuckDBTimeTzStruct>(offset);
+
+        return NativeMethods.DateTime.DuckDBFromTimeTz(data);
+    }
+
     private DuckDBTimeOnly GetTimeOnly(ulong offset)
     {
         return NativeMethods.DateTime.DuckDBFromTime(GetFieldData<DuckDBTime>(offset));
@@ -184,13 +202,15 @@ private object GetDateTime(ulong offset, Type targetType, int factor = 1, int di
         return NativeMethods.DateTime.DuckDBFromTimestamp(data);
     }
 
-    private DateTimeOffset GetDateTimeOffset(ulong offset)
+    private object GetDateTimeOffset(ulong offset, Type targetType)
     {
-        var data = GetFieldData<DuckDBTimeTzStruct>(offset);
-
-        var timeTz = NativeMethods.DateTime.DuckDBFromTimeTz(data);
+        var timeTz = GetTimeTz(offset);
 
+        if (targetType == typeof(DateTimeOffset))
+        {
+            return new DateTimeOffset(timeTz.Time.ToDateTime(), TimeSpan.FromSeconds(timeTz.Offset));
+        }
 
-        return new DateTimeOffset(timeTz.Time.ToDateTime(), TimeSpan.FromSeconds(timeTz.Offset));
+        return timeTz;
     }
 }
\ No newline at end of file
diff --git a/DuckDB.NET.Data/Internal/Reader/VectorDataReaderBase.cs b/DuckDB.NET.Data/Internal/Reader/VectorDataReaderBase.cs
index 2ee2fa4..d45f113 100644
--- a/DuckDB.NET.Data/Internal/Reader/VectorDataReaderBase.cs
+++ b/DuckDB.NET.Data/Internal/Reader/VectorDataReaderBase.cs
@@ -169,7 +169,7 @@ protected virtual Type GetColumnProviderSpecificType()
             DuckDBType.Interval => typeof(DuckDBInterval),
             DuckDBType.Date => typeof(DuckDBDateOnly),
             DuckDBType.Time => typeof(DuckDBTimeOnly),
-            DuckDBType.TimeTz => typeof(DateTimeOffset),
+            DuckDBType.TimeTz => typeof(DuckDBTimeTz),
             DuckDBType.HugeInt => typeof(DuckDBHugeInt),
             DuckDBType.UnsignedHugeInt => typeof(DuckDBUHugeInt),
             DuckDBType.Varchar => typeof(string),
diff --git a/DuckDB.NET.Test/DuckDBDataReaderTestAllTypes.cs b/DuckDB.NET.Test/DuckDBDataReaderTestAllTypes.cs
index c94375a..0ffbea0 100644
--- a/DuckDB.NET.Test/DuckDBDataReaderTestAllTypes.cs
+++ b/DuckDB.NET.Test/DuckDBDataReaderTestAllTypes.cs
@@ -231,14 +231,22 @@ public void ReadTimeStampNS()
         }, typeof(DuckDBTimestamp));
     }
 
-    [Fact(Skip = "These dates can't be expressed by DateTime or is unsupported by this library")]
+    [Fact]
     public void ReadTimeTZ()
     {
-        VerifyDataStruct("time_tz", 17, new List<DuckDBTimestamp>
+        VerifyDataStruct("time_tz", 17, new List<DuckDBTimeTz>
         {
-            new(new(-290308, 12, 22), new(0,0,0)),
-            new(new(294247, 1, 10), new(4,0,54,775806))
-        });
+            new()
+            {
+                Offset = (int)new TimeSpan(15,59,59).TotalSeconds,
+                Time = new DuckDBTimeOnly()
+            },
+            new()
+            {
+                Offset = -(int)new TimeSpan(15,59,59).TotalSeconds,
+                Time = new DuckDBTimeOnly(24,0,0)
+            },
+        }, readProviderSpecificValue: true);
     }
 
     [Fact]