From ecce6770b7cea29b47586e564baf965ef2e07621 Mon Sep 17 00:00:00 2001
From: MonsterDruide1 <5958456@gmail.com>
Date: Sat, 16 May 2026 13:17:45 +0200
Subject: [PATCH 1/2] time: Implement `DateTime::DateTime(const DateTimeUtc&)`

---
 include/time/seadDateTime.h       |  1 +
 modules/src/time/seadDateTime.cpp | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/include/time/seadDateTime.h b/include/time/seadDateTime.h
index 6054e46b..1ce82146 100644
--- a/include/time/seadDateTime.h
+++ b/include/time/seadDateTime.h
@@ -16,6 +16,7 @@ class DateTime
     DateTime(const CalendarTime::Year& year, const CalendarTime::Month& month,
              const CalendarTime::Day& day, const CalendarTime::Hour& hour,
              const CalendarTime::Minute& minute, const CalendarTime::Second& second);
+    DateTime(const DateTimeUtc& unused);
 
     DateTime& operator+=(DateSpan span)
     {
diff --git a/modules/src/time/seadDateTime.cpp b/modules/src/time/seadDateTime.cpp
index a0e8e03a..58b2bae1 100644
--- a/modules/src/time/seadDateTime.cpp
+++ b/modules/src/time/seadDateTime.cpp
@@ -126,6 +126,26 @@ DateTime::DateTime(const CalendarTime::Year& year, const CalendarTime::Month& mo
     setUnixTime(year, month, day, hour, minute, second);
 }
 
+DateTime::DateTime(const DateTimeUtc& unused)
+{
+#ifdef NNSDK
+    initializeSystemTimeModule();
+
+    nn::time::CalendarTime ctime;
+    // BUG: uses uninitialized `mUnixTime` instead of parameter `time`.
+    nn::time::PosixTime time = {mUnixTime};
+    nn::time::ToCalendarTime(&ctime, nullptr, time);
+
+    const auto year = CalendarTime::Year(ctime.year);
+    const auto month = CalendarTime::Month::makeFromValueOneOrigin(ctime.month);
+    const auto day = CalendarTime::Day(ctime.day);
+    const auto hour = CalendarTime::Hour(ctime.hour);
+    const auto minute = CalendarTime::Minute(ctime.minute);
+    const auto second = CalendarTime::Second(ctime.second);
+    setUnixTime(year, month, day, hour, minute, second);
+#endif
+}
+
 u64 DateTime::setNow()
 {
 #ifdef NNSDK

From 08af81a46fdfbe8fe1fb06b1888b71f37883361e Mon Sep 17 00:00:00 2001
From: MonsterDruide1 <5958456@gmail.com>
Date: Sat, 16 May 2026 13:20:57 +0200
Subject: [PATCH 2/2] fix compiler warning/error

---
 modules/src/time/seadDateTime.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/src/time/seadDateTime.cpp b/modules/src/time/seadDateTime.cpp
index 58b2bae1..2ddd5808 100644
--- a/modules/src/time/seadDateTime.cpp
+++ b/modules/src/time/seadDateTime.cpp
@@ -126,7 +126,7 @@ DateTime::DateTime(const CalendarTime::Year& year, const CalendarTime::Month& mo
     setUnixTime(year, month, day, hour, minute, second);
 }
 
-DateTime::DateTime(const DateTimeUtc& unused)
+DateTime::DateTime([[maybe_unused]] const DateTimeUtc& unused)
 {
 #ifdef NNSDK
     initializeSystemTimeModule();