From b5a4c71eff758d87f0cd771eaca7626af9a42ba5 Mon Sep 17 00:00:00 2001
From: TheTechnician27 <TheTechnician27@users.noreply.github.com>
Date: Thu, 16 Oct 2025 00:39:37 -0500
Subject: [PATCH] RTC: Add option to choose between system locale and
 yyyy-MM-dd HH:mm:ss

---
 pcsx2-qt/Settings/EmulationSettingsWidget.cpp | 18 +++++++++++++++---
 pcsx2-qt/Settings/EmulationSettingsWidget.h   |  1 +
 pcsx2-qt/Settings/EmulationSettingsWidget.ui  |  7 +++++++
 pcsx2/Config.h                                |  1 +
 pcsx2/Pcsx2Config.cpp                         |  2 ++
 5 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/pcsx2-qt/Settings/EmulationSettingsWidget.cpp b/pcsx2-qt/Settings/EmulationSettingsWidget.cpp
index e2ef093cf3..9d96cb9165 100644
--- a/pcsx2-qt/Settings/EmulationSettingsWidget.cpp
+++ b/pcsx2-qt/Settings/EmulationSettingsWidget.cpp
@@ -51,7 +51,10 @@ EmulationSettingsWidget::EmulationSettingsWidget(SettingsWindow* settings_dialog
 		m_ui.rtcDateTime->setDateRange(QDate(2000, 1, 1), QDate(2099, 12, 31));
 		SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.manuallySetRealTimeClock, "EmuCore", "ManuallySetRealTimeClock", false);
 		connect(m_ui.manuallySetRealTimeClock, &QCheckBox::checkStateChanged, this, &EmulationSettingsWidget::onManuallySetRealTimeClockChanged);
+		SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.rtcUseSystemLocaleFormat, "EmuCore", "UseSystemLocaleFormat", false);
+		connect(m_ui.rtcUseSystemLocaleFormat, &QCheckBox::checkStateChanged, this, &EmulationSettingsWidget::onUseSystemLocaleFormatChanged);
 		EmulationSettingsWidget::onManuallySetRealTimeClockChanged();
+		EmulationSettingsWidget::onUseSystemLocaleFormatChanged();
 
 		m_ui.eeCycleRate->insertItem(0,
 			tr("Use Global Setting [%1]")
@@ -159,10 +162,12 @@ EmulationSettingsWidget::EmulationSettingsWidget(SettingsWindow* settings_dialog
 	dialog()->registerWidgetHelp(m_ui.manuallySetRealTimeClock, tr("Manually Set Real-Time Clock"), tr("Unchecked"),
 		tr("Manually set a real-time clock to use for the virtual PlayStation 2 instead of using your OS' system clock."));
 	dialog()->registerWidgetHelp(m_ui.rtcDateTime, tr("Real-Time Clock"), tr("Current date and time"),
-		tr("Real-time clock (RTC) used by the virtual PlayStation 2. Date format is the same as the one used by your OS. "
-		   "This time is only applied upon booting the PS2; changing it while in-game will have no effect. "
-		   "NOTE: This assumes you have your PS2 set to the default timezone of GMT+0 and default DST of Summer Time. "
+		tr("Real-time clock (RTC) used by the virtual PlayStation 2.<br>"
+		   "This time is only applied upon booting the PS2; changing it while in-game will have no effect.<br>"
+		   "NOTE: This assumes you have your PS2 set to the default timezone of GMT+0 and default DST of Summer Time.<br>"
 		   "Some games require an RTC date/time set after their release date."));
+	dialog()->registerWidgetHelp(m_ui.rtcUseSystemLocaleFormat, tr("Use System Locale Format"), tr("User Preference"),
+		tr("Uses the operating system's date/time format rather than \"yyyy-MM-dd HH:mm:ss\". May exclude seconds."));
 
 	updateOptimalFramePacing();
 	updateUseVSyncForTimingEnabled();
@@ -314,4 +319,11 @@ void EmulationSettingsWidget::onManuallySetRealTimeClockChanged()
 {
 	const bool enabled = dialog()->getEffectiveBoolValue("EmuCore", "ManuallySetRealTimeClock", false);
 	m_ui.rtcDateTime->setEnabled(enabled);
+	m_ui.rtcUseSystemLocaleFormat->setEnabled(enabled);
+}
+
+void EmulationSettingsWidget::onUseSystemLocaleFormatChanged()
+{
+	const bool enabled = dialog()->getEffectiveBoolValue("EmuCore", "UseSystemLocaleFormat", false);
+	m_ui.rtcDateTime->setDisplayFormat(enabled ? QLocale::system().dateTimeFormat(QLocale::ShortFormat) : "yyyy-MM-dd HH:mm:ss");
 }
diff --git a/pcsx2-qt/Settings/EmulationSettingsWidget.h b/pcsx2-qt/Settings/EmulationSettingsWidget.h
index 0af89e6ded..6472e39285 100644
--- a/pcsx2-qt/Settings/EmulationSettingsWidget.h
+++ b/pcsx2-qt/Settings/EmulationSettingsWidget.h
@@ -24,6 +24,7 @@ private:
 	void updateOptimalFramePacing();
 	void updateUseVSyncForTimingEnabled();
 	void onManuallySetRealTimeClockChanged();
+	void onUseSystemLocaleFormatChanged();
 
 	Ui::EmulationSettingsWidget m_ui;
 };
diff --git a/pcsx2-qt/Settings/EmulationSettingsWidget.ui b/pcsx2-qt/Settings/EmulationSettingsWidget.ui
index 9b620c26f0..320b0a3b6f 100644
--- a/pcsx2-qt/Settings/EmulationSettingsWidget.ui
+++ b/pcsx2-qt/Settings/EmulationSettingsWidget.ui
@@ -266,6 +266,13 @@
       <item row="0" column="1">
        <widget class="QDateTimeEdit" name="rtcDateTime"/>
       </item>
+      <item row="1" column="0">
+       <widget class="QCheckBox" name="rtcUseSystemLocaleFormat">
+        <property name="text">
+         <string>Use System Locale Format</string>
+        </property>
+       </widget>
+      </item>
      </layout>
     </widget>
    </item>
diff --git a/pcsx2/Config.h b/pcsx2/Config.h
index 9ad5fc1031..9b4a948f85 100644
--- a/pcsx2/Config.h
+++ b/pcsx2/Config.h
@@ -1315,6 +1315,7 @@ struct Pcsx2Config
 		BackupSavestate : 1,
 		McdFolderAutoManage : 1,
 		ManuallySetRealTimeClock : 1,
+		UseSystemLocaleFormat : 1, // presents OS time format instead of yyyy-MM-dd HH:mm:ss for manual RTC
 
 		HostFs : 1,
 
diff --git a/pcsx2/Pcsx2Config.cpp b/pcsx2/Pcsx2Config.cpp
index 3d48bf3978..a239705293 100644
--- a/pcsx2/Pcsx2Config.cpp
+++ b/pcsx2/Pcsx2Config.cpp
@@ -1924,6 +1924,7 @@ Pcsx2Config::Pcsx2Config()
 	WarnAboutUnsafeSettings = true;
 	EnableDiscordPresence = false;
 	ManuallySetRealTimeClock = false;
+	UseSystemLocaleFormat = false;
 
 	// To be moved to FileMemoryCard pluign (someday)
 	for (uint slot = 0; slot < 8; ++slot)
@@ -1973,6 +1974,7 @@ void Pcsx2Config::LoadSaveCore(SettingsWrapper& wrap)
 	SettingsWrapBitBool(WarnAboutUnsafeSettings);
 
 	SettingsWrapBitBool(ManuallySetRealTimeClock);
+	SettingsWrapBitBool(UseSystemLocaleFormat);
 
 	// Process various sub-components: