From 8b779bdae2f7758fb25e83775854d3d5cf7fa106 Mon Sep 17 00:00:00 2001
From: SIrHrVedel <38987957+SirHrVedel@users.noreply.github.com>
Date: Sun, 7 Jun 2026 22:41:37 +0200
Subject: [PATCH] Fix Windows system version detection

---
 src/Cafe/CafeSystem.cpp | 34 ++++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/src/Cafe/CafeSystem.cpp b/src/Cafe/CafeSystem.cpp
index 096d90f4..d466b66c 100644
--- a/src/Cafe/CafeSystem.cpp
+++ b/src/Cafe/CafeSystem.cpp
@@ -499,21 +499,43 @@ namespace CafeSystem
 	std::string GetWindowsNamedVersion(uint32& buildNumber)
 	{
 		char productName[256];
+		char buildNumberStr[32];
+		char featureVersion[32];
 		HKEY hKey;
 		DWORD dwType = REG_SZ;
 		DWORD dwSize = sizeof(productName);
+		buildNumber = 0;
+		featureVersion[0] = '\0';
 		if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion", 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS)
 		{
 			if (RegQueryValueExA(hKey, "ProductName", NULL, &dwType, (LPBYTE)productName, &dwSize) != ERROR_SUCCESS)
 				strcpy(productName, "Windows");
+			dwType = REG_SZ;
+			dwSize = sizeof(buildNumberStr);
+			if (RegQueryValueExA(hKey, "CurrentBuildNumber", NULL, &dwType, (LPBYTE)buildNumberStr, &dwSize) == ERROR_SUCCESS)
+				buildNumber = (uint32)atoi(buildNumberStr);
+			dwType = REG_SZ;
+			dwSize = sizeof(featureVersion);
+			if (RegQueryValueExA(hKey, "DisplayVersion", NULL, &dwType, (LPBYTE)featureVersion, &dwSize) != ERROR_SUCCESS)
+			{
+				dwType = REG_SZ;
+				dwSize = sizeof(featureVersion);
+				if (RegQueryValueExA(hKey, "ReleaseId", NULL, &dwType, (LPBYTE)featureVersion, &dwSize) != ERROR_SUCCESS)
+					featureVersion[0] = '\0';
+			}
 			RegCloseKey(hKey);
 		}
-		OSVERSIONINFO osvi;
-		ZeroMemory(&osvi, sizeof(OSVERSIONINFO));
-		osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
-		GetVersionEx(&osvi);
-		buildNumber = osvi.dwBuildNumber;
-		return std::string(productName);
+		std::string result(productName);
+		// ProductName can still read "Windows 10" on Windows 11 after an in-place upgrade
+		if (buildNumber >= 22000)
+		{
+			size_t pos = result.find("Windows 10");
+			if (pos != std::string::npos)
+				result.replace(pos, 10, "Windows 11");
+		}
+		if (featureVersion[0] != '\0')
+			result += fmt::format(" {}", featureVersion);
+		return result;
 	}
 	#endif