fix: Fixed agent windows version

agent/internal/sync/sync.go

@@ -11,6 +11,7 @@ import (
 	"net/http"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"runtime"
 	"strings"
 	"time"
@@ -265,6 +266,11 @@ func handleDeleteKey(cmd *pb.ServerCommand) {
 }
 
 func handleUpdateAgent(cmd *pb.ServerCommand) {
+	if runtime.GOOS == "windows" {
+		handleUpdateAgentWindows(cmd)
+		return
+	}
+
 	u := cmd.UpdateAgent
 	arch := runtime.GOARCH // "amd64" or "arm64"
 	tag := "agent%2Fv" + u.Version
@@ -305,6 +311,47 @@ func handleUpdateAgent(cmd *pb.ServerCommand) {
 	exec.Command("systemctl", "restart", "vantage-agent").Run()
 }
 
+// handleUpdateAgentWindows downloads the latest MSI and launches msiexec to
+// perform a MajorUpgrade. msiexec is started DETACHED (via "cmd /c start") so
+// that when the upgrade stops the VantageAgent service, nssm's process-tree
+// kill of this agent does not also kill the installer mid-flight. Config
+// (server_id, agent_token) is preserved by setup.ps1 on upgrade.
+func handleUpdateAgentWindows(cmd *pb.ServerCommand) {
+	u := cmd.UpdateAgent
+	tag := "agent%2Fv" + u.Version
+	msiURL := fmt.Sprintf("%s/mrhid6/vantage/releases/download/%s/vantage-agent.msi", u.GiteaBaseURL, tag)
+	checksumURL := fmt.Sprintf("%s/mrhid6/vantage/releases/download/%s/checksums-msi.txt", u.GiteaBaseURL, tag)
+
+	log.Printf("updating agent to v%s from %s (cmd=%s)", u.Version, u.GiteaBaseURL, cmd.CommandId)
+
+	msiPath := filepath.Join(os.TempDir(), "vantage-agent-update.msi")
+	if err := downloadFile(msiURL, msiPath); err != nil {
+		log.Printf("update download failed (cmd=%s): %v", cmd.CommandId, err)
+		return
+	}
+
+	checksumData, err := httpGetBytes(checksumURL)
+	if err != nil {
+		log.Printf("update checksum fetch failed (cmd=%s): %v", cmd.CommandId, err)
+		return
+	}
+	if err := verifyChecksum(msiPath, "vantage-agent.msi", checksumData); err != nil {
+		log.Printf("update checksum mismatch (cmd=%s): %v", cmd.CommandId, err)
+		os.Remove(msiPath)
+		return
+	}
+
+	logPath := filepath.Join(os.TempDir(), "vantage-agent-msi.log")
+	log.Printf("launching msiexec for upgrade to v%s (cmd=%s)", u.Version, cmd.CommandId)
+	// "start" detaches msiexec from this process tree so the service stop
+	// during the upgrade does not terminate the installer.
+	up := exec.Command("cmd", "/c", "start", "", "/wait", "msiexec", "/i", msiPath, "/qn", "/norestart", "/l*v", logPath)
+	if err := up.Start(); err != nil {
+		log.Printf("failed to launch msiexec (cmd=%s): %v", cmd.CommandId, err)
+		return
+	}
+}
+
 func downloadFile(url, dest string) error {
 	resp, err := http.Get(url) //nolint:gosec
 	if err != nil {