vpnem: VPN infrastructure with load-balanced multi-protocol nodesHEADmain

- Multi-protocol VPS nodes (VLESS-REALITY + Hysteria2 + SOCKS5)
- Smart load balancing via recommendation API
- Windows/Linux client (Go + Wails + sing-box)
- Server API with RealIP detection and connection tracking
- Auto-deployment via vpnui control plane
- Silent Windows installer with UAC elevation
- Load-based server recommendation (no sticky sessions)
- Best Server one-click connection workflow

1 files changed, 108 insertions, 0 deletions

diff --git a/cmd/client/main.go b/cmd/client/main.go
new file mode 100644
index 0000000..a2cabbf
--- /dev/null
+++ b/cmd/client/main.go
@@ -0,0 +1,108 @@
+package main
+
+import (
+	"embed"
+	"flag"
+	"log"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/wailsapp/wails/v2"
+	"github.com/wailsapp/wails/v2/pkg/options"
+	"github.com/wailsapp/wails/v2/pkg/options/assetserver"
+)
+
+//go:embed frontend/dist
+var assets embed.FS
+
+func main() {
+	apiURL := flag.String("api", "https://vpn.em-sysadmin.xyz", "API server URL")
+	dataDir := flag.String("data", defaultDataDir(), "data directory")
+	flag.Parse()
+
+	// Ensure data dir exists
+	os.MkdirAll(*dataDir, 0o755)
+
+	// Setup file logging so we always have diagnostics
+	logPath := filepath.Join(*dataDir, "vpnem.log")
+	logFile, err := os.OpenFile(logPath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
+	if err == nil {
+		log.SetOutput(logFile)
+		defer logFile.Close()
+	}
+
+	log.Printf("vpnem starting, data=%s, api=%s, os=%s", *dataDir, *apiURL, runtime.GOOS)
+
+	// Kill previous instances of vpnem and sing-box
+	killPrevious()
+
+	// Clean stale update artifacts from crashed updates
+	if runtime.GOOS == "windows" {
+		exe, _ := os.Executable()
+		os.Remove(exe + ".old")        // leftover from failed update
+		os.Remove(exe + ".tmp")        // leftover temp
+		os.Remove(filepath.Join(*dataDir, "vpnem-new.exe"))
+	} else {
+		exe, _ := os.Executable()
+		os.Remove(exe + ".old")
+		os.Remove(filepath.Join(*dataDir, "vpnem-new"))
+	}
+
+	// Check wintun.dll on Windows
+	if runtime.GOOS == "windows" {
+		exe, _ := os.Executable()
+		exeDir := filepath.Dir(exe)
+		wintunPaths := []string{
+			filepath.Join(exeDir, "wintun.dll"),
+			filepath.Join(*dataDir, "wintun.dll"),
+			"wintun.dll",
+		}
+		found := false
+		for _, p := range wintunPaths {
+			if _, err := os.Stat(p); err == nil {
+				log.Printf("wintun.dll found: %s", p)
+				found = true
+				break
+			}
+		}
+		if !found {
+			log.Printf("WARNING: wintun.dll not found! TUN will fail. Searched: %v", wintunPaths)
+		}
+	}
+
+	app := NewApp(*dataDir, *apiURL)
+
+	log.Println("starting Wails UI")
+	if err := wails.Run(&options.App{
+		Title:     "vpnem",
+		Width:     480,
+		Height:    600,
+		MinWidth:  400,
+		MinHeight: 500,
+		AssetServer: &assetserver.Options{
+			Assets: assets,
+		},
+		OnStartup:  app.startup,
+		OnShutdown: app.shutdown,
+		Bind: []interface{}{
+			app,
+		},
+	}); err != nil {
+		log.Printf("FATAL wails error: %v", err)
+		// On Windows, also write to a visible error file
+		if runtime.GOOS == "windows" {
+			errPath := filepath.Join(*dataDir, "ERROR.txt")
+			os.WriteFile(errPath, []byte("vpnem failed to start:\n"+err.Error()+"\n\nCheck vpnem.log for details.\n"), 0o644)
+		}
+		os.Exit(1)
+	}
+}
+
+func defaultDataDir() string {
+	if runtime.GOOS == "windows" {
+		return `C:\ProgramData\vpnem`
+	}
+	home, _ := os.UserHomeDir()
+	return filepath.Join(home, ".local", "share", "vpnem")
+}