package server

import (
	"crypto/rand"
	"encoding/hex"
	"fmt"
	"log/slog"
	"net"
)

// GetLANIP returns the first non-loopback IPv4 address.
func GetLANIP() (string, error) {
	addrs, err := net.InterfaceAddrs()
	if err != nil {
		return "", err
	}
	for _, addr := range addrs {
		if ipNet, ok := addr.(*net.IPNet); ok && !ipNet.IP.IsLoopback() && ipNet.IP.To4() != nil {
			return ipNet.IP.String(), nil
		}
	}
	return "", fmt.Errorf("no LAN IP found")
}

// GenerateToken creates a cryptographically random token for WS auth.
func GenerateToken() string {
	b := make([]byte, 16)
	if _, err := rand.Read(b); err != nil {
		slog.Error("failed to generate token", "error", err)
		// Fallback to a less secure but functional token
		return "voicepaste-fallback-token"
	}
	return hex.EncodeToString(b)
}