}

// WatcherHandlerRegistration will be returned to caller to remove the handler later.
type WatcherHandlerRegistration struct {
	handler func()
}

// NetworksWatcher watches changes to the mesh networks config.
type NetworksWatcher interface {
	NetworksHolder

	// AddNetworksHandler registers a callback handler for changes to the networks config.
	AddNetworksHandler(func()) *WatcherHandlerRegistration

	if s.environment.NetworksWatcher != nil {
		return
	}
	log.Info("initializing mesh networks")
	if args.NetworksConfigFile != "" {
		var err error
		s.environment.NetworksWatcher, err = mesh.NewNetworksWatcher(fileWatcher, args.NetworksConfigFile)
		if err != nil {
			log.Info(err)
		}
	}

	if s.environment.NetworksWatcher == nil {

	// If provided, the ConfigString will be treated as a go template, with this as input params
	ConfigTemplateInput any
	// If provided, this mesh config will be used
	MeshConfig      *meshconfig.MeshConfig
	NetworksWatcher mesh.NetworksWatcher

	// Callback to modify the kube client before it is started
	KubeClientModifier func(c kubelib.Client)

	// Override the default kube client constructor

	for _, reg := range opts.ServiceRegistries {
		serviceDiscovery.AddRegistry(reg)
	}
	if opts.NetworksWatcher == nil {
		opts.NetworksWatcher = mesh.NewFixedNetworksWatcher(nil)
	}
	env.ServiceDiscovery = serviceDiscovery
	env.ConfigStore = configController
	env.NetworksWatcher = opts.NetworksWatcher
	env.Init()

	fake := &ConfigGenTest{
		t:                    t,
		store:                configController,

)

const (
	defaultFakeDomainSuffix = "company.com"
)

type FakeControllerOptions struct {
	Client            kubelib.Client
	CRDs              []schema.GroupVersionResource
	NetworksWatcher   mesh.NetworksWatcher
	MeshWatcher       mesh.Watcher
	ServiceHandler    model.ServiceHandler
	ClusterID         cluster.ID
	WatchedNamespaces string
	DomainSuffix      string
	XDSUpdater        model.XDSUpdater

	meshNetworks := server.Env().NetworksWatcher.Networks()
	// copy old networks if they exist
	c := map[string]*meshconfig.Network{}
	if meshNetworks != nil {
		for k, v := range meshNetworks.Networks {
			c[k] = v
		}
	}
	// add the new one
	c[string(id)] = network
	server.Env().NetworksWatcher.SetNetworks(&meshconfig.MeshNetworks{Networks: c})
}

	mesh.Watcher

	// NetworksWatcher (loaded from a config map) provides information about the
	// set of networks inside a mesh and how to route to endpoints in each
	// network. Each network provides information about the endpoints in a
	// routable L3 network. A single routable L3 network can have one or more
	// service registries.
	NetworksWatcher mesh.NetworksWatcher

	NetworkManager *NetworkManager

		g.Expect(w.Networks()).To(Equal(newN))
		break
	case <-time.After(time.Second * 5):
		t.Fatal("timed out waiting for update")
	}
}

func newNetworksWatcher(t *testing.T, filename string) mesh.NetworksWatcher {
	t.Helper()
	w, err := mesh.NewNetworksWatcher(filewatcher.NewWatcher(), filename)
	if err != nil {
		t.Fatal(err)
	}
	return w

	test.SetForTest(t, &features.MultiNetworkGatewayAPI, true)
	meshNetworks := mesh.NewFixedNetworksWatcher(nil)
	c, _ := NewFakeControllerWithOptions(t, FakeControllerOptions{
		ClusterID:       constants.DefaultClusterName,
		NetworksWatcher: meshNetworks,
		DomainSuffix:    "cluster.local",
		CRDs:            []schema.GroupVersionResource{gvr.KubernetesGateway},
	})

	if len(c.NetworkGateways()) != 0 {
		t.Fatal("did not expect any gateways yet")
	}

	args.RegistryOptions.KubeOptions.Metrics = s.environment
	args.RegistryOptions.KubeOptions.XDSUpdater = s.XDSServer
	args.RegistryOptions.KubeOptions.MeshNetworksWatcher = s.environment.NetworksWatcher
	args.RegistryOptions.KubeOptions.MeshWatcher = s.environment.Watcher
	args.RegistryOptions.KubeOptions.SystemNamespace = args.Namespace
	args.RegistryOptions.KubeOptions.MeshServiceController = s.ServiceController()