// Add a new service to the Registry.
// Do not replace an existing service.
func (s *ServiceRegistry) AddService(svcCfg client.ServiceConfig) error {
	s.Lock()
	defer s.Unlock()

	log.Debug("Adding service:", svcCfg.Name)
	if _, ok := s.svcs[svcCfg.Name]; ok {
		log.Debug("Service already exists:", svcCfg.Name)
		return ErrDuplicateService
	}

	s.setServiceDefaults(&svcCfg)
	svcCfg = svcCfg.SetDefaults()

	service := NewService(svcCfg)
	err := service.start()
	if err != nil {
		return err
	}

	s.svcs[service.Name] = service

	svcCfg.VirtualHosts = filterEmpty(svcCfg.VirtualHosts)
	for _, name := range svcCfg.VirtualHosts {
		vhost := s.vhosts[name]
		if vhost == nil {
			vhost = &VirtualHost{Name: name}
			s.vhosts[name] = vhost
		}
		vhost.Add(service)
	}

	return nil
}

// Make HTTP calls over the TCP proxy for comparison to ReverseProxy
func BenchmarkTCPProxy(b *testing.B) {
	setupBench(b)
	defer tearDownBench(b)

	svcCfg := client.ServiceConfig{
		Name:         "VHostTest",
		Addr:         "127.0.0.1:9000",
		VirtualHosts: []string{"test-vhost"},
	}

	for _, srv := range benchBackends {
		cfg := client.BackendConfig{
			Addr: srv.addr,
			Name: srv.addr,
		}
		svcCfg.Backends = append(svcCfg.Backends, cfg)
	}

	err := Registry.AddService(svcCfg)
	if err != nil {
		b.Fatal(err)
	}

	req, err := http.NewRequest("GET", "http://127.0.0.1:9000/addr", nil)
	if err != nil {
		b.Fatal(err)
	}

	req.Host = "test-vhost"

	http.DefaultTransport.(*http.Transport).DisableKeepAlives = true
	runtime.GC()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		resp, err := http.DefaultClient.Do(req)
		if err != nil {
			b.Fatal("Error during GET:", err)
		}
		body, err := ioutil.ReadAll(resp.Body)
		resp.Body.Close()
		if err != nil {
			b.Fatal("Error during Read:", err)
		}
		if len(body) < 7 {
			b.Fatalf("Error in Response: %s", body)
		}
	}

	runtime.GC()
}

// set any missing global configuration on a new ServiceConfig.
// ServiceRegistry *must* be locked.
func (s *ServiceRegistry) setServiceDefaults(svc *client.ServiceConfig) {
	if svc.Balance == "" && s.cfg.Balance != "" {
		svc.Balance = s.cfg.Balance
	}
	if svc.CheckInterval == 0 && s.cfg.CheckInterval != 0 {
		svc.CheckInterval = s.cfg.CheckInterval
	}
	if svc.Fall == 0 && s.cfg.Fall != 0 {
		svc.Fall = s.cfg.Fall
	}
	if svc.Rise == 0 && s.cfg.Rise != 0 {
		svc.Rise = s.cfg.Rise
	}
	if svc.ClientTimeout == 0 && s.cfg.ClientTimeout != 0 {
		svc.ClientTimeout = s.cfg.ClientTimeout
	}
	if svc.ServerTimeout == 0 && s.cfg.ServerTimeout != 0 {
		svc.ServerTimeout = s.cfg.ServerTimeout
	}
	if svc.DialTimeout == 0 && s.cfg.DialTimeout != 0 {
		svc.DialTimeout = s.cfg.DialTimeout
	}
	if s.cfg.HTTPSRedirect {
		svc.HTTPSRedirect = true
	}
}

func (s *HTTPSuite) TestErrorPage(c *C) {
	svcCfg := client.ServiceConfig{
		Name:         "VHostTest",
		Addr:         "127.0.0.1:9000",
		VirtualHosts: []string{"test-vhost"},
	}

	okServer := s.backendServers[0]
	errServer := s.backendServers[1]

	// Add one backend to service requests
	cfg := client.BackendConfig{
		Addr: okServer.addr,
		Name: okServer.addr,
	}
	svcCfg.Backends = append(svcCfg.Backends, cfg)

	// use another backend to provide the error page
	svcCfg.ErrorPages = map[string][]int{
		"http://" + errServer.addr + "/error": []int{400, 503},
	}

	err := Registry.AddService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	// check that the normal response comes from srv1
	checkHTTP("http://"+s.httpAddr+"/addr", "test-vhost", okServer.addr, 200, c)
	// verify that an unregistered error doesn't give the cached page
	checkHTTP("http://"+s.httpAddr+"/error?code=504", "test-vhost", okServer.addr, 504, c)
	// now see if the registered error comes from srv2
	checkHTTP("http://"+s.httpAddr+"/error?code=503", "test-vhost", errServer.addr, 503, c)

	// now check that we got the header cached in the error page as well
	req, err := http.NewRequest("GET", "http://"+s.httpAddr+"/error?code=503", nil)
	if err != nil {
		c.Fatal(err)
	}

	req.Host = "test-vhost"
	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		c.Fatal(err)
	}

	c.Assert(resp.StatusCode, Equals, 503)
	c.Assert(resp.Header.Get("Last-Modified"), Equals, errServer.addr)
}

func (s *HTTPSuite) TestSimulAdd(c *C) {
	start := make(chan struct{})
	testWG := new(sync.WaitGroup)

	svcCfg := client.ServiceConfig{
		Name:         "TestService",
		Addr:         "127.0.0.1:9000",
		VirtualHosts: []string{"test-vhost"},
		Backends: []client.BackendConfig{
			client.BackendConfig{
				Name: "vhost1",
				Addr: "127.0.0.1:9001",
			},
			client.BackendConfig{
				Name: "vhost2",
				Addr: "127.0.0.1:9002",
			},
		},
	}

	for i := 0; i < 8; i++ {
		testWG.Add(1)
		go func() {
			defer testWG.Done()
			//wait to start all at once
			<-start
			svcDef := bytes.NewReader(svcCfg.Marshal())
			req, _ := http.NewRequest("PUT", s.httpSvr.URL+"/TestService", svcDef)
			resp, err := http.DefaultClient.Do(req)
			if err != nil {
				c.Fatal(err)
			}

			body, _ := ioutil.ReadAll(resp.Body)

			respCfg := client.Config{}
			err = json.Unmarshal(body, &respCfg)

			// We're only checking to ensure we have 1 service with the proper number of backends
			c.Assert(len(respCfg.Services), Equals, 1)
			c.Assert(len(respCfg.Services[0].Backends), Equals, 2)
			c.Assert(len(respCfg.Services[0].VirtualHosts), Equals, 1)
		}()
	}

	close(start)
	testWG.Wait()
}

func (s *HTTPSuite) TestAddRemoveVHosts(c *C) {
	svcCfg := client.ServiceConfig{
		Name:         "VHostTest",
		Addr:         "127.0.0.1:9000",
		VirtualHosts: []string{"test-vhost"},
	}

	for _, srv := range s.backendServers {
		cfg := client.BackendConfig{
			Addr: srv.addr,
			Name: srv.addr,
		}
		svcCfg.Backends = append(svcCfg.Backends, cfg)
	}

	err := Registry.AddService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	// now update the service with another vhost
	svcCfg.VirtualHosts = append(svcCfg.VirtualHosts, "test-vhost-2")
	err = Registry.UpdateService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	if Registry.VHostsLen() != 2 {
		c.Fatal("missing new vhost")
	}

	// remove the first vhost
	svcCfg.VirtualHosts = []string{"test-vhost-2"}
	err = Registry.UpdateService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	if Registry.VHostsLen() != 1 {
		c.Fatal("extra vhost:", Registry.VHostsLen())
	}

	// check responses from this new vhost
	for _, srv := range s.backendServers {
		checkHTTP("http://"+s.httpAddr+"/addr", "test-vhost-2", srv.addr, 200, c)
	}
}

// Set some global defaults, and check that a new service inherits them all
func (s *HTTPSuite) TestGlobalDefaults(c *C) {
	globalCfg := client.Config{
		Balance:       "LC",
		CheckInterval: 101,
		Fall:          7,
		Rise:          8,
		ClientTimeout: 102,
		ServerTimeout: 103,
		DialTimeout:   104,
	}

	globalDef := bytes.NewBuffer(globalCfg.Marshal())
	req, _ := http.NewRequest("PUT", s.httpSvr.URL+"/", globalDef)
	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		c.Fatal(err)
	}
	resp.Body.Close()

	svcCfg := client.ServiceConfig{
		Name: "TestService",
		Addr: "127.0.0.1:9000",
	}

	svcDef := bytes.NewBuffer(svcCfg.Marshal())
	req, _ = http.NewRequest("PUT", s.httpSvr.URL+"/TestService", svcDef)
	resp, err = http.DefaultClient.Do(req)
	if err != nil {
		c.Fatal(err)
	}
	resp.Body.Close()

	config := Registry.Config()

	c.Assert(len(config.Services), Equals, 1)
	service := config.Services[0]

	c.Assert(globalCfg.Balance, Equals, service.Balance)
	c.Assert(globalCfg.CheckInterval, Equals, service.CheckInterval)
	c.Assert(globalCfg.Fall, Equals, service.Fall)
	c.Assert(globalCfg.Rise, Equals, service.Rise)
	c.Assert(globalCfg.ClientTimeout, Equals, service.ClientTimeout)
	c.Assert(globalCfg.ServerTimeout, Equals, service.ServerTimeout)
	c.Assert(globalCfg.DialTimeout, Equals, service.DialTimeout)
}

// Add multiple services under the same VirtualHost
// Each proxy request should round-robin through the two of them
func (s *HTTPSuite) TestMultiServiceVHost(c *C) {
	svcCfgOne := client.ServiceConfig{
		Name:         "VHostTest",
		Addr:         "127.0.0.1:9000",
		VirtualHosts: []string{"test-vhost"},
	}

	svcCfgTwo := client.ServiceConfig{
		Name:         "VHostTest2",
		Addr:         "127.0.0.1:9001",
		VirtualHosts: []string{"test-vhost-2"},
	}

	var backends []client.BackendConfig
	for _, srv := range s.backendServers {
		cfg := client.BackendConfig{
			Addr: srv.addr,
			Name: srv.addr,
		}
		backends = append(backends, cfg)
	}

	svcCfgOne.Backends = backends
	svcCfgTwo.Backends = backends

	err := Registry.AddService(svcCfgOne)
	if err != nil {
		c.Fatal(err)
	}

	err = Registry.AddService(svcCfgTwo)
	if err != nil {
		c.Fatal(err)
	}

	for _, srv := range s.backendServers {
		checkHTTP("http://"+s.httpAddr+"/addr", "test-vhost", srv.addr, 200, c)
		checkHTTP("http://"+s.httpAddr+"/addr", "test-vhost-2", srv.addr, 200, c)
	}
}

func (s *BasicSuite) TestInvalidUpdateService(c *C) {
	svcCfg := client.ServiceConfig{
		Name: "Update",
		Addr: "127.0.0.1:9324",
	}

	if err := Registry.AddService(svcCfg); err != nil {
		c.Fatal(err)
	}

	svc := Registry.GetService("Update")
	if svc == nil {
		c.Fatal(ErrNoService)
	}

	svcCfg.Addr = "127.0.0.1:9425"

	// Make sure we can't add the same service again
	if err := Registry.AddService(svcCfg); err == nil {
		c.Fatal(err)
	}

	// the update should fail, because it would require a new listener
	if err := Registry.UpdateService(svcCfg); err == nil {
		c.Fatal(err)
	}

	// change the addres back, and try to update ClientTimeout
	svcCfg.Addr = "127.0.0.1:9324"
	svcCfg.ClientTimeout = 1234

	// the update should fail, because it would require a new listener
	if err := Registry.UpdateService(svcCfg); err == nil {
		c.Fatal(err)
	}

	if err := Registry.RemoveService("Update"); err != nil {
		c.Fatal(err)
	}
}

func (s *Service) config() client.ServiceConfig {

	config := client.ServiceConfig{
		Name:          s.Name,
		Addr:          s.Addr,
		VirtualHosts:  s.VirtualHosts,
		HTTPSRedirect: s.HTTPSRedirect,
		Balance:       s.Balance,
		CheckInterval: s.CheckInterval,
		Fall:          s.Fall,
		Rise:          s.Rise,
		ClientTimeout: int(s.ClientTimeout / time.Millisecond),
		ServerTimeout: int(s.ServerTimeout / time.Millisecond),
		DialTimeout:   int(s.DialTimeout / time.Millisecond),
		ErrorPages:    s.errPagesCfg,
		Network:       s.Network,
	}
	for _, b := range s.Backends {
		config.Backends = append(config.Backends, b.Config())
	}

	return config
}

func (s *HTTPSuite) TestRouter(c *C) {
	svcCfg := client.ServiceConfig{
		Name:         "VHostTest",
		Addr:         "127.0.0.1:9000",
		VirtualHosts: []string{"test-vhost"},
	}

	for _, srv := range s.backendServers {
		cfg := client.BackendConfig{
			Addr: srv.addr,
			Name: srv.addr,
		}
		svcCfg.Backends = append(svcCfg.Backends, cfg)
	}

	err := Registry.AddService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	for _, srv := range s.backendServers {
		checkHTTP("http://"+s.httpAddr+"/addr", "test-vhost", srv.addr, 200, c)
	}
}

func (s *HTTPSuite) TestUpdateServiceDefaults(c *C) {
	svcCfg := client.ServiceConfig{
		Name: "TestService",
		Addr: "127.0.0.1:9000",
		Backends: []client.BackendConfig{
			client.BackendConfig{
				Name: "Backend1",
				Addr: "127.0.0.1:9001",
			},
		},
	}

	svcDef := bytes.NewBuffer(svcCfg.Marshal())
	req, _ := http.NewRequest("PUT", s.httpSvr.URL+"/TestService", svcDef)
	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		c.Fatal(err)
	}
	resp.Body.Close()

	// Now update the Service in-place
	svcCfg.ServerTimeout = 1234
	svcDef.Reset()
	svcDef.Write(svcCfg.Marshal())

	req, _ = http.NewRequest("PUT", s.httpSvr.URL+"/TestService", svcDef)
	resp, err = http.DefaultClient.Do(req)
	if err != nil {
		c.Fatal(err)
	}

	body, _ := ioutil.ReadAll(resp.Body)
	resp.Body.Close()

	config := client.Config{}
	err = json.Unmarshal(body, &config)
	if err != nil {
		c.Fatal(err)
	}

	// make sure we don't see a second value
	found := false

	for _, svc := range config.Services {
		if svc.Name == "TestService" {
			if svc.ServerTimeout != svcCfg.ServerTimeout {
				c.Fatal("Service not updated")
			} else if found {
				c.Fatal("Multiple Service Definitions")
			}
			found = true
		}
	}
}

func (s *HTTPSuite) TestAddRemoveBackends(c *C) {
	svcCfg := client.ServiceConfig{
		Name: "VHostTest",
		Addr: "127.0.0.1:9000",
	}

	err := Registry.AddService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	for _, srv := range s.backendServers {
		cfg := client.BackendConfig{
			Addr: srv.addr,
			Name: srv.addr,
		}
		svcCfg.Backends = append(svcCfg.Backends, cfg)
	}

	err = Registry.UpdateService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	cfg := Registry.Config()
	if !svcCfg.DeepEqual(cfg.Services[0]) {
		c.Errorf("we should have 1 service, we have %d", len(cfg.Services))
		c.Errorf("we should have 4 backends, we have %d", len(cfg.Services[0].Backends))
	}

	svcCfg.Backends = svcCfg.Backends[:3]
	err = Registry.UpdateService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	cfg = Registry.Config()
	if !svcCfg.DeepEqual(cfg.Services[0]) {
		c.Errorf("we should have 1 service, we have %d", len(cfg.Services))
		c.Errorf("we should have 3 backends, we have %d", len(cfg.Services[0].Backends))
	}

}

// check valid service updates
func (s *BasicSuite) TestUpdateService(c *C) {
	svcCfg := client.ServiceConfig{
		Name: "Update2",
		Addr: "127.0.0.1:9324",
	}

	if err := Registry.AddService(svcCfg); err != nil {
		c.Fatal(err)
	}

	svc := Registry.GetService("Update2")
	if svc == nil {
		c.Fatal(ErrNoService)
	}

	svcCfg.ServerTimeout = 1234
	svcCfg.HTTPSRedirect = true
	svcCfg.Fall = 5
	svcCfg.Rise = 6
	svcCfg.Balance = "LC"

	// Now update the service for real
	if err := Registry.UpdateService(svcCfg); err != nil {
		c.Fatal(err)
	}

	svc = Registry.GetService("Update2")
	if svc == nil {
		c.Fatal(ErrNoService)
	}
	c.Assert(svc.ServerTimeout, Equals, 1234*time.Millisecond)
	c.Assert(svc.HTTPSRedirect, Equals, true)
	c.Assert(svc.Fall, Equals, 5)
	c.Assert(svc.Rise, Equals, 6)
	c.Assert(svc.Balance, Equals, "LC")

	if err := Registry.RemoveService("Update2"); err != nil {
		c.Fatal(err)
	}
}

func (s *HTTPSuite) TestHTTPAddRemoveBackends(c *C) {
	svcCfg := client.ServiceConfig{
		Name: "VHostTest",
		Addr: "127.0.0.1:9000",
	}

	err := Registry.AddService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	for _, srv := range s.backendServers {
		cfg := client.BackendConfig{
			Addr: srv.addr,
			Name: srv.addr,
		}
		svcCfg.Backends = append(svcCfg.Backends, cfg)
	}

	req, _ := http.NewRequest("PUT", s.httpSvr.URL+"/VHostTest", bytes.NewReader(svcCfg.Marshal()))
	_, err = http.DefaultClient.Do(req)
	if err != nil {
		c.Fatal(err)
	}

	cfg := Registry.Config()
	if !svcCfg.DeepEqual(cfg.Services[0]) {
		c.Errorf("we should have 1 service, we have %d", len(cfg.Services))
		c.Errorf("we should have 4 backends, we have %d", len(cfg.Services[0].Backends))
	}

	// remove a backend from the config and submit it again
	svcCfg.Backends = svcCfg.Backends[:3]
	err = Registry.UpdateService(svcCfg)
	if err != nil {
		c.Fatal(err)
	}

	req, _ = http.NewRequest("PUT", s.httpSvr.URL+"/VHostTest", bytes.NewReader(svcCfg.Marshal()))
	_, err = http.DefaultClient.Do(req)
	if err != nil {
		c.Fatal(err)
	}

	// now check the config via what's returned from the http server
	resp, err := http.Get(s.httpSvr.URL + "/_config")
	if err != nil {
		c.Fatal(err)
	}
	defer resp.Body.Close()

	cfg = client.Config{}
	body, _ := ioutil.ReadAll(resp.Body)
	err = json.Unmarshal(body, &cfg)
	if err != nil {
		c.Fatal(err)
	}

	if !svcCfg.DeepEqual(cfg.Services[0]) {
		c.Errorf("we should have 1 service, we have %d", len(cfg.Services))
		c.Errorf("we should have 3 backends, we have %d", len(cfg.Services[0].Backends))
	}
}

// Replace the service's configuration, or update its list of backends.
// Replacing a configuration will shutdown the existing service, and start a
// new one, which will cause the listening socket to be temporarily
// unavailable.
func (s *ServiceRegistry) UpdateService(newCfg client.ServiceConfig) error {
	s.Lock()
	defer s.Unlock()

	log.Debug("Updating Service:", newCfg.Name)
	service, ok := s.svcs[newCfg.Name]
	if !ok {
		log.Debug("Service not found:", newCfg.Name)
		return ErrNoService
	}

	currentCfg := service.Config()
	newCfg.Merge(currentCfg)

	if err := service.UpdateConfig(newCfg); err != nil {
		return err
	}

	// Lots of looping here (including fetching the Config, but the cardinality
	// of Backends shouldn't be very large, and the default RoundRobin balancing
	// is much simpler with a slice.

	// we're going to update just the backends for this config
	// get a map of what's already running
	currentBackends := make(map[string]client.BackendConfig)
	for _, backendCfg := range currentCfg.Backends {
		currentBackends[backendCfg.Name] = backendCfg
	}

	// Keep existing backends when they have equivalent config.
	// Update changed backends, and add new ones.
	for _, newBackend := range newCfg.Backends {
		current, ok := currentBackends[newBackend.Name]
		if ok && current.Equal(newBackend) {
			log.Debugf("Backend %s/%s unchanged", service.Name, current.Name)
			// no change for this one
			delete(currentBackends, current.Name)
			continue
		}

		// we need to remove and re-add this backend
		log.Debugf("Updating Backend %s/%s", service.Name, newBackend.Name)
		service.remove(newBackend.Name)
		service.add(NewBackend(newBackend))

		delete(currentBackends, newBackend.Name)
	}

	// remove any left over backends
	for name := range currentBackends {
		log.Debugf("Removing Backend %s/%s", service.Name, name)
		service.remove(name)
	}

	if currentCfg.Equal(newCfg) {
		log.Debugf("Service Unchanged %s", service.Name)
		return nil
	}

	// replace error pages if there's any change
	if !reflect.DeepEqual(service.errPagesCfg, newCfg.ErrorPages) {
		log.Debugf("Updating ErrorPages")
		service.errPagesCfg = newCfg.ErrorPages
		service.errorPages.Update(newCfg.ErrorPages)
	}

	s.updateVHosts(service, filterEmpty(newCfg.VirtualHosts))

	return nil
}