/*
	Copyright NetFoundry Inc.

	Licensed under the Apache License, Version 2.0 (the "License");
	you may not use this file except in compliance with the License.
	You may obtain a copy of the License at

	https://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
*/

package controller

import (
	"bytes"
	"compress/gzip"
	cryptoTls "crypto/tls"
	"crypto/x509"
	"encoding/json"
	"fmt"
	"os"
	"strings"
	"sync"
	"sync/atomic"

	gosundheit "github.com/AppsFlyer/go-sundheit"
	"github.com/michaelquigley/pfxlog"
	"github.com/openziti/channel/v4"
	"github.com/openziti/channel/v4/protobufs"
	"github.com/openziti/foundation/v2/concurrenz"
	"github.com/openziti/foundation/v2/versions"
	"github.com/openziti/identity"
	"github.com/openziti/metrics"
	"github.com/openziti/ziti/v2/controller/storage/boltz"
	"github.com/openziti/transport/v2"
	"github.com/openziti/transport/v2/tls"
	"github.com/openziti/xweb/v3"
	"github.com/openziti/ziti/v2/common/bindpoints"
	"github.com/openziti/ziti/v2/common/capabilities"
	"github.com/openziti/ziti/v2/common/concurrency"
	fabricMetrics "github.com/openziti/ziti/v2/common/metrics"
	"github.com/openziti/ziti/v2/common/pb/ctrl_pb"
	"github.com/openziti/ziti/v2/common/profiler"
	"github.com/openziti/ziti/v2/controller/command"
	"github.com/openziti/ziti/v2/controller/config"
	"github.com/openziti/ziti/v2/controller/db"
	"github.com/openziti/ziti/v2/controller/env"
	"github.com/openziti/ziti/v2/controller/event"
	"github.com/openziti/ziti/v2/controller/events"
	"github.com/openziti/ziti/v2/controller/handler_ctrl"
	"github.com/openziti/ziti/v2/controller/handler_peer_ctrl"
	"github.com/openziti/ziti/v2/controller/network"
	"github.com/openziti/ziti/v2/controller/raft"
	"github.com/openziti/ziti/v2/controller/raft/mesh"
	"github.com/openziti/ziti/v2/controller/webapis"
	"github.com/openziti/ziti/v2/controller/xctrl"
	"github.com/openziti/ziti/v2/controller/xmgmt"
	"github.com/openziti/ziti/v2/controller/xt"
	"github.com/openziti/ziti/v2/controller/xt_random"
	"github.com/openziti/ziti/v2/controller/xt_smartrouting"
	"github.com/openziti/ziti/v2/controller/xt_sticky"
	"github.com/openziti/ziti/v2/controller/xt_weighted"
	"github.com/pkg/errors"
	"github.com/sirupsen/logrus"
	"github.com/teris-io/shortid"
	"go.etcd.io/bbolt"
)

type Controller struct {
	config             *config.Config
	env                *env.AppEnv
	network            *network.Network
	raftController     *raft.Controller
	localDispatcher    *command.LocalDispatcher
	ctrlConnectHandler *handler_ctrl.ConnectHandler
	xctrls             []xctrl.Xctrl
	xmgmts             concurrenz.CopyOnWriteSlice[xmgmt.Xmgmt]

	xwebFactoryRegistry xweb.Registry
	xweb                xweb.Instance

	ctrlListener channel.UnderlayListener
	mgmtListener channel.UnderlayListener

	shutdownC         chan struct{}
	isShutdown        atomic.Bool
	agentBindHandlers []channel.BindHandler
	metricsRegistry   metrics.Registry
	versionProvider   versions.VersionProvider
	eventDispatcher   *events.Dispatcher

	apiData      map[string][]event.ApiAddress
	apiDataBytes []byte
	apiDataOnce  sync.Once

	xwebInitialized concurrency.InitState
	healthChecker   gosundheit.Health
}

func init() {
	xweb.BindPointListenerFactoryRegistry = append(xweb.BindPointListenerFactoryRegistry, &bindpoints.BindPointListenerFactory{})
}

func (c *Controller) GetPeerSigners() []*x509.Certificate {
	if c.raftController == nil || c.raftController.Mesh == nil {
		return nil
	}

	var certs []*x509.Certificate

	for _, peer := range c.raftController.Mesh.GetPeers() {
		certs = append(certs, peer.SigningCerts...)
	}

	return certs
}

func (c *Controller) GetPeerAddresses() []string {
	if c.raftController == nil || c.raftController.Mesh == nil {
		return nil
	}

	var addresses []string

	for _, peer := range c.raftController.Mesh.GetPeers() {
		addresses = append(addresses, peer.Address)
	}

	return addresses

}

func (c *Controller) GetId() *identity.TokenId {
	return c.config.Id
}

func (c *Controller) GetConfig() *config.Config {
	return c.config
}

func (c *Controller) GetMetricsRegistry() metrics.Registry {
	return c.metricsRegistry
}

func (c *Controller) GetOptions() *config.NetworkConfig {
	return c.config.Network
}

func (c *Controller) GetCommandDispatcher() command.Dispatcher {
	if c.raftController == nil {
		if c.localDispatcher != nil {
			return c.localDispatcher
		}
		devVersion := versions.MustParseSemVer("0.0.0")
		version := versions.MustParseSemVer(c.GetVersionProvider().Version())
		c.localDispatcher = &command.LocalDispatcher{
			EncodeDecodeCommands: devVersion.Equals(version),
			Limiter:              command.NewRateLimiter(c.config.Command.RateLimiter, c.metricsRegistry, c.shutdownC),
		}
		return c.localDispatcher
	}
	return c.raftController
}

func (c *Controller) IsRaftEnabled() bool {
	return c.raftController != nil
}

func (c *Controller) IsRaftLeader() bool {
	if c.raftController == nil {
		return false
	}
	return c.raftController.IsLeader()
}

func (c *Controller) GetRaftIndex() uint64 {
	return c.raftController.Raft.LastIndex()
}

func (c *Controller) GetStartRaftIndex() uint64 {
	return c.raftController.Fsm.GetStartIndex()
}

func (c *Controller) GetRaftInfo() (string, string, string) {
	id := c.config.Id.Token
	addr := c.raftController.Mesh.Addr().String()

	version := c.GetVersionProvider().Version()

	return addr, id, version
}

func (c *Controller) GetDb() boltz.Db {
	return c.config.Db
}

func (c *Controller) GetVersionProvider() versions.VersionProvider {
	return c.versionProvider
}

func (c *Controller) GetCloseNotify() <-chan struct{} {
	return c.shutdownC
}

func (c *Controller) GetRaftConfig() *config.RaftConfig {
	return c.config.Raft
}

func (c *Controller) GetRaftRateLimiterConfig() command.AdaptiveRateLimitTrackerConfig {
	return c.config.Raft.RateLimiter
}

func (c *Controller) RenderJsonConfig() (string, error) {
	return c.config.ToJson()
}

func (c *Controller) GetEnv() *env.AppEnv {
	return c.env
}

func NewController(cfg *config.Config, versionProvider versions.VersionProvider) (*Controller, error) {
	metricRegistry := metrics.NewRegistry(cfg.Id.Token, nil)

	shutdownC := make(chan struct{})

	tlsHandshakeRateLimiter := command.NewAdaptiveRateLimitTracker(cfg.TlsHandshakeRateLimiter, metricRegistry, shutdownC)
	tls.SetSharedListenerRateLimiter(tlsHandshakeRateLimiter)

	log := pfxlog.Logger()

	c := &Controller{
		config:              cfg,
		shutdownC:           shutdownC,
		xwebFactoryRegistry: xweb.NewRegistryMap(),
		metricsRegistry:     metricRegistry,
		versionProvider:     versionProvider,
		eventDispatcher:     events.NewDispatcher(shutdownC),
		xwebInitialized:     concurrency.NewInitState(),
	}
	xwebInstanceOptions := xweb.InstanceOptions{
		DefaultIdentity:        c.config.Id,
		DefaultIdentitySection: xweb.DefaultIdentitySection,
		DefaultConfigSection:   xweb.DefaultConfigSection,
		InstanceValidators: []xweb.InstanceValidator{
			c.ensureOidcOnClientApiServer,
		},
		ServerMutators: []xweb.ServerMutator{
			func(instance xweb.Instance, serverConfig *xweb.ServerConfig, server *xweb.Server) error {
				for _, httpServer := range server.HttpServers {
					serverTlsConfig := httpServer.TLSConfig.Clone()

					prev := serverTlsConfig.GetConfigForClient
					httpServer.TLSConfig.GetConfigForClient = func(info *cryptoTls.ClientHelloInfo) (*cryptoTls.Config, error) {
						result := serverTlsConfig

						//use inner GetConfigForClient if it was defined
						if prev != nil {
							var err error
							result, err = prev(info)

							if err != nil {
								return nil, err
							}
						}

						result.ClientCAs = c.env.GetManagers().Ca.GetTrustCache().GetAllPool()

						return result, nil
					}
				}
				return nil
			},
		},
	}

	c.xweb = xweb.NewInstance(c.xwebFactoryRegistry, xwebInstanceOptions)

	if cfg.IsRaftEnabled() {
		c.raftController = raft.NewController(c, c)
		if err := c.raftController.Init(); err != nil {
			log.WithError(err).Panic("error starting raft")
		}

		cfg.Db = c.raftController.GetDb()
	}

	c.registerXts()

	appEnv, err := env.NewAppEnv(c)
	if err != nil {
		return nil, err
	}

	c.env = appEnv

	if n, err := network.NewNetwork(c, appEnv); err == nil {
		c.network = n
	} else {
		return nil, err
	}

	if c.raftController != nil {
		if err = c.raftController.InitEnv(c.env); err != nil {
			return nil, err
		}
	}

	c.initWeb() // need to init web before bootstrapping, so we can provide our endpoints to peers

	if c.raftController != nil {
		_, dbConfigured := c.config.Src["db"]
		if c.raftController.IsBootstrapped() {
			// On a clustered config 'db' only seeds a new cluster on first bootstrap; once
			// initialized it is dead config, so warn rather than let a stale setting sit unnoticed.
			if dbConfigured {
				log.Warn("'db' is set but this clustered controller is already initialized; the 'db' setting is ignored and should be removed from the configuration")
			}
		} else if err = c.TryInitializeRaftFromBoltDb(); err != nil {
			log.WithError(err).Panic("error bootstrapping raft")
		}
	}

	c.eventDispatcher.InitializeNetworkEvents(c.network)

	if cfg.Ctrl.Options.NewListener != nil {
		c.network.AddRouterPresenceHandler(&OnConnectSettingsHandler{
			config: cfg,
			settings: map[int32][]byte{
				int32(ctrl_pb.SettingTypes_NewCtrlAddress): []byte((*cfg.Ctrl.Options.NewListener).String()),
			},
		})
	}

	if c.raftController != nil {
		logrus.Info("Adding router presence handler to send out ctrl addresses")
		c.network.AddRouterPresenceHandler(
			NewOnConnectCtrlAddressesUpdateHandler(c.config.Ctrl.Listener.String(), c.raftController),
		)
	}

	if err := c.showOptions(); err != nil {
		return nil, err
	}

	return c, nil
}

func (c *Controller) InitTimelineId(timelineId string) {
	c.env.InitTimelineId(timelineId)
}

func (c *Controller) TimelineId() string {
	return c.env.TimelineId()
}

func (c *Controller) initWeb() {
	healthChecker, err := c.initializeHealthChecks()
	if err != nil {
		logrus.WithError(err).Fatalf("failed to create health checker")
	}
	c.healthChecker = healthChecker

	if err = c.xweb.GetRegistry().Add(webapis.NewControllerHealthCheckApiFactory(c.env, healthChecker)); err != nil {
		logrus.WithError(err).Fatalf("failed to create health checks api factory")
	}

	fabricManagementFactory := webapis.NewFabricManagementApiFactory(c.config.Id, c.env, c.network, &c.xmgmts)
	if err = c.xweb.GetRegistry().Add(fabricManagementFactory); err != nil {
		logrus.WithError(err).Fatalf("failed to create management api factory")
	}

	if err = c.xweb.GetRegistry().Add(webapis.NewMetricsApiFactory(c.config.Id, c.network)); err != nil {
		logrus.WithError(err).Fatalf("failed to create metrics api factory")
	}

	if err = c.xweb.GetRegistry().Add(webapis.NewSpaFactory()); err != nil {
		logrus.WithError(err).Fatalf("failed to create single page application factory")
	}

	// Back-compat: preserve the legacy `binding: zac` so existing controller configs keep working.
	// New configs should use `binding: spa` with an explicit `path`.
	if err = c.xweb.GetRegistry().Add(webapis.NewZitiAdminConsoleFactory()); err != nil {
		logrus.WithError(err).Fatalf("failed to create legacy ZAC factory")
	}

	if c.IsEdgeEnabled() {
		managementApiFactory := webapis.NewManagementApiFactory(c.env)
		clientApiFactory := webapis.NewClientApiFactory(c.env)
		oidcApiFactory := webapis.NewOidcApiFactory(c.env)

		if err = c.xweb.GetRegistry().Add(managementApiFactory); err != nil {
			pfxlog.Logger().Fatalf("failed to create Edge Management API factory: %v", err)
		}

		if err = c.xweb.GetRegistry().Add(clientApiFactory); err != nil {
			pfxlog.Logger().Fatalf("failed to create Edge Client API factory: %v", err)
		}

		if err = c.xweb.GetRegistry().Add(oidcApiFactory); err != nil {
			pfxlog.Logger().Fatalf("failed to create OIDC API factory: %v", err)
		}
	} else {
		// if no edge  we need 1 default API, make the fabric api the default
		fabricManagementFactory.MakeDefault = true
	}
}

func (c *Controller) IsEdgeEnabled() bool {
	return c.config.Edge.Enabled
}

// ensureOidcOnClientApiServer is an xweb InstanceValidator that automatically co-locates the edge OIDC
// API on the same web listener as the edge client API when the OIDC API is not explicitly configured
// anywhere. Selection prefers the web listener whose bind point address matches edge.api.address. If
// no bind point matches and there is only one edge-client web listener, OIDC is added there with a
// warning. If multiple edge-client web listeners exist and none match, OIDC is added to all of them
// with a warning.
func (c *Controller) ensureOidcOnClientApiServer(instanceConfig *xweb.InstanceConfig) error {
	if !c.IsEdgeEnabled() {
		return nil
	}

	if c.config.Edge.Api.DisableOidcAutoBinding {
		return nil
	}

	for _, serverConfig := range instanceConfig.ServerConfigs {
		for _, api := range serverConfig.APIs {
			if api.Binding() == webapis.OidcApiBinding {
				return nil
			}
		}
	}

	edgeApiAddress := c.config.Edge.Api.Address

	addOidc := func(serverConfig *xweb.ServerConfig) error {
		oidcApiConfig := &xweb.ApiConfig{}
		if err := oidcApiConfig.Parse(map[interface{}]interface{}{
			"binding": webapis.OidcApiBinding,
		}); err != nil {
			return fmt.Errorf("could not auto-configure edge OIDC API: %w", err)
		}
		serverConfig.APIs = append(serverConfig.APIs, oidcApiConfig)
		return nil
	}

	var addressMatchedServers []*xweb.ServerConfig
	var clientApiServers []*xweb.ServerConfig

	for _, serverConfig := range instanceConfig.ServerConfigs {
		hasClientApi := false
		for _, api := range serverConfig.APIs {
			if api.Binding() == webapis.ClientApiBinding {
				hasClientApi = true
				break
			}
		}
		if !hasClientApi {
			continue
		}
		clientApiServers = append(clientApiServers, serverConfig)
		for _, bp := range serverConfig.BindPoints {
			if bp.ServerAddress() == edgeApiAddress {
				addressMatchedServers = append(addressMatchedServers, serverConfig)
				break
			}
		}
	}

	if len(addressMatchedServers) > 0 {
		for _, serverConfig := range addressMatchedServers {
			if err := addOidc(serverConfig); err != nil {
				return err
			}
			pfxlog.Logger().Infof("edge OIDC API not explicitly configured; automatically added to '%s' web listener", serverConfig.Name)
		}
		return nil
	}

	switch len(clientApiServers) {
	case 0:
		return nil
	case 1:
		if err := addOidc(clientApiServers[0]); err != nil {
			return err
		}
		pfxlog.Logger().Warnf("edge OIDC API not explicitly configured; no edge-client bind point matched [edge.api.address] value [%s]; automatically added to '%s' web listener", edgeApiAddress, clientApiServers[0].Name)
	default:
		for _, serverConfig := range clientApiServers {
			if err := addOidc(serverConfig); err != nil {
				return err
			}
		}
		var names []string
		for _, s := range clientApiServers {
			names = append(names, "'"+s.Name+"'")
		}
		pfxlog.Logger().Warnf("edge OIDC API not explicitly configured; no edge-client bind point matched [edge.api.address] value [%s]; automatically added to all edge-client web listeners: %s", edgeApiAddress, strings.Join(names, ", "))
	}

	return nil
}

func (c *Controller) Run() error {
	c.startProfiling()

	if err := c.registerComponents(); err != nil {
		return fmt.Errorf("error registering component: %s", err)
	}
	versionInfo := c.network.VersionProvider.AsVersionInfo()
	versionHeader, err := c.network.VersionProvider.EncoderDecoder().Encode(versionInfo)

	if err != nil {
		pfxlog.Logger().Panicf("could not prepare version headers: %v", err)
	}

	capabilityMask := capabilities.GetControllerCapabilitiesMask()

	headers := map[int32][]byte{
		channel.HelloVersionHeader:                       versionHeader,
		int32(ctrl_pb.ControlHeaders_CapabilitiesHeader): capabilityMask.Bytes(),
		ctrl_pb.LegacyCapabilitiesHeader:                 capabilityMask.Bytes(), // for pre-2.0 routers
	}

	/**
	 * ctrl listener/accepter.
	 */
	ctrlChannelListenerConfig := channel.ListenerConfig{
		ConnectOptions:   c.config.Ctrl.Options.ConnectOptions,
		PoolConfigurator: fabricMetrics.GoroutinesPoolMetricsConfigF(c.network.GetMetricsRegistry(), "pool.listener.ctrl"),
		Headers:          headers,
		TransportConfig:  transport.Configuration{"protocol": "ziti-ctrl"},
	}

	if c.raftController != nil {
		ctrlChannelListenerConfig.HeadersF = c.raftController.GetListenerHeaders
	}

	pfxlog.Logger().Infof("staring control channel listener on %s", c.config.Ctrl.Listener.String())
	ctrlListener := channel.NewClassicListener(c.config.Id, c.config.Ctrl.Listener, ctrlChannelListenerConfig)
	c.ctrlListener = ctrlListener

	ctrlAccepter := handler_ctrl.NewCtrlAccepter(c.network, c.xctrls, c.config.Ctrl.Options.Options, c.config.Ctrl.Options.RouterHeartbeatOptions, c.config.Trace.Handler)

	ctrlAcceptors := map[string]channel.UnderlayAcceptor{}
	if c.raftController != nil {
		c.raftController.ConfigureMeshHandlers(handler_peer_ctrl.NewBindHandler(c.network, c.raftController, c.config.Ctrl.Options.PeerHeartbeatOptions))
		ctrlAcceptors[mesh.ChannelTypeMesh] = c.raftController.GetMesh()
	}

	// Channel types routed to a dedicated acceptor above validate their own peers; the connect handler
	// must skip exactly those and validate everything else (which the dispatcher routes to the default
	// router control acceptor, including unrecognized types). Set this before accepting connections.
	separatelyValidatedTypes := map[string]struct{}{}
	for chType := range ctrlAcceptors {
		separatelyValidatedTypes[chType] = struct{}{}
	}
	c.ctrlConnectHandler.SetSeparatelyValidatedChannelTypes(separatelyValidatedTypes)

	if err := c.ctrlListener.Listen(c.ctrlConnectHandler); err != nil {
		panic(err)
	}

	underlayDispatcher := channel.NewUnderlayDispatcher(channel.UnderlayDispatcherConfig{
		Listener:        ctrlListener,
		ConnectTimeout:  c.config.Ctrl.Options.ConnectTimeout,
		Acceptors:       ctrlAcceptors,
		DefaultAcceptor: ctrlAccepter.NewMultiListener(),
	})

	go underlayDispatcher.Run()

	if err = c.config.Configure(c.xweb); err != nil {
		panic(err)
	}

	// Signal that xweb is fully configured. GetApiAddresses waits on this before reading the
	// xweb config, so that mesh hellos triggered by early raft connections can't cache an empty
	// address set (populated only once Configure has run) for the lifetime of the process.
	c.xwebInitialized.MarkInitialized()

	c.xweb.Run()

	for _, helloHeader := range c.GetHelloHeaderProviders() {
		helloHeader.Apply(headers)
	}

	// event handlers
	if err := c.eventDispatcher.WireEventHandlers(c.getEventHandlerConfigs()); err != nil {
		panic(err)
	}

	if c.raftController != nil {
		c.raftController.StartEventGeneration()
	}

	if c.config.Ctrl.Dialer.Enabled {
		ctrlDialer := handler_ctrl.NewCtrlDialer(
			&c.config.Ctrl.Dialer,
			c.network,
			ctrlAccepter,
			c.config.Id,
			headers,
			c.shutdownC,
			c.metricsRegistry,
		)
		c.network.AddRouterPresenceHandler(ctrlDialer)
		c.network.Router.Store.AddEntityIdListener(ctrlDialer.RouterUpdated, boltz.EntityUpdated)
		c.network.Router.Store.AddEntityIdListener(ctrlDialer.RouterCreated, boltz.EntityCreated)
		c.network.Router.Store.AddEntityIdListener(ctrlDialer.RouterDeleted, boltz.EntityDeleted)
		c.network.AddInspectTarget(ctrlDialer.Inspect)
		c.network.SetCtrlDialerValidator(ctrlDialer.Validate)
		go ctrlDialer.Run()
	}

	c.network.Run()

	return nil
}

func (c *Controller) getEventHandlerConfigs() []*events.EventHandlerConfig {
	var result []*events.EventHandlerConfig

	if e, ok := c.config.Src["events"]; ok {
		if em, ok := e.(map[interface{}]interface{}); ok {
			for id, v := range em {
				if eventHandlerConfig, ok := v.(map[interface{}]interface{}); ok {
					result = append(result, &events.EventHandlerConfig{
						Id:     id,
						Config: eventHandlerConfig,
					})
				}
			}
		}
	}
	return result
}

func (c *Controller) GetCloseNotifyChannel() <-chan struct{} {
	return c.shutdownC
}

func (c *Controller) Shutdown() {
	if c.isShutdown.CompareAndSwap(false, true) {
		close(c.shutdownC)

		if c.ctrlListener != nil {
			if err := c.ctrlListener.Close(); err != nil {
				pfxlog.Logger().WithError(err).Error("failed to close ctrl channel listener")
			}
		}

		if c.mgmtListener != nil {
			if err := c.mgmtListener.Close(); err != nil {
				pfxlog.Logger().WithError(err).Error("failed to close mgmt channel listener")
			}
		}

		if c.config.Db != nil {
			if err := c.config.Db.Close(); err != nil {
				pfxlog.Logger().WithError(err).Error("failed to close db")
			}
		}

		go c.xweb.Shutdown()

		if c.raftController != nil {
			if err := c.raftController.Shutdown(); err != nil {
				pfxlog.Logger().WithError(err).Error("failed to shutdown raft")
			}
		}

		c.config.Id.StopWatchingFiles()
		if c.config.Edge.Enrollment.SigningCert != nil {
			c.config.Edge.Enrollment.SigningCert.StopWatchingFiles()
		}

		if c.healthChecker != nil {
			c.healthChecker.DeregisterAll()
		}
	}
}

func (c *Controller) showOptions() error {
	if ctrl, err := json.MarshalIndent(c.config.Ctrl.Options, "", "  "); err == nil {
		pfxlog.Logger().Infof("ctrl = %s", string(ctrl))
	} else {
		return err
	}
	return nil
}

func (c *Controller) startProfiling() {
	if c.config.Profile.Memory.Path != "" {
		go profiler.NewMemoryWithShutdown(c.config.Profile.Memory.Path, c.config.Profile.Memory.Interval, c.shutdownC).Run()
	}
	if c.config.Profile.CPU.Path != "" {
		if cpu, err := profiler.NewCPUWithShutdown(c.config.Profile.CPU.Path, c.shutdownC); err == nil {
			go cpu.Run()
		} else {
			logrus.Errorf("unexpected error launching cpu profiling (%v)", err)
		}
	}
}

func (c *Controller) registerXts() {
	xt.GlobalRegistry().RegisterFactory(xt_smartrouting.NewFactory())
	xt.GlobalRegistry().RegisterFactory(xt_random.NewFactory())
	xt.GlobalRegistry().RegisterFactory(xt_weighted.NewFactory())
	xt.GlobalRegistry().RegisterFactory(xt_sticky.NewFactory())
}

func (c *Controller) registerComponents() error {
	c.ctrlConnectHandler = handler_ctrl.NewConnectHandler(c.config.Id, c.network)
	c.eventDispatcher.AddClusterEventHandler(event.ClusterEventHandlerF(c.routerDispatchCallback))
	return nil
}

func (c *Controller) RegisterXctrl(x xctrl.Xctrl) error {
	if err := c.config.Configure(x); err != nil {
		return err
	}
	if x.Enabled() {
		c.xctrls = append(c.xctrls, x)
		if c.config.Trace.Handler != nil {
			for _, decoder := range x.GetTraceDecoders() {
				c.config.Trace.Handler.AddDecoder(decoder)
			}
		}
	}
	return nil
}

func (c *Controller) RegisterXmgmt(x xmgmt.Xmgmt) error {
	if err := c.config.Configure(x); err != nil {
		return err
	}
	pfxlog.Logger().Infof("adding xmgmt %T, enabled? %v", x, x.Enabled())
	if x.Enabled() {
		c.xmgmts.Append(x)
	}
	return nil
}

func (c *Controller) GetXWebInstance() xweb.Instance {
	return c.xweb
}

func (c *Controller) GetNetwork() *network.Network {
	return c.network
}

func (c *Controller) Identity() identity.Identity {
	return c.config.Id
}

func (c *Controller) GetEventDispatcher() event.Dispatcher {
	return c.eventDispatcher
}

func (c *Controller) routerDispatchCallback(evt *event.ClusterEvent) {
	if evt.EventType == event.ClusterLeadershipGained {
		req := &ctrl_pb.UpdateClusterLeader{
			Index: evt.Index,
		}

		for _, r := range c.network.AllConnectedRouters() {
			log := pfxlog.Logger().WithFields(map[string]interface{}{
				"index": evt.Index,
			})

			if err := protobufs.MarshalTyped(req).Send(r.Control.GetDefaultSender()); err != nil {
				pfxlog.Logger().WithError(err).WithField("routerId", r.Id).Error("unable to update cluster leader on router")
			} else {
				log.WithField("routerId", r.Id).WithField("routerName", r.Name).Info("router updated with info on new leader")
			}
		}
	}

	if evt.EventType == event.ClusterMembersChanged {
		var endpoints []string
		var controllers []*ctrl_pb.CtrlDetail
		for _, peer := range evt.Peers {
			endpoints = append(endpoints, peer.Addr)
			controllers = append(controllers, &ctrl_pb.CtrlDetail{
				Id:        peer.Id,
				Endpoints: []*ctrl_pb.CtrlEndpoint{{Address: peer.Addr}},
			})
		}

		updMsg := &ctrl_pb.UpdateCtrlAddresses{
			Addresses:   endpoints,
			IsLeader:    c.raftController.IsLeader(),
			Index:       evt.Index,
			Controllers: controllers,
		}

		log := pfxlog.Logger().WithFields(map[string]interface{}{
			"addresses": endpoints,
			"index":     evt.Index,
		})

		log.Info("syncing updated ctrl addresses to connected routers")

		for _, r := range c.network.AllConnectedRouters() {
			if err := protobufs.MarshalTyped(updMsg).Send(r.Control.GetDefaultSender()); err != nil {
				pfxlog.Logger().WithError(err).WithField("routerId", r.Id).Error("unable to update controller endpoints on router")
			} else {
				log.WithField("routerId", r.Id).WithField("routerName", r.Name).Info("router updated with latest ctrl addresses")
			}
		}
	}
}

func (c *Controller) getMigrationDb() (*string, error) {
	val, found := c.config.Src["db"]
	if !found {
		return nil, nil
	}

	path := fmt.Sprintf("%v", val)
	if _, err := os.Stat(path); err != nil {
		if os.IsNotExist(err) {
			return nil, errors.Wrapf(err, "source db not found at [%v], either remove 'db' config setting or fix path ", path)
		}
		return nil, errors.Wrapf(err, "invalid db path [%v]", path)
	}

	return &path, nil
}

func (c *Controller) ValidateMigrationEnvironment() error {
	_, err := c.getMigrationDb()
	return err
}

func (c *Controller) TryInitializeRaftFromBoltDb() error {
	path, err := c.getMigrationDb()
	if err != nil || path == nil {
		return err
	}
	return c.InitializeRaftFromBoltDb(*path)
}

func (c *Controller) InitializeRaftFromBoltDb(sourceDbPath string) error {
	if c.raftController == nil {
		return errors.New("can't initialize non-raft controller using initialize from db")
	}

	if c.raftController.IsBootstrapped() {
		return errors.New("raft is already bootstrapped, must start with a uninitialized controller")
	}

	return c.RaftRestoreFromBoltDb(sourceDbPath)
}

// validateMigrationSourceDb rejects a migration source that is not an initialized controller db.
// db.Open creates the root bucket on any file, so existence is not enough; it checks for a default
// admin identity, which an initialized controller always has. The check is read-only.
func validateMigrationSourceDb(sourceDb boltz.Db) error {
	hasDefaultAdmin := false
	err := sourceDb.View(func(tx *bbolt.Tx) error {
		identities := boltz.Path(tx, db.RootBucket, db.EntityTypeIdentities)
		if identities == nil {
			return nil
		}
		return identities.ForEachTypedBucket(func(_ string, identity *boltz.TypedBucket) error {
			if identity.GetBoolWithDefault(db.FieldIdentityIsDefaultAdmin, false) {
				hasDefaultAdmin = true
			}
			return nil
		})
	})
	if err != nil {
		return errors.Wrap(err, "unable to read identities from source db")
	}
	if !hasDefaultAdmin {
		return errors.New("source db has no default admin identity; it is empty or was never a fully initialized controller")
	}
	return nil
}

func (c *Controller) RaftRestoreFromBoltDb(sourceDbPath string) error {
	log := pfxlog.Logger()

	if c.raftController == nil {
		return errors.New("can't initialize non-raft controller using initialize from db")
	}

	if _, err := os.Stat(sourceDbPath); err != nil {
		if os.IsNotExist(err) {
			return errors.Wrapf(err, "source db not found at [%v]", sourceDbPath)
		}
		return errors.Wrapf(err, "invalid db path [%v]", sourceDbPath)
	}

	sourceDb, err := db.Open(sourceDbPath)
	if err != nil {
		return err
	}
	defer func() {
		if err = sourceDb.Close(); err != nil {
			log.WithError(err).Error("error closing migration source bolt db")
		}
	}()

	if err = validateMigrationSourceDb(sourceDb); err != nil {
		return errors.Wrapf(err, "migration source db [%v] is not a valid initialized controller database", sourceDbPath)
	}

	timelineId, err := sourceDb.GetTimelineId(boltz.TimelineModeForceReset, shortid.Generate)
	if err != nil {
		return err
	}
	log.WithField("timelineId", timelineId).WithField("path", sourceDbPath).Info("restoring from bolt db")

	buf := &bytes.Buffer{}
	gzWriter := gzip.NewWriter(buf)
	if err = sourceDb.StreamToWriter(gzWriter); err != nil {
		if closeErr := gzWriter.Close(); closeErr != nil {
			log.WithError(closeErr).Error("error closing db snapshot buffer")
		}
		return err
	}

	if err = gzWriter.Close(); err != nil {
		return errors.Wrap(err, "error finishing gz compression of migration snapshot")
	}

	cmd := &command.SyncSnapshotCommand{
		TimelineId:   timelineId,
		Snapshot:     buf.Bytes(),
		SnapshotSink: c.network.RestoreSnapshot,
	}

	if err = c.raftController.Bootstrap(); err != nil {
		return fmt.Errorf("unable to bootstrap cluster (%w)", err)
	}

	// Carry the cluster id Bootstrap established so RestoreSnapshot can write it back after the
	// restore (the migration source has none). Blank here means a bug in Bootstrap, so fail.
	cmd.ClusterId = c.raftController.GetClusterId()
	if cmd.ClusterId == "" {
		return errors.New("cluster id is blank after bootstrap; refusing to restore without a durable cluster id")
	}

	return c.raftController.Dispatch(cmd)
}

// TODO: this functions is a temporary hack and should be provided by xweb
func getApiPath(binding string) string {
	switch binding {
	case "edge-client":
		return "/edge/client/v1"
	case "edge-management":
		return "/edge/management/v1"
	case "fabric":
		return "/fabric/v1"
	case "health-checks":
		return "/health-checks"
	case "edge-oidc":
		return "/oidc"
	}

	return ""
}

func (c *Controller) GetApiAddresses() (map[string][]event.ApiAddress, []byte) {
	c.apiDataOnce.Do(func() {
		c.xwebInitialized.WaitTillInitialized()
		xwebConfig := c.xweb.GetConfig()

		apiData := map[string][]event.ApiAddress{}
		for _, serverConfig := range xwebConfig.ServerConfigs {
			for _, bindPoint := range serverConfig.BindPoints {
				if bindPoint.Type() != bindpoints.BindPointTypeUnderlay {
					continue
				}
				for _, api := range serverConfig.APIs {
					apiData[api.Binding()] = append(apiData[api.Binding()], event.ApiAddress{
						Url:     "https://" + bindPoint.ServerAddress() + getApiPath(api.Binding()), //TODO: temp till xweb support reporting API paths
						Version: "v1",                                                               //TODO: temp till xweb supports reporting versions via api.Version()
					})
				}
			}
		}

		c.apiData = apiData
		c.apiDataBytes, _ = json.Marshal(apiData)
	})

	return c.apiData, c.apiDataBytes
}

func (c *Controller) GetHelloHeaderProviders() []mesh.HeaderProvider {
	apiAddrProvider := mesh.HeaderProviderFunc(func(headers map[int32][]byte) {
		_, apiDataBytes := c.GetApiAddresses()
		headers[mesh.ApiAddressesHeader] = apiDataBytes
		headers[mesh.LegacyApiAddressesHeader] = apiDataBytes
	})

	preferredLeaderProvider := mesh.HeaderProviderFunc(func(headers map[int32][]byte) {
		if c.config.Raft != nil && c.config.Raft.PreferredLeader {
			headers[mesh.PreferredLeaderHeader] = []byte{1}
		}
	})

	return []mesh.HeaderProvider{apiAddrProvider, preferredLeaderProvider}
}