// Copyright 2019 Yunion
//
// 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
//
//     http://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 models

import (
	"context"
	"reflect"

	"yunion.io/x/jsonutils"
	"yunion.io/x/log"
	"yunion.io/x/pkg/errors"
	"yunion.io/x/pkg/gotypes"
	"yunion.io/x/pkg/util/seclib"
	"yunion.io/x/sqlchemy"

	"yunion.io/x/onecloud/pkg/apis"
	api "yunion.io/x/onecloud/pkg/apis/compute"
	"yunion.io/x/onecloud/pkg/cloudcommon/db"
	"yunion.io/x/onecloud/pkg/cloudcommon/validators"
	"yunion.io/x/onecloud/pkg/httperrors"
	"yunion.io/x/onecloud/pkg/mcclient"
	"yunion.io/x/onecloud/pkg/util/logclient"
	"yunion.io/x/onecloud/pkg/util/stringutils2"
)

// +onecloud:swagger-gen-model-singular=loadbalancercluster
// +onecloud:swagger-gen-model-plural=loadbalancerclusters
type SLoadbalancerClusterManager struct {
	db.SStandaloneResourceBaseManager
	SZoneResourceBaseManager
	SWireResourceBaseManager
}

var LoadbalancerClusterManager *SLoadbalancerClusterManager

func init() {
	gotypes.RegisterSerializable(reflect.TypeOf(&SLoadbalancerClusterParams{}), func() gotypes.ISerializable {
		return &SLoadbalancerClusterParams{}
	})
	LoadbalancerClusterManager = &SLoadbalancerClusterManager{
		SStandaloneResourceBaseManager: db.NewStandaloneResourceBaseManager(
			SLoadbalancerCluster{},
			"loadbalancerclusters_tbl",
			"loadbalancercluster",
			"loadbalancerclusters",
		),
	}
	LoadbalancerClusterManager.SetVirtualObject(LoadbalancerClusterManager)
}

type SLoadbalancerCluster struct {
	db.SStandaloneResourceBase
	SZoneResourceBase
	SWireResourceBase `width:"36" charset:"ascii" nullable:"true" list:"admin" create:"optional" update:"admin"`

	Params *SLoadbalancerClusterParams `nullable:"true" create:"optional" list:"admin" get:"admin"`
}

// 负载均衡集群列表
func (man *SLoadbalancerClusterManager) ListItemFilter(
	ctx context.Context,
	q *sqlchemy.SQuery,
	userCred mcclient.TokenCredential,
	query api.LoadbalancerClusterListInput,
) (*sqlchemy.SQuery, error) {
	var err error

	q, err = man.SStandaloneResourceBaseManager.ListItemFilter(ctx, q, userCred, query.StandaloneResourceListInput)
	if err != nil {
		return nil, errors.Wrap(err, "SStandaloneResourceBaseManager.ListItemFilter")
	}
	q, err = man.SZoneResourceBaseManager.ListItemFilter(ctx, q, userCred, query.ZonalFilterListInput)
	if err != nil {
		return nil, errors.Wrap(err, "SZoneResourceBaseManager.ListItemFilter")
	}
	wireQuery := api.WireFilterListInput{
		WireFilterListBase: query.WireFilterListBase,
	}
	q, err = man.SWireResourceBaseManager.ListItemFilter(ctx, q, userCred, wireQuery)
	if err != nil {
		return nil, errors.Wrap(err, "SWireResourceBaseManager.ListItemFilter")
	}

	return q, nil
}

func (man *SLoadbalancerClusterManager) OrderByExtraFields(
	ctx context.Context,
	q *sqlchemy.SQuery,
	userCred mcclient.TokenCredential,
	query api.LoadbalancerClusterListInput,
) (*sqlchemy.SQuery, error) {
	var err error

	q, err = man.SStandaloneResourceBaseManager.OrderByExtraFields(ctx, q, userCred, query.StandaloneResourceListInput)
	if err != nil {
		return nil, errors.Wrap(err, "SStandaloneResourceBaseManager.OrderByExtraFields")
	}
	q, err = man.SZoneResourceBaseManager.OrderByExtraFields(ctx, q, userCred, query.ZonalFilterListInput)
	if err != nil {
		return nil, errors.Wrap(err, "SZoneResourceBaseManager.OrderByExtraFields")
	}
	wireQuery := api.WireFilterListInput{
		WireFilterListBase: query.WireFilterListBase,
	}
	q, err = man.SWireResourceBaseManager.OrderByExtraFields(ctx, q, userCred, wireQuery)
	if err != nil {
		return nil, errors.Wrap(err, "SWireResourceBaseManager.OrderByExtraFields")
	}

	return q, nil
}

func (man *SLoadbalancerClusterManager) QueryDistinctExtraField(q *sqlchemy.SQuery, field string) (*sqlchemy.SQuery, error) {
	var err error

	q, err = man.SStandaloneResourceBaseManager.QueryDistinctExtraField(q, field)
	if err == nil {
		return q, nil
	}
	q, err = man.SZoneResourceBaseManager.QueryDistinctExtraField(q, field)
	if err == nil {
		return q, nil
	}
	q, err = man.SWireResourceBaseManager.QueryDistinctExtraField(q, field)
	if err == nil {
		return q, nil
	}

	return q, httperrors.ErrNotFound
}

func (man *SLoadbalancerClusterManager) ValidateCreateData(
	ctx context.Context,
	userCred mcclient.TokenCredential,
	ownerId mcclient.IIdentityProvider,
	query jsonutils.JSONObject,
	data *jsonutils.JSONDict,
) (*jsonutils.JSONDict, error) {
	zoneV := validators.NewModelIdOrNameValidator("zone", "zone", ownerId)
	wireV := validators.NewModelIdOrNameValidator("wire", "wire", ownerId)
	vs := []validators.IValidator{
		zoneV,
		wireV.Optional(true),
	}
	for _, v := range vs {
		if err := v.Validate(ctx, data); err != nil {
			return nil, err
		}
	}
	zone := zoneV.Model.(*SZone)
	if zone.ExternalId != "" {
		return nil, httperrors.NewInputParameterError("allow only internal zone, got %s(%s)", zone.Name, zone.Id)
	}
	if wireV.Model != nil {
		wire := wireV.Model.(*SWire)
		if wire.ZoneId != zone.Id {
			return nil, httperrors.NewInputParameterError("wire zone must match zone parameter, got %s, want %s(%s)",
				wire.ZoneId, zone.Name, zone.Id)
		}
	}

	input := apis.StandaloneResourceCreateInput{}
	err := data.Unmarshal(&input)
	if err != nil {
		return nil, httperrors.NewInternalServerError("unmarshal StandaloneResourceCreateInput fail %s", err)
	}
	input, err = man.SStandaloneResourceBaseManager.ValidateCreateData(ctx, userCred, ownerId, query, input)
	if err != nil {
		return nil, err
	}
	data.Update(jsonutils.Marshal(input))
	return data, nil
}

func (cluster *SLoadbalancerCluster) PostCreate(
	ctx context.Context,
	userCred mcclient.TokenCredential,
	ownerId mcclient.IIdentityProvider,
	query jsonutils.JSONObject,
	data jsonutils.JSONObject,
) {
	err := cluster.selfInitParams()
	if err != nil {
		log.Errorf("fail to generate cluster params: %s", err)
		logclient.AddSimpleActionLog(cluster, logclient.ACT_CREATE, err, userCred, false)
	} else {
		logclient.AddSimpleActionLog(cluster, logclient.ACT_CREATE, cluster.Params, userCred, true)
	}
}

func (lbc *SLoadbalancerCluster) ValidateUpdateData(
	ctx context.Context,
	userCred mcclient.TokenCredential,
	query jsonutils.JSONObject,
	data *jsonutils.JSONDict,
) (*jsonutils.JSONDict, error) {
	wireV := validators.NewModelIdOrNameValidator("wire", "wire", lbc.GetOwnerId())
	wireV.Optional(true)
	if err := wireV.Validate(ctx, data); err != nil {
		return nil, err
	}
	if wireV.Model != nil {
		wire := wireV.Model.(*SWire)
		if wire.ZoneId != lbc.ZoneId {
			return nil, httperrors.NewInputParameterError("zone of wire must be %s, got %s", lbc.ZoneId, wire.ZoneId)
		}
		var from string
		if lbc.WireId != "" {
			from = "from " + lbc.WireId + " "
		}
		log.Infof("changing wire attribute of lbcluster %s(%s) %sto %s(%s)",
			lbc.Name, lbc.Id, from, wire.Name, wire.Id)
	}

	input := apis.StandaloneResourceBaseUpdateInput{}
	err := data.Unmarshal(&input)
	if err != nil {
		return nil, errors.Wrap(err, "Unmarshal")
	}
	input, err = lbc.SStandaloneResourceBase.ValidateUpdateData(ctx, userCred, query, input)
	if err != nil {
		return nil, errors.Wrap(err, "SStandaloneResourceBase.ValidateUpdateData")
	}
	data.Update(jsonutils.Marshal(input))

	return data, nil
}

func (lbc *SLoadbalancerCluster) ValidateDeleteCondition(ctx context.Context, info jsonutils.JSONObject) error {
	refCnts, err := lbc.refCounts()
	if err != nil {
		return errors.Wrap(err, "refCounts")
	}
	errs := make([]error, 0)
	for k, cnt := range refCnts {
		errs = append(errs, httperrors.NewResourceBusyError("lbcluster %s(%s) is still referred to by %d %s",
			lbc.Id, lbc.Name, cnt, k))
	}
	if len(errs) > 0 {
		return errors.NewAggregate(errs)
	}
	return lbc.SStandaloneResourceBase.ValidateDeleteCondition(ctx, nil)
}

func (lbc *SLoadbalancerCluster) refCounts() (map[string]int, error) {
	ret := make(map[string]int)
	men := []db.IModelManager{
		LoadbalancerManager,
		LoadbalancerAgentManager,
	}
	for _, man := range men {
		q := man.Query().Equals("cluster_id", lbc.Id)
		n, err := q.CountWithError()
		if err != nil {
			return nil, httperrors.NewInternalServerError("get lbcluster refcount fail %v", err)
		}
		if n > 0 {
			ret[man.KeywordPlural()] = n
		}
	}
	return ret, nil
}

func (man *SLoadbalancerClusterManager) FetchCustomizeColumns(
	ctx context.Context,
	userCred mcclient.TokenCredential,
	query jsonutils.JSONObject,
	objs []interface{},
	fields stringutils2.SSortedStrings,
	isList bool,
) []api.LoadbalancerClusterDetails {
	rows := make([]api.LoadbalancerClusterDetails, len(objs))

	stdRows := man.SStandaloneResourceBaseManager.FetchCustomizeColumns(ctx, userCred, query, objs, fields, isList)
	zoneRows := man.SZoneResourceBaseManager.FetchCustomizeColumns(ctx, userCred, query, objs, fields, isList)
	wireRows := man.SWireResourceBaseManager.FetchCustomizeColumns(ctx, userCred, query, objs, fields, isList)

	for i := range rows {
		rows[i] = api.LoadbalancerClusterDetails{
			StandaloneResourceDetails: stdRows[i],
			ZoneResourceInfo:          zoneRows[i],
			WireResourceInfoBase:      wireRows[i].WireResourceInfoBase,
		}
		lbc := objs[i].(*SLoadbalancerCluster)
		rows[i].RefCounts, _ = lbc.refCounts()
	}

	return rows
}

func (lbc *SLoadbalancerCluster) CustomizeDelete(ctx context.Context, userCred mcclient.TokenCredential, query jsonutils.JSONObject, data jsonutils.JSONObject) error {
	lbagents := []SLoadbalancerAgent{}
	q := LoadbalancerAgentManager.Query().Equals("cluster_id", lbc.Id)
	if err := db.FetchModelObjects(LoadbalancerAgentManager, q, &lbagents); err != nil {
		return errors.Wrapf(err, "lbcluster %s(%s): find lbagents", lbc.Name, lbc.Id)
	}
	for i := range lbagents {
		lbagent := &lbagents[i]
		if err := lbagent.ValidateDeleteCondition(ctx, nil); err != nil {
			return errors.Wrapf(err, "lbagent %s(%s): validate delete", lbagent.Name, lbagent.Id)
		}
		if err := lbagent.CustomizeDelete(ctx, userCred, query, data); err != nil {
			return errors.Wrapf(err, "lbagent %s(%s): customize delete", lbagent.Name, lbagent.Id)
		}
		lbagent.PreDelete(ctx, userCred)
		if err := lbagent.Delete(ctx, userCred); err != nil {
			return errors.Wrapf(err, "lbagent %s(%s): delete", lbagent.Name, lbagent.Id)
		}
		lbagent.PostDelete(ctx, userCred)
	}
	return lbc.SStandaloneResourceBase.CustomizeDelete(ctx, userCred, query, data)
}

func (man *SLoadbalancerClusterManager) FindByZoneId(zoneId string) []SLoadbalancerCluster {
	r := []SLoadbalancerCluster{}
	q := man.Query().Equals("zone_id", zoneId)
	if err := db.FetchModelObjects(man, q, &r); err != nil {
		log.Errorf("find lbclusters by zone_id %s: %v", zoneId, err)
		return nil
	}
	return r
}

func (man *SLoadbalancerClusterManager) findByVrrpRouterIdInZone(zoneId string, routerId int) ([]*SLoadbalancerCluster, error) {
	r := make([]*SLoadbalancerCluster, 0)

	peerClusters := man.FindByZoneId(zoneId)
	for i := range peerClusters {
		peerCluster := &peerClusters[i]
		if peerCluster.Params.VirtualRouterId == routerId {
			r = append(r, peerCluster)
		}
	}
	return r, nil
}

func (man *SLoadbalancerClusterManager) getVrrpRouterIdsInZone(zoneId string) ([]int, error) {
	q := man.Query().IsNotEmpty("params").Equals("zone_id", zoneId)
	clusters := make([]SLoadbalancerCluster, 0)
	err := db.FetchModelObjects(man, q, &clusters)
	if err != nil {
		return nil, errors.Wrap(err, "initParams.FetchModelObjects")
	}
	ret := make([]int, 0)
	for i := range clusters {
		if clusters[i].Params.VirtualRouterId > 0 {
			ret = append(ret, clusters[i].Params.VirtualRouterId)
		}
	}
	return ret, nil
}

func isInArray[K comparable](v K, arr []K) bool {
	for i := range arr {
		if arr[i] == v {
			return true
		}
	}
	return false
}

func (man *SLoadbalancerClusterManager) newVrrpRouterIdsInZone(zoneId string) (int, error) {
	idList, err := man.getVrrpRouterIdsInZone(zoneId)
	if err != nil {
		return -1, errors.Wrap(err, "getVrrpRouterIdsInZone")
	}
	for i := 17; i < 250; i++ {
		if !isInArray(i, idList) {
			return i, nil
		}
	}
	return -1, errors.Wrapf(httperrors.ErrNotFound, "no available vrrp router id in zone %s", zoneId)
}

func (man *SLoadbalancerClusterManager) getLoadbalancerAgents(clusterId string) ([]SLoadbalancerAgent, error) {
	r := []SLoadbalancerAgent{}
	q := LoadbalancerAgentManager.Query().Equals("cluster_id", clusterId)
	err := db.FetchModelObjects(LoadbalancerAgentManager, q, &r)
	if err != nil {
		return nil, err
	}
	return r, nil
}

func (man *SLoadbalancerClusterManager) InitializeData() error {
	// find existing lb with empty clusterid
	lbs := []SLoadbalancer{}
	lbQ := LoadbalancerManager.Query()
	vpcs := VpcManager.Query().SubQuery()
	lbQ = lbQ.Join(vpcs, sqlchemy.Equals(lbQ.Field("vpc_id"), vpcs.Field("id")))
	lbQ = lbQ.Filter(sqlchemy.IsFalse(lbQ.Field("pending_deleted")))
	lbQ = lbQ.Filter(sqlchemy.IsNullOrEmpty(vpcs.Field("manager_id")))
	lbQ = lbQ.Filter(sqlchemy.IsNullOrEmpty(lbQ.Field("cluster_id")))
	if err := db.FetchModelObjects(LoadbalancerManager, lbQ, &lbs); err != nil {
		return errors.Wrap(err, "find lb with empty cluster_id")
	}

	// create 1 cluster for each zone
	zoneCluster := map[string]*SLoadbalancerCluster{}
	for i := range lbs {
		lb := &lbs[i]
		zoneId := lb.ZoneId
		if zoneId == "" {
			// just in case
			log.Warningf("found lb with empty zone_id: %s(%s)", lb.Name, lb.Id)
			continue
		}
		lbc, ok := zoneCluster[zoneId]
		if !ok {
			lbcs := man.FindByZoneId(zoneId)
			if len(lbcs) == 0 {
				m, err := db.NewModelObject(man)
				if err != nil {
					return errors.Wrap(err, "new model object")
				}
				lbc = m.(*SLoadbalancerCluster)
				lbc.Name = "auto-lbc-" + zoneId
				lbc.ZoneId = zoneId
				if err := man.TableSpec().Insert(context.TODO(), lbc); err != nil {
					return errors.Wrap(err, "insert lbcluster model")
				}
			} else {
				if len(lbcs) > 1 {
					log.Infof("zone %s has %d lbclusters, select one", zoneId, len(lbcs))
				}
				lbc = &lbcs[0]
			}
			zoneCluster[zoneId] = lbc
		}
		if _, err := db.UpdateWithLock(context.Background(), lb, func() error {
			lb.ClusterId = lbc.Id
			return nil
		}); err != nil {
			return errors.Wrapf(err, "lb %s(%s): assign cluster: %s(%s)", lb.Name, lb.Name, lbc.Name, lbc.Id)
		}
	}

	// associate existing lbagents with the cluster
	if len(zoneCluster) > 1 {
		log.Warningf("found %d zones with lb not assigned to any lbcluster, skip assigning lbagent to lbcluster", len(zoneCluster))
		return nil
	}
	for _, lbc := range zoneCluster {
		lbagents := []SLoadbalancerAgent{}
		q := LoadbalancerAgentManager.Query().
			IsNullOrEmpty("cluster_id")
		if err := db.FetchModelObjects(LoadbalancerAgentManager, q, &lbagents); err != nil {
			return errors.Wrap(err, "find lbagents with empty cluster_id")
		}
		for i := range lbagents {
			lbagent := &lbagents[i]
			if _, err := db.UpdateWithLock(context.Background(), lbagent, func() error {
				lbagent.ClusterId = lbc.Id
				return nil
			}); err != nil {
				return errors.Wrapf(err, "lbagent %s(%s): assign cluster: %s(%s)",
					lbagent.Name, lbagent.Id, lbc.Name, lbc.Id)
			}
		}
	}

	man.initParams()

	return nil
}

func (man *SLoadbalancerClusterManager) initParams() error {
	q := man.Query().IsNullOrEmpty("params")
	clusters := make([]SLoadbalancerCluster, 0)
	err := db.FetchModelObjects(man, q, &clusters)
	if err != nil {
		return errors.Wrap(err, "initParams.FetchModelObjects")
	}
	for i := range clusters {
		err := clusters[i].initParams()
		if err != nil {
			return errors.Wrap(err, "cluster initParams")
		}
	}
	return nil
}

func (cluster *SLoadbalancerCluster) initParams() error {
	lbagents, err := LoadbalancerClusterManager.getLoadbalancerAgents(cluster.Id)
	if err != nil {
		return errors.Wrap(err, "getLoadbalancerAgents")
	}
	if len(lbagents) == 0 {
		// generate params
		return cluster.selfInitParams()
	}
	_, err = db.Update(cluster, func() error {
		cluster.Params = &lbagents[0].Params.Vrrp.SLoadbalancerClusterParams
		return nil
	})
	if err != nil {
		return errors.Wrap(err, "UpdateWithLock")
	}
	return nil
}

func (cluster *SLoadbalancerCluster) selfInitParams() error {
	newRouterId, err := LoadbalancerClusterManager.newVrrpRouterIdsInZone(cluster.ZoneId)
	if err != nil {
		return errors.Wrap(err, "newVrrpRouterIdsInZone")
	}
	params := SLoadbalancerClusterParams{
		VirtualRouterId:   newRouterId,
		Preempt:           false,
		AdvertInt:         5,
		Pass:              seclib.RandomPassword(6),
		GarpMasterRefresh: 29,
	}
	_, err = db.Update(cluster, func() error {
		cluster.Params = &params
		return nil
	})
	if err != nil {
		return errors.Wrap(err, "UpdateWithLock")
	}
	return nil
}

func (manager *SLoadbalancerClusterManager) ListItemExportKeys(ctx context.Context,
	q *sqlchemy.SQuery,
	userCred mcclient.TokenCredential,
	keys stringutils2.SSortedStrings,
) (*sqlchemy.SQuery, error) {
	var err error
	q, err = manager.SStandaloneResourceBaseManager.ListItemExportKeys(ctx, q, userCred, keys)
	if err != nil {
		return nil, errors.Wrap(err, "SStandaloneResourceBaseManager.ListItemExportKeys")
	}
	if keys.ContainsAny(manager.SZoneResourceBaseManager.GetExportKeys()...) {
		q, err = manager.SZoneResourceBaseManager.ListItemExportKeys(ctx, q, userCred, keys)
		if err != nil {
			return nil, errors.Wrap(err, "SZoneResourceBaseManager.ListItemExportKeys")
		}
	}
	if keys.Contains("wire") {
		q, err = manager.SWireResourceBaseManager.ListItemExportKeys(ctx, q, userCred, stringutils2.NewSortedStrings([]string{"wire"}))
		if err != nil {
			return nil, errors.Wrap(err, "SWireResourceBaseManager.ListItemExportKeys")
		}
	}
	return q, nil
}

func (cluster *SLoadbalancerCluster) PerformParamsPatch(ctx context.Context, userCred mcclient.TokenCredential, query jsonutils.JSONObject, data *jsonutils.JSONDict) (*jsonutils.JSONDict, error) {
	oldParams := cluster.Params
	params := gotypes.DeepCopy(*cluster.Params).(SLoadbalancerClusterParams)
	d := jsonutils.NewDict()
	d.Set("params", data)
	paramsV := validators.NewStructValidator("params", &params)
	if err := paramsV.Validate(ctx, d); err != nil {
		return nil, err
	}
	// new vrrp virtual_router_id should be unique across clusters
	if params.VirtualRouterId != oldParams.VirtualRouterId {
		otherClusters, err := LoadbalancerClusterManager.findByVrrpRouterIdInZone(cluster.ZoneId, params.VirtualRouterId)
		if err != nil {
			return nil, errors.Wrap(err, "findByVrrpRouterIdInZone")
		}
		if len(otherClusters) > 0 {
			return nil, httperrors.NewConflictError("lbcluster %s(%s) already has virtual_router_id %d",
				otherClusters[0].Name, otherClusters[0].Id, params.VirtualRouterId)
		}
	}
	{
		// save name, description, params
		input := apis.StandaloneResourceBaseUpdateInput{}
		err := data.Unmarshal(&input)
		if err != nil {
			return nil, errors.Wrap(err, "Unmarshal update input")
		}
		input, err = cluster.SStandaloneResourceBase.ValidateUpdateData(ctx, userCred, query, input)
		if err != nil {
			return nil, errors.Wrap(err, "SStandaloneResourceBase.ValidateUpdateData")
		}

		diff, err := db.Update(cluster, func() error {
			cluster.Params = &params
			if len(input.Name) > 0 {
				cluster.Name = input.Name
			}
			if len(input.Description) > 0 {
				cluster.Description = input.Description
			}
			return nil
		})
		if err != nil {
			return nil, errors.Wrap(err, "Update")
		}
		db.OpsLog.LogEvent(cluster, db.ACT_UPDATE, diff, userCred)
	}
	{
		// save metadata
		cluster.TrySaveMetadataInput(ctx, userCred, data)
	}
	{
		// populate changes to underlying lbagents
		lbagents, err := LoadbalancerAgentManager.getByClusterId(cluster.Id)
		if err != nil {
			return nil, errors.Wrap(err, "getByClusterId")
		}
		for i := range lbagents {
			lbagent := lbagents[i]
			params := *lbagent.Params
			params.Vrrp.SLoadbalancerClusterParams = *cluster.Params
			_, err := db.Update(&lbagent, func() error {
				lbagent.Params = &params
				return nil
			})
			if err != nil {
				return nil, errors.Wrap(err, "Update")
			}
		}
	}
	return nil, nil
}