package edgedb

import (
	"context"
	"fmt"
	"time"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	bannerApi "edge-infra.dev/pkg/edge/apis/banner/v1alpha1"
	clusterApi "edge-infra.dev/pkg/edge/apis/cluster/v1alpha1"
	gkeclusterApi "edge-infra.dev/pkg/edge/apis/gkecluster/v1alpha1"
	"edge-infra.dev/pkg/edge/controllers/dbmetrics"
	"edge-infra.dev/pkg/k8s/meta/status"
	"edge-infra.dev/pkg/k8s/runtime/conditions"
	"edge-infra.dev/pkg/lib/fog"
)

// InfraStatus is an enum whose values are written to the `infra_status` column in the `clusters` & `banners` tables.
type InfraStatus string

const (
	InfraStatusReady InfraStatus = "READY"
	InfraStatusError InfraStatus = "ERROR"

	// Provisioning is the default value when rows are created. The db status util does not set this value.
	InfraStatusProvisioning InfraStatus = "PROVISIONING"
)

const errorLogMessage = "Infra status not recorded"

const sqlUpdateClusterStatus = "UPDATE clusters SET infra_status=$1, infra_status_details=$2, infra_status_updated_at=$3 WHERE cluster_edge_id=$4"
const sqlUpdateBannerStatus = "UPDATE banners SET infra_status=$1, infra_status_details=$2, infra_status_updated_at=$3 WHERE banner_edge_id=$4"

// Record takes a Banner, Cluster, or GKECluster object as input, and writes its infra status to the database. Errors are logged using the passed in context.
//
// NOTE: To make integration testing easier for consumers, this function safely returns, without panicing, when the wrapped DB is nil.
func (edb *EdgeDB) RecordInfraStatus(ctx context.Context, obj conditions.Getter, recorder dbmetrics.DBMetrics) {
	var log = fog.FromContext(ctx).WithName("dbinfrastatus")

	if edb.DB == nil {
		// Quietly exit when the wrapped DB is nil.
		return
	}

	// choose the sql statement based on the object's kind
	var stmt string
	kind := obj.GetObjectKind().GroupVersionKind().Kind
	switch kind {
	case clusterApi.Kind, gkeclusterApi.Kind:
		stmt = sqlUpdateClusterStatus
	case bannerApi.BannerKind:
		stmt = sqlUpdateBannerStatus
	default:
		err := fmt.Errorf("Kind not supported")
		log.Error(err, errorLogMessage, "kind", kind)
		return
	}

	var cv = columnValuesForObject(obj)
	_, err := edb.DB.ExecContext(ctx, stmt, cv.InfraStatus, cv.InfraStatusDetails, cv.InfraStatusUpdatedAt, cv.EdgeID)
	if err != nil {
		log.Error(err, errorLogMessage)
		recorder.RecordDBErrorsTotal(ctx, kind, obj.GetName())
	} else {
		recorder.RecordDBStatusWritesTotal(ctx, kind, toString(cv.InfraStatus))
	}
}

type columnValues struct {
	EdgeID               string
	InfraStatus          InfraStatus
	InfraStatusDetails   string
	InfraStatusUpdatedAt time.Time
}

func conditionStatusToInfraStatus(v metav1.ConditionStatus) InfraStatus {
	if v == metav1.ConditionTrue {
		return InfraStatusReady
	} else if v == metav1.ConditionFalse {
		return InfraStatusError
	}
	return InfraStatusProvisioning
}

func columnValuesForObject(obj conditions.Getter) columnValues {
	for _, cs := range obj.GetConditions() {
		if cs.Type == status.ReadyCondition {
			return columnValues{
				EdgeID:               obj.GetName(),
				InfraStatus:          conditionStatusToInfraStatus(cs.Status),
				InfraStatusDetails:   fmt.Sprintf("%s: %s", cs.Reason, cs.Message),
				InfraStatusUpdatedAt: cs.LastTransitionTime.Time,
			}
		}
	}
	return columnValues{
		EdgeID:               obj.GetName(),
		InfraStatus:          InfraStatusProvisioning,
		InfraStatusDetails:   "Ready condition not found",
		InfraStatusUpdatedAt: time.Now(),
	}
}

func toString(infraStatus InfraStatus) string {
	switch infraStatus {
	case InfraStatusReady:
		return "Ready"
	case InfraStatusError:
		return "Error"
	case InfraStatusProvisioning:
		return "Provisioning"
	default:
		return "Unknown"
	}
}