/*
Copyright 2018 The Kubernetes Authors.

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 status

import (
	"time"

	"k8s.io/autoscaler/cluster-autoscaler/clusterstate"
	"k8s.io/autoscaler/cluster-autoscaler/context"
	"k8s.io/autoscaler/cluster-autoscaler/metrics"
	"k8s.io/autoscaler/cluster-autoscaler/utils/backoff"
)

const (
	// unknownErrorCode means that the cloud provider has not provided an error code.
	unknownErrorCode = "unknown"
)

// BackoffReasonStatus contains information about backoff status and reason
type BackoffReasonStatus map[string]bool

// MetricsAutoscalingStatusProcessor is used to update metrics after each autoscaling iteration.
type MetricsAutoscalingStatusProcessor struct {
	backoffReasonStatus map[string]BackoffReasonStatus
}

// Process queries the health status and backoff situation of all node groups and updates metrics after each autoscaling iteration.
func (p *MetricsAutoscalingStatusProcessor) Process(context *context.AutoscalingContext, csr *clusterstate.ClusterStateRegistry, now time.Time) error {
	for _, nodeGroup := range context.CloudProvider.NodeGroups() {
		if !nodeGroup.Exist() {
			continue
		}
		metrics.UpdateNodeGroupHealthStatus(nodeGroup.Id(), csr.IsNodeGroupHealthy(nodeGroup.Id()))
		backoffStatus := csr.BackoffStatusForNodeGroup(nodeGroup, now)
		p.updateNodeGroupBackoffStatusMetrics(nodeGroup.Id(), backoffStatus)
	}
	return nil
}

// CleanUp cleans up the processor's internal structures.
func (p *MetricsAutoscalingStatusProcessor) CleanUp() {
}

// updateNodeGroupBackoffStatusMetrics updates metrics about backoff situation and reason of the node group
func (p *MetricsAutoscalingStatusProcessor) updateNodeGroupBackoffStatusMetrics(nodeGroup string, backoffStatus backoff.Status) {
	if _, ok := p.backoffReasonStatus[nodeGroup]; ok {
		for reason := range p.backoffReasonStatus[nodeGroup] {
			p.backoffReasonStatus[nodeGroup][reason] = false
		}
	} else {
		p.backoffReasonStatus[nodeGroup] = make(BackoffReasonStatus)
	}

	if backoffStatus.IsBackedOff {
		errorCode := backoffStatus.ErrorInfo.ErrorCode
		if errorCode == "" {
			// prevent error code from being empty.
			errorCode = unknownErrorCode
		}
		p.backoffReasonStatus[nodeGroup][errorCode] = true
	}
	metrics.UpdateNodeGroupBackOffStatus(nodeGroup, p.backoffReasonStatus[nodeGroup])
}