/*
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 test

import (
	apiv1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/api/resource"

	vpa_types "k8s.io/autoscaler/vertical-pod-autoscaler/pkg/apis/autoscaling.k8s.io/v1"
)

// RecommendationBuilder helps building test instances of RecommendedPodResources.
type RecommendationBuilder interface {
	WithContainer(containerName string) RecommendationBuilder
	WithTarget(cpu, memory string) RecommendationBuilder
	WithTargetResource(resource apiv1.ResourceName, value string) RecommendationBuilder
	WithLowerBound(cpu, memory string) RecommendationBuilder
	WithUpperBound(cpu, memory string) RecommendationBuilder
	Get() *vpa_types.RecommendedPodResources
	GetContainerResources() vpa_types.RecommendedContainerResources
}

// TODO part of this interface is repeated in VerticalPodAutoscalerBuilder, we can probably factorize some code

// Recommendation returns a new RecommendationBuilder.
func Recommendation() RecommendationBuilder {
	return &recommendationBuilder{}
}

type recommendationBuilder struct {
	containerName string
	target        apiv1.ResourceList
	lowerBound    apiv1.ResourceList
	upperBound    apiv1.ResourceList
}

func (b *recommendationBuilder) WithContainer(containerName string) RecommendationBuilder {
	c := *b
	c.containerName = containerName
	return &c
}

func (b *recommendationBuilder) WithTarget(cpu, memory string) RecommendationBuilder {
	c := *b
	c.target = Resources(cpu, memory)
	return &c
}

func (b *recommendationBuilder) WithTargetResource(resource apiv1.ResourceName, value string) RecommendationBuilder {
	c := *b
	if c.target == nil {
		c.target = apiv1.ResourceList{}
	}
	addResource(c.target, resource, value)
	return &c
}

func (b *recommendationBuilder) WithLowerBound(cpu, memory string) RecommendationBuilder {
	c := *b
	c.lowerBound = Resources(cpu, memory)
	return &c
}

func (b *recommendationBuilder) WithUpperBound(cpu, memory string) RecommendationBuilder {
	c := *b
	c.upperBound = Resources(cpu, memory)
	return &c
}

func (b *recommendationBuilder) Get() *vpa_types.RecommendedPodResources {
	if b.containerName == "" {
		panic("Must call WithContainer() before Get()")
	}
	return &vpa_types.RecommendedPodResources{
		ContainerRecommendations: []vpa_types.RecommendedContainerResources{
			{
				ContainerName:  b.containerName,
				Target:         b.target,
				UncappedTarget: b.target,
				LowerBound:     b.lowerBound,
				UpperBound:     b.upperBound,
			},
		}}
}

func (b *recommendationBuilder) GetContainerResources() vpa_types.RecommendedContainerResources {
	return vpa_types.RecommendedContainerResources{
		ContainerName:  b.containerName,
		Target:         b.target,
		UncappedTarget: b.target,
		LowerBound:     b.lowerBound,
		UpperBound:     b.upperBound,
	}
}

// addResource add a resource to the given resource list
func addResource(rl apiv1.ResourceList, resourceName apiv1.ResourceName, value string) apiv1.ResourceList {
	val, _ := resource.ParseQuantity(value)
	if rl == nil {
		rl = apiv1.ResourceList{}
	}
	rl[resourceName] = val
	return rl
}