/*
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 podresources

import (
	"context"

	"k8s.io/kubernetes/pkg/kubelet/metrics"

	"k8s.io/kubelet/pkg/apis/podresources/v1"
	"k8s.io/kubelet/pkg/apis/podresources/v1alpha1"
)

// v1alpha1PodResourcesServer implements PodResourcesListerServer
type v1alpha1PodResourcesServer struct {
	podsProvider    PodsProvider
	devicesProvider DevicesProvider
}

// NewV1alpha1PodResourcesServer returns a PodResourcesListerServer which lists pods provided by the PodsProvider
// with device information provided by the DevicesProvider
func NewV1alpha1PodResourcesServer(providers PodResourcesProviders) v1alpha1.PodResourcesListerServer {
	return &v1alpha1PodResourcesServer{
		podsProvider:    providers.Pods,
		devicesProvider: providers.Devices,
	}
}

func v1DevicesToAlphaV1(alphaDevs []*v1.ContainerDevices) []*v1alpha1.ContainerDevices {
	var devs []*v1alpha1.ContainerDevices
	for _, alphaDev := range alphaDevs {
		dev := v1alpha1.ContainerDevices{
			ResourceName: alphaDev.ResourceName,
			DeviceIds:    alphaDev.DeviceIds,
		}
		devs = append(devs, &dev)
	}

	return devs
}

// List returns information about the resources assigned to pods on the node
func (p *v1alpha1PodResourcesServer) List(ctx context.Context, req *v1alpha1.ListPodResourcesRequest) (*v1alpha1.ListPodResourcesResponse, error) {
	metrics.PodResourcesEndpointRequestsTotalCount.WithLabelValues("v1alpha1").Inc()
	pods := p.podsProvider.GetPods()
	podResources := make([]*v1alpha1.PodResources, len(pods))
	p.devicesProvider.UpdateAllocatedDevices()

	for i, pod := range pods {
		pRes := v1alpha1.PodResources{
			Name:       pod.Name,
			Namespace:  pod.Namespace,
			Containers: make([]*v1alpha1.ContainerResources, len(pod.Spec.Containers)),
		}

		for j, container := range pod.Spec.Containers {
			pRes.Containers[j] = &v1alpha1.ContainerResources{
				Name:    container.Name,
				Devices: v1DevicesToAlphaV1(p.devicesProvider.GetDevices(string(pod.UID), container.Name)),
			}
		}
		podResources[i] = &pRes
	}

	return &v1alpha1.ListPodResourcesResponse{
		PodResources: podResources,
	}, nil
}