// GetPodJobs returns a list of jobs managing a pod. Returns an error only if no matching jobs are found.
func (s *StoreToJobLister) GetPodJobs(pod *api.Pod) (jobs []batch.Job, err error) {
	var selector labels.Selector
	var job batch.Job

	if len(pod.Labels) == 0 {
		err = fmt.Errorf("no jobs found for pod %v because it has no labels", pod.Name)
		return
	}

	for _, m := range s.Store.List() {
		job = *m.(*batch.Job)
		if job.Namespace != pod.Namespace {
			continue
		}

		selector, _ = unversioned.LabelSelectorAsSelector(job.Spec.Selector)
		if !selector.Matches(labels.Set(pod.Labels)) {
			continue
		}
		jobs = append(jobs, job)
	}
	if len(jobs) == 0 {
		err = fmt.Errorf("could not find jobs for pod %s in namespace %s with labels: %v", pod.Name, pod.Namespace, pod.Labels)
	}
	return
}

// GetPodPetSets returns a list of PetSets managing a pod. Returns an error only if no matching PetSets are found.
func (s *StoreToPetSetLister) GetPodPetSets(pod *api.Pod) (psList []apps.PetSet, err error) {
	var selector labels.Selector
	var ps apps.PetSet

	if len(pod.Labels) == 0 {
		err = fmt.Errorf("no PetSets found for pod %v because it has no labels", pod.Name)
		return
	}

	for _, m := range s.Store.List() {
		ps = *m.(*apps.PetSet)
		if ps.Namespace != pod.Namespace {
			continue
		}
		selector, err = unversioned.LabelSelectorAsSelector(ps.Spec.Selector)
		if err != nil {
			err = fmt.Errorf("invalid selector: %v", err)
			return
		}

		// If a PetSet with a nil or empty selector creeps in, it should match nothing, not everything.
		if selector.Empty() || !selector.Matches(labels.Set(pod.Labels)) {
			continue
		}
		psList = append(psList, ps)
	}
	if len(psList) == 0 {
		err = fmt.Errorf("could not find PetSet for pod %s in namespace %s with labels: %v", pod.Name, pod.Namespace, pod.Labels)
	}
	return
}

// TODO: Move this back to scheduler as a helper function that takes a Store,
// rather than a method of StoreToServiceLister.
func (s *StoreToServiceLister) GetPodServices(pod *api.Pod) (services []api.Service, err error) {
	var selector labels.Selector
	var service api.Service

	for _, m := range s.Store.List() {
		service = *m.(*api.Service)
		// consider only services that are in the same namespace as the pod
		if service.Namespace != pod.Namespace {
			continue
		}
		if service.Spec.Selector == nil {
			// services with nil selectors match nothing, not everything.
			continue
		}
		selector = labels.Set(service.Spec.Selector).AsSelector()
		if selector.Matches(labels.Set(pod.Labels)) {
			services = append(services, service)
		}
	}
	if len(services) == 0 {
		err = fmt.Errorf("could not find service for pod %s in namespace %s with labels: %v", pod.Name, pod.Namespace, pod.Labels)
	}

	return
}

// GetPodDaemonSets returns a list of daemon sets managing a pod.
// Returns an error if and only if no matching daemon sets are found.
func (s *StoreToDaemonSetLister) GetPodDaemonSets(pod *api.Pod) (daemonSets []extensions.DaemonSet, err error) {
	var selector labels.Selector
	var daemonSet extensions.DaemonSet

	if len(pod.Labels) == 0 {
		err = fmt.Errorf("no daemon sets found for pod %v because it has no labels", pod.Name)
		return
	}

	for _, m := range s.Store.List() {
		daemonSet = *m.(*extensions.DaemonSet)
		if daemonSet.Namespace != pod.Namespace {
			continue
		}
		selector, err = unversioned.LabelSelectorAsSelector(daemonSet.Spec.Selector)
		if err != nil {
			// this should not happen if the DaemonSet passed validation
			return nil, err
		}

		// If a daemonSet with a nil or empty selector creeps in, it should match nothing, not everything.
		if selector.Empty() || !selector.Matches(labels.Set(pod.Labels)) {
			continue
		}
		daemonSets = append(daemonSets, daemonSet)
	}
	if len(daemonSets) == 0 {
		err = fmt.Errorf("could not find daemon set for pod %s in namespace %s with labels: %v", pod.Name, pod.Namespace, pod.Labels)
	}
	return
}

// GetPodReplicaSets returns a list of ReplicaSets managing a pod. Returns an error only if no matching ReplicaSets are found.
func (s *StoreToReplicaSetLister) GetPodReplicaSets(pod *api.Pod) (rss []extensions.ReplicaSet, err error) {
	var selector labels.Selector
	var rs extensions.ReplicaSet

	if len(pod.Labels) == 0 {
		err = fmt.Errorf("no ReplicaSets found for pod %v because it has no labels", pod.Name)
		return
	}

	for _, m := range s.Store.List() {
		rs = *m.(*extensions.ReplicaSet)
		if rs.Namespace != pod.Namespace {
			continue
		}
		selector, err = unversioned.LabelSelectorAsSelector(rs.Spec.Selector)
		if err != nil {
			err = fmt.Errorf("invalid selector: %v", err)
			return
		}

		// If a ReplicaSet with a nil or empty selector creeps in, it should match nothing, not everything.
		if selector.Empty() || !selector.Matches(labels.Set(pod.Labels)) {
			continue
		}
		rss = append(rss, rs)
	}
	if len(rss) == 0 {
		err = fmt.Errorf("could not find ReplicaSet for pod %s in namespace %s with labels: %v", pod.Name, pod.Namespace, pod.Labels)
	}
	return
}

// GetPodControllers returns a list of replication controllers managing a pod. Returns an error only if no matching controllers are found.
func (s *StoreToReplicationControllerLister) GetPodControllers(pod *api.Pod) (controllers []api.ReplicationController, err error) {
	var selector labels.Selector
	var rc api.ReplicationController

	if len(pod.Labels) == 0 {
		err = fmt.Errorf("no controllers found for pod %v because it has no labels", pod.Name)
		return
	}

	key := &api.ReplicationController{ObjectMeta: api.ObjectMeta{Namespace: pod.Namespace}}
	items, err := s.Indexer.Index(NamespaceIndex, key)
	if err != nil {
		return
	}

	for _, m := range items {
		rc = *m.(*api.ReplicationController)
		labelSet := labels.Set(rc.Spec.Selector)
		selector = labels.Set(rc.Spec.Selector).AsSelector()

		// If an rc with a nil or empty selector creeps in, it should match nothing, not everything.
		if labelSet.AsSelector().Empty() || !selector.Matches(labels.Set(pod.Labels)) {
			continue
		}
		controllers = append(controllers, rc)
	}
	if len(controllers) == 0 {
		err = fmt.Errorf("could not find controller for pod %s in namespace %s with labels: %v", pod.Name, pod.Namespace, pod.Labels)
	}
	return
}

// Matcher returns a generic matcher for a given label and field selector.
func Matcher(label labels.Selector, field fields.Selector) generic.Matcher {
	return generic.MatcherFunc(func(obj runtime.Object) (bool, error) {
		sa, ok := obj.(*extensions.ThirdPartyResourceData)
		if !ok {
			return false, fmt.Errorf("not a ThirdPartyResourceData")
		}
		fields := SelectableFields(sa)
		return label.Matches(labels.Set(sa.Labels)) && field.Matches(fields), nil
	})
}

// MatchNamespace returns a generic matcher for a given label and field selector.
func MatchNamespace(label labels.Selector, field fields.Selector) generic.Matcher {
	return generic.MatcherFunc(func(obj runtime.Object) (bool, error) {
		namespaceObj, ok := obj.(*api.Namespace)
		if !ok {
			return false, fmt.Errorf("not a namespace")
		}
		fields := NamespaceToSelectableFields(namespaceObj)
		return label.Matches(labels.Set(namespaceObj.Labels)) && field.Matches(fields), nil
	})
}

// MatchPersistentVolume returns a generic matcher for a given label and field selector.
func MatchPersistentVolumes(label labels.Selector, field fields.Selector) generic.Matcher {
	return generic.MatcherFunc(func(obj runtime.Object) (bool, error) {
		persistentvolumeObj, ok := obj.(*api.PersistentVolume)
		if !ok {
			return false, fmt.Errorf("not a persistentvolume")
		}
		fields := PersistentVolumeToSelectableFields(persistentvolumeObj)
		return label.Matches(labels.Set(persistentvolumeObj.Labels)) && field.Matches(fields), nil
	})
}

func (s storeReplicaSetsNamespacer) List(selector labels.Selector) (rss []extensions.ReplicaSet, err error) {
	for _, c := range s.store.List() {
		rs := *(c.(*extensions.ReplicaSet))
		if s.namespace == api.NamespaceAll || s.namespace == rs.Namespace {
			if selector.Matches(labels.Set(rs.Labels)) {
				rss = append(rss, rs)
			}
		}
	}
	return
}

func (h *HeapsterMetricsClient) getCpuUtilizationForPods(namespace string, selector labels.Selector, podNames map[string]struct{}) (int64, time.Time, error) {
	metricPath := fmt.Sprintf("/apis/metrics/v1alpha1/namespaces/%s/pods", namespace)
	params := map[string]string{"labelSelector": selector.String()}

	resultRaw, err := h.client.Core().Services(h.heapsterNamespace).
		ProxyGet(h.heapsterScheme, h.heapsterService, h.heapsterPort, metricPath, params).
		DoRaw()
	if err != nil {
		return 0, time.Time{}, fmt.Errorf("failed to get pods metrics: %v", err)
	}

	glog.V(4).Infof("Heapster metrics result: %s", string(resultRaw))

	metrics := make([]metrics_api.PodMetrics, 0)
	err = json.Unmarshal(resultRaw, &metrics)
	if err != nil {
		return 0, time.Time{}, fmt.Errorf("failed to unmarshall heapster response: %v", err)
	}

	if len(metrics) != len(podNames) {
		return 0, time.Time{}, fmt.Errorf("metrics obtained for %d/%d of pods", len(metrics), len(podNames))
	}

	sum := int64(0)
	for _, m := range metrics {
		if _, found := podNames[m.Name]; found {
			for _, c := range m.Containers {
				cpu, found := c.Usage[v1.ResourceCPU]
				if !found {
					return 0, time.Time{}, fmt.Errorf("no cpu for container %v in pod %v/%v", c.Name, namespace, m.Name)
				}
				sum += cpu.MilliValue()
			}
		} else {
			return 0, time.Time{}, fmt.Errorf("not expected metrics for pod %v/%v", namespace, m.Name)
		}
	}

	return sum / int64(len(metrics)), metrics[0].Timestamp.Time, nil
}

// Validates the given template and ensures that it is in accordance with the desired selector.
func ValidatePodTemplateSpecForPetSet(template *api.PodTemplateSpec, selector labels.Selector, fldPath *field.Path) field.ErrorList {
	allErrs := field.ErrorList{}
	if template == nil {
		allErrs = append(allErrs, field.Required(fldPath, ""))
	} else {
		if !selector.Empty() {
			// Verify that the PetSet selector matches the labels in template.
			labels := labels.Set(template.Labels)
			if !selector.Matches(labels) {
				allErrs = append(allErrs, field.Invalid(fldPath.Child("metadata", "labels"), template.Labels, "`selector` does not match template `labels`"))
			}
		}
		// TODO: Add validation for PodSpec, currently this will check volumes, which we know will
		// fail. We should really check that the union of the given volumes and volumeClaims match
		// volume mounts in the containers.
		// allErrs = append(allErrs, apivalidation.ValidatePodTemplateSpec(template, fldPath)...)
		allErrs = append(allErrs, unversionedvalidation.ValidateLabels(template.Labels, fldPath.Child("labels"))...)
		allErrs = append(allErrs, apivalidation.ValidateAnnotations(template.Annotations, fldPath.Child("annotations"))...)
		allErrs = append(allErrs, apivalidation.ValidatePodSpecificAnnotations(template.Annotations, fldPath.Child("annotations"))...)
	}
	return allErrs
}