package broker

import (
	"context"
	cachev1alpha1 "github.com/operator-sdk-samples/rocketmq-operator/pkg/apis/cache/v1alpha1"
	cons "github.com/operator-sdk-samples/rocketmq-operator/pkg/constants"
	appsv1 "k8s.io/api/apps/v1"
	corev1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/types"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/controller"
	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
	"sigs.k8s.io/controller-runtime/pkg/handler"
	"sigs.k8s.io/controller-runtime/pkg/manager"
	"sigs.k8s.io/controller-runtime/pkg/reconcile"
	logf "sigs.k8s.io/controller-runtime/pkg/runtime/log"
	"sigs.k8s.io/controller-runtime/pkg/source"
	"strconv"
	"time"
)

var log = logf.Log.WithName("controller_broker")

// Add creates a new Broker Controller and adds it to the Manager. The Manager will set fields on the Controller
// and Start it when the Manager is Started.
func Add(mgr manager.Manager) error {
	return add(mgr, newReconciler(mgr))
}

// newReconciler returns a new reconcile.Reconciler
func newReconciler(mgr manager.Manager) reconcile.Reconciler {
	return &ReconcileBroker{client: mgr.GetClient(), scheme: mgr.GetScheme()}
}

// add adds a new Controller to mgr with r as the reconcile.Reconciler
func add(mgr manager.Manager, r reconcile.Reconciler) error {
	// Create a new controller
	c, err := controller.New("broker-controller", mgr, controller.Options{Reconciler: r})
	if err != nil {
		return err
	}

	// Watch for changes to primary resource Broker
	err = c.Watch(&source.Kind{Type: &cachev1alpha1.Broker{}}, &handler.EnqueueRequestForObject{})
	if err != nil {
		return err
	}

	// TODO(user): Modify this to be the types you create that are owned by the primary resource
	// Watch for changes to secondary resource Pods and requeue the owner Broker
	err = c.Watch(&source.Kind{Type: &appsv1.Deployment{}}, &handler.EnqueueRequestForOwner{
		IsController: true,
		OwnerType:    &cachev1alpha1.Broker{},
	})
	if err != nil {
		return err
	}

	return nil
}

var _ reconcile.Reconciler = &ReconcileBroker{}

// ReconcileBroker reconciles a Broker object
type ReconcileBroker struct {
	// TODO: Clarify the split client
	// This client, initialized using mgr.Client() above, is a split client
	// that reads objects from the cache and writes to the apiserver
	client client.Client
	scheme *runtime.Scheme
}

// Reconcile reads that state of the cluster for a Broker object and makes changes based on the state read
// and what is in the Broker.Spec
// TODO(user): Modify this Reconcile function to implement your Controller logic.  This example creates
// a Broker Deployment for each Broker CR
// Note:
// The Controller will requeue the Request to be processed again if the returned error is non-nil or
// Result.Requeue is true, otherwise upon completion it will remove the work from the queue.
func (r *ReconcileBroker) Reconcile(request reconcile.Request) (reconcile.Result, error) {
	reqLogger := log.WithValues("Request.Namespace", request.Namespace, "Request.Name", request.Name)
	reqLogger.Info("Reconciling Broker.")

	// Fetch the Broker instance
	broker := &cachev1alpha1.Broker{}
	err := r.client.Get(context.TODO(), request.NamespacedName, broker)
	if err != nil {
		if errors.IsNotFound(err) {
			// Request object not found, could have been deleted after reconcile request.
			// Owned objects are automatically garbage collected. For additional cleanup logic use finalizers.
			// Return and don't requeue
			reqLogger.Info("Broker resource not found. Ignoring since object must be deleted.")
			return reconcile.Result{}, nil
		}
		// Error reading the object - requeue the request.
		reqLogger.Error(err, "Failed to get Broker.")
		return reconcile.Result{}, err
	}

	// Check if the deployment already exists, if not create a new one
	found := &appsv1.Deployment{}

	brokerGroupNum := int(broker.Spec.Size)
	slavePerGroup := broker.Spec.SlavePerGroup
	reqLogger.Info("brokerGroupNum=" + strconv.Itoa(brokerGroupNum) + ", slavePerGroup=" + strconv.Itoa(slavePerGroup))

	for brokerClusterIndex := 0; brokerClusterIndex < brokerGroupNum; brokerClusterIndex++ {
		reqLogger.Info("Check Broker cluster " + strconv.Itoa(brokerClusterIndex+1) + "/" + strconv.Itoa(brokerGroupNum))
		dep := r.deploymentForMasterBroker(broker, brokerClusterIndex)
		err = r.client.Get(context.TODO(), types.NamespacedName{Name: dep.Name, Namespace: dep.Namespace}, found)
		if err != nil && errors.IsNotFound(err) {
			reqLogger.Info("Creating a new Master Broker Deployment.", "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
			err = r.client.Create(context.TODO(), dep)
			for slaveIndex := 1; slaveIndex <= slavePerGroup; slaveIndex++ {
				reqLogger.Info("Check Slave Broker of cluster-" + strconv.Itoa(brokerClusterIndex) + " " + strconv.Itoa(slaveIndex) + "/" + strconv.Itoa(slavePerGroup))
				slaveDep := r.deploymentForSlaveBroker(broker, brokerClusterIndex, slaveIndex)
				err = r.client.Get(context.TODO(), types.NamespacedName{Name: slaveDep.Name, Namespace: slaveDep.Namespace}, found)
				if err != nil && errors.IsNotFound(err) {
					reqLogger.Info("Creating a new Slave Broker Deployment.", "Deployment.Namespace", slaveDep.Namespace, "Deployment.Name", slaveDep.Name)
					err = r.client.Create(context.TODO(), slaveDep)
					if err != nil {
						reqLogger.Error(err, "Failed to create new Deployment of broker-"+strconv.Itoa(brokerClusterIndex)+"-slave-"+strconv.Itoa(slaveIndex), "Deployment.Namespace", slaveDep.Namespace, "Deployment.Name", slaveDep.Name)
					}
				} else if err != nil {
					reqLogger.Error(err, "Failed to get broker slave Deployment.")
				}
			}
			if err != nil {
				reqLogger.Error(err, "Failed to create new Deployment of "+cons.BrokerClusterPrefix+strconv.Itoa(brokerClusterIndex), "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
			}
		} else if err != nil {
			reqLogger.Error(err, "Failed to get broker master Deployment.")
		}
	}

	// Ensure the deployment size is the same as the spec
	//size := broker.Spec.Size
	//if *found.Spec.Replicas != size {
	//	found.Spec.Replicas = &size
	//	err = r.client.Update(context.TODO(), found)
	//	if err != nil {
	//		reqLogger.Error(err, "Failed to update Deployment.", "Deployment.Namespace", found.Namespace, "Deployment.Name", found.Name)
	//		return reconcile.Result{}, err
	//	}
	//	// Spec updated - return and requeue
	//	return reconcile.Result{Requeue: true}, nil
	//}

	// Update the Broker status with the pod names
	// List the pods for this broker's deployment

	//podList := &corev1.PodList{}
	//labelSelector := labels.SelectorFromSet(labelsForBroker(broker.Name))
	//listOps := &client.ListOptions{
	//	Namespace:     broker.Namespace,
	//	LabelSelector: labelSelector,
	//}
	//err = r.client.List(context.TODO(), listOps, podList)
	//if err != nil {
	//	reqLogger.Error(err, "Failed to list pods.", "Broker.Namespace", broker.Namespace, "Broker.Name", broker.Name)
	//	return reconcile.Result{}, err
	//}
	//podNames := getPodNames(podList.Items)
	//
	//// Update status.Nodes if needed
	//if !reflect.DeepEqual(podNames, broker.Status.Nodes) {
	//	broker.Status.Nodes = podNames
	//	err := r.client.Status().Update(context.TODO(), broker)
	//	if err != nil {
	//		reqLogger.Error(err, "Failed to update Broker status.")
	//		return reconcile.Result{}, err
	//	}
	//}

	return reconcile.Result{true, time.Duration(3) * time.Second}, nil
}

// deploymentForBroker returns a master broker Deployment object
func (r *ReconcileBroker) deploymentForMasterBroker(m *cachev1alpha1.Broker, brokerClusterIndex int) *appsv1.Deployment {
	ls := labelsForBroker(m.Name)
	var a int32 = 1
	var c = &a
	dep := &appsv1.Deployment{
		ObjectMeta: metav1.ObjectMeta{
			Name:      m.Name + "-" + strconv.Itoa(brokerClusterIndex) + "-master",
			Namespace: m.Namespace,
		},
		Spec: appsv1.DeploymentSpec{
			Replicas: c,
			Selector: &metav1.LabelSelector{
				MatchLabels: ls,
			},
			Template: corev1.PodTemplateSpec{
				ObjectMeta: metav1.ObjectMeta{
					Labels: ls,
				},
				Spec: corev1.PodSpec{
					Containers: []corev1.Container{{
						Image:           m.Spec.BrokerImage,
						Name:            cons.MasterBrokerContainerNamePrefix + strconv.Itoa(brokerClusterIndex),
						ImagePullPolicy: m.Spec.ImagePullPolicy,
						Env: []corev1.EnvVar{{
							Name:  "NAMESRV_ADDRESS",
							Value: m.Spec.NameServers,
						}, {
							Name:  "REPLICATION_MODE",
							Value: m.Spec.ReplicationMode,
						}, {
							Name:  "BROKER_ID",
							Value: "0",
						}, {
							Name:  "BROKER_CLUSTER_NAME",
							Value: cons.BrokerClusterPrefix + strconv.Itoa(brokerClusterIndex),
						}},
						//Command: []string{"cmd", "-m=64", "-o", "modern", "-v"},
						Ports: []corev1.ContainerPort{{
							ContainerPort: 10909,
							Name:          "10909port",
						}, {
							ContainerPort: 10911,
							Name:          "10911port",
						}, {
							ContainerPort: 10912,
							Name:          "10912port",
						}},
					}},
				},
			},
		},
	}
	// Set Broker instance as the owner and controller
	controllerutil.SetControllerReference(m, dep, r.scheme)

	return dep

}

// deploymentForBroker returns a slave broker Deployment object
func (r *ReconcileBroker) deploymentForSlaveBroker(m *cachev1alpha1.Broker, brokerClusterIndex int, slaveIndex int) *appsv1.Deployment {
	ls := labelsForBroker(m.Name)
	var a int32 = 1
	var c = &a
	dep := &appsv1.Deployment{
		ObjectMeta: metav1.ObjectMeta{
			Name:      m.Name + "-" + strconv.Itoa(brokerClusterIndex) + "-slave-" + strconv.Itoa(slaveIndex),
			Namespace: m.Namespace,
		},
		Spec: appsv1.DeploymentSpec{
			Replicas: c,
			Selector: &metav1.LabelSelector{
				MatchLabels: ls,
			},
			Template: corev1.PodTemplateSpec{
				ObjectMeta: metav1.ObjectMeta{
					Labels: ls,
				},
				Spec: corev1.PodSpec{
					Containers: []corev1.Container{{
						Image:           m.Spec.BrokerImage,
						Name:            cons.SlaveBrokerContainerNamePrefix + strconv.Itoa(brokerClusterIndex),
						ImagePullPolicy: m.Spec.ImagePullPolicy,
						Env: []corev1.EnvVar{{
							Name:  "NAMESRV_ADDRESS",
							Value: m.Spec.NameServers,
						}, {
							Name:  "REPLICATION_MODE",
							Value: m.Spec.ReplicationMode,
						}, {
							Name:  "BROKER_ID",
							Value: strconv.Itoa(slaveIndex),
						}, {
							Name:  "BROKER_CLUSTER_NAME",
							Value: cons.BrokerClusterPrefix + strconv.Itoa(brokerClusterIndex),
						}},
						//Command: []string{"cmd", "-m=64", "-o", "modern", "-v"},
						Ports: []corev1.ContainerPort{{
							ContainerPort: 10909,
							Name:          "10909port",
						}, {
							ContainerPort: 10911,
							Name:          "10911port",
						}, {
							ContainerPort: 10912,
							Name:          "10912port",
						}},
					}},
				},
			},
		},
	}
	// Set Broker instance as the owner and controller
	controllerutil.SetControllerReference(m, dep, r.scheme)

	return dep

}

// labelsForBroker returns the labels for selecting the resources
// belonging to the given broker CR name.
func labelsForBroker(name string) map[string]string {
	return map[string]string{"app": "broker", "broker_cr": name}
}

// getPodNames returns the pod names of the array of pods passed in
func getPodNames(pods []corev1.Pod) []string {
	var podNames []string
	for _, pod := range pods {
		podNames = append(podNames, pod.Name)
	}
	return podNames
}