package asyncappbox

import (
	"context"
	"fmt"
	"time"

	"github.com/go-logr/logr"
	"github.com/tidbcloud/infra-provider/pkg/cloud/gcp"
	"github.com/tidbcloud/infra-provider/pkg/deploy"
	"github.com/tidbcloud/infra-provider/pkg/k8s"
	"github.com/tidbcloud/infra-provider/pkg/namer"
	"github.com/tidbcloud/infra-provider/regional-server/api/v1alpha1"
	"github.com/tidbcloud/infra-provider/regional-server/pkg/common/utils"
	"github.com/tidbcloud/infra-provider/regional-server/pkg/config"
	"github.com/tidbcloud/infra-provider/regional-server/pkg/controllers"
	"github.com/tidbcloud/infra-provider/regional-server/pkg/controllers/appbox/task"
	"github.com/tidbcloud/infra-provider/regional-server/pkg/resourcemanager/appbox"
	"github.com/tidbcloud/infra-provider/regional-server/pkg/resourcemanager/vpc"
	corev1 "k8s.io/api/core/v1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/client-go/tools/record"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/builder"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/controller"
	"sigs.k8s.io/controller-runtime/pkg/log"
	"sigs.k8s.io/controller-runtime/pkg/predicate"
)

const (
	defaultRequeueTime = 30 * time.Second
)

var requeue = ctrl.Result{Requeue: true, RequeueAfter: defaultRequeueTime}

type AsyncAPPBoxReconciler struct {
	client.Client
	Log           logr.Logger
	Scheme        *runtime.Scheme
	Config        config.RootConfig
	Manager       *controllers.Manager
	EventRecorder record.EventRecorder
	VPCR          vpc.VPCReader
	Provider      string
	APPBoxRW      appbox.APPBoxReaderWriter
	GCPCli        gcp.Client
}

func NewAsyncAPPBoxReconciler(
	client client.Client,
	log logr.Logger, scheme *runtime.Scheme,
	config config.RootConfig,
	manager *controllers.Manager,
	recorder record.EventRecorder,
	provider string,
	gcpCli gcp.Client,
) *AsyncAPPBoxReconciler {
	return &AsyncAPPBoxReconciler{
		Client:        client,
		Log:           log,
		Scheme:        scheme,
		Config:        config,
		Manager:       manager,
		EventRecorder: recorder,
		Provider:      provider,
		APPBoxRW:      appbox.NewAPPBoxReaderWriter(client),
		VPCR:          vpc.NewVPCReader(client),
		GCPCli:        gcpCli,
	}
}

func (r *AsyncAPPBoxReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
	logger := r.Log.WithValues("APPBox", req.NamespacedName)
	ctx = log.IntoContext(ctx, logger)
	logger.Info("Start Reconciling AsyncAPPBox")
	defer func() {
		logger.Info("Finish AsyncAPPBox Reconcile")
	}()
	var appBox v1alpha1.APPBox
	if err := r.APPBoxRW.Get(ctx, req.NamespacedName, &appBox); err != nil {
		if apierrors.IsNotFound(err) {
			r.Log.Info("APPBox not found", "name", req.Name, "namespace", req.Namespace)
			return ctrl.Result{}, nil
		}
		return requeue, fmt.Errorf("unable to get APPBox : %v", err)
	}
	// do nothing if the cr is pause
	if utils.IsPaused(appBox.GetObjectMeta()) {
		logger.Info("reconciliation is paused either through the pause annotation",
			"annotation", v1alpha1.AnnotationKeyReconciliationPaused,
			"appbox", req.NamespacedName.String(),
		)
		r.EventRecorder.Event(&appBox, "ReconciliationPaused", "reconciliation is paused through the pause annotation", v1alpha1.AnnotationKeyReconciliationPaused)
		return ctrl.Result{}, nil
	}

	var vpc v1alpha1.VPC
	if err := r.VPCR.Get(ctx, types.NamespacedName{Name: appBox.Spec.VPCRef.Name, Namespace: appBox.Spec.VPCRef.Namespace}, &vpc); err != nil {
		return requeue, fmt.Errorf("unable to get VPC: %v", err)
	}

	providerType := appBox.Spec.Provider
	if providerType != r.Provider {
		logger.Info("Mismatched provider", "expect", r.Provider, "got", providerType)
	}

	c, err := (&task.Context{
		Local:    k8s.NewMutClientWithOwner(r.Client, appBox.DeepCopy(), namer.NewNamer()).Client(),
		Config:   r.Config,
		APPBox:   &appBox,
		VPC:      &vpc,
		VPCR:     r.VPCR,
		Logger:   r.Log,
		APPBoxRW: r.APPBoxRW,
	}).Default()
	if err != nil {
		return requeue, fmt.Errorf("failed to create a new context: %v", err)
	}

	tasks := GetAsyncAPPBoxTasks(r, c)
	d := deploy.NewDeployer(tasks, nil, logger)

	var res ctrl.Result
	if appBox.DeletionTimestamp.IsZero() {
		res, err = updateCreate(ctx, d.Deploy(ctx))
	}
	if err == nil {
		r.EventRecorder.Event(&appBox, corev1.EventTypeNormal, "AsyncTaskReconcileSuccess", "")
	} else {
		r.EventRecorder.Event(&appBox, corev1.EventTypeWarning, "AsyncTaskReconcileFailed", err.Error())
	}
	return res, err
}

func updateCreate(ctx context.Context, results []deploy.Result) (res ctrl.Result, err error) {
	var retriableErr error
	res, err, retriableErr = deploy.MinRequeue(results)
	if err == nil && retriableErr == nil {
		log.FromContext(ctx).Info("reconcile success")
		return res, nil
	}

	if retriableErr != nil {
		log.FromContext(ctx).Info("retriable error", "error", retriableErr)
		if err == nil {
			err = retriableErr
		}
	}
	return res, err
}

func (r *AsyncAPPBoxReconciler) SetupWithManager(mgr ctrl.Manager, pds ...predicate.Predicate) error {
	return ctrl.NewControllerManagedBy(mgr).
		Named("async_appbox").
		For(&v1alpha1.APPBox{}, builder.WithPredicates(pds...)).
		WithOptions(controller.Options{RateLimiter: k8s.RetryLimiter, MaxConcurrentReconciles: 5}).
		WithEventFilter(predicate.Or(
			predicate.GenerationChangedPredicate{},
			predicate.LabelChangedPredicate{},
			controllers.AnnotationChangedPredicate{})).
		Complete(r)
}