package testing

import (
	"errors"
	"fmt"
	"strconv"

	apierrors "k8s.io/apimachinery/pkg/api/errors"
	"k8s.io/apimachinery/pkg/api/meta"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/apimachinery/pkg/util/validation/field"
	"k8s.io/client-go/testing"

	"sigs.k8s.io/controller-runtime/pkg/client/apiutil"
)

type versionedTracker struct {
	testing.ObjectTracker
	scheme *runtime.Scheme
}

func (t versionedTracker) Create(gvr schema.GroupVersionResource, obj runtime.Object, ns string) error {
	accessor, err := meta.Accessor(obj)
	if err != nil {
		return fmt.Errorf("failed to get accessor for object: %v", err)
	}
	if accessor.GetName() == "" {
		return apierrors.NewInvalid(
			obj.GetObjectKind().GroupVersionKind().GroupKind(),
			accessor.GetName(),
			field.ErrorList{field.Required(field.NewPath("metadata.name"), "name is required")})
	}
	if accessor.GetResourceVersion() != "" {
		return apierrors.NewBadRequest("resourceVersion can not be set for Create requests")
	}
	accessor.SetResourceVersion("1")
	if err := t.ObjectTracker.Create(gvr, obj, ns); err != nil {
		accessor.SetResourceVersion("")
		return err
	}
	return nil
}

func (t versionedTracker) Update(gvr schema.GroupVersionResource, obj runtime.Object, ns string) error {
	accessor, err := meta.Accessor(obj)
	if err != nil {
		return fmt.Errorf("failed to get accessor for object: %v", err)
	}

	if accessor.GetName() == "" {
		return apierrors.NewInvalid(
			obj.GetObjectKind().GroupVersionKind().GroupKind(),
			accessor.GetName(),
			field.ErrorList{field.Required(field.NewPath("metadata.name"), "name is required")})
	}

	gvk := obj.GetObjectKind().GroupVersionKind()
	if gvk.Empty() {
		gvk, err = apiutil.GVKForObject(obj, t.scheme)
		if err != nil {
			return err
		}
	}

	oldObject, err := t.ObjectTracker.Get(gvr, ns, accessor.GetName())
	if err != nil {
		// If the resource is not found and the resource allows create on update, issue a
		// create instead.
		if apierrors.IsNotFound(err) && allowsCreateOnUpdate(gvk) {
			return t.Create(gvr, obj, ns)
		}
		return err
	}

	oldAccessor, err := meta.Accessor(oldObject)
	if err != nil {
		return err
	}

	// If the new object does not have the resource version set and it allows unconditional update,
	// default it to the resource version of the existing resource
	if accessor.GetResourceVersion() == "" && allowsUnconditionalUpdate(gvk) {
		accessor.SetResourceVersion(oldAccessor.GetResourceVersion())
	}
	if accessor.GetResourceVersion() != oldAccessor.GetResourceVersion() {
		return apierrors.NewConflict(gvr.GroupResource(), accessor.GetName(), errors.New("object was modified"))
	}
	if oldAccessor.GetResourceVersion() == "" {
		oldAccessor.SetResourceVersion("0")
	}
	intResourceVersion, err := strconv.ParseUint(oldAccessor.GetResourceVersion(), 10, 64)
	if err != nil {
		return fmt.Errorf("can not convert resourceVersion %q to int: %v", oldAccessor.GetResourceVersion(), err)
	}
	intResourceVersion++
	accessor.SetResourceVersion(strconv.FormatUint(intResourceVersion, 10))
	if !accessor.GetDeletionTimestamp().IsZero() && len(accessor.GetFinalizers()) == 0 {
		return t.ObjectTracker.Delete(gvr, accessor.GetNamespace(), accessor.GetName())
	}
	return t.ObjectTracker.Update(gvr, obj, ns)
}

// nolint: gocritic // a func copied from controller-runtime/pkg/client/fake
func allowsUnconditionalUpdate(gvk schema.GroupVersionKind) bool {
	switch gvk.Group {
	case "apps":
		switch gvk.Kind {
		case "ControllerRevision", "DaemonSet", "Deployment", "ReplicaSet", "StatefulSet":
			return true
		}
	case "autoscaling":
		switch gvk.Kind {
		case "HorizontalPodAutoscaler":
			return true
		}
	case "batch":
		switch gvk.Kind {
		case "CronJob", "Job":
			return true
		}
	case "certificates":
		switch gvk.Kind {
		case "Certificates":
			return true
		}
	case "flowcontrol":
		switch gvk.Kind {
		case "FlowSchema", "PriorityLevelConfiguration":
			return true
		}
	case "networking":
		switch gvk.Kind {
		case "Ingress", "IngressClass", "NetworkPolicy":
			return true
		}
	case "policy":
		switch gvk.Kind {
		case "PodSecurityPolicy":
			return true
		}
	case "rbac":
		switch gvk.Kind {
		case "ClusterRole", "ClusterRoleBinding", "Role", "RoleBinding":
			return true
		}
	case "scheduling":
		switch gvk.Kind {
		case "PriorityClass":
			return true
		}
	case "settings":
		switch gvk.Kind {
		case "PodPreset":
			return true
		}
	case "storage":
		switch gvk.Kind {
		case "StorageClass":
			return true
		}
	case "":
		switch gvk.Kind {
		case "ConfigMap", "Endpoint", "Event", "LimitRange", "Namespace", "Node",
			"PersistentVolume", "PersistentVolumeClaim", "Pod", "PodTemplate",
			"ReplicationController", "ResourceQuota", "Secret", "Service",
			"ServiceAccount", "EndpointSlice":
			return true
		}
	}

	return false
}

// nolint: gocritic // a func copied from controller-runtime/pkg/client/fake
func allowsCreateOnUpdate(gvk schema.GroupVersionKind) bool {
	switch gvk.Group {
	case "coordination":
		switch gvk.Kind {
		case "Lease":
			return true
		}
	case "node":
		switch gvk.Kind {
		case "RuntimeClass":
			return true
		}
	case "rbac":
		switch gvk.Kind {
		case "ClusterRole", "ClusterRoleBinding", "Role", "RoleBinding":
			return true
		}
	case "":
		switch gvk.Kind {
		case "Endpoint", "Event", "LimitRange", "Service":
			return true
		}
	}

	return false
}