/*
Copyright © 2023 Alibaba Group Holding Ltd.

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 framework

import (
	"context"
	"fmt"
	"io"
	"net/http"
	"strings"
	"time"

	v1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/util/wait"
	"sigs.k8s.io/yaml"

	"github.com/alibaba/open-local/pkg/apis/storage"
)

func (f *Framework) GetCRD(ctx context.Context, name string) (*v1.CustomResourceDefinition, error) {
	crd, err := f.APIServerClient.ApiextensionsV1().CustomResourceDefinitions().Get(ctx, name, metav1.GetOptions{})
	if err != nil {
		return nil, fmt.Errorf("unable to get CRD with name %v: %w", name, err)
	}
	return crd, nil
}

func (f *Framework) ListCRDs(ctx context.Context) (*v1.CustomResourceDefinitionList, error) {
	crds, err := f.APIServerClient.ApiextensionsV1().CustomResourceDefinitions().List(ctx, metav1.ListOptions{})
	if err != nil {
		return nil, fmt.Errorf("unable to list CRDs: %w", err)
	}
	return crds, nil
}

func (f *Framework) CreateOrUpdateCRD(ctx context.Context, crd *v1.CustomResourceDefinition) error {
	c, err := f.APIServerClient.ApiextensionsV1().CustomResourceDefinitions().Get(ctx, crd.Name, metav1.GetOptions{})
	if err != nil && !apierrors.IsNotFound(err) {
		return fmt.Errorf("getting CRD %s: %w", crd.Spec.Names.Kind, err)
	}

	if apierrors.IsNotFound(err) {
		// CRD doesn't exists -> Create
		_, err := f.APIServerClient.ApiextensionsV1().CustomResourceDefinitions().Create(ctx, crd, metav1.CreateOptions{})
		if err != nil {
			return fmt.Errorf("create CRD %s: %w", crd.Spec.Names.Kind, err)
		}
	} else {
		// must set this field from existing CRD to prevent update fail
		crd.ObjectMeta.ResourceVersion = c.ObjectMeta.ResourceVersion

		// CRD already exists -> Update
		_, err := f.APIServerClient.ApiextensionsV1().CustomResourceDefinitions().Update(ctx, crd, metav1.UpdateOptions{})
		if err != nil {
			return fmt.Errorf("update CRD %s: %w", crd.Spec.Names.Kind, err)
		}
	}
	return nil
}

func (f *Framework) DeleteCRD(ctx context.Context, name string) error {
	err := f.APIServerClient.ApiextensionsV1().CustomResourceDefinitions().Delete(ctx, name, metav1.DeleteOptions{})
	if err != nil {
		return fmt.Errorf("unable to delete CRD with name %v: %w", name, err)
	}

	return nil
}

func (f *Framework) MakeCRD(source string) (*v1.CustomResourceDefinition, error) {
	manifest, err := SourceToIOReader(source)
	if err != nil {
		return nil, fmt.Errorf("get manifest from source %s: %w", source, err)
	}

	content, err := io.ReadAll(manifest)
	if err != nil {
		return nil, fmt.Errorf("get manifest content: %w", err)
	}

	crd := v1.CustomResourceDefinition{}
	err = yaml.Unmarshal(content, &crd)
	if err != nil {
		return nil, fmt.Errorf("unmarshal CRD asset file %s: %w", source, err)
	}

	return &crd, nil
}

func WaitForCRDReady(listFunc func(opts metav1.ListOptions) (runtime.Object, error)) error {
	err := wait.PollUntilWithContext(context.Background(), 3*time.Second, func(ctx context.Context) (bool, error) {
		_, err := listFunc(metav1.ListOptions{})
		if err != nil {
			if se, ok := err.(*apierrors.StatusError); ok {
				if se.Status().Code == http.StatusNotFound {
					return false, nil
				}
			}
			return false, fmt.Errorf("failed to list CRD: %w", err)
		}
		return true, nil
	})

	if err != nil {
		return fmt.Errorf("timed out waiting for Custom Resource: %w", err)
	}
	return nil
}

func (f *Framework) CreateOrUpdateCRDAndWaitUntilReady(ctx context.Context, crdName string, listFunc func(opts metav1.ListOptions) (runtime.Object, error)) error {
	crdName = strings.ToLower(crdName)
	group := storage.GroupName
	assetPath := f.exampleDir + "/config/" + group + "_" + crdName + ".yaml"

	crd, err := f.MakeCRD(assetPath)
	if err != nil {
		return fmt.Errorf("create CRD: %s from manifest: %s: %w", crdName, assetPath, err)
	}

	crd.ObjectMeta.Name = crd.Spec.Names.Plural + "." + group
	crd.Spec.Group = group

	err = f.CreateOrUpdateCRD(ctx, crd)
	if err != nil {
		return fmt.Errorf("create CRD %s on the apiserver: %w", crdName, err)
	}

	err = WaitForCRDReady(listFunc)
	if err != nil {
		return fmt.Errorf("%s CRD not ready: %w", crdName, err)
	}

	return nil
}
