/*
Copyright © The ESO Authors

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

	https://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 fortanix provides a Fortanix provider implementation.
package fortanix

import (
	"context"
	"errors"
	"fmt"
	"net/http"

	"github.com/fortanix/sdkms-client-go/sdkms"
	kubeclient "sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"

	esv1 "github.com/external-secrets/external-secrets/apis/externalsecrets/v1"
	"github.com/external-secrets/external-secrets/runtime/esutils"
	"github.com/external-secrets/external-secrets/runtime/esutils/resolvers"
)

// Provider implements provider interface for Fortanix Key Management.
type Provider struct{}

const (
	errCannotResolveSecretKeyRef     = "cannot resolve secret key ref: %w"
	errStoreIsNil                    = "store is nil"
	errNoStoreTypeOrWrongStoreType   = "no store type or wrong store type"
	errAPIKeyIsRequired              = "apiKey is required"
	errAPIKeySecretRefIsRequired     = "apiKey.secretRef is required"
	errAPIKeySecretRefNameIsRequired = "apiKey.secretRef.name is required"
	errAPIKeySecretRefKeyIsRequired  = "apiKey.secretRef.key is required"
)

var _ esv1.Provider = &Provider{}

// Capabilities returns the provider supported capabilities (ReadOnly, WriteOnly, ReadWrite).
func (p *Provider) Capabilities() esv1.SecretStoreCapabilities {
	return esv1.SecretStoreReadOnly
}

// NewClient creates a new Fortanix Key Management client.
func (p *Provider) NewClient(ctx context.Context, store esv1.GenericStore, kube kubeclient.Client, namespace string) (esv1.SecretsClient, error) {
	config, err := getConfig(store)
	if err != nil {
		return nil, err
	}

	apiKey, err := resolvers.SecretKeyRef(ctx, kube, store.GetKind(), namespace, config.APIKey.SecretRef)
	if err != nil {
		return nil, fmt.Errorf(errCannotResolveSecretKeyRef, err)
	}

	sdkmsClient := sdkms.Client{
		HTTPClient: http.DefaultClient,
		Auth:       sdkms.APIKey(apiKey),
		Endpoint:   config.APIURL,
	}

	return &client{
		sdkms: sdkmsClient,
	}, nil
}

// ValidateStore validates the Fortanix Key Management store configuration.
func (p *Provider) ValidateStore(store esv1.GenericStore) (admission.Warnings, error) {
	_, err := getConfig(store)
	return nil, err
}

func getConfig(store esv1.GenericStore) (*esv1.FortanixProvider, error) {
	if store == nil {
		return nil, errors.New(errStoreIsNil)
	}

	spec := store.GetSpec()
	if spec == nil || spec.Provider == nil || spec.Provider.Fortanix == nil {
		return nil, errors.New(errNoStoreTypeOrWrongStoreType)
	}

	config := spec.Provider.Fortanix

	if config.APIURL == "" {
		config.APIURL = "https://sdkms.fortanix.com"
	}

	err := validateSecretStoreRef(store, config.APIKey)
	if err != nil {
		return nil, err
	}

	return config, nil
}

func validateSecretStoreRef(store esv1.GenericStore, ref *esv1.FortanixProviderSecretRef) error {
	if ref == nil {
		return errors.New(errAPIKeyIsRequired)
	}

	if ref.SecretRef == nil {
		return errors.New(errAPIKeySecretRefIsRequired)
	}

	if ref.SecretRef.Name == "" {
		return errors.New(errAPIKeySecretRefNameIsRequired)
	}

	if ref.SecretRef.Key == "" {
		return errors.New(errAPIKeySecretRefKeyIsRequired)
	}

	return esutils.ValidateReferentSecretSelector(store, *ref.SecretRef)
}

// NewProvider creates a new Provider instance.
func NewProvider() esv1.Provider {
	return &Provider{}
}

// ProviderSpec returns the provider specification for registration.
func ProviderSpec() *esv1.SecretStoreProvider {
	return &esv1.SecretStoreProvider{
		Fortanix: &esv1.FortanixProvider{},
	}
}

// MaintenanceStatus returns the maintenance status of the provider.
func MaintenanceStatus() esv1.MaintenanceStatus {
	return esv1.MaintenanceStatusMaintained
}
