/*
Copyright © 2025 ESO Maintainer Team

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 doppler

import (
	"context"
	"errors"
	"fmt"
	"os"
	"strconv"
	"time"

	kclient "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"
	dclient "github.com/external-secrets/external-secrets/providers/v1/doppler/client"
	"github.com/external-secrets/external-secrets/runtime/esutils"
)

const (
	errNewClient    = "unable to create DopplerClient : %s"
	errInvalidStore = "invalid store: %s"
	errDopplerStore = "missing or invalid Doppler SecretStore"
)

// Provider is a Doppler secrets provider implementing NewClient and ValidateStore for the esv1.Provider interface.
type Provider struct{}

// https://github.com/external-secrets/external-secrets/issues/644
var _ esv1.SecretsClient = &Client{}
var _ esv1.Provider = &Provider{}

// Capabilities returns the provider's supported capabilities.
func (p *Provider) Capabilities() esv1.SecretStoreCapabilities {
	return esv1.SecretStoreReadOnly
}

// NewClient creates a new Doppler client.
func (p *Provider) NewClient(ctx context.Context, store esv1.GenericStore, kube kclient.Client, namespace string) (esv1.SecretsClient, error) {
	storeSpec := store.GetSpec()

	if storeSpec == nil || storeSpec.Provider == nil || storeSpec.Provider.Doppler == nil {
		return nil, errors.New(errDopplerStore)
	}

	dopplerStoreSpec := storeSpec.Provider.Doppler

	// Default Key to dopplerToken if not specified
	if dopplerStoreSpec.Auth.SecretRef.DopplerToken.Key == "" {
		storeSpec.Provider.Doppler.Auth.SecretRef.DopplerToken.Key = "dopplerToken"
	}

	client := &Client{
		kube:      kube,
		store:     dopplerStoreSpec,
		namespace: namespace,
		storeKind: store.GetObjectKind().GroupVersionKind().Kind,
	}

	if err := client.setAuth(ctx); err != nil {
		return nil, err
	}

	doppler, err := dclient.NewDopplerClient(client.dopplerToken)
	if err != nil {
		return nil, fmt.Errorf(errNewClient, err)
	}

	if customBaseURL, found := os.LookupEnv(customBaseURLEnvVar); found {
		if err := doppler.SetBaseURL(customBaseURL); err != nil {
			return nil, fmt.Errorf(errNewClient, err)
		}
	}

	if customVerifyTLS, found := os.LookupEnv(verifyTLSOverrideEnvVar); found {
		customVerifyTLS, err := strconv.ParseBool(customVerifyTLS)
		if err == nil {
			doppler.VerifyTLS = customVerifyTLS
		}
	}

	// Wrap the Doppler client with retry logic if retrySettings are configured
	wrappedClient, err := p.setRetrySettings(doppler, storeSpec)
	if err != nil {
		return nil, err
	}

	client.doppler = wrappedClient
	client.project = client.store.Project
	client.config = client.store.Config
	client.nameTransformer = client.store.NameTransformer
	client.format = client.store.Format

	return client, nil
}

// ValidateStore validates the Doppler provider configuration.
func (p *Provider) ValidateStore(store esv1.GenericStore) (admission.Warnings, error) {
	storeSpec := store.GetSpec()
	dopplerStoreSpec := storeSpec.Provider.Doppler
	dopplerTokenSecretRef := dopplerStoreSpec.Auth.SecretRef.DopplerToken
	if err := esutils.ValidateSecretSelector(store, dopplerTokenSecretRef); err != nil {
		return nil, fmt.Errorf(errInvalidStore, err)
	}

	if dopplerTokenSecretRef.Name == "" {
		return nil, fmt.Errorf(errInvalidStore, "dopplerToken.name cannot be empty")
	}

	return nil, nil
}

func (p *Provider) setRetrySettings(doppler *dclient.DopplerClient, storeSpec *esv1.SecretStoreSpec) (SecretsClientInterface, error) {
	if storeSpec.RetrySettings == nil {
		return doppler, nil
	}

	maxRetries := 3 // default value
	retryInterval := time.Duration(0)

	if storeSpec.RetrySettings.MaxRetries != nil {
		maxRetries = int(*storeSpec.RetrySettings.MaxRetries)
	}

	if storeSpec.RetrySettings.RetryInterval != nil {
		var err error
		retryInterval, err = time.ParseDuration(*storeSpec.RetrySettings.RetryInterval)
		if err != nil {
			return nil, fmt.Errorf(errNewClient, fmt.Errorf("invalid retry interval: %w", err))
		}
	}

	return newRetryableClient(doppler, maxRetries, retryInterval), nil
}

// 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{
		Doppler: &esv1.DopplerProvider{},
	}
}

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