package minio

import (
	"context"
	"encoding/json"
	"fmt"
	"oc-datacenter/conf"

	oclib "cloud.o-forge.io/core/oc-lib"
	"github.com/minio/madmin-go/v4"
	"github.com/minio/minio-go/v7"
	"github.com/minio/minio-go/v7/pkg/credentials"
	v1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/rest"

	"github.com/necmettindev/randomstring"
)

type MinioService struct {
	Url              string
	RootKey          string
	RootSecret       string
	MinioAdminClient *madmin.AdminClient
}

type StatementEntry struct {
	Effect   string   `json:"Effect"`
	Action   []string `json:"Action"`
	Resource string   `json:"Resource"`
}

type PolicyDocument struct {
	Version   string           `json:"Version"`
	Statement []StatementEntry `json:"Statement"`
}

func NewMinioService(url string) *MinioService {
	return &MinioService{
		Url:        url,
		RootKey:    conf.GetConfig().MinioRootKey,
		RootSecret: conf.GetConfig().MinioRootSecret,
	}
}

func (m *MinioService) CreateClient() error {
	cred := credentials.NewStaticV4(m.RootKey, m.RootSecret, "")
	cli, err := madmin.NewWithOptions(m.Url, &madmin.Options{Creds: cred, Secure: false}) // Maybe in the future we should use the secure option ?
	if err != nil {
		return err
	}

	m.MinioAdminClient = cli
	return nil
}

func (m *MinioService) CreateCredentials(executionId string) (string, string, error) {

	policy := PolicyDocument{
		Version: "2012-10-17",
		Statement: []StatementEntry{
			{
				Effect:   "Allow",
				Action:   []string{"s3:GetObject", "s3:PutObject"},
				Resource: "arn:aws:s3:::" + executionId + "/*",
			},
		},
	}

	p, err := json.Marshal(policy)
	if err != nil {
		return "", "", err
	}

	randAccess, randSecret := getRandomCreds()

	req := madmin.AddServiceAccountReq{
		Policy:     p,
		TargetUser: m.RootKey,
		AccessKey:  randAccess,
		SecretKey:  randSecret,
	}

	res, err := m.MinioAdminClient.AddServiceAccount(context.Background(), req)
	if err != nil {
		return "", "", err
	}

	return res.AccessKey, res.SecretKey, nil

}

func getRandomCreds() (string, string) {
	opts := randomstring.GenerationOptions{
		Length: 20,
	}

	a, _ := randomstring.GenerateString(opts)

	opts.Length = 40
	s, _ := randomstring.GenerateString(opts)

	return a, s

}
func (m *MinioService) CreateMinioConfigMap(minioID string, executionId string, url string) error {
	config, err := rest.InClusterConfig()
	if err != nil {
		return err
	}

	clientset, err := kubernetes.NewForConfig(config)
	if err != nil {
		return err
	}

	configMap := &v1.ConfigMap{
		ObjectMeta: metav1.ObjectMeta{
			Name:      minioID + "artifact-repository",
			Namespace: executionId,
		},
		Data: map[string]string{
			minioID + "s3-local": fmt.Sprintf(`
s3:
  bucket: %s
  endpoint: %s
  insecure: true
  accessKeySecret:
    name: %s-secret-s3
    key: accesskey
  secretKeySecret:
    name: %s-secret-s3
    key: secretkey
`, minioID+"-"+executionId, url, minioID, minioID),
		},
	}

	existing, err := clientset.CoreV1().
		ConfigMaps(executionId).
		Get(context.Background(), minioID+"artifact-repository", metav1.GetOptions{})

	if err == nil {
		// Update
		existing.Data = configMap.Data
		_, err = clientset.CoreV1().
			ConfigMaps(executionId).
			Update(context.Background(), existing, metav1.UpdateOptions{})
	} else {
		// Create
		_, err = clientset.CoreV1().
			ConfigMaps(executionId).
			Create(context.Background(), configMap, metav1.CreateOptions{})
	}
	return nil
}

func (m *MinioService) CreateBucket(minioID string, executionId string) error {
	l := oclib.GetLogger()
	cred := credentials.NewStaticV4(m.RootKey, m.RootSecret, "")
	client, err := minio.New(m.Url, &minio.Options{
		Creds:  cred,
		Secure: false,
	})
	if err != nil {
		l.Error().Msg("Error when creating the minio client for the data plane")
		return err
	}

	err = client.MakeBucket(context.Background(), minioID+"-"+executionId, minio.MakeBucketOptions{})
	if err != nil {
		l.Error().Msg("Error when creating the bucket for namespace " + executionId)
		return err
	}

	l.Info().Msg("Created the bucket " + minioID + "-" + executionId + " on " + m.Url + " minio")
	return nil
}

// DeleteCredentials revokes a scoped Minio service account by its access key.
func (m *MinioService) DeleteCredentials(accessKey string) error {
	if err := m.MinioAdminClient.DeleteServiceAccount(context.Background(), accessKey); err != nil {
		return fmt.Errorf("DeleteCredentials: %w", err)
	}
	return nil
}

// DeleteBucket removes the execution bucket from Minio.
func (m *MinioService) DeleteBucket(minioID, executionId string) error {
	l := oclib.GetLogger()
	cred := credentials.NewStaticV4(m.RootKey, m.RootSecret, "")
	client, err := minio.New(m.Url, &minio.Options{Creds: cred, Secure: false})
	if err != nil {
		l.Error().Msg("Error when creating minio client for bucket deletion")
		return err
	}
	bucketName := minioID + "-" + executionId
	if err := client.RemoveBucket(context.Background(), bucketName); err != nil {
		l.Error().Msg("Error when deleting bucket " + bucketName)
		return err
	}
	l.Info().Msg("Deleted bucket " + bucketName + " on " + m.Url)
	return nil
}

// DeleteMinioConfigMap removes the artifact-repository ConfigMap from the execution namespace.
func (m *MinioService) DeleteMinioConfigMap(minioID, executionId string) error {
	cfg, err := rest.InClusterConfig()
	if err != nil {
		return err
	}
	clientset, err := kubernetes.NewForConfig(cfg)
	if err != nil {
		return err
	}
	return clientset.CoreV1().ConfigMaps(executionId).Delete(
		context.Background(), minioID+"artifact-repository", metav1.DeleteOptions{},
	)
}