package client

import (
	"os"

	"github.com/1Panel-dev/1Panel/backend/constant"
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/awserr"
	"github.com/aws/aws-sdk-go/aws/credentials"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/s3"
	"github.com/aws/aws-sdk-go/service/s3/s3manager"
)

type s3Client struct {
	scType string
	Vars   map[string]interface{}
	Sess   session.Session
}

func NewS3Client(vars map[string]interface{}) (*s3Client, error) {
	var accessKey string
	var secretKey string
	var endpoint string
	var scType string
	var region string
	if _, ok := vars["accessKey"]; ok {
		accessKey = vars["accessKey"].(string)
	} else {
		return nil, constant.ErrInvalidParams
	}
	if _, ok := vars["secretKey"]; ok {
		secretKey = vars["secretKey"].(string)
	} else {
		return nil, constant.ErrInvalidParams
	}
	if _, ok := vars["scType"]; ok {
		scType = vars["scType"].(string)
	} else {
		scType = "Standard"
	}
	if _, ok := vars["endpoint"]; ok {
		endpoint = vars["endpoint"].(string)
	} else {
		return nil, constant.ErrInvalidParams
	}
	if _, ok := vars["region"]; ok {
		region = vars["region"].(string)
	} else {
		return nil, constant.ErrInvalidParams
	}
	sess, err := session.NewSession(&aws.Config{
		Credentials:      credentials.NewStaticCredentials(accessKey, secretKey, ""),
		Endpoint:         aws.String(endpoint),
		Region:           aws.String(region),
		DisableSSL:       aws.Bool(true),
		S3ForcePathStyle: aws.Bool(false),
	})
	if err != nil {
		return nil, err
	}
	return &s3Client{
		scType: scType,
		Vars:   vars,
		Sess:   *sess,
	}, nil
}

func (s3C s3Client) ListBuckets() ([]interface{}, error) {
	var result []interface{}
	svc := s3.New(&s3C.Sess)
	res, err := svc.ListBuckets(nil)
	if err != nil {
		return nil, err
	}
	for _, b := range res.Buckets {
		result = append(result, b.Name)
	}
	return result, nil
}

func (s3C s3Client) Exist(path string) (bool, error) {
	bucket, err := s3C.getBucket()
	if err != nil {
		return false, err
	}
	svc := s3.New(&s3C.Sess)
	_, err = svc.HeadObject(&s3.HeadObjectInput{
		Bucket: &bucket,
		Key:    &path,
	})
	if err != nil {
		if aerr, ok := err.(awserr.RequestFailure); ok {
			if aerr.StatusCode() == 404 {
				return false, nil
			}
		} else {
			return false, aerr
		}
	}
	return true, nil
}

func (s3C s3Client) Delete(path string) (bool, error) {
	bucket, err := s3C.getBucket()
	if err != nil {
		return false, err
	}
	svc := s3.New(&s3C.Sess)
	_, err = svc.DeleteObject(&s3.DeleteObjectInput{Bucket: aws.String(bucket), Key: aws.String(path)})
	if err != nil {
		return false, err
	}
	err = svc.WaitUntilObjectNotExists(&s3.HeadObjectInput{
		Bucket: aws.String(bucket),
		Key:    aws.String(path),
	})
	if err != nil {
		return false, err
	}
	return true, nil
}

func (s3C s3Client) Upload(src, target string) (bool, error) {
	bucket, err := s3C.getBucket()
	if err != nil {
		return false, err
	}
	file, err := os.Open(src)
	if err != nil {
		return false, err
	}
	defer file.Close()

	uploader := s3manager.NewUploader(&s3C.Sess)
	_, err = uploader.Upload(&s3manager.UploadInput{
		Bucket:       aws.String(bucket),
		Key:          aws.String(target),
		Body:         file,
		StorageClass: &s3C.scType,
	})
	if err != nil {
		return false, err
	}
	return true, nil
}

func (s3C s3Client) Download(src, target string) (bool, error) {
	bucket, err := s3C.getBucket()
	if err != nil {
		return false, err
	}
	_, err = os.Stat(target)
	if err != nil {
		if os.IsNotExist(err) {
			os.Remove(target)
		} else {
			return false, err
		}
	}
	file, err := os.Create(target)
	if err != nil {
		return false, err
	}
	defer file.Close()
	downloader := s3manager.NewDownloader(&s3C.Sess)
	_, err = downloader.Download(file,
		&s3.GetObjectInput{
			Bucket: aws.String(bucket),
			Key:    aws.String(src),
		})
	if err != nil {
		os.Remove(target)
		return false, err
	}
	return true, nil
}

func (s3C *s3Client) getBucket() (string, error) {
	if _, ok := s3C.Vars["bucket"]; ok {
		return s3C.Vars["bucket"].(string), nil
	} else {
		return "", constant.ErrInvalidParams
	}
}

func (s3C *s3Client) ListObjects(prefix string) ([]string, error) {
	bucket, err := s3C.getBucket()
	if err != nil {
		return nil, constant.ErrInvalidParams
	}
	svc := s3.New(&s3C.Sess)
	var result []string
	if err := svc.ListObjectsPages(&s3.ListObjectsInput{
		Bucket: &bucket,
		Prefix: &prefix,
	}, func(p *s3.ListObjectsOutput, last bool) (shouldContinue bool) {
		for _, obj := range p.Contents {
			result = append(result, *obj.Key)
		}
		return true
	}); err != nil {
		return nil, err
	}
	return result, nil
}