package storage

import (
	"context"
	"errors"
	"fmt"
	"net/http"
	"net/url"
	"strings"
	"time"

	"github.com/tencentyun/cos-go-sdk-v5"
)

var _ ObjectStorage = (*storageCos)(nil)

type storageCos struct {
	client *cos.Client

	host         string
	accessKey    string
	accessSecret string
	bucket       string
}

func newCosStorage(host, accessKey, accessSecret string) (ObjectStorage, error) {
	parts := strings.Split(host, ".")
	if len(parts) != 5 {
		return nil, errors.New("invalid cos host")
	}
	parts = strings.Split(parts[0], "-")
	if len(parts) != 2 {
		return nil, errors.New("invalid cos host")
	}
	bucketName := parts[0]

	u, err := url.Parse("https://" + host)
	if err != nil {
		return nil, err
	}
	client := cos.NewClient(&cos.BaseURL{BucketURL: u}, &http.Client{
		Transport: &cos.AuthorizationTransport{
			SecretID:  accessKey,
			SecretKey: accessSecret,
		},
	})
	return &storageCos{
		client:       client,
		host:         host,
		accessKey:    accessKey,
		accessSecret: accessSecret,
		bucket:       bucketName,
	}, nil
}

// PresignedPutObject implements ObjectStorage
func (c *storageCos) PresignedPutObject(ctx context.Context, objectName string, expires time.Duration) (u *url.URL, err error) {
	return c.client.Object.GetPresignedURL(ctx, "PUT", objectName, c.accessKey, c.accessSecret, expires, nil)
}

// PresignedGetObject implements ObjectStorage
func (c *storageCos) PresignedGetObject(ctx context.Context, objectName string, expires time.Duration) (u *url.URL, err error) {
	return c.client.Object.GetPresignedURL(ctx, "GET", objectName, c.accessKey, c.accessSecret, expires, nil)
}

// MoveObject implements ObjectStorage
func (c *storageCos) MoveObject(ctx context.Context, src string, dst string) error {
	srcURL := fmt.Sprintf("%s/%s", c.host, src)

	if _, _, err := c.client.Object.Copy(ctx, dst, srcURL, nil); err != nil {
		return fmt.Errorf("copy object failed while move object: %w", err)
	}
	if _, err := c.client.Object.Delete(ctx, src, nil); err != nil {
		return fmt.Errorf("delete object failed while move object: %w", err)
	}
	return nil
}

// ObjectExists implements ObjectStorage
func (c *storageCos) ObjectExists(ctx context.Context, objectName string) (bool, error) {
	return c.client.Object.IsExist(ctx, objectName)
}