package storage

import (
	"context"
	"fmt"
	"strings"
	"time"

	"github.com/aliyun/alibabacloud-oss-go-sdk-v2/oss"
)

type ObjectInfo struct {
	Size         int64
	ETag         string
	LastModified time.Time
}

func (c *Client) Stat(ctx context.Context, objectKey string) (ObjectInfo, error) {
	if strings.TrimSpace(objectKey) == "" {
		return ObjectInfo{}, fmt.Errorf("对象键不能为空")
	}

	result, err := c.client.GetObjectMeta(ctx, &oss.GetObjectMetaRequest{
		Bucket: oss.Ptr(c.bucket),
		Key:    oss.Ptr(objectKey),
	})
	if err != nil {
		return ObjectInfo{}, fmt.Errorf("查询对象元数据: %w", err)
	}
	if result == nil {
		return ObjectInfo{}, fmt.Errorf("对象元数据为空")
	}
	if result.ContentLength < 0 {
		return ObjectInfo{}, fmt.Errorf("对象大小无效: %d", result.ContentLength)
	}
	if result.ETag == nil {
		return ObjectInfo{}, fmt.Errorf("对象 ETag 缺失")
	}
	etag := strings.TrimSpace(strings.Trim(strings.TrimSpace(*result.ETag), "\""))
	if etag == "" {
		return ObjectInfo{}, fmt.Errorf("对象 ETag 无效")
	}
	if result.LastModified == nil || result.LastModified.IsZero() {
		return ObjectInfo{}, fmt.Errorf("对象最后修改时间缺失")
	}

	return ObjectInfo{
		Size:         result.ContentLength,
		ETag:         etag,
		LastModified: *result.LastModified,
	}, nil
}

func (c *Client) Delete(ctx context.Context, objectKey string) error {
	if strings.TrimSpace(objectKey) == "" {
		return fmt.Errorf("对象键不能为空")
	}

	_, err := c.client.DeleteObject(ctx, &oss.DeleteObjectRequest{
		Bucket: oss.Ptr(c.bucket),
		Key:    oss.Ptr(objectKey),
	})
	if err != nil {
		return fmt.Errorf("删除对象: %w", err)
	}

	return nil
}

func (c *Client) PublicURL(objectKey string) string {
	return strings.TrimRight(c.publicBaseURL, "/") + "/" + strings.TrimLeft(objectKey, "/")
}

func (c *Client) Bucket() string {
	return c.bucket
}