package storage

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

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

type UploadInstruction struct {
	Method    string            `json:"method"`
	URL       string            `json:"url"`
	Headers   map[string]string `json:"headers"`
	ExpiresAt time.Time         `json:"expires_at"`
}

func (c *Client) PresignPut(ctx context.Context, objectKey, contentType string) (UploadInstruction, error) {
	if strings.TrimSpace(objectKey) == "" {
		return UploadInstruction{}, fmt.Errorf("对象键不能为空")
	}
	if strings.TrimSpace(contentType) == "" {
		return UploadInstruction{}, fmt.Errorf("内容类型不能为空")
	}

	result, err := c.client.Presign(ctx, &oss.PutObjectRequest{
		Bucket:          oss.Ptr(c.bucket),
		Key:             oss.Ptr(objectKey),
		ContentType:     oss.Ptr(contentType),
		ForbidOverwrite: oss.Ptr("true"),
	}, oss.PresignExpires(c.presignTTL))
	if err != nil {
		return UploadInstruction{}, fmt.Errorf("生成上传预签名: %w", err)
	}

	return UploadInstruction{
		Method:    result.Method,
		URL:       result.URL,
		Headers:   result.SignedHeaders,
		ExpiresAt: result.Expiration,
	}, nil
}