package logic

import (
	"context"
	"time"

	"git.cialloo.com/CiallooWeb/Blog/app/internal/svc"
	"git.cialloo.com/CiallooWeb/Blog/app/internal/types"

	"github.com/aws/aws-sdk-go-v2/service/s3"
	"github.com/zeromicro/go-zero/core/logx"
)

type DownloadPresignedURLLogic struct {
	logx.Logger
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

// Get presigned URL for file download
func NewDownloadPresignedURLLogic(ctx context.Context, svcCtx *svc.ServiceContext) *DownloadPresignedURLLogic {
	return &DownloadPresignedURLLogic{
		Logger: logx.WithContext(ctx),
		ctx:    ctx,
		svcCtx: svcCtx,
	}
}

func (l *DownloadPresignedURLLogic) DownloadPresignedURL(req *types.DownloadPresignedURLReq) (resp *types.DownloadPresignedURLResp, err error) {
	// Calculate expiration time
	expiration := time.Duration(l.svcCtx.Config.S3.PresignedURLExpiration) * time.Second
	expireAt := time.Now().Add(expiration).Unix()

	// Create presigned client
	presignClient := s3.NewPresignClient(l.svcCtx.S3Client)

	// Generate presigned GET URL
	getObjectInput := &s3.GetObjectInput{
		Bucket: &l.svcCtx.Config.S3.Bucket,
		Key:    &req.File_key,
	}

	presignedReq, err := presignClient.PresignGetObject(l.ctx, getObjectInput, func(opts *s3.PresignOptions) {
		opts.Expires = expiration
	})
	if err != nil {
		l.Errorf("Failed to generate presigned URL: %v", err)
		return nil, err
	}

	return &types.DownloadPresignedURLResp{
		Url:       presignedReq.URL,
		Expire_at: expireAt,
	}, nil
}