package user

import (
	"context"
	"crypto/rand"
	"encoding/hex"
	"encoding/json"
	"example.com/userService/internal/types"
	"fmt"
	"strings"
	"time"
)

func (s *Service) ExportUser(ctx context.Context, req *types.UserIDReq) (*types.ExportResp, error) {
	u, err := s.GetUser(ctx, req)
	if err != nil {
		return nil, err
	}
	payload, err := json.Marshal(u)
	if err != nil {
		return nil, s.failure(ctx, err)
	}
	var nonce [16]byte
	if _, err = rand.Read(nonce[:]); err != nil {
		return nil, s.failure(ctx, err)
	}
	key := fmt.Sprintf("exports/users/%d/%s.txt", u.ID, hex.EncodeToString(nonce[:]))
	if _, err = s.deps.Uploads.Put(ctx, key, strings.NewReader(string(payload)), int64(len(payload)), "text/plain"); err != nil {
		return nil, s.failure(ctx, err)
	}
	url, err := s.deps.Downloads.PresignGet(ctx, key, 5*time.Minute)
	if err != nil {
		cleanup, cancel := context.WithTimeout(context.WithoutCancel(ctx), 2*time.Second)
		defer cancel()
		_ = s.deps.Files.Delete(cleanup, key)
		return nil, s.failure(ctx, err)
	}
	s.deps.Logger.InfoContext(ctx, "user.exported", "userId", u.ID)
	return &types.ExportResp{DownloadURL: url.String()}, nil
}