package mount

import (
	"fmt"
	"io"

	"github.com/seaweedfs/seaweedfs/weed/filer"
	"github.com/seaweedfs/seaweedfs/weed/glog"
	"github.com/seaweedfs/seaweedfs/weed/operation"
	"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
	"github.com/seaweedfs/seaweedfs/weed/security"
	"github.com/seaweedfs/seaweedfs/weed/util"
)

func (wfs *WFS) saveDataAsChunk(fullPath util.FullPath) filer.SaveDataAsChunkFunctionType {

	return func(reader io.Reader, filename string, offset int64, tsNs int64) (chunk *filer_pb.FileChunk, err error) {
		uploader, err := operation.NewUploader()
		if err != nil {
			return
		}

		uploadOption := &operation.UploadOption{
			Filename:          filename,
			Cipher:            wfs.option.Cipher,
			IsInputCompressed: false,
			MimeType:          "",
			PairMap:           nil,
		}
		genFileUrlFn := func(host, fileId string) string {
			fileUrl := fmt.Sprintf("http://%s/%s", host, fileId)
			if wfs.option.VolumeServerAccess == "filerProxy" {
				fileUrl = fmt.Sprintf("http://%s/?proxyChunkId=%s", wfs.getCurrentFiler(), fileId)
			}
			return fileUrl
		}

		var fileId string
		var uploadResult *operation.UploadResult
		var data []byte

		if wfs.fileIdPool != nil {
			// Use pre-allocated file ID from pool — avoids AssignVolume RPC.
			fileId, uploadResult, err, data = uploader.UploadWithAssignFunc(
				func() (string, string, security.EncodedJwt, error) {
					entry, getErr := wfs.fileIdPool.Get()
					if getErr != nil {
						return "", "", "", getErr
					}
					return entry.FileId, entry.Host, entry.Auth, nil
				},
				uploadOption, genFileUrlFn, reader,
			)
		} else {
			fileId, uploadResult, err, data = uploader.UploadWithRetry(
				wfs,
				&filer_pb.AssignVolumeRequest{
					Count:       1,
					Replication: wfs.option.Replication,
					Collection:  wfs.option.Collection,
					TtlSec:     wfs.option.TtlSec,
					DiskType:    string(wfs.option.DiskType),
					DataCenter:  wfs.option.DataCenter,
					Path:        string(fullPath),
				},
				uploadOption, genFileUrlFn, reader,
			)
		}

		if err != nil {
			glog.V(0).Infof("upload data %v: %v", filename, err)
			return nil, fmt.Errorf("upload data: %w", err)
		}
		if uploadResult.Error != "" {
			glog.V(0).Infof("upload failure %v: %v", filename, err)
			return nil, fmt.Errorf("upload result: %v", uploadResult.Error)
		}

		if offset == 0 {
			wfs.chunkCache.SetChunk(fileId, data)
		}

		chunk = uploadResult.ToPbFileChunk(fileId, offset, tsNs)
		return chunk, nil
	}
}