package main

import (
    "flag"

    "github.com/chrislusf/seaweedfs/weed/glog"
    "github.com/chrislusf/seaweedfs/weed/storage"
    "github.com/chrislusf/seaweedfs/weed/storage/needle"
    "os"
    "path/filepath"

    "fmt"
)

var (
    volumePath       = flag.String("dir", "/tmp", "data directory to store files")
    volumeCollection = flag.String("collection", "", "the volume collection name")
    volumeId         = flag.Int("volumeId", -1, "a volume id. The volume should already exist in the dir. The volume index file should not exist.")
)

func Checksum(n* needle.Needle) string {
     return fmt.Sprintf("%s%x", n.Id, n.Cookie)
}

type VolumeFileScanner4SeeDat struct {
    version needle.Version
    block storage.SuperBlock

    dir    string
    hashes map[string]bool
    dat * os.File
}

func (scanner *VolumeFileScanner4SeeDat) VisitSuperBlock(superBlock storage.SuperBlock) error {
    scanner.version = superBlock.Version()
    scanner.block = superBlock
    return nil

}
func (scanner *VolumeFileScanner4SeeDat) ReadNeedleBody() bool {
    return true
}

func (scanner *VolumeFileScanner4SeeDat) VisitNeedle(n *needle.Needle, offset int64) error {

    if scanner.dat == nil {
	newDatFile, err := os.Create(filepath.Join(*volumePath, "dat_fixed"))
	if err != nil {
		glog.Fatalf("Write New Volume Data %v", err)
	}
	scanner.dat = newDatFile
	scanner.dat.Write(scanner.block.Bytes())
    }

    checksum := Checksum(n)

    if scanner.hashes[checksum] {
        glog.V(0).Infof("duplicate checksum:%s fid:%d,%s%x @ offset:%d", checksum, *volumeId, n.Id, n.Cookie, offset)
        return nil
    }
    scanner.hashes[checksum] = true

    _, s, _, e := n.Append(scanner.dat, scanner.version)
    fmt.Printf("size %d error %v\n", s, e)

    return nil
}

func main() {
    flag.Parse()

    vid := needle.VolumeId(*volumeId)

    outpath, _ := filepath.Abs(filepath.Dir(os.Args[0]))

    scanner := &VolumeFileScanner4SeeDat{
        dir:    filepath.Join(outpath, "out"),
        hashes: map[string]bool{},
    }

    if _, err := os.Stat(scanner.dir); err != nil {
        if err := os.MkdirAll(scanner.dir, os.ModePerm); err != nil {
            glog.Fatalf("could not create output dir : %s", err)
        }
    }

    err := storage.ScanVolumeFile(*volumePath, *volumeCollection, vid, storage.NeedleMapInMemory, scanner)
    if err != nil {
        glog.Fatalf("Reading Volume File [ERROR] %s\n", err)
    }

}