cli/algo/qmc/qmc.go
2020-12-26 16:07:48 +08:00

127 lines
3.4 KiB
Go

package qmc
import (
"encoding/base64"
"encoding/binary"
"errors"
"github.com/umlock-music/cli/algo/common"
)
var (
ErrQmcFileLength = errors.New("invalid qmc file length")
ErrQmcKeyDecodeFailed = errors.New("base64 decode qmc key failed")
ErrQmcKeyLength = errors.New("unexpected decoded qmc key length")
)
type Decoder struct {
file []byte
maskDetector func(encodedData []byte) (*Key256Mask, error)
mask *Key256Mask
audioExt string
key []byte
audio []byte
}
//goland:noinspection GoUnusedExportedFunction
func NewDefaultDecoder(data []byte) common.Decoder {
return &Decoder{file: data, mask: getDefaultMask()}
}
func NewMflac256Decoder(data []byte) common.Decoder {
return &Decoder{file: data, maskDetector: detectMflac256Mask, audioExt: "flac"}
}
func NewMgg256Decoder(data []byte) common.Decoder {
return &Decoder{file: data, maskDetector: detectMgg256Mask, audioExt: "ogg"}
}
func (d *Decoder) Validate() error {
if nil != d.mask {
return nil
}
if nil != d.maskDetector {
if err := d.validateKey(); err != nil {
return err
}
var err error
d.mask, err = d.maskDetector(d.file)
return err
}
return errors.New("no mask or mask detector found")
}
func (d *Decoder) validateKey() error {
lenData := len(d.file)
if lenData < 4 {
return ErrQmcFileLength
}
keyLen := binary.LittleEndian.Uint32(d.file[lenData-4:])
if lenData < int(keyLen+4) {
return ErrQmcFileLength
}
var err error
d.key, err = base64.StdEncoding.DecodeString(
string(d.file[lenData-4-int(keyLen) : lenData-4]))
if err != nil {
return ErrQmcKeyDecodeFailed
}
if len(d.key) != 272 {
return ErrQmcKeyLength
}
d.file = d.file[:lenData-4-int(keyLen)]
return nil
}
func (d *Decoder) Decode() error {
d.audio = d.mask.Decrypt(d.file)
return nil
}
func (d Decoder) GetCoverImage() []byte {
return nil
}
func (d Decoder) GetAudioData() []byte {
return d.audio
}
func (d Decoder) GetAudioExt() string {
return d.audioExt
}
func (d Decoder) GetMeta() common.Meta {
return nil
}
func DecoderFuncWithExt(ext string) common.NewDecoderFunc {
return func(file []byte) common.Decoder {
return &Decoder{file: file, audioExt: ext}
}
}
//goland:noinspection SpellCheckingInspection
func init() {
common.RegisterDecoder("qmc3", DecoderFuncWithExt("mp3")) //QQ Music Mp3
common.RegisterDecoder("qmc2", DecoderFuncWithExt("ogg")) //QQ Music Ogg
common.RegisterDecoder("qmc0", DecoderFuncWithExt("mp3")) //QQ Music Mp3
common.RegisterDecoder("qmcflac", DecoderFuncWithExt("flac")) //QQ Music Flac
common.RegisterDecoder("qmcogg", DecoderFuncWithExt("ogg")) //QQ Music Ogg
common.RegisterDecoder("tkm", DecoderFuncWithExt("m4a")) //QQ Music Accompaniment M4a
common.RegisterDecoder("bkcmp3", DecoderFuncWithExt("mp3")) //Moo Music Mp3
common.RegisterDecoder("bkcflac", DecoderFuncWithExt("flac")) //Moo Music Flac
common.RegisterDecoder("666c6163", DecoderFuncWithExt("flac")) //QQ Music Weiyun Flac
common.RegisterDecoder("6d7033", DecoderFuncWithExt("mp3")) //QQ Music Weiyun Mp3
common.RegisterDecoder("6f6767", DecoderFuncWithExt("ogg")) //QQ Music Weiyun Ogg
common.RegisterDecoder("6d3461", DecoderFuncWithExt("m4a")) //QQ Music Weiyun M4a
common.RegisterDecoder("776176", DecoderFuncWithExt("wav")) //QQ Music Weiyun Wav
common.RegisterDecoder("mgg", NewMgg256Decoder) //QQ Music Weiyun Wav
common.RegisterDecoder("mflac", NewMflac256Decoder) //QQ Music Weiyun Wav
}