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import os
import struct
from enum import Enum
class Flag(Enum):
DDB_IS_SUBTRACK = 1 << 0 # file is not single-track, might have metainfo in external file
DDB_IS_READONLY = 1 << 1 # check this flag to block tag writing (e.g. in iso.wv)
DDB_HAS_EMBEDDED_CUESHEET = 1 << 2
DDB_TAG_ID3V1 = 1 << 8
DDB_TAG_ID3V22 = 1 << 9
DDB_TAG_ID3V23 = 1 << 10
DDB_TAG_ID3V24 = 1 << 11
DDB_TAG_APEV2 = 1 << 12
DDB_TAG_VORBISCOMMENTS = 1 << 13
DDB_TAG_CUESHEET = 1 << 14
DDB_TAG_ICY = 1 << 15
DDB_TAG_ITUNES = 1 << 16
DDB_TAG_MASK = 0x000fff00
class Track:
def __init__(self):
self.uri = None
self.decoder = None
self.num = None
self.startsample = None
self.endsample = None
self.duration = None
self.filetype = None
self.replaygain_albumgain = None
self.replaygain_albumpeak = None
self.replaygain_trackgain = None
self.replaygain_trackpeak = None
self.flags = 0
self.meta = {}
class Playlist:
def __init__(self):
self.major_version = None
self.minor_version = None
self.tracks_count = None
self.tracks = []
self.meta = {}
def read(file):
playlist = Playlist()
with open(file, 'rb') as f:
magic = f.read(4)
if magic != b'DBPL':
raise ValueError('invalid magic value')
# uint8_t
playlist.major_version, playlist.minor_version = struct.unpack('BB', f.read(2))
if playlist.major_version != 1:
raise ValueError('invalid major version')
if playlist.minor_version < 1:
raise ValueError('invalid minor version')
# uint32_t
tracks_count = struct.unpack('I', f.read(4))[0]
for i in range(tracks_count):
track = Track()
if playlist.minor_version <= 2:
# uint16_t
uri_len = struct.unpack('H', f.read(2))[0]
track.uri = f.read(uri_len)
# uint8_t
decoder_len = struct.unpack('B', f.read(1))[0]
if decoder_len >= 20:
raise ValueError('invalid decoder length')
if decoder_len:
track.decoder = f.read(decoder_len)
# int16_t
track.num = struct.unpack('h', f.read(2))[0]
# int32_t
track.startsample, track.endsample = struct.unpack('ii', f.read(8))
# float
track.duration = struct.unpack('f', f.read(4))[0]
if playlist.minor_version <= 2:
# legacy filetype support, they say
# uint8_t
filetype_len = struct.unpack('B', f.read(1))[0]
if filetype_len:
track.filetype = f.read(filetype_len)
# floats
ag, ap, tg, tp = struct.unpack('ffff', f.read(16))
if ag != 0:
track.replaygain_albumgain = ag
if ap != 0 and ap != 1:
track.replaygain_albumpeak = ap
if tg != 0:
track.replaygain_trackgain = tg
if tp != 0 and tp != 1:
track.replaygain_trackpeak = tp
if playlist.minor_version >= 2:
# uint32_t
track.flags = struct.unpack('I', f.read(4))[0]
elif track.startsample > 0 or track.endsample > 0 or track.num > 0:
track.flags |= Flag.DDB_IS_SUBTRACK
# int16_t
nm = struct.unpack('h', f.read(2))[0]
for j in range(nm):
# uint16_t
value_len = struct.unpack('H', f.read(2))[0]
if value_len >= 20000:
raise ValueError('invalid key length')
key = f.read(value_len)
value_len = struct.unpack('H', f.read(2))[0]
if value_len >= 20000:
f.seek(value_len, os.SEEK_CUR)
else:
value = f.read(value_len)
if key[0] == ':':
value = int(value)
if key == ':STARTSAMPLE':
track.startsample = value
elif key == ':ENDSAMPLE':
track.endsample = value
else:
track.meta[key] = value
else:
track.meta[key] = value
playlist.tracks.append(track)
assert tracks_count == len(playlist.tracks)
# playlist metadata
# int16_t
nm = struct.unpack('H', f.read(2))[0]
for i in range(nm):
# int16_t
key_len = struct.unpack('h', f.read(2))[0]
if key_len < 0 or key_len >= 20000:
raise ValueError('invalid length')
key = f.read(key_len)
# int16_t
value_len = struct.unpack('h', f.read(2))[0]
if value_len < 0 or value_len >= 20000:
f.seek(value_len, os.SEEK_CUR)
else:
value = f.read(value_len)
playlist.meta[key] = value
return playlist
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