MTPyroger/pyrogram/file_id.py
2021-01-01 22:58:48 +01:00

479 lines
15 KiB
Python

# Pyrogram - Telegram MTProto API Client Library for Python
# Copyright (C) 2017-2021 Dan <https://github.com/delivrance>
#
# This file is part of Pyrogram.
#
# Pyrogram is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Pyrogram is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with Pyrogram. If not, see <http://www.gnu.org/licenses/>.
import base64
import logging
import struct
from enum import IntEnum
from io import BytesIO
from pyrogram.raw.core import Bytes, String
log = logging.getLogger(__name__)
def b64_encode(s: bytes) -> str:
"""Encode bytes into a URL-safe Base64 string without padding
Parameters:
s (``bytes``):
Bytes to encode
Returns:
``str``: The encoded bytes
"""
return base64.urlsafe_b64encode(s).decode().strip("=")
def b64_decode(s: str) -> bytes:
"""Decode a URL-safe Base64 string without padding to bytes
Parameters:
s (``str``):
String to decode
Returns:
``bytes``: The decoded string
"""
return base64.urlsafe_b64decode(s + "=" * (-len(s) % 4))
def rle_encode(s: bytes) -> bytes:
"""Zero-value RLE encoder
Parameters:
s (``bytes``):
Bytes to encode
Returns:
``bytes``: The encoded bytes
"""
r = b""
n = 0
for b in s:
if b == 0:
n += 1
else:
if n > 0:
r += bytes([0, n])
n = 0
r += bytes([b])
if n > 0:
r += bytes([0, n])
return r
def rle_decode(s: bytes) -> bytes:
"""Zero-value RLE decoder
Parameters:
s (``bytes``):
Bytes to encode
Returns:
``bytes``: The encoded bytes
"""
r = b""
i = 0
while i < len(s):
if s[i] != 0:
r += bytes([s[i]])
else:
r += b"\x00" * s[i + 1]
i += 1
i += 1
return r
class FileType(IntEnum):
"""Known file types"""
THUMBNAIL = 0
CHAT_PHOTO = 1 # ProfilePhoto
PHOTO = 2
VOICE = 3 # VoiceNote
VIDEO = 4
DOCUMENT = 5
ENCRYPTED = 6
TEMP = 7
STICKER = 8
AUDIO = 9
ANIMATION = 10
ENCRYPTED_THUMBNAIL = 11
WALLPAPER = 12
VIDEO_NOTE = 13
SECURE_RAW = 14
SECURE = 15
BACKGROUND = 16
DOCUMENT_AS_FILE = 17
class ThumbnailSource(IntEnum):
"""Known thumbnail sources"""
LEGACY = 0
THUMBNAIL = 1
CHAT_PHOTO_SMALL = 2 # DialogPhotoSmall
CHAT_PHOTO_BIG = 3 # DialogPhotoBig
STICKER_SET_THUMBNAIL = 4
# Photo-like file ids are longer and contain extra info, the rest are all documents
PHOTO_TYPES = {FileType.THUMBNAIL, FileType.CHAT_PHOTO, FileType.PHOTO, FileType.WALLPAPER,
FileType.ENCRYPTED_THUMBNAIL}
DOCUMENT_TYPES = set(FileType) - PHOTO_TYPES
# Since the file type values are small enough to fit them in few bits, Telegram thought it would be a good idea to
# encode extra information about web url and file reference existence as flag inside the 4 bytes allocated for the field
WEB_LOCATION_FLAG = 1 << 24
FILE_REFERENCE_FLAG = 1 << 25
class FileId:
MAJOR = 4
MINOR = 30
def __init__(
self, *,
major: int = MAJOR,
minor: int = MINOR,
file_type: FileType,
dc_id: int,
file_reference: bytes = b"",
url: str = None,
media_id: int = None,
access_hash: int = None,
volume_id: int = None,
thumbnail_source: ThumbnailSource = None,
thumbnail_file_type: FileType = None,
thumbnail_size: str = "",
secret: int = None,
local_id: int = None,
chat_id: int = None,
chat_access_hash: int = None,
sticker_set_id: int = None,
sticker_set_access_hash: int = None
):
self.major = major
self.minor = minor
self.file_type = file_type
self.dc_id = dc_id
self.file_reference = file_reference
self.url = url
self.media_id = media_id
self.access_hash = access_hash
self.volume_id = volume_id
self.thumbnail_source = thumbnail_source
self.thumbnail_file_type = thumbnail_file_type
self.thumbnail_size = thumbnail_size
self.secret = secret
self.local_id = local_id
self.chat_id = chat_id
self.chat_access_hash = chat_access_hash
self.sticker_set_id = sticker_set_id
self.sticker_set_access_hash = sticker_set_access_hash
@staticmethod
def decode(file_id: str):
decoded = rle_decode(b64_decode(file_id))
# region read version
# File id versioning. Major versions lower than 4 don't have a minor version
major = decoded[-1]
if major < 4:
minor = 0
buffer = BytesIO(decoded[:-1])
else:
minor = decoded[-2]
buffer = BytesIO(decoded[:-2])
# endregion
file_type, dc_id = struct.unpack("<ii", buffer.read(8))
# region media type flags
# Check for flags existence
has_web_location = bool(file_type & WEB_LOCATION_FLAG)
has_file_reference = bool(file_type & FILE_REFERENCE_FLAG)
# Remove flags to restore the actual type id value
file_type &= ~WEB_LOCATION_FLAG
file_type &= ~FILE_REFERENCE_FLAG
# endregion
try:
file_type = FileType(file_type)
except ValueError:
raise ValueError(f"Unknown file_type {file_type} of file_id {file_id}")
if has_web_location:
url = String.read(buffer)
access_hash, = struct.unpack("<q", buffer.read(8))
return FileId(
major=major,
minor=minor,
file_type=file_type,
dc_id=dc_id,
url=url,
access_hash=access_hash
)
file_reference = Bytes.read(buffer) if has_file_reference else b""
media_id, access_hash = struct.unpack("<qq", buffer.read(16))
if file_type in PHOTO_TYPES:
volume_id, = struct.unpack("<q", buffer.read(8))
thumbnail_source, = (0,) if major < 4 else struct.unpack("<i", buffer.read(4))
try:
thumbnail_source = ThumbnailSource(thumbnail_source)
except ValueError:
raise ValueError(f"Unknown thumbnail_source {thumbnail_source} of file_id {file_id}")
if thumbnail_source == ThumbnailSource.LEGACY:
secret, local_id = struct.unpack("<qi", buffer.read(12))
return FileId(
major=major,
minor=minor,
file_type=file_type,
dc_id=dc_id,
file_reference=file_reference,
media_id=media_id,
access_hash=access_hash,
volume_id=volume_id,
thumbnail_source=thumbnail_source,
secret=secret,
local_id=local_id
)
if thumbnail_source == ThumbnailSource.THUMBNAIL:
thumbnail_file_type, thumbnail_size, local_id = struct.unpack("<iii", buffer.read(12))
thumbnail_size = chr(thumbnail_size)
return FileId(
major=major,
minor=minor,
file_type=file_type,
dc_id=dc_id,
file_reference=file_reference,
media_id=media_id,
access_hash=access_hash,
volume_id=volume_id,
thumbnail_source=thumbnail_source,
thumbnail_file_type=thumbnail_file_type,
thumbnail_size=thumbnail_size,
local_id=local_id
)
if thumbnail_source in (ThumbnailSource.CHAT_PHOTO_SMALL, ThumbnailSource.CHAT_PHOTO_BIG):
chat_id, chat_access_hash, local_id = struct.unpack("<qqi", buffer.read(20))
return FileId(
major=major,
minor=minor,
file_type=file_type,
dc_id=dc_id,
file_reference=file_reference,
media_id=media_id,
access_hash=access_hash,
volume_id=volume_id,
thumbnail_source=thumbnail_source,
chat_id=chat_id,
chat_access_hash=chat_access_hash,
local_id=local_id
)
if thumbnail_source == ThumbnailSource.STICKER_SET_THUMBNAIL:
sticker_set_id, sticker_set_access_hash, local_id = struct.unpack("<qqi", buffer.read(20))
return FileId(
major=major,
minor=minor,
file_type=file_type,
dc_id=dc_id,
file_reference=file_reference,
media_id=media_id,
access_hash=access_hash,
volume_id=volume_id,
thumbnail_source=thumbnail_source,
sticker_set_id=sticker_set_id,
sticker_set_access_hash=sticker_set_access_hash,
local_id=local_id
)
if file_type in DOCUMENT_TYPES:
return FileId(
major=major,
minor=minor,
file_type=file_type,
dc_id=dc_id,
file_reference=file_reference,
media_id=media_id,
access_hash=access_hash
)
def encode(self, *, major: int = None, minor: int = None):
major = major if major is not None else self.major
minor = minor if minor is not None else self.minor
buffer = BytesIO()
file_type = self.file_type
if self.url:
file_type |= WEB_LOCATION_FLAG
if self.file_reference:
file_type |= FILE_REFERENCE_FLAG
buffer.write(struct.pack("<ii", file_type, self.dc_id))
if self.url:
buffer.write(String(self.url))
if self.file_reference:
buffer.write(Bytes(self.file_reference))
buffer.write(struct.pack("<qq", self.media_id, self.access_hash))
if self.file_type in PHOTO_TYPES:
buffer.write(struct.pack("<q", self.volume_id))
if major >= 4:
buffer.write(struct.pack("<i", self.thumbnail_source))
if self.thumbnail_source == ThumbnailSource.LEGACY:
buffer.write(struct.pack("<qi", self.secret, self.local_id))
elif self.thumbnail_source == ThumbnailSource.THUMBNAIL:
buffer.write(struct.pack(
"<iii",
self.thumbnail_file_type,
ord(self.thumbnail_size),
self.local_id
))
elif self.thumbnail_source in (ThumbnailSource.CHAT_PHOTO_SMALL, ThumbnailSource.CHAT_PHOTO_BIG):
buffer.write(struct.pack(
"<qqi",
self.chat_id,
self.chat_access_hash,
self.local_id
))
elif self.thumbnail_source == ThumbnailSource.STICKER_SET_THUMBNAIL:
buffer.write(struct.pack(
"<qqi",
self.sticker_set_id,
self.sticker_set_access_hash,
self.local_id
))
elif file_type in DOCUMENT_TYPES:
buffer.write(struct.pack("<ii", minor, major))
buffer.write(struct.pack("<bb", minor, major))
return b64_encode(rle_encode(buffer.getvalue()))
def __str__(self):
return str({k: v for k, v in self.__dict__.items() if v is not None})
class FileUniqueType(IntEnum):
"""Known file unique types"""
WEB = 0
PHOTO = 1
DOCUMENT = 2
SECURE = 3
ENCRYPTED = 4
TEMP = 5
class FileUniqueId:
def __init__(
self, *,
file_unique_type: FileUniqueType,
url: str = None,
media_id: int = None,
volume_id: int = None,
local_id: int = None
):
self.file_unique_type = file_unique_type
self.url = url
self.media_id = media_id
self.volume_id = volume_id
self.local_id = local_id
@staticmethod
def decode(file_unique_id: str):
buffer = BytesIO(rle_decode(b64_decode(file_unique_id)))
file_unique_type, = struct.unpack("<i", buffer.read(4))
try:
file_unique_type = FileUniqueType(file_unique_type)
except ValueError:
raise ValueError(f"Unknown file_unique_type {file_unique_type} of file_unique_id {file_unique_id}")
if file_unique_type == FileUniqueType.WEB:
url = String.read(buffer)
return FileUniqueId(
file_unique_type=file_unique_type,
url=url
)
if file_unique_type == FileUniqueType.PHOTO:
volume_id, local_id = struct.unpack("<qi", buffer.read())
return FileUniqueId(
file_unique_type=file_unique_type,
volume_id=volume_id,
local_id=local_id
)
if file_unique_type == FileUniqueType.DOCUMENT:
media_id, = struct.unpack("<q", buffer.read())
return FileUniqueId(
file_unique_type=file_unique_type,
media_id=media_id
)
# TODO: Missing decoder for SECURE, ENCRYPTED and TEMP
raise ValueError(f"Unknown decoder for file_unique_type {file_unique_type} of file_unique_id {file_unique_id}")
def encode(self):
if self.file_unique_type == FileUniqueType.WEB:
string = struct.pack("<is", self.file_unique_type, String(self.url))
elif self.file_unique_type == FileUniqueType.PHOTO:
string = struct.pack("<iqi", self.file_unique_type, self.volume_id, self.local_id)
elif self.file_unique_type == FileUniqueType.DOCUMENT:
string = struct.pack("<iq", self.file_unique_type, self.media_id)
else:
# TODO: Missing encoder for SECURE, ENCRYPTED and TEMP
raise ValueError(f"Unknown encoder for file_unique_type {self.file_unique_type}")
return b64_encode(rle_encode(string))
def __str__(self):
return str({k: v for k, v in self.__dict__.items() if v is not None})