Slightly reorganise the project structure

telethon/utils.py

@@ -0,0 +1,99 @@
+"""
+Utilities for working with the Telegram API itself (such as handy methods
+to convert between an entity like an User, Chat, etc. into its Input version)
+"""
+from mimetypes import add_type, guess_extension
+
+from .tl.types import (
+    Channel, Chat, ChatPhoto, InputPeerChannel, InputPeerChat, InputPeerUser,
+    MessageMediaDocument, MessageMediaPhoto, PeerChannel, PeerChat, PeerUser,
+    User, UserProfilePhoto)
+
+
+def get_display_name(entity):
+    """Gets the input peer for the given "entity" (user, chat or channel)
+       Returns None if it was not found"""
+    if isinstance(entity, User):
+        if entity.last_name is not None:
+            return '{} {}'.format(entity.first_name, entity.last_name)
+        return entity.first_name
+
+    if isinstance(entity, Chat) or isinstance(entity, Channel):
+        return entity.title
+
+    return '(unknown)'
+
+# For some reason, .webp (stickers' format) is not registered
+add_type('image/webp', '.webp')
+
+
+def get_extension(media):
+    """Gets the corresponding extension for any Telegram media"""
+
+    # Photos are always compressed as .jpg by Telegram
+    if (isinstance(media, UserProfilePhoto) or isinstance(media, ChatPhoto) or
+            isinstance(media, MessageMediaPhoto)):
+        return '.jpg'
+
+    # Documents will come with a mime type, from which we can guess their mime type
+    if isinstance(media, MessageMediaDocument):
+        extension = guess_extension(media.document.mime_type)
+        return extension if extension else ''
+
+    return None
+
+
+def get_input_peer(entity):
+    """Gets the input peer for the given "entity" (user, chat or channel).
+       A ValueError is raised if the given entity isn't a supported type."""
+    if (isinstance(entity, InputPeerUser) or
+        isinstance(entity, InputPeerChat) or
+            isinstance(entity, InputPeerChannel)):
+        return entity
+
+    if isinstance(entity, User):
+        return InputPeerUser(entity.id, entity.access_hash)
+    if isinstance(entity, Chat):
+        return InputPeerChat(entity.id)
+    if isinstance(entity, Channel):
+        return InputPeerChannel(entity.id, entity.access_hash)
+
+    raise ValueError('Cannot cast {} to any kind of InputPeer.'
+                     .format(type(entity).__name__))
+
+
+def find_user_or_chat(peer, users, chats):
+    """Finds the corresponding user or chat given a peer.
+       Returns None if it was not found"""
+    try:
+        if isinstance(peer, PeerUser):
+            user = next(u for u in users if u.id == peer.user_id)
+            return user
+
+        elif isinstance(peer, PeerChat):
+            chat = next(c for c in chats if c.id == peer.chat_id)
+            return chat
+
+        elif isinstance(peer, PeerChannel):
+            channel = next(c for c in chats if c.id == peer.channel_id)
+            return channel
+
+    except StopIteration:
+        return None
+
+
+def get_appropriated_part_size(file_size):
+    """Gets the appropriated part size when uploading or downloading files,
+       given an initial file size"""
+    if file_size <= 1048576:  # 1MB
+        return 32
+    if file_size <= 10485760:  # 10MB
+        return 64
+    if file_size <= 393216000:  # 375MB
+        return 128
+    if file_size <= 786432000:  # 750MB
+        return 256
+    if file_size <= 1572864000:  # 1500MB
+        return 512
+
+    raise ValueError('File size too large')