Totally refactored source files location

Now it *should* be easier to turn Telethon
into a pip package

telethon/network/mtproto_plain_sender.py

@@ -0,0 +1,49 @@
+import time
+import random
+from telethon.utils import BinaryWriter, BinaryReader
+
+
+class MtProtoPlainSender:
+    """MTProto Mobile Protocol plain sender (https://core.telegram.org/mtproto/description#unencrypted-messages)"""
+    def __init__(self, transport):
+        self._sequence = 0
+        self._time_offset = 0
+        self._last_msg_id = 0
+        self._transport = transport
+
+    def send(self, data):
+        """Sends a plain packet (auth_key_id = 0) containing the given message body (data)"""
+        with BinaryWriter() as writer:
+            writer.write_long(0)
+            writer.write_long(self.get_new_msg_id())
+            writer.write_int(len(data))
+            writer.write(data)
+
+            packet = writer.get_bytes()
+            self._transport.send(packet)
+
+    def receive(self):
+        """Receives a plain packet, returning the body of the response"""
+        seq, body = self._transport.receive()
+        with BinaryReader(body) as reader:
+            auth_key_id = reader.read_long()
+            msg_id = reader.read_long()
+            message_length = reader.read_int()
+
+            response = reader.read(message_length)
+            return response
+
+    def get_new_msg_id(self):
+        """Generates a new message ID based on the current time (in ms) since epoch"""
+        # See https://core.telegram.org/mtproto/description#message-identifier-msg-id
+        ms_time = int(time.time() * 1000)
+        new_msg_id = (((ms_time // 1000) << 32) |  # "must approximately equal unixtime*2^32"
+                      ((ms_time % 1000) << 22) |  # "approximate moment in time the message was created"
+                      random.randint(0, 524288) << 2)  # "message identifiers are divisible by 4"
+
+        # Ensure that we always return a message ID which is higher than the previous one
+        if self._last_msg_id >= new_msg_id:
+            new_msg_id = self._last_msg_id + 4
+
+        self._last_msg_id = new_msg_id
+        return new_msg_id