Authentication & Sessions

async def sign_in(
    self,
    phone: str = None,
    code: Union[str, int] = None,
    *,
    password: str = None,
    bot_token: str = None,
    phone_code_hash: str = None
) -> Union[types.User, types.auth.SentCode]:
    """
    Sign in to Telegram with phone/code or bot token.
    
    Parameters:
    - phone: Phone number in international format
    - code: Verification code received via SMS/app
    - password: Password for two-factor authentication
    - bot_token: Bot token for bot authentication
    - phone_code_hash: Hash from send_code_request (auto-managed)
    
    Returns:
    User object if successful, SentCode if more steps needed
    
    Raises:
    - SessionPasswordNeededError: If 2FA password required
    - PhoneCodeInvalidError: If verification code is invalid
    - FloodWaitError: If rate limited
    """

async def sign_up(
    self,
    code: Union[str, int],
    first_name: str,
    last_name: str = '',
    *,
    phone: str = None,
    phone_code_hash: str = None
) -> types.User:
    """
    Register a new user account.
    
    Parameters:
    - code: Verification code received via SMS/app
    - first_name: User's first name (required)
    - last_name: User's last name (optional)
    - phone: Phone number (auto-managed if not provided)
    - phone_code_hash: Hash from send_code_request (auto-managed)
    
    Returns:
    User object of the newly created account
    
    Raises:
    - PhoneCodeInvalidError: If verification code is invalid
    - FirstnameInvalidError: If first name is invalid
    """

async def send_code_request(
    self,
    phone: str,
    *,
    force_sms: bool = False
) -> types.auth.SentCode:
    """
    Request verification code for phone number.
    
    Parameters:
    - phone: Phone number in international format (e.g., '+1234567890')
    - force_sms: Force SMS delivery instead of Telegram app
    
    Returns:
    SentCode object with code delivery information
    
    Raises:
    - PhoneNumberInvalidError: If phone number format is invalid
    - FloodWaitError: If too many requests made recently
    """

async def qr_login(self, ignored_ids: List[int] = None) -> custom.QRLogin:
    """
    Initialize QR code login process.
    
    Parameters:
    - ignored_ids: List of authorization IDs to ignore
    
    Returns:
    QRLogin object for managing the QR login process
    
    Usage:
    async with client.qr_login() as qr_login:
        print(qr_login.url)  # Display QR code for this URL
        await qr_login.wait()  # Wait for user to scan
    """

async def log_out(self) -> bool:
    """
    Log out the current user and terminate the session.
    
    Returns:
    bool: True if logout successful, False otherwise
    
    Note:
    This invalidates the current session and requires re-authentication
    """

async def edit_2fa(
    self,
    current_password: str = None,
    new_password: str = None,
    *,
    hint: str = '',
    email: str = None,
    email_code_callback: Callable[[int], str] = None
) -> bool:
    """
    Enable, disable, or modify two-factor authentication.
    
    Parameters:
    - current_password: Current 2FA password (if enabled)
    - new_password: New password to set (None to disable)
    - hint: Password hint for users
    - email: Recovery email address
    - email_code_callback: Callback to get email verification code
    
    Returns:
    bool: True if 2FA settings updated successfully
    
    Raises:
    - PasswordHashInvalidError: If current password is wrong
    - EmailUnconfirmedError: If email verification required
    """

class StringSession:
    """
    Session stored as a base64-encoded string.
    Useful for serverless environments or when persistence is handled elsewhere.
    """
    def __init__(self, session: str = None):
        """
        Initialize string session.
        
        Parameters:
        - session: Previously saved session string (None for new session)
        """
    
    def save(self) -> str:
        """
        Get the session as a string for storage.
        
        Returns:
        str: Base64-encoded session data
        """

class SQLiteSession:
    """
    Session stored in SQLite database (default).
    Provides persistent storage with caching for entities and files.
    """
    def __init__(self, session_id: str):
        """
        Initialize SQLite session.
        
        Parameters:
        - session_id: Session identifier (creates session_id.session file)
        """

class MemorySession:
    """
    Session stored in memory only.
    Lost when process ends, useful for temporary operations.
    """
    def __init__(self):
        """Initialize memory-only session."""

def clone(self, to_instance=None) -> Session:
    """
    Clone the current session.
    
    Parameters:
    - to_instance: Target session instance to clone to
    
    Returns:
    Session: Cloned session instance
    """

def save(self) -> None:
    """Save current session state to storage."""

def close(self) -> None:
    """Close and clean up session resources."""

def set_dc(self, dc_id: int, server_address: str, port: int) -> None:
    """
    Set datacenter information.
    
    Parameters:
    - dc_id: Datacenter ID (1-5)
    - server_address: Server IP address
    - port: Server port number
    """

import asyncio
from telethon import TelegramClient

async def authenticate_user():
    client = TelegramClient('user_session', api_id, api_hash)
    await client.connect()
    
    if not await client.is_user_authorized():
        # Request verification code
        phone = input('Enter your phone number: ')
        await client.send_code_request(phone)
        
        # Enter the code
        code = input('Enter the verification code: ')
        
        try:
            await client.sign_in(phone, code)
        except SessionPasswordNeededError:
            # 2FA is enabled
            password = input('Enter your 2FA password: ')
            await client.sign_in(password=password)
    
    print("Authentication successful!")
    await client.disconnect()

asyncio.run(authenticate_user())

async def authenticate_bot():
    client = TelegramClient('bot_session', api_id, api_hash)
    await client.connect()
    
    # Bot authentication is simpler
    bot_token = 'your_bot_token_here'
    await client.sign_in(bot_token=bot_token)
    
    print("Bot authenticated successfully!")
    
    # Verify it's a bot
    if await client.is_bot():
        me = await client.get_me()
        print(f"Bot username: @{me.username}")
    
    await client.disconnect()

import qrcode
from io import BytesIO

async def qr_login():
    client = TelegramClient('qr_session', api_id, api_hash)
    await client.connect()
    
    # Start QR login process
    async with client.qr_login() as qr_login:
        # Generate QR code
        qr = qrcode.QRCode()
        qr.add_data(qr_login.url)
        qr.make()
        
        # Display QR code (this is a simple text version)
        qr.print_ascii(invert=True)
        print(f"QR URL: {qr_login.url}")
        print("Scan this QR code with your Telegram app")
        
        # Wait for user to scan and authorize
        try:
            await qr_login.wait()
            print("QR login successful!")
        except TimeoutError:
            print("QR login timed out")
    
    await client.disconnect()

from telethon.sessions import StringSession

async def use_string_session():
    # Load from existing session string
    session_string = "your_saved_session_string_here"
    
    client = TelegramClient(
        StringSession(session_string), 
        api_id, 
        api_hash
    )
    
    await client.connect()
    
    # Use client normally
    me = await client.get_me()
    print(f"Connected as {me.first_name}")
    
    # Save session string for next time
    saved_session = client.session.save()
    print(f"Save this for next time: {saved_session}")
    
    await client.disconnect()

async def setup_2fa():
    client = TelegramClient('session', api_id, api_hash)
    await client.start()
    
    # Enable 2FA
    password = "my_secure_password"
    hint = "My favorite password"
    email = "recovery@example.com"
    
    def email_code_callback(length):
        return input(f'Enter the {length}-digit code sent to your email: ')
    
    success = await client.edit_2fa(
        new_password=password,
        hint=hint,
        email=email,
        email_code_callback=email_code_callback
    )
    
    if success:
        print("2FA enabled successfully!")
    
    await client.disconnect()

from typing import Union, List, Optional, Callable, Any
from telethon.tl import types
from telethon import custom

PhoneNumber = str  # International format, e.g., '+1234567890'
VerificationCode = Union[str, int]
Password = str
BotToken = str
EmailCallback = Callable[[int], str]