utils.py

from typing import List

# Telegram message limit is 4096 characters
TELEGRAM_MAX_MESSAGE_LENGTH = 4096


def split_message(text: str, max_length: int = TELEGRAM_MAX_MESSAGE_LENGTH) -> List[str]:
    """
    Split a long message into chunks that fit within Telegram's message limit.
    Tries to split at paragraph boundaries when possible.
    """
    if len(text) <= max_length:
        return [text]

    chunks: List[str] = []
    remaining = text

    while len(remaining) > max_length:
        # Try to split at a double newline (paragraph break)
        split_pos = remaining.rfind("\n\n", 0, max_length)
        
        # If no paragraph break, try single newline
        if split_pos == -1:
            split_pos = remaining.rfind("\n", 0, max_length)
        
        # If no newline, split at word boundary
        if split_pos == -1:
            split_pos = remaining.rfind(" ", 0, max_length)
        
        # If no space, force split at max_length
        if split_pos == -1:
            split_pos = max_length

        chunk = remaining[:split_pos].strip()
        if chunk:
            chunks.append(chunk)
        remaining = remaining[split_pos:].strip()

    if remaining:
        chunks.append(remaining)

    return chunks