"""MAX event to internal protocol converter."""
from typing import Union, List
from core.protocol import (
    IncomingMessage,
    IncomingCommand,
    IncomingCallback,
    Attachment,
)


def _extract_command(text: str) -> Union[IncomingCommand, IncomingCallback, None]:
    if not text.startswith("!"):
        return None

    parts = text.strip().split(maxsplit=1)
    cmd = parts[0].lower()
    args = parts[1] if len(parts) > 1 else ""

    if cmd == "!yes":
        return IncomingCallback(
            user_id="",
            platform="max",
            chat_id="",
            action="confirm",
        )
    elif cmd == "!no":
        return IncomingCallback(
            user_id="",
            platform="max",
            chat_id="",
            action="cancel",
        )
    else:
        return IncomingCommand(
            user_id="",
            platform="max",
            chat_id="",
            command=cmd.lstrip("!"),
            args=args.split() if args else [],
        )


def max_message_to_incoming(
    *,
    text: str,
    user_id: str,
    chat_id: str,
    attachments: List[Attachment] = None,
    callback_data: str = None,
    message_id: str = None,
) -> Union[IncomingMessage, IncomingCommand, IncomingCallback]:
    if callback_data:
        return IncomingCallback(
            user_id=user_id,
            platform="max",
            chat_id=chat_id,
            action=callback_data,
            payload={"message_id": message_id} if message_id else {},
        )

    if text:
        cmd = _extract_command(text)
        if cmd is not None:
            cmd.user_id = user_id
            cmd.chat_id = chat_id
            return cmd

    return IncomingMessage(
        user_id=user_id,
        platform="max",
        chat_id=chat_id,
        text=text or "",
        attachments=attachments or [],
    )


def max_attachment_to_internal(
    *,
    filename: str,
    mime_type: str,
    download_url: str,
) -> Attachment:
    return Attachment(
        type="document",
        url=download_url,
        filename=filename,
        mime_type=mime_type,
    )