# scopes.core.actor

import asyncio
from collections.abc import Awaitable, Callable
from typing import Any, Optional

from scopes.util import keywords as k, Symbol

# keywords:
k('active full ok quit retired suspended')

type Behavior = Callable[[Any], Awaitable[Behavior | None]]

class Mailbox:

    def __init__(self, maxsize:int = 0, status: Symbol = k.active):
        self.queue: asyncio.Queue = asyncio.Queue(maxsize)
        self.status: Symbol = status

async def loop(q: asyncio.Queue, bhv: Behavior) -> None:
    while True:
        msg = await q.get()
        if msg is k.quit: 
            break
        bhv = await bhv(msg) or bhv
        q.task_done()

def create(bhv: Behavior, maxsize: int = 0) -> Mailbox:
    mb = Mailbox(maxsize)
    asyncio.create_task(loop(mb.queue, bhv))
    return mb

async def send(mb: Mailbox, msg: Any, no_wait: bool = False) -> Symbol:
    if mb.status is k.retired:
        return k.retired
    if no_wait and mb.queue.full():
        return k.full
    await mb.queue.put(msg)
    return k.ok