from funcy import first

from pyinfra.server.buffering.queue import stream_queue, Queue


class QueuedStreamFunction:
    def __init__(self, stream_function):
        """Combines a stream function with a queue.

        Args:
            stream_function: Needs to operate on iterables.
        """
        self.queue = Queue()
        self.stream_function = stream_function

    def push(self, item):
        self.queue.append(item)

    def pop(self):
        items = stream_queue(self.queue)
        return first(self.stream_function(items))