import logging
import os
import threading
import time

from google.cloud import pubsub_v1


script_dir = os.path.dirname(os.path.realpath(__file__))
log_filename = os.path.join(script_dir, "subscriber.log")

log_format = (
    "%(levelname)-8s [%(asctime)s] %(threadName)-33s "
    "[%(name)s] [%(filename)s:%(lineno)d][%(funcName)s] %(message)s"
)

logging.basicConfig(
    level=logging.DEBUG,
    format=log_format,
)

logger = logging.getLogger(__name__)

PROJECT_NAME = "my-project"
TOPIC_NAME = "my-events"
SUBSCRIPTION_NAME = f"subscription_{TOPIC_NAME}"


def main():
    subscriber = pubsub_v1.SubscriberClient()

    subscription_path = subscriber.subscription_path(PROJECT_NAME, SUBSCRIPTION_NAME)
    topic_path = subscriber.topic_path(PROJECT_NAME, TOPIC_NAME)
    # TODO: if topic does not exist, you must first create it
    subscriber.create_subscription(name=subscription_path, topic=topic_path)

    print("Starting a pull...")
    response = subscriber.pull(
        subscription_path, max_messages=3,
        # return_immediately=True
    )

    received_messages = response.received_messages

    if not received_messages:
        print("No messages received")
        return

    print("response >>", response)

    for message in response.received_messages:
        print(message.message.data.decode("utf-8"))
    
    print("Sending ACK...")
    subscriber.acknowledge(
        subscription_path, [msg.ack_id for msg in response.received_messages]
    )
    print("... ACK sent.")


if __name__ == "__main__":
    main()