import asyncio
import json
import queue
import threading
from pathlib import Path
from typing import Callable

from database.connection import DatabasePool
import env
from database.migrations import DatabaseMigrator
from registry import create_input_service, create_output_service
from registry_bootstrap import bootstrap
from util.util import LOGGER, read_env, shutdown_hook


def main() -> None:
    if not env.DATA_DIR.exists():
        env.DATA_DIR.mkdir(parents=True)

    if not env.SETTINGS_DIR.exists():
        LOGGER.info("First launch detected! Creating %s and exiting!", env.SETTINGS_DIR)
        return

    migrator = DatabaseMigrator(env.DATABASE_DIR, env.MIGRATIONS_DIR)
    try:
        migrator.migrate()
    except Exception:
        LOGGER.exception("Failed to migrate database!")
        return
    finally:
        migrator.close()

    db_pool = DatabasePool(env.DATABASE_DIR)

    LOGGER.info("Bootstrapping registries...")
    bootstrap()

    LOGGER.info("Loading settings...")

    with open(env.SETTINGS_DIR) as f:
        settings = json.load(f)
        read_env(settings)

    if "input" not in settings:
        raise KeyError("No `input` sepcified in settings!")
    if "outputs" not in settings:
        raise KeyError("No `outputs` spicified in settings!")

    input = create_input_service(db_pool, settings["input"])
    outputs = [create_output_service(db_pool, data) for data in settings["outputs"]]

    LOGGER.info("Starting task worker...")

    def worker(task_queue: queue.Queue[Callable[[], None] | None]):
        while True:
            task = task_queue.get()
            if task is None:
                break

            try:
                task()
            except Exception:
                LOGGER.exception("Exception in worker thread!")
            finally:
                task_queue.task_done()

    task_queue: queue.Queue[Callable[[], None] | None] = queue.Queue()
    thread = threading.Thread(target=worker, args=(task_queue,), daemon=True)
    thread.start()

    LOGGER.info("Connecting to %s...", input.url)
    input.outputs = outputs
    input.submitter = lambda c: task_queue.put(c)
    try:
        asyncio.run(input.listen())
    except KeyboardInterrupt:
        LOGGER.info("Stopping...")

    task_queue.join()
    task_queue.put(None)
    thread.join()
    db_pool.close()

    for shook in shutdown_hook:
        shook()


if __name__ == "__main__":
    main()