import argparse
import asyncio
import traceback

import asyncpg
import asyncpg_trek as pgtrek
import dotenv
from asyncpg_trek.asyncpg import AsyncpgBackend

env_cfg: dict[str, str | None] = {}


def parse_args():
    parser = argparse.ArgumentParser(
        description="Migrates the database from the current revision to a new specified one.",
    )
    parser.add_argument(
        "revision",
        default="NEWEST",
        help="the revision to upgrade/downgrade to. defaults to the newest one via the constant 'NEWEST'",
    )
    parser.add_argument(
        "-f",
        "--folder",
        default="migrations",
        help="the folder where migrations are stored",
    )
    parser.add_argument(
        "-e",
        "--env",
        default=".env",
        help="the .env file for the database. this is used to log into the database",
    )
    parser.add_argument(
        "--dry-run",
        action="store_true",
        help="whether to perform a dry run of this script",
    )
    parser.add_argument(
        "-d",
        "--direction",
        default="up",
        help="which direction the migration from the current to the specified goes in. defaults to up",
    )
    return parser.parse_args()


async def main(args: argparse.Namespace):
    if (db_url := env_cfg.get("DATABASE")) is None:
        raise RuntimeError()

    dir: pgtrek.Direction
    if args.direction.lower() == "down":
        dir = pgtrek.Direction.down
    else:
        dir = pgtrek.Direction.up

    conn = await asyncpg.connect(db_url)
    backend = AsyncpgBackend(conn)

    try:
        plans = await pgtrek.plan(
            backend,
            args.folder,
            target_revision=args.revision,
            direction=dir,
        )
        await pgtrek.execute(backend, plans)
    except Exception as e:
        print("oh nyo, something went wrong!")
        traceback.print_exception(e)
        return

    print("all done! :D")


if __name__ == "__main__":
    args = parse_args()
    env_cfg = dotenv.dotenv_values(args.env)
    asyncio.run(main(args))