from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

from pillar_tool.util import config

from os import lockf, F_LOCK
from os.path import dirname, realpath

from alembic.config import Config
from alembic.command import upgrade, check, util
from pillar_tool.util import config

def run_db_migrations():
    cfg = config()
    user = cfg.db.user
    password = cfg.db.password
    host = cfg.db.host
    port = cfg.db.port
    database = cfg.db.database
    alembic_cfg = Config()
    alembic_cfg.set_main_option('script_location', f'{dirname(realpath(__file__))}/migrations')
    alembic_cfg.set_main_option('sqlalchemy.url', f'postgresql://{user}:{password}@{host}:{port}/{database}')
    alembic_cfg.set_main_option('prepend_sys_path', '.')

    with open(realpath(__file__), 'a') as f:
        lockf(f.fileno(), F_LOCK, 0)
        upgrade(config=alembic_cfg, revision='head')



cfg = config()
SessionLocal = sessionmaker(
    autocommit=False,
    autoflush=False,
    bind=create_engine(
        url=f"postgresql+psycopg2://{cfg.db.user}:{cfg.db.password}@{cfg.db.host}:{cfg.db.port}/{cfg.db.database}"
    )
)

def get_connection():
    return SessionLocal()