import asyncio
from logging.config import fileConfig

from sqlalchemy import pool
from sqlalchemy.engine import Connection
from sqlalchemy.ext.asyncio import async_engine_from_config

from alembic import context

# Load all models so Alembic can detect them for autogenerate
from src.database.load_models import load_all_models
load_all_models()

from src.database.base import Base
from src.core.config import settings

config = context.config

if config.config_file_name is not None:
    fileConfig(config.config_file_name)

# Set the database URL from settings (overrides alembic.ini)
db_url = settings.DATABASE_URL
if db_url.startswith("postgresql://"):
    db_url = db_url.replace("postgresql://", "postgresql+psycopg://", 1)
elif not db_url.startswith("postgresql+psycopg://"):
    db_url = "postgresql+psycopg://" + db_url.split("://", 1)[-1]

config.set_main_option("sqlalchemy.url", db_url.replace("%", "%%"))

target_metadata = Base.metadata


def run_migrations_offline() -> None:
    url = config.get_main_option("sqlalchemy.url")
    context.configure(
        url=url,
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
    )
    with context.begin_transaction():
        context.run_migrations()


def do_run_migrations(connection: Connection) -> None:
    context.configure(connection=connection, target_metadata=target_metadata)
    with context.begin_transaction():
        context.run_migrations()


async def run_async_migrations() -> None:
    connectable = async_engine_from_config(
        config.get_section(config.config_ini_section, {}),
        prefix="sqlalchemy.",
        poolclass=pool.NullPool,
    )
    async with connectable.connect() as connection:
        await connection.run_sync(do_run_migrations)
    await connectable.dispose()


def run_migrations_online() -> None:
    import sys
    import selectors
    if sys.platform == "win32":
        # psycopg3 async requires SelectorEventLoop on Windows (not default ProactorEventLoop)
        loop = asyncio.SelectorEventLoop(selectors.SelectSelector())
        asyncio.set_event_loop(loop)
        try:
            loop.run_until_complete(run_async_migrations())
        finally:
            loop.close()
    else:
        asyncio.run(run_async_migrations())


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()