from sqlalchemy import MetaData
from sqlalchemy.orm import declarative_base

__all__ = [
    'metadata',
    'BaseModel',
]

# Define naming convention for constraints
_naming_convention = {
    "ix": 'ix_%(column_0_label)s',
    "uq": "uq_%(table_name)s_%(column_0_name)s",
    "ck": "ck_%(table_name)s_%(constraint_name)s",
    "fk": "fk_%(table_name)s_%(column_0_name)s_%(referred_table_name)s",
    "pk": "pk_%(table_name)s"
}

# Create metadata object for database schemas
metadata = MetaData(naming_convention=_naming_convention)

# Generate declarative base class for database models
BaseModel = declarative_base(name='BaseModel', metadata=metadata)