"""Declarative base with a stable constraint-naming convention.

A fixed naming convention is important so Alembic generates deterministic,
human-readable names for indexes/constraints across migrations.
"""

from sqlalchemy import MetaData
from sqlalchemy.orm import DeclarativeBase

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",
}


class Base(DeclarativeBase):
    metadata = MetaData(naming_convention=NAMING_CONVENTION)