"""Add data-access resource catalog labels.

Revision ID: 334
Revises: 333
Create Date: 2026-06-11

DAX-045 projects catalog feed labels into ``data_access_resources`` alongside
the existing owner/source/version/etag fields. Labels are source metadata for
request display and audit context; runtime owner authorization still reads
only ``owner_person_id`` plus ``owner_resolution_status`` from the row.
"""
from __future__ import annotations

import sqlalchemy as sa

from alembic import op

revision = "337"
down_revision = "336"
branch_labels = None
depends_on = None

TABLE = "data_access_resources"
COLUMN = "labels"


def _column_exists(bind, table: str, column: str) -> bool:
    return bool(bind.execute(
        sa.text(
            "SELECT 1 FROM information_schema.columns "
            "WHERE table_schema = DATABASE() "
            "AND table_name = :t AND column_name = :c LIMIT 1",
        ),
        {"t": table, "c": column},
    ).scalar())


def upgrade() -> None:
    bind = op.get_bind()
    if not _column_exists(bind, TABLE, COLUMN):
        op.add_column(TABLE, sa.Column(COLUMN, sa.JSON(), nullable=True))


def downgrade() -> None:
    bind = op.get_bind()
    if _column_exists(bind, TABLE, COLUMN):
        op.drop_column(TABLE, COLUMN)