"""add parent_route_id for route grouping

Revision ID: c3d4e5f6a7b8
Revises: b2c3d4e5f6a7
Create Date: 2026-02-06 12:00:00.000000

"""

from collections.abc import Sequence

import sqlalchemy as sa
from alembic import op

# revision identifiers, used by Alembic.
revision: str = "c3d4e5f6a7b8"
down_revision: str | Sequence[str] | None = "b2c3d4e5f6a7"
branch_labels: str | Sequence[str] | None = None
depends_on: str | Sequence[str] | None = None


def upgrade() -> None:
    op.add_column(
        "routes",
        sa.Column(
            "parent_route_id",
            sa.Integer(),
            sa.ForeignKey("routes.id", ondelete="CASCADE"),
            nullable=True,
            index=True,
        ),
    )


def downgrade() -> None:
    op.drop_column("routes", "parent_route_id")