"""stations.vision_worker_url e vision_results.worker_url (#45)

stations.vision_worker_url: worker di visione della stazione (NULL = centrale).
vision_results.worker_url: worker effettivamente chiamato per quel risultato.

Revision ID: 019_station_vision_worker
Revises: 018_task_loop_results
Create Date: 2026-10-11

"""
from typing import Sequence, Union

from alembic import op
import sqlalchemy as sa

revision: str = '019_station_vision_worker'
down_revision: Union[str, None] = '018_task_loop_results'
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


def upgrade() -> None:
    # batch_alter_table come nelle migrazioni vicine: serve a SQLite
    with op.batch_alter_table('stations') as batch:
        batch.add_column(sa.Column('vision_worker_url', sa.String(500), nullable=True))
    with op.batch_alter_table('vision_results') as batch:
        batch.add_column(sa.Column('worker_url', sa.String(500), nullable=True))


def downgrade() -> None:
    with op.batch_alter_table('vision_results') as batch:
        batch.drop_column('worker_url')
    with op.batch_alter_table('stations') as batch:
        batch.drop_column('vision_worker_url')