"""add_deleted_at_to_tasks

Revision ID: f3d499f5d0cf
Revises: g2b3c4d5e6f7
Create Date: 2025-12-14 12:17:25.176482

"""
from typing import Sequence, Union

from alembic import op
import sqlalchemy as sa


# revision identifiers, used by Alembic.
revision: str = 'f3d499f5d0cf'
down_revision: Union[str, None] = 'g2b3c4d5e6f7'
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


def upgrade() -> None:
    """Add deleted_at column for soft delete support."""
    op.add_column(
        'tool_ocr_tasks',
        sa.Column('deleted_at', sa.DateTime(), nullable=True,
                  comment='Soft delete timestamp - NULL means not deleted')
    )
    op.create_index('ix_tool_ocr_tasks_deleted_at', 'tool_ocr_tasks', ['deleted_at'])


def downgrade() -> None:
    """Remove deleted_at column."""
    op.drop_index('ix_tool_ocr_tasks_deleted_at', table_name='tool_ocr_tasks')
    op.drop_column('tool_ocr_tasks', 'deleted_at')