"""rule_moments — the moments of work a rule arrives at (milestone 458 step 3)

Revision ID: 0117
Revises: 0116
Create Date: 2026-10-05

A rule mounted on a moment is delivered whenever that moment happens, by
lookup rather than by score. The moment is a catalog name, validated by the
service; the catalog is code, so there is no table to key it to. Cascades
with the rule, like rule_systems beside it.
"""
import sqlalchemy as sa
from alembic import op

revision = "0117"
down_revision = "0116"
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.create_table(
        "rule_moments",
        sa.Column(
            "rule_id", sa.BigInteger(),
            sa.ForeignKey("rules.id", ondelete="CASCADE"), primary_key=True,
        ),
        sa.Column("moment", sa.Text(), primary_key=True),
        sa.Column("created_at", sa.DateTime(timezone=True), nullable=True),
    )
    # The delivery read (step 4) asks "which rules are on this moment?", the
    # opposite direction from the primary key.
    op.create_index("ix_rule_moments_moment", "rule_moments", ["moment"])


def downgrade() -> None:
    op.drop_index("ix_rule_moments_moment", table_name="rule_moments")
    op.drop_table("rule_moments")