"""Add coupling_count to musehub_symbol_vitals.

Pre-computed at push time: the number of distinct symbols this symbol
co-changes with. Enables the symbol list page to show a coupling score
per row without any aggregation at request time.

Revision ID: 0032
Revises: 0031
"""
from __future__ import annotations

from alembic import op
import sqlalchemy as sa

revision = "0032"
down_revision = "0031"
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.add_column(
        "musehub_symbol_vitals",
        sa.Column("coupling_count", sa.Integer, nullable=False, server_default="0"),
    )


def downgrade() -> None:
    from sqlalchemy import text
    op.execute(text("ALTER TABLE IF EXISTS musehub_symbol_vitals DROP COLUMN IF EXISTS coupling_count"))