"""add indexes on foreign-key columns

Indexes the FK columns that are commonly filtered/joined and are not already the left-most
column of an existing unique constraint (those are covered by the constraint's index). Names
match SQLModel's index=True default (ix_<table>_<column>) so the ORM and DB stay in sync.

Revision ID: a7b8c9d0e1f2
Revises: f6a7b8c9d0e1
Create Date: 2026-07-01 09:30:00.000000

"""
from typing import Sequence, Union

from alembic import op


revision: str = 'a7b8c9d0e1f2'
down_revision: Union[str, None] = 'f6a7b8c9d0e1'
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


# (index_name, table, column)
_INDEXES = [
    ('ix_users_primary_account_id', 'users', 'primary_account_id'),
    ('ix_holdings_entity_id', 'holdings', 'entity_id'),
    ('ix_positions_holding_id', 'positions', 'holding_id'),
    ('ix_valuation_rounds_submitted_by', 'valuation_rounds', 'submitted_by'),
    ('ix_valuation_rounds_approved_by', 'valuation_rounds', 'approved_by'),
    ('ix_valuations_position_id', 'valuations', 'position_id'),
    ('ix_audit_log_actor_user_id', 'audit_log', 'actor_user_id'),
    ('ix_entity_access_entity_id', 'entity_access', 'entity_id'),
    ('ix_documents_entity_id', 'documents', 'entity_id'),
    ('ix_documents_investor_user_id', 'documents', 'investor_user_id'),
    ('ix_documents_uploaded_by', 'documents', 'uploaded_by'),
    ('ix_capital_account_statements_investor_user_id',
     'capital_account_statements', 'investor_user_id'),
    ('ix_capital_account_statements_document_id',
     'capital_account_statements', 'document_id'),
]


def upgrade() -> None:
    for name, table, column in _INDEXES:
        op.create_index(name, table, [column])


def downgrade() -> None:
    for name, table, _column in reversed(_INDEXES):
        op.drop_index(name, table_name=table)