"""Indexes the large-library read paths need (US07-06).

Revision ID: 0016_performance_indexes
Revises: 0015_exif_projections
Create Date: 2026-08-17

Measured, not guessed. At 100k assets the workflow home and the safety queue both
resolve "the current decision per asset" with a window function over
``safety_reviews``; a plain ``asset_id`` index makes SQLite sort every partition by
hand. Ordering the index by ``(asset_id, created_at DESC)`` halves that query.

``duplicate_members(cluster_id, asset_id)`` serves the paged member list of a
cluster with thousands of members, which is the other page that stopped being cheap.
"""

from alembic import op

revision = "0016_performance_indexes"
down_revision = "0015_exif_projections"
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.create_index(
        "ix_safety_reviews_asset_created",
        "safety_reviews",
        ["asset_id", "created_at"],
    )
    op.create_index(
        "ix_duplicate_members_cluster_asset",
        "duplicate_members",
        ["cluster_id", "asset_id"],
    )
    op.create_index(
        "ix_analysis_results_approx_year",
        "analysis_results",
        ["approx_year"],
    )


def downgrade() -> None:
    op.drop_index("ix_analysis_results_approx_year", table_name="analysis_results")
    op.drop_index("ix_duplicate_members_cluster_asset", table_name="duplicate_members")
    op.drop_index("ix_safety_reviews_asset_created", table_name="safety_reviews")