"""Add taxonomy path aliases for canonical merges (e.g. plymouth-espresso-maple → plymouth-espresso).

Revision ID: 0049_add_master_taxonomy_path_alias
Revises: 0048_add_master_taxonomy_hierarchy
"""

from __future__ import annotations

from alembic import op
import sqlalchemy as sa

revision = "0049_add_master_taxonomy_path_alias"
down_revision = "0048_add_master_taxonomy_hierarchy"
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.create_table(
        "master_taxonomy_path_alias",
        sa.Column("id", sa.Integer(), primary_key=True, autoincrement=True),
        sa.Column("alias_path_slug", sa.String(512), nullable=False),
        sa.Column("canonical_node_id", sa.Integer(), sa.ForeignKey("master_taxonomy_node.id"), nullable=False),
        sa.Column("notes", sa.Text(), nullable=True),
        sa.Column("created_at", sa.DateTime(timezone=True), nullable=False, server_default=sa.func.now()),
        sa.UniqueConstraint("alias_path_slug", name="uq_master_taxonomy_path_alias_slug"),
    )
    op.create_index(
        "ix_master_taxonomy_path_alias_canonical_node_id",
        "master_taxonomy_path_alias",
        ["canonical_node_id"],
    )


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