"""IDENT-005: Hersteller/Modell-Stammdaten, geraet_instanz.modell_id.

Revision ID: 0030_hersteller_modell
Revises: 0029_dokument_original
Create Date: 2026-09-08
"""
from typing import Sequence, Union

from alembic import op

revision: str = "0030_hersteller_modell"
down_revision: Union[str, None] = "0029_dokument_original"
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


def upgrade() -> None:
    op.execute(
        """
        CREATE TABLE hersteller (
            id SERIAL PRIMARY KEY,
            name TEXT NOT NULL UNIQUE
        )
        """
    )
    op.execute(
        """
        CREATE TABLE modell (
            id SERIAL PRIMARY KEY,
            hersteller_id INTEGER NOT NULL REFERENCES hersteller(id),
            name TEXT NOT NULL,
            UNIQUE (hersteller_id, name)
        )
        """
    )
    op.execute("CREATE INDEX ix_modell_hersteller_id ON modell (hersteller_id)")
    op.execute("ALTER TABLE geraet_instanz ADD COLUMN modell_id INTEGER REFERENCES modell(id)")
    op.execute("CREATE INDEX ix_geraet_instanz_modell_id ON geraet_instanz (modell_id)")


def downgrade() -> None:
    op.execute("DROP INDEX IF EXISTS ix_geraet_instanz_modell_id")
    op.execute("ALTER TABLE geraet_instanz DROP COLUMN modell_id")
    op.execute("DROP INDEX IF EXISTS ix_modell_hersteller_id")
    op.execute("DROP TABLE modell")
    op.execute("DROP TABLE hersteller")