"""One-shot schema/role setup. Only this job receives database admin credentials."""
import os
from pathlib import Path
import psycopg
from psycopg import sql

def main():
    role = os.environ['APP_DB_USER']
    with psycopg.connect(os.environ['DATABASE_ADMIN_URL']) as c:
        admin, database = c.execute('SELECT current_user,current_database()').fetchone()
        if role == admin:
            raise RuntimeError('Application and database administrator must differ')
        if not c.execute('SELECT 1 FROM pg_roles WHERE rolname=%s', (role,)).fetchone():
            c.execute(sql.SQL('CREATE ROLE {} LOGIN').format(sql.Identifier(role)))
        c.execute(sql.SQL('ALTER ROLE {} NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION NOBYPASSRLS PASSWORD {}').format(
            sql.Identifier(role), sql.Literal(os.environ['APP_DB_PASSWORD'])))
        c.execute(Path(__file__).with_name('schema.sql').read_text())
        c.execute(sql.SQL('REVOKE CREATE ON SCHEMA public FROM PUBLIC'))
        c.execute(sql.SQL('GRANT CONNECT ON DATABASE {} TO {}').format(sql.Identifier(database),sql.Identifier(role)))
        c.execute(sql.SQL('GRANT USAGE ON SCHEMA dtf_local TO {}').format(sql.Identifier(role)))
        c.execute(sql.SQL('GRANT SELECT,INSERT,UPDATE,DELETE ON ALL TABLES IN SCHEMA dtf_local TO {}').format(sql.Identifier(role)))
        c.execute(sql.SQL('GRANT USAGE,SELECT ON ALL SEQUENCES IN SCHEMA dtf_local TO {}').format(sql.Identifier(role)))
    print('Local schema migrated; runtime role has DML only.')

if __name__ == '__main__': main()