# pylint: disable=line-too-long
# pylint: disable=unused-argument
# pylint: disable=redefined-outer-name

import pytest
from helpers.cluster import ClickHouseCluster

cluster = ClickHouseCluster(__file__)
node = cluster.add_instance('node_default', stay_alive=True)

@pytest.fixture(scope='module', autouse=True)
def start_cluster():
    try:
        cluster.start()
        yield cluster
    finally:
        cluster.shutdown()


def test_system_logs_recreate():
    system_logs = [
        # enabled by default
        'query_log',
        'query_thread_log',
        'part_log',
        'trace_log',
        'metric_log',
    ]

    node.query('SYSTEM FLUSH LOGS')
    for table in system_logs:
        assert 'ENGINE = MergeTree' in node.query(f'SHOW CREATE TABLE system.{table}')
        assert 'ENGINE = Null' not in node.query(f'SHOW CREATE TABLE system.{table}')
        assert len(node.query(f"SHOW TABLES FROM system LIKE '{table}%'").strip().split('\n')) == 1

    # NOTE: we use zzz- prefix to make it the last file,
    # so that it will be applied last.
    for table in system_logs:
        node.exec_in_container(['bash', '-c', f"""echo "
        <clickhouse>
            <{table}>
                 <engine>ENGINE = Null</engine>
                 <partition_by remove='remove'/>
            </{table}>
        </clickhouse>
        " > /etc/clickhouse-server/config.d/zzz-override-{table}.xml
        """])

    node.restart_clickhouse()
    node.query('SYSTEM FLUSH LOGS')
    for table in system_logs:
        assert 'ENGINE = MergeTree' not in node.query(f'SHOW CREATE TABLE system.{table}')
        assert 'ENGINE = Null' in node.query(f'SHOW CREATE TABLE system.{table}')
        assert len(node.query(f"SHOW TABLES FROM system LIKE '{table}%'").strip().split('\n')) == 2

    for table in system_logs:
        node.exec_in_container(['rm', f'/etc/clickhouse-server/config.d/zzz-override-{table}.xml'])

    node.restart_clickhouse()
    node.query('SYSTEM FLUSH LOGS')
    for table in system_logs:
        assert 'ENGINE = MergeTree' in node.query(f'SHOW CREATE TABLE system.{table}')
        assert 'ENGINE = Null' not in node.query(f'SHOW CREATE TABLE system.{table}')
        assert len(node.query(f"SHOW TABLES FROM system LIKE '{table}%'").strip().split('\n')) == 3

    node.query('SYSTEM FLUSH LOGS')
    # Ensure that there was no superfluous RENAME's
    # IOW that the table created only when the structure is indeed different.
    for table in system_logs:
        assert len(node.query(f"SHOW TABLES FROM system LIKE '{table}%'").strip().split('\n')) == 3