import pytest

from helpers.cluster import ClickHouseCluster
from helpers.test_tools import assert_eq_with_retry

cluster = ClickHouseCluster(__file__)

node1 = cluster.add_instance('node1', main_configs=["configs/config.d/remote_servers.xml"],
                             user_configs=["configs/users.d/allow_introspection_functions.xml"])
node2 = cluster.add_instance('node2', main_configs=["configs/config.d/remote_servers.xml"],
                             user_configs=["configs/users.d/allow_introspection_functions.xml"])
distributed = cluster.add_instance('distributed', main_configs=["configs/config.d/remote_servers.xml"],
                                   user_configs=["configs/users.d/allow_introspection_functions.xml"], stay_alive=True)


@pytest.fixture(scope="module", autouse=True)
def started_cluster():
    try:
        cluster.start()

        for node in [node1, node2]:
            node.query("CREATE TABLE sometable (date Date, id UInt32, value Int32) ENGINE = MergeTree() ORDER BY id;")
            node.query("INSERT INTO sometable VALUES (toDate('2010-01-10'), 1, 1)")
            node.query("CREATE USER shard")
            node.query("GRANT ALL ON *.* TO shard")

        distributed.query(
            "CREATE TABLE proxy (date Date, id UInt32, value Int32) ENGINE = Distributed(test_cluster, default, sometable, toUInt64(date));")
        distributed.query(
            "CREATE TABLE shard_settings (name String, value String) ENGINE = Distributed(test_cluster, system, settings);")
        distributed.query("CREATE ROLE admin")
        distributed.query("GRANT ALL ON *.* TO admin")

        yield cluster

    finally:
        cluster.shutdown()


@pytest.fixture(autouse=True)
def restart_distributed():
    # Magic: Distributed table tries to keep connections to shards open, and after changing shards' default settings
    # we need to reset connections to force the shards to reset sessions and therefore to reset current settings
    # to their new defaults.
    distributed.restart_clickhouse()


def test_select_clamps_settings():
    distributed.query("CREATE USER normal DEFAULT ROLE admin SETTINGS max_memory_usage = 80000000")
    distributed.query("CREATE USER wasteful DEFAULT ROLE admin SETTINGS max_memory_usage = 2000000000")
    distributed.query("CREATE USER readonly DEFAULT ROLE admin SETTINGS readonly = 1")
    node1.query("ALTER USER shard SETTINGS max_memory_usage = 50000000 MIN 11111111 MAX 99999999")
    node2.query("ALTER USER shard SETTINGS readonly = 1")

    # Check that shards doesn't throw exceptions on constraints violation
    query = "SELECT COUNT() FROM proxy"
    assert distributed.query(query) == '2\n'
    assert distributed.query(query, user='normal') == '2\n'
    assert distributed.query(query, user='wasteful') == '2\n'
    assert distributed.query(query, user='readonly') == '2\n'

    assert distributed.query(query, settings={"max_memory_usage": 40000000, "readonly": 2}) == '2\n'
    assert distributed.query(query, settings={"max_memory_usage": 3000000000, "readonly": 2}) == '2\n'

    query = "SELECT COUNT() FROM remote('node{1,2}', 'default', 'sometable')"
    assert distributed.query(query) == '2\n'
    assert distributed.query(query, user='normal') == '2\n'
    assert distributed.query(query, user='wasteful') == '2\n'

    # Check that shards clamp passed settings.
    query = "SELECT hostName() as host, name, value FROM shard_settings WHERE name = 'max_memory_usage' OR name = 'readonly' ORDER BY host, name, value"
    assert distributed.query(query) == 'node1\tmax_memory_usage\t99999999\n' \
                                       'node1\treadonly\t0\n' \
                                       'node2\tmax_memory_usage\t10000000000\n' \
                                       'node2\treadonly\t1\n'
    assert distributed.query(query, user='normal') == 'node1\tmax_memory_usage\t80000000\n' \
                                                      'node1\treadonly\t0\n' \
                                                      'node2\tmax_memory_usage\t10000000000\n' \
                                                      'node2\treadonly\t1\n'
    assert distributed.query(query, user='wasteful') == 'node1\tmax_memory_usage\t99999999\n' \
                                                        'node1\treadonly\t0\n' \
                                                        'node2\tmax_memory_usage\t10000000000\n' \
                                                        'node2\treadonly\t1\n'
    assert distributed.query(query, user='readonly') == 'node1\tmax_memory_usage\t99999999\n' \
                                                        'node1\treadonly\t1\n' \
                                                        'node2\tmax_memory_usage\t10000000000\n' \
                                                        'node2\treadonly\t1\n'

    assert distributed.query(query, settings={"max_memory_usage": 1}) == 'node1\tmax_memory_usage\t11111111\n' \
                                                                         'node1\treadonly\t0\n' \
                                                                         'node2\tmax_memory_usage\t10000000000\n' \
                                                                         'node2\treadonly\t1\n'
    assert distributed.query(query, settings={"max_memory_usage": 40000000,
                                              "readonly": 2}) == 'node1\tmax_memory_usage\t40000000\n' \
                                                                 'node1\treadonly\t2\n' \
                                                                 'node2\tmax_memory_usage\t10000000000\n' \
                                                                 'node2\treadonly\t1\n'
    assert distributed.query(query, settings={"max_memory_usage": 3000000000,
                                              "readonly": 2}) == 'node1\tmax_memory_usage\t99999999\n' \
                                                                 'node1\treadonly\t2\n' \
                                                                 'node2\tmax_memory_usage\t10000000000\n' \
                                                                 'node2\treadonly\t1\n'


def test_insert_clamps_settings():
    node1.query("ALTER USER shard SETTINGS max_memory_usage = 50000000 MIN 11111111 MAX 99999999")
    node2.query("ALTER USER shard SETTINGS max_memory_usage = 50000000 MIN 11111111 MAX 99999999")

    distributed.query("INSERT INTO proxy VALUES (toDate('2020-02-20'), 2, 2)")
    distributed.query("INSERT INTO proxy VALUES (toDate('2020-02-21'), 2, 2)", settings={"max_memory_usage": 5000000})
    distributed.query("SYSTEM FLUSH DISTRIBUTED proxy")
    assert_eq_with_retry(distributed, "SELECT COUNT() FROM proxy", "4")