import logging
import random
import string
import time
import threading
import os

import pytest
from helpers.cluster import ClickHouseCluster

from pyhdfs import HdfsClient

SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))
CONFIG_PATH = os.path.join(SCRIPT_DIR, './_instances/node/configs/config.d/storage_conf.xml')


def create_table(cluster, table_name, additional_settings=None):
    node = cluster.instances["node"]

    create_table_statement = """
        CREATE TABLE {} (
            dt Date, id Int64, data String,
            INDEX min_max (id) TYPE minmax GRANULARITY 3
        ) ENGINE=MergeTree()
        PARTITION BY dt
        ORDER BY (dt, id)
        SETTINGS
            storage_policy='hdfs',
            old_parts_lifetime=0,
            index_granularity=512
        """.format(table_name)

    if additional_settings:
        create_table_statement += ","
        create_table_statement += additional_settings

    node.query(create_table_statement)


FILES_OVERHEAD = 1
FILES_OVERHEAD_PER_COLUMN = 2  # Data and mark files
FILES_OVERHEAD_PER_PART_WIDE = FILES_OVERHEAD_PER_COLUMN * 3 + 2 + 6 + 1
FILES_OVERHEAD_PER_PART_COMPACT = 10 + 1


def random_string(length):
    letters = string.ascii_letters
    return ''.join(random.choice(letters) for i in range(length))


def generate_values(date_str, count, sign=1):
    data = [[date_str, sign * (i + 1), random_string(10)] for i in range(count)]
    data.sort(key=lambda tup: tup[1])
    return ",".join(["('{}',{},'{}')".format(x, y, z) for x, y, z in data])


@pytest.fixture(scope="module")
def cluster():
    try:
        cluster = ClickHouseCluster(__file__)
        cluster.add_instance("node", main_configs=["configs/config.d/storage_conf.xml",
                                                   "configs/config.d/log_conf.xml"], with_hdfs=True)
        logging.info("Starting cluster...")
        cluster.start()
        logging.info("Cluster started")

        fs = HdfsClient(hosts='localhost')
        fs.mkdirs('/clickhouse')

        logging.info("Created HDFS directory")

        yield cluster
    finally:
        cluster.shutdown()


def wait_for_delete_hdfs_objects(cluster, expected, num_tries=30):
    fs = HdfsClient(hosts='localhost')
    while num_tries > 0:
        num_hdfs_objects = len(fs.listdir('/clickhouse'))
        if num_hdfs_objects == expected:
            break;
        num_tries -= 1
        time.sleep(1)
    assert(len(fs.listdir('/clickhouse')) == expected)


@pytest.fixture(autouse=True)
def drop_table(cluster):
    node = cluster.instances["node"]

    fs = HdfsClient(hosts='localhost')
    hdfs_objects = fs.listdir('/clickhouse')
    print('Number of hdfs objects to delete:', len(hdfs_objects), sep=' ')

    node.query("DROP TABLE IF EXISTS hdfs_test SYNC")

    try:
        wait_for_delete_hdfs_objects(cluster, 0)
    finally:
        hdfs_objects = fs.listdir('/clickhouse')
        if len(hdfs_objects) == 0:
            return
        print("Manually removing extra objects to prevent tests cascade failing: ", hdfs_objects)
        for path in hdfs_objects:
            fs.delete(path)


@pytest.mark.parametrize("min_rows_for_wide_part,files_per_part", [(0, FILES_OVERHEAD_PER_PART_WIDE), (8192, FILES_OVERHEAD_PER_PART_COMPACT)])
def test_simple_insert_select(cluster, min_rows_for_wide_part, files_per_part):
    create_table(cluster, "hdfs_test", additional_settings="min_rows_for_wide_part={}".format(min_rows_for_wide_part))

    node = cluster.instances["node"]

    values1 = generate_values('2020-01-03', 4096)
    node.query("INSERT INTO hdfs_test VALUES {}".format(values1))
    assert node.query("SELECT * FROM hdfs_test order by dt, id FORMAT Values") == values1

    fs = HdfsClient(hosts='localhost')

    hdfs_objects = fs.listdir('/clickhouse')
    print(hdfs_objects)
    assert len(hdfs_objects) == FILES_OVERHEAD + files_per_part

    values2 = generate_values('2020-01-04', 4096)
    node.query("INSERT INTO hdfs_test VALUES {}".format(values2))
    assert node.query("SELECT * FROM hdfs_test ORDER BY dt, id FORMAT Values") == values1 + "," + values2

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + files_per_part * 2

    assert node.query("SELECT count(*) FROM hdfs_test where id = 1 FORMAT Values") == "(2)"


def test_alter_table_columns(cluster):
    create_table(cluster, "hdfs_test")

    node = cluster.instances["node"]
    fs = HdfsClient(hosts='localhost')

    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-03', 4096)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-03', 4096, -1)))

    node.query("ALTER TABLE hdfs_test ADD COLUMN col1 UInt64 DEFAULT 1")
    # To ensure parts have merged
    node.query("OPTIMIZE TABLE hdfs_test")

    assert node.query("SELECT sum(col1) FROM hdfs_test FORMAT Values") == "(8192)"
    assert node.query("SELECT sum(col1) FROM hdfs_test WHERE id > 0 FORMAT Values") == "(4096)"
    wait_for_delete_hdfs_objects(cluster, FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE + FILES_OVERHEAD_PER_COLUMN)

    node.query("ALTER TABLE hdfs_test MODIFY COLUMN col1 String", settings={"mutations_sync": 2})

    assert node.query("SELECT distinct(col1) FROM hdfs_test FORMAT Values") == "('1')"
    # and file with mutation
    wait_for_delete_hdfs_objects(cluster, FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE + FILES_OVERHEAD_PER_COLUMN + 1)

    node.query("ALTER TABLE hdfs_test DROP COLUMN col1", settings={"mutations_sync": 2})

    # and 2 files with mutations
    wait_for_delete_hdfs_objects(cluster, FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE + 2)


def test_attach_detach_partition(cluster):
    create_table(cluster, "hdfs_test")

    node = cluster.instances["node"]
    fs = HdfsClient(hosts='localhost')

    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-03', 4096)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-04', 4096)))
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(8192)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 2

    node.query("ALTER TABLE hdfs_test DETACH PARTITION '2020-01-03'")
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(4096)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 2

    node.query("ALTER TABLE hdfs_test ATTACH PARTITION '2020-01-03'")
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(8192)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 2

    node.query("ALTER TABLE hdfs_test DROP PARTITION '2020-01-03'")
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(4096)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE

    node.query("ALTER TABLE hdfs_test DETACH PARTITION '2020-01-04'")
    node.query("ALTER TABLE hdfs_test DROP DETACHED PARTITION '2020-01-04'", settings={"allow_drop_detached": 1})
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(0)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD


def test_move_partition_to_another_disk(cluster):
    create_table(cluster, "hdfs_test")

    node = cluster.instances["node"]
    fs = HdfsClient(hosts='localhost')

    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-03', 4096)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-04', 4096)))
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(8192)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 2

    node.query("ALTER TABLE hdfs_test MOVE PARTITION '2020-01-04' TO DISK 'hdd'")
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(8192)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE

    node.query("ALTER TABLE hdfs_test MOVE PARTITION '2020-01-04' TO DISK 'hdfs'")
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(8192)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 2


def test_table_manipulations(cluster):
    create_table(cluster, "hdfs_test")

    node = cluster.instances["node"]
    fs = HdfsClient(hosts='localhost')

    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-03', 4096)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-04', 4096)))

    node.query("RENAME TABLE hdfs_test TO hdfs_renamed")
    assert node.query("SELECT count(*) FROM hdfs_renamed FORMAT Values") == "(8192)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 2

    node.query("RENAME TABLE hdfs_renamed TO hdfs_test")
    assert node.query("CHECK TABLE hdfs_test FORMAT Values") == "(1)"

    node.query("DETACH TABLE hdfs_test")
    node.query("ATTACH TABLE hdfs_test")
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(8192)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 2

    node.query("TRUNCATE TABLE hdfs_test")
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(0)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD


def test_move_replace_partition_to_another_table(cluster):
    create_table(cluster, "hdfs_test")

    node = cluster.instances["node"]
    fs = HdfsClient(hosts='localhost')

    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-03', 4096)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-04', 4096)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-05', 4096, -1)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-06', 4096, -1)))
    assert node.query("SELECT sum(id) FROM hdfs_test FORMAT Values") == "(0)"
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(16384)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 4

    create_table(cluster, "hdfs_clone")

    node.query("ALTER TABLE hdfs_test MOVE PARTITION '2020-01-03' TO TABLE hdfs_clone")
    node.query("ALTER TABLE hdfs_test MOVE PARTITION '2020-01-05' TO TABLE hdfs_clone")
    assert node.query("SELECT sum(id) FROM hdfs_test FORMAT Values") == "(0)"
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(8192)"
    assert node.query("SELECT sum(id) FROM hdfs_clone FORMAT Values") == "(0)"
    assert node.query("SELECT count(*) FROM hdfs_clone FORMAT Values") == "(8192)"

    # Number of objects in HDFS should be unchanged.
    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD * 2 + FILES_OVERHEAD_PER_PART_WIDE * 4

    # Add new partitions to source table, but with different values and replace them from copied table.
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-03', 4096, -1)))
    node.query("INSERT INTO hdfs_test VALUES {}".format(generate_values('2020-01-05', 4096)))
    assert node.query("SELECT sum(id) FROM hdfs_test FORMAT Values") == "(0)"
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(16384)"

    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD * 2 + FILES_OVERHEAD_PER_PART_WIDE * 6

    node.query("ALTER TABLE hdfs_test REPLACE PARTITION '2020-01-03' FROM hdfs_clone")
    node.query("ALTER TABLE hdfs_test REPLACE PARTITION '2020-01-05' FROM hdfs_clone")
    assert node.query("SELECT sum(id) FROM hdfs_test FORMAT Values") == "(0)"
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(16384)"
    assert node.query("SELECT sum(id) FROM hdfs_clone FORMAT Values") == "(0)"
    assert node.query("SELECT count(*) FROM hdfs_clone FORMAT Values") == "(8192)"

    # Wait for outdated partitions deletion.
    print(1)
    wait_for_delete_hdfs_objects(cluster, FILES_OVERHEAD * 2 + FILES_OVERHEAD_PER_PART_WIDE * 4)

    node.query("DROP TABLE hdfs_clone NO DELAY")
    assert node.query("SELECT sum(id) FROM hdfs_test FORMAT Values") == "(0)"
    assert node.query("SELECT count(*) FROM hdfs_test FORMAT Values") == "(16384)"

    # Data should remain in hdfs
    hdfs_objects = fs.listdir('/clickhouse')
    assert len(hdfs_objects) == FILES_OVERHEAD + FILES_OVERHEAD_PER_PART_WIDE * 4