from posixpath import join as pjoin

import pytest

import ibis
from ibis.backends.impala.compat import HS2Error
from ibis.tests.util import assert_equal

pytestmark = pytest.mark.impala


def test_cleanup_tmp_table_on_gc(con, test_data_dir):
    import gc

    hdfs_path = pjoin(test_data_dir, 'parquet/tpch_region')
    table = con.parquet_file(hdfs_path)
    name = table.op().name
    table = None
    gc.collect()
    assert not con.exists_table(name)


def test_persist_parquet_file_with_name(con, test_data_dir, temp_table_db):
    import gc

    hdfs_path = pjoin(test_data_dir, 'parquet/tpch_region')

    tmp_db, name = temp_table_db
    schema = ibis.schema(
        [
            ('r_regionkey', 'int16'),
            ('r_name', 'string'),
            ('r_comment', 'string'),
        ]
    )
    con.parquet_file(
        hdfs_path, schema=schema, name=name, database=tmp_db, persist=True
    )
    gc.collect()

    # table still exists
    con.table(name, database=tmp_db)


def test_query_parquet_file_with_schema(con, test_data_dir):
    hdfs_path = pjoin(test_data_dir, 'parquet/tpch_region')

    schema = ibis.schema(
        [
            ('r_regionkey', 'int16'),
            ('r_name', 'string'),
            ('r_comment', 'string'),
        ]
    )

    table = con.parquet_file(hdfs_path, schema=schema)

    name = table.op().name

    # table exists
    con.table(name)

    expr = table.r_name.value_counts()
    expr.execute()

    assert table.count().execute() == 5


def test_query_parquet_file_like_table(con, test_data_dir):
    hdfs_path = pjoin(test_data_dir, 'parquet/tpch_region')

    ex_schema = ibis.schema(
        [
            ('r_regionkey', 'int16'),
            ('r_name', 'string'),
            ('r_comment', 'string'),
        ]
    )

    table = con.parquet_file(hdfs_path, like_table='tpch_region')

    assert_equal(table.schema(), ex_schema)


def test_query_parquet_infer_schema(con, test_data_dir):
    hdfs_path = pjoin(test_data_dir, 'parquet/tpch_region')
    table = con.parquet_file(hdfs_path)

    # NOTE: the actual schema should have an int16, but bc this is being
    # inferred from a parquet file, which has no notion of int16, the
    # inferred schema will have an int32 instead.
    ex_schema = ibis.schema(
        [
            ('r_regionkey', 'int32'),
            ('r_name', 'string'),
            ('r_comment', 'string'),
        ]
    )

    assert_equal(table.schema(), ex_schema)


def test_create_table_persist_fails_if_called_twice(
    con, temp_table_db, test_data_dir
):
    tmp_db, tname = temp_table_db

    hdfs_path = pjoin(test_data_dir, 'parquet/tpch_region')
    con.parquet_file(hdfs_path, name=tname, persist=True, database=tmp_db)

    with pytest.raises(HS2Error):
        con.parquet_file(hdfs_path, name=tname, persist=True, database=tmp_db)
