"""Test for utils hfa.py."""

import pandas as pd
import pytest
from src.utils import dataframes


def test_dict_to_dataframe():
    """Test dict_to_dataframe return expected success response."""
    records = [
        {'id': 1, 'name': 'Alice'},
        {'id': 2, 'name': 'Bob'}
    ]
    dtypes = {'id': 'int64', 'name': 'string'}

    df = dataframes.dict_to_dataframe(records, dtypes=dtypes)

    assert isinstance(df, pd.DataFrame)
    assert list(df.columns) == ['id', 'name']
    assert df.dtypes['id'] == 'int64'
    assert df.dtypes['name'] == 'string'
    assert df.shape == (2, 2)


def test_dict_to_dataframe_empty():
    """Test dict_to_dataframe return empty response."""
    df = dataframes.dict_to_dataframe([])
    assert isinstance(df, pd.DataFrame)
    assert df.empty


@pytest.mark.parametrize(
    'dfs, columns, drop_duplicates, ignore_index, expected_dict',
    [
        pytest.param(
            [
                pd.DataFrame({'a': [1, 2], 'b': [3, 4]}),
                pd.DataFrame({'a': [5], 'b': [6]}),
            ],
            None,
            False,
            True,
            [
                {'a': 1, 'b': 3},
                {'a': 2, 'b': 4},
                {'a': 5, 'b': 6},
            ],
            id='basic concat, no drop duplicates, no columns filter',
        ),
        pytest.param(
            [
                pd.DataFrame({'a': [1, 2], 'b': [3, 4]}),
                pd.DataFrame({'a': [5], 'b': [6]}),
            ],
            ['a'],
            False,
            True,
            [
                {'a': 1},
                {'a': 2},
                {'a': 5},
            ],
            id='select columns after concat',
        ),
        pytest.param(
            [
                pd.DataFrame({'a': [1, 2, 2], 'b': [3, 4, 4]}),
                pd.DataFrame({'a': [2, 3], 'b': [4, 5]}),
            ],
            None,
            True,
            True,
            [
                {'a': 1, 'b': 3},
                {'a': 2, 'b': 4},
                {'a': 3, 'b': 5},
            ],
            id='drop duplicates',
        ),
        pytest.param(
            [],
            ['a', 'b'],
            False,
            True,
            [],
            id='empty list of dataframes returns empty with columns',
        ),
        pytest.param(
            [
                pd.DataFrame({'a': [1, 2]}, index=[10, 11]),
                pd.DataFrame({'a': [3]}, index=[20]),
            ],
            None,
            False,
            False,
            [
                {'a': 1},
                {'a': 2},
                {'a': 3},
            ],
            id='preserve index when ignore_index=False',
        ),
    ],
)
def test_merge_dataframes(dfs, columns, drop_duplicates, ignore_index, expected_dict):
    """Test merge_dataframes returns dataframe."""
    result = dataframes.merge_dataframes(
        dataframes=dfs, columns=columns, drop_duplicates=drop_duplicates, ignore_index=ignore_index
    )
    assert result.to_dict(orient='records') == expected_dict