import pytest
import pandas as pd
from unittest.mock import patch
from dagster import DagsterInvalidInvocationError, build_op_context

from template_code_location.dataframe_level_anonymisation.ops import (
    apply_k_anonymity,
    apply_l_diversity,
    apply_t_closeness,
)
from template_code_location.dataframe_level_anonymisation.config_models import (
    KAnonymityConfiguration,
    LDiversityConfiguration,
    TClosenessConfiguration,
)


# ---------------------------
# Fixtures
# ---------------------------
@pytest.fixture
def fake_df():
    return pd.DataFrame({"id": [1, 2], "age": [30, 40]})


@pytest.fixture
def k_config():
    return KAnonymityConfiguration(
        ident=["id"],
        quasi_identifiers=["age"],
        sensitive_attributes=["age"],
        k=2,
        supp_level=0.0,
        generalisation_hierarchies={"age": "simpl_age"},
    )


@pytest.fixture
def l_config():
    return LDiversityConfiguration(
        ident=["id"],
        quasi_identifiers=["age"],
        sensitive_attribute="age",
        k=2,
        l=1,
        supp_level=0.0,
        generalisation_hierarchies={"age": "simpl_age"},
    )


@pytest.fixture
def t_config():
    return TClosenessConfiguration(
        ident=["id"],
        quasi_identifiers=["age"],
        sensitive_attribute="age",
        k=2,
        t=0.5,
        supp_level=0.0,
        generalisation_hierarchies={"age": "simpl_age"},
    )


@pytest.fixture
def op_context():
    return build_op_context()


# ---------------------------
# Helper for patching external functions
# ---------------------------
@pytest.fixture(autouse=True)
def patch_external_ops():
    with (
        patch(
            "dataframe_level_anonymisation.ops.get_all_hierarchies",
            return_value={"simpl_age": {0: [30, 40]}},
        ),
        patch(
            "dataframe_level_anonymisation.ops.k_anonymity",
            return_value=pd.DataFrame({"id": [1, 2], "age": [30, 40]}),
        ),
        patch(
            "dataframe_level_anonymisation.ops.l_diversity",
            return_value=pd.DataFrame({"id": [1, 2], "age": [30, 40]}),
        ),
        patch(
            "dataframe_level_anonymisation.ops.t_closeness",
            return_value=pd.DataFrame({"id": [1, 2], "age": [30, 40]}),
        ),
    ):
        yield


# ---------------------------
# Tests for apply_k_anonymity
# ---------------------------
def test_apply_k_anonymity_outputs(op_context, k_config, fake_df):
    results = list(apply_k_anonymity(op_context, k_config, fake_df))
    assert len(results) == 2

    data_output = results[0].value
    metrics_output = results[1].value

    # Check types
    assert isinstance(data_output, pd.DataFrame)
    assert isinstance(metrics_output, dict)
    assert "k_anon" in metrics_output
    assert "l_div" in metrics_output
    assert "t_clos" in metrics_output


# ---------------------------
# Tests for apply_l_diversity
# ---------------------------
def test_apply_l_diversity_outputs(op_context, l_config, fake_df):
    results = list(apply_l_diversity(op_context, l_config, fake_df))
    assert len(results) == 2

    data_output = results[0].value
    metrics_output = results[1].value

    assert isinstance(data_output, pd.DataFrame)
    assert isinstance(metrics_output, dict)
    assert "k_anon" in metrics_output
    assert "l_div" in metrics_output
    assert "t_clos" in metrics_output


def test_apply_l_diversity_empty_raises(op_context, l_config):
    with patch("dataframe_level_anonymisation.ops.l_diversity", return_value=pd.DataFrame()):

        with pytest.raises(DagsterInvalidInvocationError):
            list(apply_l_diversity(op_context, l_config, pd.DataFrame({"id": [1], "age": [30]})))


# ---------------------------
# Tests for apply_t_closeness
# ---------------------------
def test_apply_t_closeness_outputs(op_context, t_config, fake_df):
    results = list(apply_t_closeness(op_context, t_config, fake_df))
    assert len(results) == 2

    data_output = results[0].value
    metrics_output = results[1].value

    assert isinstance(data_output, pd.DataFrame)
    assert isinstance(metrics_output, dict)
    assert "k_anon" in metrics_output
    assert "l_div" in metrics_output
    assert "t_clos" in metrics_output


def test_apply_t_closeness_empty_raises(op_context, t_config):
    with patch("dataframe_level_anonymisation.ops.t_closeness", return_value=pd.DataFrame()):
        with pytest.raises(DagsterInvalidInvocationError):
            list(apply_t_closeness(op_context, t_config, pd.DataFrame({"id": [1], "age": [30]})))


# ---------------------------
# Additional tests for _validate_and_get_hierarchies
# ---------------------------
def test_validate_hierarchies_dataset_too_small(k_config):
    small_df = pd.DataFrame({"id": [1], "age": [30]})
    from template_code_location.dataframe_level_anonymisation.ops import _validate_and_get_hierarchies

    with pytest.raises(DagsterInvalidInvocationError):
        _validate_and_get_hierarchies(k_config, small_df)


def test_validate_hierarchies_missing_hierarchy(k_config, fake_df):
    from template_code_location.dataframe_level_anonymisation.ops import _validate_and_get_hierarchies

    bad_config = k_config.model_copy(update={"generalisation_hierarchies": {}})

    with pytest.raises(DagsterInvalidInvocationError):
        _validate_and_get_hierarchies(bad_config, fake_df)


def test_validate_hierarchies_hierarchy_not_in_code(k_config, fake_df):
    from template_code_location.dataframe_level_anonymisation.ops import _validate_and_get_hierarchies

    with patch("dataframe_level_anonymisation.ops.get_all_hierarchies", return_value={}):
        with pytest.raises(DagsterInvalidInvocationError):
            _validate_and_get_hierarchies(k_config, fake_df)


# ---------------------------
# Additional tests for _calc_dataframe_metrics
# ---------------------------
def test_calc_dataframe_metrics_basic():
    from template_code_location.dataframe_level_anonymisation.ops import _calc_dataframe_metrics

    df_org = pd.DataFrame({"age": [30, 40], "id": [1, 2]})
    df_anon = df_org.copy()

    with (
        patch("dataframe_level_anonymisation.ops.anonymity.k_anonymity", return_value=2),
        patch("dataframe_level_anonymisation.ops.anonymity.l_diversity", return_value=1),
        patch("dataframe_level_anonymisation.ops.anonymity.t_closeness", return_value=0.1),
    ):

        report, metrics = _calc_dataframe_metrics(df_anon, df_org, ["age"], ["age"])

        assert "k-anonymity" in report
        assert metrics["k_anon"] == 2
        assert metrics["l_div"] == 1
        assert metrics["t_clos"] == 0.1


# ---------------------------
# Tests for apply_t_closeness exception branches
# ---------------------------
def test_apply_t_closeness_value_error_quasi_identifiers(op_context, t_config, fake_df):
    """Covers the branch where ValueError contains 'Cannot be quasi-identifiers'."""
    with patch(
        "dataframe_level_anonymisation.ops.t_closeness",
        side_effect=ValueError("Cannot be quasi-identifiers invalid"),
    ):
        with pytest.raises(DagsterInvalidInvocationError):
            list(apply_t_closeness(op_context, t_config, fake_df))


def test_apply_t_closeness_value_error_other_message(op_context, t_config, fake_df):
    """Covers the branch where ValueError is raised but message does NOT contain that substring."""
    with patch(
        "dataframe_level_anonymisation.ops.t_closeness", side_effect=ValueError("Some other error")
    ):
        with pytest.raises(DagsterInvalidInvocationError):
            list(apply_t_closeness(op_context, t_config, fake_df))