"""core 包测试。

TODO(L0)：TestValidate 实现后去掉 skip 标记（Result 与 Random 已完成）。
"""

from __future__ import annotations

import numpy as np
import pytest


class TestRandom:
    def test_get_rng_is_reproducible(self):
        from mcm_toolkit.core import get_rng

        assert get_rng(42).random() == get_rng(42).random()

    def test_get_rng_passes_through_generator(self):
        from mcm_toolkit.core import get_rng

        g = np.random.default_rng(0)
        assert get_rng(g) is g

    def test_get_rng_default_follows_global_seed(self):
        """set_seed 之后，不传 random_state 也必须复现——这是"论文能重跑"的底线。"""
        from mcm_toolkit.core import get_rng, set_seed

        set_seed(7)
        first = get_rng().random()
        set_seed(7)
        second = get_rng().random()
        assert first == second

    def test_set_seed_also_covers_third_party_global_state(self):
        """sklearn / statsmodels 走的是 np.random 旧全局，set_seed 要连它一起覆盖。"""
        from mcm_toolkit.core import set_seed

        set_seed(7)
        first = np.random.random()  # noqa: NPY002 - 这里就是要验证旧全局被设上了
        set_seed(7)
        second = np.random.random()  # noqa: NPY002
        assert first == second


@pytest.mark.skip(reason="未实现：见 docs/03-roadmap.md L0")
class TestValidate:
    def test_check_same_length_raises_with_detail(self):
        from mcm_toolkit.core import check_same_length

        with pytest.raises(ValueError, match=r"2.*3|长度"):
            check_same_length([1, 2], [1, 2, 3])

    def test_check_array_rejects_nan(self):
        from mcm_toolkit.core import check_array

        with pytest.raises(ValueError):
            check_array([1.0, np.nan, 2.0], finite=True)

    def test_check_probability_bounds(self):
        from mcm_toolkit.core import check_probability

        assert check_probability(0.5) == 0.5
        with pytest.raises(ValueError):
            check_probability(1.5)

    def test_check_square_matrix(self):
        from mcm_toolkit.core import check_square_matrix

        check_square_matrix([[1, 2], [3, 4]])
        with pytest.raises(ValueError):
            check_square_matrix([[1, 2, 3], [4, 5, 6]])


def test_result_repr_is_readable():
    from mcm_toolkit.core import Result

    text = repr(Result("demo", params={"a": 1}, metrics={"r2": 0.9}))
    # 只断言关键信息在场，不断言完整字符串——否则以后调格式会让测试集体变红
    assert "demo" in text and "r2" in text


def test_result_repr_stays_short_and_safe():
    """默认值、失败结果、十万级数组：repr 都不能崩，也不能刷屏。"""
    from mcm_toolkit.core import Result

    assert "empty" in repr(Result("empty"))

    failed = repr(Result("boom", success=False, message="求解未收敛"))
    assert "success=False" in failed
    assert "求解未收敛" in failed

    noisy = repr(Result("mc", data=np.arange(100_000)))
    assert "ndarray(100000)" in noisy
    assert len(noisy) < 200, "data 不应被整个打印出来"


def test_result_summary_is_markdown_table():
    from mcm_toolkit.core import Result

    result = Result("topsis", params={"n": 3}, metrics={"best": 0.83})
    text = result.summary()
    lines = text.splitlines()

    assert lines[0] == "### topsis"
    assert lines[2] == "| 项 | 值 |"
    assert "| success | True |" in lines
    assert "| params.n | 3 |" in lines
    assert "| metrics.best | 0.83 |" in lines
    assert result.summary() == text, "summary 必须无副作用、可重复调用"


def test_result_summary_appends_message_on_failure():
    from mcm_toolkit.core import Result

    text = Result("gm11", success=False, message="样本太少").summary()
    assert "| success | False |" in text
    assert text.rstrip().endswith("> 样本太少")