"""连浊关联模块测试。"""
from pl_japanese.learner.rendaku import (
    to_dakuon, to_handakuon, to_seion, rendaku_variants, find_rendaku_links,
    load_rendaku_marks,
)


class TestDakuon:
    def test_seion_to_dakuon(self):
        assert to_dakuon('はこ') == 'ばこ'   # 箱
        assert to_dakuon('かみ') == 'がみ'   # 紙
        assert to_dakuon('と') == 'ど'
        assert to_dakuon('す') == 'ず'

    def test_no_dakuon_returns_none(self):
        assert to_dakuon('あき') is None   # あ 不可浊化
        assert to_dakuon('') is None

    def test_handakuon(self):
        assert to_handakuon('はし') == 'ぱし'
        assert to_handakuon('ほん') == 'ぽん'

    def test_handakuon_only_h_row(self):
        assert to_handakuon('かみ') is None  # か 行无半浊

    def test_to_seion(self):
        assert to_seion('ばこ') == 'はこ'
        assert to_seion('がみ') == 'かみ'
        assert to_seion('ぱし') == 'はし'

    def test_to_seion_none_for_seion(self):
        assert to_seion('はこ') is None  # 已是清音


class TestRendakuVariants:
    def test_seion_variants(self):
        # はこ → ばこ（浊）、ぱこ（半浊）
        variants = rendaku_variants('はこ')
        assert 'ばこ' in variants
        assert 'ぱこ' in variants

    def test_dakuon_variant(self):
        # ばこ → はこ（清）
        assert 'はこ' in rendaku_variants('ばこ')


class TestFindLinks:
    def test_links_within_dataset(self):
        # 数据集里同时有 はこ 和 ばこ 才建立关联
        all_kana = {'はこ', 'ばこ', 'かみ', 'がみ', 'あき'}
        links = find_rendaku_links(all_kana)
        assert 'ばこ' in links['はこ']
        assert 'はこ' in links['ばこ']
        assert 'がみ' in links['かみ']
        assert 'あき' not in links  # 无变体，不建关联

    def test_missing_variant_not_linked(self):
        # ばこ 不在数据集，はこ 不应关联到它
        all_kana = {'はこ', 'かみ'}
        links = find_rendaku_links(all_kana)
        assert 'はこ' not in links  # ばこ/ぱこ 都不在集合


class TestRendakuMarks:
    """显式连浊标注表测试（连用形连浊）。"""

    def test_load_marks(self):
        marks = load_rendaku_marks()
        # 表里应包含连用形连浊条目
        assert marks['付|づけ'] == 'つ'
        assert marks['引|びき'] == 'ひ'
        assert marks['語|がたり'] == 'かた'

    def test_mark_key_format(self):
        """标注表 key 必须是 汉字|读音 格式。"""
        for key in load_rendaku_marks():
            assert '|' in key, f'标注 key 缺 | 分隔: {key}'