import re
from typing import Any
from typing import Optional
from typing import Text
from typing import Tuple

from pypinyin import Style
from pypinyin.contrib._tone_rule import right_mark_index

_re_number = re.compile(r'\d')


class NeutralToneWith5Mixin():
    """声调使用数字表示的相关拼音风格下的结果使用 5 标识轻声。
    使用方法::
        from pypinyin import lazy_pinyin, Style
        from pypinyin.contrib.neutral_tone import NeutralToneWith5Mixin
        from pypinyin.converter import DefaultConverter
        from pypinyin.core import Pinyin
        # 原来的结果中不会标识轻声
        print(lazy_pinyin('好了', style=Style.TONE2))
        # 输出: ['ha3o', 'le']
        class MyConverter(NeutralToneWith5Mixin, DefaultConverter):
            pass
        my_pinyin = Pinyin(MyConverter())
        pinyin = my_pinyin.pinyin
        lazy_pinyin = my_pinyin.lazy_pinyin
        #  新的结果中使用 ``5`` 标识轻声
        print(lazy_pinyin('好了', style=Style.TONE2))
        # 输出: ['ha3o', 'le5']
        print(pinyin('好了', style=Style.TONE2))
        # 输出：[['ha3o'], ['le5']]
    """

    NUMBER_TONE = (Style.TONE2, Style.TONE3, Style.FINALS_TONE2,
                   Style.FINALS_TONE3)  # type: Tuple[Style]
    NUMBER_AT_END = (Style.TONE3, Style.FINALS_TONE3)  # type: Tuple[Style]

    def post_convert_style(self,
                           han: Text,
                           orig_pinyin: Text,
                           converted_pinyin: Text,
                           style: Style,
                           strict: bool,
                           **kwargs: Any) -> Optional[Text]:

        pre_data = super().post_convert_style(
            han, orig_pinyin, converted_pinyin, style, strict, **kwargs)

        if style not in self.NUMBER_TONE:
            return pre_data

        if pre_data is not None:
            converted_pinyin = pre_data

        # 有声调，跳过
        if _re_number.search(converted_pinyin):
            return converted_pinyin

        if style in self.NUMBER_AT_END:
            return '{}5'.format(converted_pinyin)

        # 找到应该在哪个字母上标声调
        mark_index = right_mark_index(converted_pinyin)
        before = converted_pinyin[:mark_index + 1]
        after = converted_pinyin[mark_index + 1:]

        return '{}5{}'.format(before, after)