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# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from typing import List
from typing import Tuple

import jieba
from pypinyin import lazy_pinyin
from pypinyin import Style


class ToneSandhi:
    def __init__(self):
        self.must_neural_tone_words = {
            "麻烦",
            "麻利",
            "鸳鸯",
            "高粱",
            "骨头",
            "骆驼",
            "马虎",
            "首饰",
            "馒头",
            "馄饨",
            "风筝",
            "难为",
            "队伍",
            "阔气",
            "闺女",
            "门道",
            "锄头",
            "铺盖",
            "铃铛",
            "铁匠",
            "钥匙",
            "里脊",
            "里头",
            "部分",
            "那么",
            "道士",
            "造化",
            "迷糊",
            "连累",
            "这么",
            "这个",
            "运气",
            "过去",
            "软和",
            "转悠",
            "踏实",
            "跳蚤",
            "跟头",
            "趔趄",
            "财主",
            "豆腐",
            "讲究",
            "记性",
            "记号",
            "认识",
            "规矩",
            "见识",
            "裁缝",
            "补丁",
            "衣裳",
            "衣服",
            "衙门",
            "街坊",
            "行李",
            "行当",
            "蛤蟆",
            "蘑菇",
            "薄荷",
            "葫芦",
            "葡萄",
            "萝卜",
            "荸荠",
            "苗条",
            "苗头",
            "苍蝇",
            "芝麻",
            "舒服",
            "舒坦",
            "舌头",
            "自在",
            "膏药",
            "脾气",
            "脑袋",
            "脊梁",
            "能耐",
            "胳膊",
            "胭脂",
            "胡萝",
            "胡琴",
            "胡同",
            "聪明",
            "耽误",
            "耽搁",
            "耷拉",
            "耳朵",
            "老爷",
            "老实",
            "老婆",
            "老头",
            "老太",
            "翻腾",
            "罗嗦",
            "罐头",
            "编辑",
            "结实",
            "红火",
            "累赘",
            "糨糊",
            "糊涂",
            "精神",
            "粮食",
            "簸箕",
            "篱笆",
            "算计",
            "算盘",
            "答应",
            "笤帚",
            "笑语",
            "笑话",
            "窟窿",
            "窝囊",
            "窗户",
            "稳当",
            "稀罕",
            "称呼",
            "秧歌",
            "秀气",
            "秀才",
            "福气",
            "祖宗",
            "砚台",
            "码头",
            "石榴",
            "石头",
            "石匠",
            "知识",
            "眼睛",
            "眯缝",
            "眨巴",
            "眉毛",
            "相声",
            "盘算",
            "白净",
            "痢疾",
            "痛快",
            "疟疾",
            "疙瘩",
            "疏忽",
            "畜生",
            "生意",
            "甘蔗",
            "琵琶",
            "琢磨",
            "琉璃",
            "玻璃",
            "玫瑰",
            "玄乎",
            "狐狸",
            "状元",
            "特务",
            "牲口",
            "牙碜",
            "牌楼",
            "爽快",
            "爱人",
            "热闹",
            "烧饼",
            "烟筒",
            "烂糊",
            "点心",
            "炊帚",
            "灯笼",
            "火候",
            "漂亮",
            "滑溜",
            "溜达",
            "温和",
            "清楚",
            "消息",
            "浪头",
            "活泼",
            "比方",
            "正经",
            "欺负",
            "模糊",
            "槟榔",
            "棺材",
            "棒槌",
            "棉花",
            "核桃",
            "栅栏",
            "柴火",
            "架势",
            "枕头",
            "枇杷",
            "机灵",
            "本事",
            "木头",
            "木匠",
            "朋友",
            "月饼",
            "月亮",
            "暖和",
            "明白",
            "时候",
            "新鲜",
            "故事",
            "收拾",
            "收成",
            "提防",
            "挖苦",
            "挑剔",
            "指甲",
            "指头",
            "拾掇",
            "拳头",
            "拨弄",
            "招牌",
            "招呼",
            "抬举",
            "护士",
            "折腾",
            "扫帚",
            "打量",
            "打算",
            "打点",
            "打扮",
            "打听",
            "打发",
            "扎实",
            "扁担",
            "戒指",
            "懒得",
            "意识",
            "意思",
            "情形",
            "悟性",
            "怪物",
            "思量",
            "怎么",
            "念头",
            "念叨",
            "快活",
            "忙活",
            "志气",
            "心思",
            "得罪",
            "张罗",
            "弟兄",
            "开通",
            "应酬",
            "庄稼",
            "干事",
            "帮手",
            "帐篷",
            "希罕",
            "师父",
            "师傅",
            "巴结",
            "巴掌",
            "差事",
            "工夫",
            "岁数",
            "屁股",
            "尾巴",
            "少爷",
            "小气",
            "小伙",
            "将就",
            "对头",
            "对付",
            "寡妇",
            "家伙",
            "客气",
            "实在",
            "官司",
            "学问",
            "学生",
            "字号",
            "嫁妆",
            "媳妇",
            "媒人",
            "婆家",
            "娘家",
            "委屈",
            "姑娘",
            "姐夫",
            "妯娌",
            "妥当",
            "妖精",
            "奴才",
            "女婿",
            "头发",
            "太阳",
            "大爷",
            "大方",
            "大意",
            "大夫",
            "多少",
            "多么",
            "外甥",
            "壮实",
            "地道",
            "地方",
            "在乎",
            "困难",
            "嘴巴",
            "嘱咐",
            "嘟囔",
            "嘀咕",
            "喜欢",
            "喇嘛",
            "喇叭",
            "商量",
            "唾沫",
            "哑巴",
            "哈欠",
            "哆嗦",
            "咳嗽",
            "和尚",
            "告诉",
            "告示",
            "含糊",
            "吓唬",
            "后头",
            "名字",
            "名堂",
            "合同",
            "吆喝",
            "叫唤",
            "口袋",
            "厚道",
            "厉害",
            "千斤",
            "包袱",
            "包涵",
            "匀称",
            "勤快",
            "动静",
            "动弹",
            "功夫",
            "力气",
            "前头",
            "刺猬",
            "刺激",
            "别扭",
            "利落",
            "利索",
            "利害",
            "分析",
            "出息",
            "凑合",
            "凉快",
            "冷战",
            "冤枉",
            "冒失",
            "养活",
            "关系",
            "先生",
            "兄弟",
            "便宜",
            "使唤",
            "佩服",
            "作坊",
            "体面",
            "位置",
            "似的",
            "伙计",
            "休息",
            "什么",
            "人家",
            "亲戚",
            "亲家",
            "交情",
            "云彩",
            "事情",
            "买卖",
            "主意",
            "丫头",
            "丧气",
            "两口",
            "东西",
            "东家",
            "世故",
            "不由",
            "不在",
            "下水",
            "下巴",
            "上头",
            "上司",
            "丈夫",
            "丈人",
            "一辈",
            "那个",
            "菩萨",
            "父亲",
            "母亲",
            "咕噜",
            "邋遢",
            "费用",
            "冤家",
            "甜头",
            "介绍",
            "荒唐",
            "大人",
            "泥鳅",
            "幸福",
            "熟悉",
            "计划",
            "扑腾",
            "蜡烛",
            "姥爷",
            "照顾",
            "喉咙",
            "吉他",
            "弄堂",
            "蚂蚱",
            "凤凰",
            "拖沓",
            "寒碜",
            "糟蹋",
            "倒腾",
            "报复",
            "逻辑",
            "盘缠",
            "喽啰",
            "牢骚",
            "咖喱",
            "扫把",
            "惦记",
        }
        self.must_not_neural_tone_words = {
            "男子",
            "女子",
            "分子",
            "原子",
            "量子",
            "莲子",
            "石子",
            "瓜子",
            "电子",
            "人人",
            "虎虎",
        }
        self.punc = ":,;。?!“”‘’':,;.?!"

    # the meaning of jieba pos tag: https://blog.csdn.net/weixin_44174352/article/details/113731041
    # e.g.
    # word: "家里"
    # pos: "s"
    # finals: ['ia1', 'i3']
    def _neural_sandhi(self, word: str, pos: str, finals: List[str]) -> List[str]:
        # reduplication words for n. and v. e.g. 奶奶, 试试, 旺旺
        for j, item in enumerate(word):
            if (
                j - 1 >= 0
                and item == word[j - 1]
                and pos[0] in {"n", "v", "a"}
                and word not in self.must_not_neural_tone_words
            ):
                finals[j] = finals[j][:-1] + "5"
        ge_idx = word.find("个")
        if len(word) >= 1 and word[-1] in "吧呢啊呐噻嘛吖嗨呐哦哒额滴哩哟喽啰耶喔诶":
            finals[-1] = finals[-1][:-1] + "5"
        elif len(word) >= 1 and word[-1] in "的地得":
            finals[-1] = finals[-1][:-1] + "5"
        # e.g. 走了, 看着, 去过
        # elif len(word) == 1 and word in "了着过" and pos in {"ul", "uz", "ug"}:
        #     finals[-1] = finals[-1][:-1] + "5"
        elif (
            len(word) > 1
            and word[-1] in "们子"
            and pos in {"r", "n"}
            and word not in self.must_not_neural_tone_words
        ):
            finals[-1] = finals[-1][:-1] + "5"
        # e.g. 桌上, 地下, 家里
        elif len(word) > 1 and word[-1] in "上下里" and pos in {"s", "l", "f"}:
            finals[-1] = finals[-1][:-1] + "5"
        # e.g. 上来, 下去
        elif len(word) > 1 and word[-1] in "来去" and word[-2] in "上下进出回过起开":
            finals[-1] = finals[-1][:-1] + "5"
        # 个做量词
        elif (
            ge_idx >= 1
            and (word[ge_idx - 1].isnumeric() or word[ge_idx - 1] in "几有两半多各整每做是")
        ) or word == "个":
            finals[ge_idx] = finals[ge_idx][:-1] + "5"
        else:
            if (
                word in self.must_neural_tone_words
                or word[-2:] in self.must_neural_tone_words
            ):
                finals[-1] = finals[-1][:-1] + "5"

        word_list = self._split_word(word)
        finals_list = [finals[: len(word_list[0])], finals[len(word_list[0]) :]]
        for i, word in enumerate(word_list):
            # conventional neural in Chinese
            if (
                word in self.must_neural_tone_words
                or word[-2:] in self.must_neural_tone_words
            ):
                finals_list[i][-1] = finals_list[i][-1][:-1] + "5"
        finals = sum(finals_list, [])
        return finals

    def _bu_sandhi(self, word: str, finals: List[str]) -> List[str]:
        # e.g. 看不懂
        if len(word) == 3 and word[1] == "不":
            finals[1] = finals[1][:-1] + "5"
        else:
            for i, char in enumerate(word):
                # "不" before tone4 should be bu2, e.g. 不怕
                if char == "不" and i + 1 < len(word) and finals[i + 1][-1] == "4":
                    finals[i] = finals[i][:-1] + "2"
        return finals

    def _yi_sandhi(self, word: str, finals: List[str]) -> List[str]:
        # "一" in number sequences, e.g. 一零零, 二一零
        if word.find("一") != -1 and all(
            [item.isnumeric() for item in word if item != "一"]
        ):
            return finals
        # "一" between reduplication words should be yi5, e.g. 看一看
        elif len(word) == 3 and word[1] == "一" and word[0] == word[-1]:
            finals[1] = finals[1][:-1] + "5"
        # when "一" is ordinal word, it should be yi1
        elif word.startswith("第一"):
            finals[1] = finals[1][:-1] + "1"
        else:
            for i, char in enumerate(word):
                if char == "一" and i + 1 < len(word):
                    # "一" before tone4 should be yi2, e.g. 一段
                    if finals[i + 1][-1] == "4":
                        finals[i] = finals[i][:-1] + "2"
                    # "一" before non-tone4 should be yi4, e.g. 一天
                    else:
                        # "一" 后面如果是标点,还读一声
                        if word[i + 1] not in self.punc:
                            finals[i] = finals[i][:-1] + "4"
        return finals

    def _split_word(self, word: str) -> List[str]:
        word_list = jieba.cut_for_search(word)
        word_list = sorted(word_list, key=lambda i: len(i), reverse=False)
        first_subword = word_list[0]
        first_begin_idx = word.find(first_subword)
        if first_begin_idx == 0:
            second_subword = word[len(first_subword) :]
            new_word_list = [first_subword, second_subword]
        else:
            second_subword = word[: -len(first_subword)]
            new_word_list = [second_subword, first_subword]
        return new_word_list

    def _three_sandhi(self, word: str, finals: List[str]) -> List[str]:
        if len(word) == 2 and self._all_tone_three(finals):
            finals[0] = finals[0][:-1] + "2"
        elif len(word) == 3:
            word_list = self._split_word(word)
            if self._all_tone_three(finals):
                #  disyllabic + monosyllabic, e.g. 蒙古/包
                if len(word_list[0]) == 2:
                    finals[0] = finals[0][:-1] + "2"
                    finals[1] = finals[1][:-1] + "2"
                #  monosyllabic + disyllabic, e.g. 纸/老虎
                elif len(word_list[0]) == 1:
                    finals[1] = finals[1][:-1] + "2"
            else:
                finals_list = [finals[: len(word_list[0])], finals[len(word_list[0]) :]]
                if len(finals_list) == 2:
                    for i, sub in enumerate(finals_list):
                        # e.g. 所有/人
                        if self._all_tone_three(sub) and len(sub) == 2:
                            finals_list[i][0] = finals_list[i][0][:-1] + "2"
                        # e.g. 好/喜欢
                        elif (
                            i == 1
                            and not self._all_tone_three(sub)
                            and finals_list[i][0][-1] == "3"
                            and finals_list[0][-1][-1] == "3"
                        ):
                            finals_list[0][-1] = finals_list[0][-1][:-1] + "2"
                        finals = sum(finals_list, [])
        # split idiom into two words who's length is 2
        elif len(word) == 4:
            finals_list = [finals[:2], finals[2:]]
            finals = []
            for sub in finals_list:
                if self._all_tone_three(sub):
                    sub[0] = sub[0][:-1] + "2"
                finals += sub

        return finals

    def _all_tone_three(self, finals: List[str]) -> bool:
        return all(x[-1] == "3" for x in finals)

    # merge "不" and the word behind it
    # if don't merge, "不" sometimes appears alone according to jieba, which may occur sandhi error
    def _merge_bu(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = []
        last_word = ""
        for word, pos in seg:
            if last_word == "不":
                word = last_word + word
            if word != "不":
                new_seg.append((word, pos))
            last_word = word[:]
        if last_word == "不":
            new_seg.append((last_word, "d"))
            last_word = ""
        return new_seg

    # function 1: merge "一" and reduplication words in it's left and right, e.g. "听","一","听" ->"听一听"
    # function 2: merge single  "一" and the word behind it
    # if don't merge, "一" sometimes appears alone according to jieba, which may occur sandhi error
    # e.g.
    # input seg: [('听', 'v'), ('一', 'm'), ('听', 'v')]
    # output seg: [['听一听', 'v']]
    def _merge_yi(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = [] * len(seg)
        # function 1
        i = 0
        while i < len(seg):
            word, pos = seg[i]
            if (
                i - 1 >= 0
                and word == "一"
                and i + 1 < len(seg)
                and seg[i - 1][0] == seg[i + 1][0]
                and seg[i - 1][1] == "v"
            ):
                new_seg[i - 1][0] = new_seg[i - 1][0] + "一" + new_seg[i - 1][0]
                i += 2
            else:
                if (
                    i - 2 >= 0
                    and seg[i - 1][0] == "一"
                    and seg[i - 2][0] == word
                    and pos == "v"
                ):
                    continue
                else:
                    new_seg.append([word, pos])
                i += 1
        seg = [i for i in new_seg if len(i) > 0]
        new_seg = []
        # function 2
        for i, (word, pos) in enumerate(seg):
            if new_seg and new_seg[-1][0] == "一":
                new_seg[-1][0] = new_seg[-1][0] + word
            else:
                new_seg.append([word, pos])
        return new_seg

    # the first and the second words are all_tone_three
    def _merge_continuous_three_tones(
        self, seg: List[Tuple[str, str]]
    ) -> List[Tuple[str, str]]:
        new_seg = []
        sub_finals_list = [
            lazy_pinyin(word, neutral_tone_with_five=True, style=Style.FINALS_TONE3)
            for (word, pos) in seg
        ]
        assert len(sub_finals_list) == len(seg)
        merge_last = [False] * len(seg)
        for i, (word, pos) in enumerate(seg):
            if (
                i - 1 >= 0
                and self._all_tone_three(sub_finals_list[i - 1])
                and self._all_tone_three(sub_finals_list[i])
                and not merge_last[i - 1]
            ):
                # if the last word is reduplication, not merge, because reduplication need to be _neural_sandhi
                if (
                    not self._is_reduplication(seg[i - 1][0])
                    and len(seg[i - 1][0]) + len(seg[i][0]) <= 3
                ):
                    new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
                    merge_last[i] = True
                else:
                    new_seg.append([word, pos])
            else:
                new_seg.append([word, pos])

        return new_seg

    def _is_reduplication(self, word: str) -> bool:
        return len(word) == 2 and word[0] == word[1]

    # the last char of first word and the first char of second word is tone_three
    def _merge_continuous_three_tones_2(
        self, seg: List[Tuple[str, str]]
    ) -> List[Tuple[str, str]]:
        new_seg = []
        sub_finals_list = [
            lazy_pinyin(word, neutral_tone_with_five=True, style=Style.FINALS_TONE3)
            for (word, pos) in seg
        ]
        assert len(sub_finals_list) == len(seg)
        merge_last = [False] * len(seg)
        for i, (word, pos) in enumerate(seg):
            if (
                i - 1 >= 0
                and sub_finals_list[i - 1][-1][-1] == "3"
                and sub_finals_list[i][0][-1] == "3"
                and not merge_last[i - 1]
            ):
                # if the last word is reduplication, not merge, because reduplication need to be _neural_sandhi
                if (
                    not self._is_reduplication(seg[i - 1][0])
                    and len(seg[i - 1][0]) + len(seg[i][0]) <= 3
                ):
                    new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
                    merge_last[i] = True
                else:
                    new_seg.append([word, pos])
            else:
                new_seg.append([word, pos])
        return new_seg

    def _merge_er(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = []
        for i, (word, pos) in enumerate(seg):
            if i - 1 >= 0 and word == "儿" and seg[i - 1][0] != "#":
                new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
            else:
                new_seg.append([word, pos])
        return new_seg

    def _merge_reduplication(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        new_seg = []
        for i, (word, pos) in enumerate(seg):
            if new_seg and word == new_seg[-1][0]:
                new_seg[-1][0] = new_seg[-1][0] + seg[i][0]
            else:
                new_seg.append([word, pos])
        return new_seg

    def pre_merge_for_modify(self, seg: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
        seg = self._merge_bu(seg)
        try:
            seg = self._merge_yi(seg)
        except:
            print("_merge_yi failed")
        seg = self._merge_reduplication(seg)
        seg = self._merge_continuous_three_tones(seg)
        seg = self._merge_continuous_three_tones_2(seg)
        seg = self._merge_er(seg)
        return seg

    def modified_tone(self, word: str, pos: str, finals: List[str]) -> List[str]:
        finals = self._bu_sandhi(word, finals)
        finals = self._yi_sandhi(word, finals)
        finals = self._neural_sandhi(word, pos, finals)
        finals = self._three_sandhi(word, finals)
        return finals