# -*- coding:utf-8 -*-

import os
import jieba

# 待处理的数据文件
DATA_KEYWORD_FILE = "E:\Download\怎么长尾词_1655561719.csv"

# 输出的结果文件
CUT_OUTPUT_FILE = "./data/分词与词频统计结果.csv"

# 文件编码格式
ENCODING_CHARSET = "UTF-8"

# 停用词
STOP_WORD_DIR = "./data/stopwords"

# 间隔进度提示
INTERNAL_NUM = 50000

def cut_word_and_statistics(data):

    """
    分词并统计词频
    """

    print("开始执行分词操作并进行词频统计")

    total_num = len(data)
    print("共需处理数据：%d" % total_num)

    # 分词结果容器
    key_dict = {}

    # 跳过开头两行
    for i, item in enumerate(data):
        # 只需要第一列的数据
        longTailKey = item.split(",")[0]

        longTailKey = longTailKey.replace("\n", "")
        
        # 分词
        cutWord = jieba.cut_for_search(longTailKey)

        # 统计
        for word in cutWord:
            if word in key_dict:
                key_dict[word] = key_dict[word] + 1
            else:
                key_dict[word] = 1
        
        # 进度提示
        if i % INTERNAL_NUM == 0:
            print("当前分词进度 %d / %d" % (i, total_num))

    print("根据词频进行倒序排列")

    # 根据词频倒序排列
    sorted_key_dict = sorted(key_dict.items(), key=lambda x: x[1], reverse=True)

    print("分词结束")

    return sorted_key_dict


def load_stop_words():
    """
    加载停用词列表
    """
    
    print("加载停用词 - 开始")

    # 停用词容器
    stop_word = []

    stop_word_files = os.listdir(STOP_WORD_DIR)

    for file in stop_word_files:
        stop_word_file = os.path.join(STOP_WORD_DIR, file)
        with open(stop_word_file, encoding=ENCODING_CHARSET) as f:
            for item in f:
                stop_word.append(item.replace("\n",""))

    print("去重前，停用词数量：", len(stop_word))

    stop_word = list(set(stop_word))

    print("去重后，停用词数量：", len(stop_word))

    print("加载停用词 - 结束")

    return stop_word


def filter_stop_word(word_root: dict) :
    """
    对分词结果过滤停用词
    """

    print("过滤停用词 - 开始")

    # 加载停用词
    stop_word = load_stop_words()
    
    print("过滤前，总分词数量：%d" % len(word_root))

    # 过滤停用词
    word_root_filter = dict((key, value) for key , value in word_root if key not in stop_word)

    print("过滤后，总分词数量：%d" % len(word_root_filter))

    print("过滤停用词 - 结束")

    return word_root_filter

def main():

    print("开始")

    if not os.path.exists(DATA_KEYWORD_FILE):
        raise Exception("待处理的数据文件不存在：%s" % DATA_KEYWORD_FILE)

    # 读取数据
    print("从待处理的数据文件中读取数据")
    lines = None
    with open(DATA_KEYWORD_FILE, "r", encoding=ENCODING_CHARSET) as f:
        lines = f.readlines()
    
    # 执行分词和词频统计
    word_root = cut_word_and_statistics(lines[:100])

    # 过滤停用词
    word_root_filter = filter_stop_word(word_root)
        
    # 导出过滤后的数据，不要表头和行号
    # print("导出过滤后的结果")
    # word_root_dataframe.to_csv(CUT_OUTPUT_FILE, header=False, index=False)
    with open(CUT_OUTPUT_FILE, "w", encoding=ENCODING_CHARSET) as f:
        for item in word_root_filter.items():
            f.write("%s,%d\n" % item)

    print("结束")


if __name__ == '__main__':
    main()