import json
import re


class FunctionUtil:
    def __init__(self):
        self.filename = "./function.json"
        self.data = {}
        self.load()

    def load(self):
        """
        加载文件数据
        """
        try:
            with open(self.filename, 'r', encoding="utf-8") as f:
                self.data = json.load(f)
        except FileNotFoundError:
            pass

    def save(self):
        """
        将函数保存至json文件当中
        """
        with open(self.filename, "w", encoding="utf-8") as f:
            json.dump(self.data, f)

    def check_function_exit(self, function):
        """
        检查用户输入的函数是否包含用户自定义函数
        """
        for key in self.data.keys():
            if function.find(key) >=0:
                return True
        return False

    def add_function(self, key, value):
        """
        添加函数
        """
        self.data[key.strip()] = value.strip()
        self.save()

    def get_function_by_iter(self, key):
        result = key
        for dict_key in self.data.keys():
            if result.find(dict_key) >= 0:
                value = result.replace(dict_key, self.data[dict_key])
                result = self.replace_values_recursive(value)
        return result

    def replace_values_recursive(self, value):
        for key in self.data:
            if key in value:
                replacement = self.data[key]
                value = value.replace(key, replacement)
        return value