import json,re,os,Levenshtein

def load_dict(filename): #根据filename读取json数据库并转化为python字典
    with open(filename,"r",encoding = "u8") as f:
        adict = json.loads(f.read())
    return adict #返回python字典

def save_dict(adict,filename): #将adict字典转化为json文件并保存至filename文件中
    try:
        with open(filename,"w",encoding = "u8") as f:
            f.write(json.dumps(adict,indent=4,ensure_ascii=False))
        return 0 #成功则返回0
    except:
        return 1 #不成功则返回1


def pre_treating(string): #删除字符串中对比较无用的字符, 以供比较
    string = re.sub(r"\\begin\{center\}[\s\S]*?\\end\{center\}","",string)
    string = re.sub(r"(bracket\{\d+\})|(blank\{\d+\})|(fourch)|(twoch)|(onech)","",string)
    string = re.sub(r"[\s\\\{\}\$\(\)\[\]]","",string)
    string = re.sub(r"[\n\t]","",string)
    string = re.sub(r"(displaystyle)|(overrightarrow)|(overline)","",string)
    string = re.sub(r"[,\.:;?]","",string)
    return string #返回处理后的字符串

def treat_dict(p_dict): #对整个题库字典中的内容部分进行预处理，删除无用字符
    treated_dict = {}
    for id in p_dict:
        treated_dict[id] = {}
        treated_dict[id]["content"] = pre_treating(p_dict[id]["content"])
        treated_dict[id]["same"] = p_dict[id]["same"]
    return treated_dict #返回处理后的字典, 含内容字段及相同题目字段

def detectmaxsim(currentid,excludelist,adict): #检测与已知题目关联程度最大的题目（除外列表之外的部分）
    maxsim = -1
    argmaxsim = "000000"
    for id in adict:
        if not id in excludelist:
            simrate = Levenshtein.jaro(adict[id]["content"],adict[currentid]["content"])
            if simrate > maxsim:
                maxsim = simrate
                argmaxsim = id
    return (maxsim,argmaxsim) #返回最大关联系数与关联程度最大的题号

def generate_problem_series(startingid,length,adict): #在adict字典里返回从startingid开始的一系列题号, 每一题都是与上一题的关联程度最大的
    excludelist = [startingid]
    currentid = startingid
    for i in range(length):
        maxsim,currentid = detectmaxsim(currentid,excludelist,adict)
        excludelist.append(currentid)
    return ",".join(excludelist) #返回按顺序的题号列表



if __name__ == "__main__":
    print("数据库工具, import用.")