name_list = []
tmp_list = []
info_list = []
f = open("homeworkdb","r",encoding="utf-8")
for line in f:
    if line.startswith("backend"):
        tmp_list = (line.strip().split(" "))
        # name_list.append(tmp_list[1])
        # print(tmp_list)
        name_list.append(tmp_list[1])

f.close()
flag = 0
# print(name_list)
while True:
    option = int(input("1:查询用户信息\n2:删除用户信息\n3:增加用户信息\n4:退出\n"))
    if option == 1:
        name = input("please input name:")
        if name in name_list:
            with open("homeworkdb","r",encoding="utf-8") as f:
                for line in f:
                    if flag == 0 and line.strip() == "backend " + name:
                        flag = 1
                        continue
                    if flag == 1 and not line.startswith("backend"):
                        info_list.append(line.strip())
                    if flag == 1 and line.startswith("backend"):
                        flag = 0
                        continue
                print("%s的信息是：" %(name))
                for info in info_list:
                    print(info)
                info_list = []
        else:
            print("%s is not in list" %(name))
            continue
    elif option == 2:
        name = input("please in name:")
        if name in name_list:
            with open("homeworkdb","r",encoding="utf-8") as f1,open("tmp","w",encoding="utf-8") as f2:
                for line in f1:
                    if flag == 0 and line.strip() == "backend " + name:
                        flag = 1
                        continue
                    if flag == 1 and not line.startswith("backend"):
                        continue
                    if flag == 1 and line.startswith("backend"):
                        flag = 0
                    if flag == 0:
                        f2.write(line)
            with open("homeworkdb","w",encoding="utf-8") as f1,open("tmp","r",encoding="utf-8") as f2:
                for line in f2:
                    f1.write(line)
            name_list.remove(name)
            with open("homeworkdb","r",encoding="utf-8") as f1,open("tmp","w",encoding="utf-8") as f2:
                for line in f1:
                    if line == "\n":
                        continue
                    else:
                        f2.write(line)

            with open("tmp","r",encoding="utf-8") as f1,open("homeworkdb","w",encoding="utf-8") as f2:
                for line in f1:
                    f2.write(line)
        else:
            print("%s is not in list" %(name))
            continue
    elif option == 3:
        name = input("please in name:")
        if name in name_list:
            print("%s is in list" % (name))
            info = input("please input %s is information" % (name))
            with open("homeworkdb" ,"r",encoding="utf-8") as f1:
                for line in f1:
                    if flag == 0 and line.strip() == "backend " + name:
                        flag = 1
                        continue
                    if flag == 1 and not line.startswith("backend"):
                        info_list.append(line)
                    if flag == 1 and line.startswith("backend"):
                        flag = 0
                        continue
            if info in tmp_list:
                print("%s is already exist" %(info ))
            else:
                with open("homeworkdb","r",encoding="utf-8") as f1,open("tmp","w",encoding="utf-8") as f2:
                    flag = 0
                    for line in f1:
                        # print(flag)
                        if flag == 0 and line.strip() == "backend " + name:
                            f2.write(line)
                            tmp_info ="     " + info + "\n"
                            f2.write(tmp_info)
                        else:
                            f2.write(line)
                with open("tmp","r",encoding="utf-8") as f1,open("homeworkdb","w",encoding="utf-8") as f2:
                    for line in f1:
                        f2.write(line)
        else:
            print("%s is not in list" %(name))
            info = input("please input %s is information" % (name))
            with open("homeworkdb","a",encoding="utf-8") as f1:
                s1 = "\n" + "backend " + name
                s2 = "\n" + "     " + info
                f1.write(s1)
                f1.write(s2)
                name_list.append(name)
    elif option == 4:
        exit()
    else:
        print("invalid input,please input[1|2|3|4]")
        continue