# _*_ coding: utf-8 _*_
# @Time : 2021/5/27 14:58
# @File : funcs.py
# @Software: PyCharm

"""
此文件存放一些公用的工具函数
"""
import datetime
import random
from random import shuffle
from django_redis import get_redis_connection

from utils.custom import MyCustomError


def generate_random_str(randomlength=16):
    """
    生成一个指定长度的随机字符串
    """
    random_str = ''
    base_str = 'abcdefghigklmnopqrstuvwxyz0123456789'
    length = len(base_str) - 1
    for i in range(randomlength):
        random_str += base_str[random.randint(0, length)]
    return random_str


def generate_random_str_16_system(randomlength=16):
    """
    生成一个指定长度的随机字符串, 这个字符串看起来像16进制的
    """
    random_str = ''
    base_str = '0123456789abcdef'
    length = len(base_str) - 1
    for i in range(randomlength):
        random_str += base_str[random.randint(0, length)]
    return random_str


# 获取乱序字符串
def shuffle_str(s):
    # 将字符串转换成列表
    str_list = list(s)
    # 调用random模块的shuffle函数打乱列表
    shuffle(str_list)
    # 将列表转字符串
    return ''.join(str_list)


# 获取原来字符串在新字符串中的位置
def str_map(origin, new_str):
    result_str = []
    new_str_list = list(new_str)
    for each in origin:
        index = new_str_list.index(each)
        result_str.append(index)
    # 生成轨迹
    track = random.sample(range(0, len(result_str)), len(result_str))
    return result_str, track


# 定义尝试的日期格式列表
sys_formats = ["%Y-%m-%d", "%Y/%m/%d", "%Y年%m月%d日", "%Y%m%d"]


def parse_date(date_string, formats=sys_formats):
    """
    尝试按照提供的格式解析日期字符串， 返回日期date
    @param date_string: 日期字符串
    @param formats: 尝试格式
    @return:
    """
    if not isinstance(formats, list):
        if not isinstance(formats, str) or formats not in sys_formats:
            raise MyCustomError("日期格式不支持")
        formats = [formats, ]
    for fmt in formats:
        try:
            return datetime.datetime.strptime(date_string, fmt).date()
        except ValueError:
            pass
    raise MyCustomError("无法解析日期字符串")