python版的安卓base64

# -*- coding: utf-8 -*-
# @Author  : __LittleQ__
# @FileName: android_base64.py
import base64

DEFAULT = 0  # 默认模式, 每行不超过76个字符
NO_PADDING = 1  # 移除最后的=
NO_WRAP = 2  # 不换行，一行输出
CRLF = 4  # 采用win上的换行符
URL_SAVE = 8  # 采用urlsafe


def decode(content: str, flag: int) -> bytes:
    missing_padding = len(content) % 4
    if missing_padding != 0:
        content = content.ljust(len(content) + (4 - missing_padding), "=")

    if flag & URL_SAVE:
        result = base64.urlsafe_b64decode(content.encode("utf-8"))
    else:
        result = base64.b64decode(content.encode("utf-8"))
    return result


def encode(content: bytes, flag: int) -> str:
    need_wrap = True
    need_padding = True
    lf = "\n"

    if flag & NO_WRAP:
        need_wrap = False
    if flag & NO_PADDING:
        need_padding = False
    if flag & CRLF:
        lf = "\r\n"

    if flag & URL_SAVE:
        result = base64.urlsafe_b64encode(content).decode("utf-8")
    else:
        result = base64.b64encode(content).decode("utf-8")

    if not need_padding:
        result = result.rstrip("=")

    if need_wrap:
        n = 76
        output = lf.join([result[i:i + n] for i in range(0, len(result), n)])
    else:
        output = result

    return output