import re
import gzip
from crypt import *


class Backup:
    key = None
    compressMinSize = "50M"
    save_location = None

    def __init__(self, key):
        self.key = key

    def recurse(self, path):
        min_size = parse_size(self.compressMinSize)
        for f in os.listdir(path):
            uri = os.path.join(path, f)
            if os.path.isfile(uri):
                size = os.path.getsize(uri)
                print(f + " : ", human_size(size))
                if size > min_size:
                    enc = crypt(compress(uri), self.key)
                else:
                    enc = crypt(uri, self.key)
                save(enc, os.path.join(self.save_location, f + ".enc"))
            elif os.path.isdir(uri):
                self.recurse(uri)


def compress(file):
    if type(file) is str:
        infile = open(file, 'rb')
    elif type(file) is io.BufferedRandom or tempfile.SpooledTemporaryFile:
        file.seek(0)
        infile = file

    compressed_file = tempfile.SpooledTemporaryFile()
    with gzip.open(compressed_file, 'wb') as zipfile:
        while chunk := infile.read(64 * 1024):
            zipfile.write(chunk)
    return compressed_file


def uncompress(file):
    if type(file) is io.BufferedRandom or tempfile.SpooledTemporaryFile:
        file.seek(0)

    decompressed_file = tempfile.SpooledTemporaryFile()
    with gzip.open(file, 'rb') as zipfile:
        while chunk := zipfile.read(64 * 1024):
            decompressed_file.write(chunk)
    return decompressed_file


def crypt(file, key):
    encrypted_file = tempfile.SpooledTemporaryFile()
    encrypt_file(key, file, encrypted_file)
    return encrypted_file


def uncrypt(file, key):
    decrypted_file = tempfile.SpooledTemporaryFile()
    decrypt_file(key, file, decrypted_file)
    return decrypted_file


def save(file, name):
    if type(file) is io.BufferedRandom or tempfile.SpooledTemporaryFile:
        file.seek(0)
        with open(name, 'wb') as save:
            while chunk := file.read(64 * 1024):
                save.write(chunk)
    else:
        print("Unable to save " + str(file) + " of type " + str(type(file)))
        return


def human_size(size, decimal_places=0):
    for unit in ['B', 'K', 'M', 'G', 'T']:
        if size < 1024.0:
            break
        size /= 1024.0
    return f"{size:.{decimal_places}f}{unit}"


def parse_size(size):
    units = {"B": 1, "K": 2**10, "M": 2**20, "G": 2**30, "T": 2**40}
    if size[-1].isdigit():
        size = size + 'K'
    number, unit = re.match(r"([0-9]+)([BKMGT])", size, re.I).groups()
    return int(float(number)*units[unit])