import hashlib
import os
import sys
import urllib.request
from pathlib import Path

from bulkredditdownloader.errors import DomainInSkip, FailedToDownload, FileAlreadyExistsError, TypeInSkip
from bulkredditdownloader.utils import GLOBAL
from bulkredditdownloader.utils import printToFile as print


def dlProgress(count: int, block_size: int, total_size: int):
    """Function for writing download progress to console
    """
    download_mbs = int(count * block_size * (10 ** (-6)))
    file_size = int(total_size * (10 ** (-6)))
    sys.stdout.write("{}Mb/{}Mb\r".format(download_mbs, file_size))
    sys.stdout.flush()


def getExtension(link: str):
    """Extract file extension from image link.
    If didn't find any, return '.jpg'
    """
    image_types = ['jpg', 'png', 'mp4', 'webm', 'gif']
    parsed = link.split('.')
    for fileType in image_types:
        if fileType in parsed:
            return "." + parsed[-1]
    else:
        if "v.redd.it" not in link:
            return '.jpg'
        else:
            return '.mp4'


def getFile(filename: str, short_filename: str, folder_dir: Path, image_url: str, indent: int = 0, silent: bool = False):
    formats = {
        "videos": [".mp4", ".webm"],
        "images": [".jpg", ".jpeg", ".png", ".bmp"],
        "gifs": [".gif"],
        "self": []
    }

    for file_type in GLOBAL.arguments.skip:
        for extension in formats[file_type]:
            if extension in filename:
                raise TypeInSkip

    if any(domain in image_url for domain in GLOBAL.arguments.skip_domain):
        raise DomainInSkip

    headers = [
        ("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
            "AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 "
            "Safari/537.36 OPR/54.0.2952.64"),
        ("Accept", "text/html,application/xhtml+xml,application/xml;"
            "q=0.9,image/webp,image/apng,*/*;q=0.8"),
        ("Accept-Charset", "ISO-8859-1,utf-8;q=0.7,*;q=0.3"),
        ("Accept-Encoding", "none"),
        ("Accept-Language", "en-US,en;q=0.8"),
        ("Connection", "keep-alive")
    ]

    if not os.path.exists(folder_dir):
        os.makedirs(folder_dir)

    opener = urllib.request.build_opener()
    if "imgur" not in image_url:
        opener.addheaders = headers
    urllib.request.install_opener(opener)

    if not silent:
        print(" " * indent + str(folder_dir), " " * indent + str(filename), sep="\n")

    for i in range(3):
        file_dir = Path(folder_dir) / filename
        temp_dir = Path(folder_dir) / (filename + ".tmp")

        if not (os.path.isfile(file_dir)):
            try:
                urllib.request.urlretrieve(image_url, temp_dir, reporthook=dlProgress)

                file_hash = createHash(temp_dir)
                if GLOBAL.arguments.no_dupes:
                    if file_hash in GLOBAL.downloadedPosts():
                        os.remove(temp_dir)
                        raise FileAlreadyExistsError
                GLOBAL.downloadedPosts.add(file_hash)

                os.rename(temp_dir, file_dir)
                if not silent:
                    print(" " * indent + "Downloaded" + " " * 10)
                return None
            except ConnectionResetError:
                raise FailedToDownload
            except FileNotFoundError:
                filename = short_filename
        else:
            raise FileAlreadyExistsError
    raise FailedToDownload


def createHash(filename: str) -> str:
    hash_md5 = hashlib.md5()
    with open(filename, "rb") as f:
        for chunk in iter(lambda: f.read(4096), b""):
            hash_md5.update(chunk)
    return hash_md5.hexdigest()