#!/usr/bin/env python

import io
import os
import re
import sys
import time
import json
import socket
import locale
import logging
import argparse
from http import cookiejar
from importlib import import_module
from urllib import request, parse, error

from .version import __version__
from .util import log, term
from .util.git import get_version
from .util.strings import get_filename, unescape_html
from . import json_output as json_output_
sys.stdout = io.TextIOWrapper(sys.stdout.buffer,encoding='utf8')

SITES = {
    '163'              : 'netease',
    '56'               : 'w56',
    '365yg'            : 'toutiao',
    'acfun'            : 'acfun',
    'archive'          : 'archive',
    'baidu'            : 'baidu',
    'bandcamp'         : 'bandcamp',
    'baomihua'         : 'baomihua',
    'bigthink'         : 'bigthink',
    'bilibili'         : 'bilibili',
    'cctv'             : 'cntv',
    'cntv'             : 'cntv',
    'cbs'              : 'cbs',
    'coub'             : 'coub',
    'dailymotion'      : 'dailymotion',
    'dilidili'         : 'dilidili',
    'douban'           : 'douban',
    'douyin'           : 'douyin',
    'douyu'            : 'douyutv',
    'ehow'             : 'ehow',
    'facebook'         : 'facebook',
    'fantasy'          : 'fantasy',
    'fc2'              : 'fc2video',
    'flickr'           : 'flickr',
    'freesound'        : 'freesound',
    'fun'              : 'funshion',
    'google'           : 'google',
    'giphy'            : 'giphy',
    'heavy-music'      : 'heavymusic',
    'huaban'           : 'huaban',
    'huomao'           : 'huomaotv',
    'iask'             : 'sina',
    'icourses'         : 'icourses',
    'ifeng'            : 'ifeng',
    'imgur'            : 'imgur',
    'in'               : 'alive',
    'infoq'            : 'infoq',
    'instagram'        : 'instagram',
    'interest'         : 'interest',
    'iqilu'            : 'iqilu',
    'iqiyi'            : 'iqiyi',
    'ixigua'           : 'ixigua',
    'isuntv'           : 'suntv',
    'iwara'            : 'iwara',
    'joy'              : 'joy',
    'kankanews'        : 'bilibili',
    'khanacademy'      : 'khan',
    'ku6'              : 'ku6',
    'kuaishou'         : 'kuaishou',
    'kugou'            : 'kugou',
    'kuwo'             : 'kuwo',
    'le'               : 'le',
    'letv'             : 'le',
    'lizhi'            : 'lizhi',
    'longzhu'          : 'longzhu',
    'magisto'          : 'magisto',
    'metacafe'         : 'metacafe',
    'mgtv'             : 'mgtv',
    'miomio'           : 'miomio',
    'mixcloud'         : 'mixcloud',
    'mtv81'            : 'mtv81',
    'musicplayon'      : 'musicplayon',
    'miaopai'          : 'yixia',
    'naver'            : 'naver',
    '7gogo'            : 'nanagogo',
    'nicovideo'        : 'nicovideo',
    'panda'            : 'panda',
    'pinterest'        : 'pinterest',
    'pixnet'           : 'pixnet',
    'pptv'             : 'pptv',
    'qingting'         : 'qingting',
    'qq'               : 'qq',
    'quanmin'          : 'quanmin',
    'showroom-live'    : 'showroom',
    'sina'             : 'sina',
    'smgbb'            : 'bilibili',
    'sohu'             : 'sohu',
    'soundcloud'       : 'soundcloud',
    'ted'              : 'ted',
    'theplatform'      : 'theplatform',
    'tiktok'           : 'tiktok',
    'tucao'            : 'tucao',
    'tudou'            : 'tudou',
    'tumblr'           : 'tumblr',
    'twimg'            : 'twitter',
    'twitter'          : 'twitter',
    'ucas'             : 'ucas',
    'videomega'        : 'videomega',
    'vidto'            : 'vidto',
    'vimeo'            : 'vimeo',
    'wanmen'           : 'wanmen',
    'weibo'            : 'miaopai',
    'veoh'             : 'veoh',
    'vine'             : 'vine',
    'vk'               : 'vk',
    'xiami'            : 'xiami',
    'xiaokaxiu'        : 'yixia',
    'xiaojiadianvideo' : 'fc2video',
    'ximalaya'         : 'ximalaya',
    'yinyuetai'        : 'yinyuetai',
    'yizhibo'          : 'yizhibo',
    'youku'            : 'youku',
    'youtu'            : 'youtube',
    'youtube'          : 'youtube',
    'zhanqi'           : 'zhanqi',
    'zhibo'            : 'zhibo',
    'zhihu'            : 'zhihu',
}

dry_run = False
json_output = False
force = False
player = None
extractor_proxy = None
cookies = None
output_filename = None
auto_rename = False

fake_headers = {
    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',  # noqa
    'Accept-Charset': 'UTF-8,*;q=0.5',
    'Accept-Encoding': 'gzip,deflate,sdch',
    'Accept-Language': 'en-US,en;q=0.8',
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Firefox/60.0',  # noqa
}

if sys.stdout.isatty():
    default_encoding = sys.stdout.encoding.lower()
else:
    default_encoding = locale.getpreferredencoding().lower()


def rc4(key, data):
    # all encryption algo should work on bytes
    assert type(key) == type(data) and type(key) == type(b'')
    state = list(range(256))
    j = 0
    for i in range(256):
        j += state[i] + key[i % len(key)]
        j &= 0xff
        state[i], state[j] = state[j], state[i]

    i = 0
    j = 0
    out_list = []
    for char in data:
        i += 1
        i &= 0xff
        j += state[i]
        j &= 0xff
        state[i], state[j] = state[j], state[i]
        prn = state[(state[i] + state[j]) & 0xff]
        out_list.append(char ^ prn)

    return bytes(out_list)


def general_m3u8_extractor(url, headers={}):
    m3u8_list = get_content(url, headers=headers).split('\n')
    urls = []
    for line in m3u8_list:
        line = line.strip()
        if line and not line.startswith('#'):
            if line.startswith('http'):
                urls.append(line)
            else:
                seg_url = parse.urljoin(url, line)
                urls.append(seg_url)
    return urls


def maybe_print(*s):
    try:
        print(*s)
    except:
        pass


def tr(s):
    if default_encoding == 'utf-8':
        return s
    else:
        return s
        # return str(s.encode('utf-8'))[2:-1]


# DEPRECATED in favor of match1()
def r1(pattern, text):
    m = re.search(pattern, text)
    if m:
        return m.group(1)


# DEPRECATED in favor of match1()
def r1_of(patterns, text):
    for p in patterns:
        x = r1(p, text)
        if x:
            return x


def match1(text, *patterns):
    """Scans through a string for substrings matched some patterns (first-subgroups only).

    Args:
        text: A string to be scanned.
        patterns: Arbitrary number of regex patterns.

    Returns:
        When only one pattern is given, returns a string (None if no match found).
        When more than one pattern are given, returns a list of strings ([] if no match found).
    """

    if len(patterns) == 1:
        pattern = patterns[0]
        match = re.search(pattern, text)
        if match:
            return match.group(1)
        else:
            return None
    else:
        ret = []
        for pattern in patterns:
            match = re.search(pattern, text)
            if match:
                ret.append(match.group(1))
        return ret


def matchall(text, patterns):
    """Scans through a string for substrings matched some patterns.

    Args:
        text: A string to be scanned.
        patterns: a list of regex pattern.

    Returns:
        a list if matched. empty if not.
    """

    ret = []
    for pattern in patterns:
        match = re.findall(pattern, text)
        ret += match

    return ret


def launch_player(player, urls):
    import subprocess
    import shlex
    import shutil
    exefile=shlex.split(player)[0]
    if shutil.which(exefile) is not None:
        subprocess.call(shlex.split(player) + list(urls))
    else:
        log.wtf('[Failed] Cannot find player "%s"' % exefile)


def parse_query_param(url, param):
    """Parses the query string of a URL and returns the value of a parameter.

    Args:
        url: A URL.
        param: A string representing the name of the parameter.

    Returns:
        The value of the parameter.
    """

    try:
        return parse.parse_qs(parse.urlparse(url).query)[param][0]
    except:
        return None


def unicodize(text):
    return re.sub(
        r'\\u([0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f])',
        lambda x: chr(int(x.group(0)[2:], 16)),
        text
    )


# DEPRECATED in favor of util.legitimize()
def escape_file_path(path):
    path = path.replace('/', '-')
    path = path.replace('\\', '-')
    path = path.replace('*', '-')
    path = path.replace('?', '-')
    return path


def ungzip(data):
    """Decompresses data for Content-Encoding: gzip.
    """
    from io import BytesIO
    import gzip
    buffer = BytesIO(data)
    f = gzip.GzipFile(fileobj=buffer)
    return f.read()


def undeflate(data):
    """Decompresses data for Content-Encoding: deflate.
    (the zlib compression is used.)
    """
    import zlib
    decompressobj = zlib.decompressobj(-zlib.MAX_WBITS)
    return decompressobj.decompress(data)+decompressobj.flush()


# DEPRECATED in favor of get_content()
def get_response(url, faker=False):
    logging.debug('get_response: %s' % url)

    # install cookies
    if cookies:
        opener = request.build_opener(request.HTTPCookieProcessor(cookies))
        request.install_opener(opener)

    if faker:
        response = request.urlopen(
            request.Request(url, headers=fake_headers), None
        )
    else:
        response = request.urlopen(url)

    data = response.read()
    if response.info().get('Content-Encoding') == 'gzip':
        data = ungzip(data)
    elif response.info().get('Content-Encoding') == 'deflate':
        data = undeflate(data)
    response.data = data
    return response


# DEPRECATED in favor of get_content()
def get_html(url, encoding=None, faker=False):
    content = get_response(url, faker).data
    return str(content, 'utf-8', 'ignore')


# DEPRECATED in favor of get_content()
def get_decoded_html(url, faker=False):
    response = get_response(url, faker)
    data = response.data
    charset = r1(r'charset=([\w-]+)', response.headers['content-type'])
    if charset:
        return data.decode(charset, 'ignore')
    else:
        return data


def get_location(url, headers=None, get_method='HEAD'):
    logging.debug('get_location: %s' % url)

    if headers:
        req = request.Request(url, headers=headers)
    else:
        req = request.Request(url)
    req.get_method = lambda: get_method
    res = urlopen_with_retry(req)
    return res.geturl()


def urlopen_with_retry(*args, **kwargs):
    retry_time = 3
    for i in range(retry_time):
        try:
            return request.urlopen(*args, **kwargs)
        except socket.timeout as e:
            logging.debug('request attempt %s timeout' % str(i + 1))
            if i + 1 == retry_time:
                raise e
        # try to tackle youku CDN fails
        except error.HTTPError as http_error:
            logging.debug('HTTP Error with code{}'.format(http_error.code))
            if i + 1 == retry_time:
                raise http_error


def get_content(url, headers={}, decoded=True):
    """Gets the content of a URL via sending a HTTP GET request.

    Args:
        url: A URL.
        headers: Request headers used by the client.
        decoded: Whether decode the response body using UTF-8 or the charset specified in Content-Type.

    Returns:
        The content as a string.
    """

    logging.debug('get_content: %s' % url)

    req = request.Request(url, headers=headers)
    if cookies:
        cookies.add_cookie_header(req)
        req.headers.update(req.unredirected_hdrs)

    response = urlopen_with_retry(req)
    data = response.read()

    # Handle HTTP compression for gzip and deflate (zlib)
    content_encoding = response.getheader('Content-Encoding')
    if content_encoding == 'gzip':
        data = ungzip(data)
    elif content_encoding == 'deflate':
        data = undeflate(data)

    # Decode the response body
    if decoded:
        charset = match1(
            response.getheader('Content-Type', ''), r'charset=([\w-]+)'
        )
        if charset is not None:
            data = data.decode(charset)
        else:
            data = data.decode('utf-8', 'ignore')

    return data


def post_content(url, headers={}, post_data={}, decoded=True, **kwargs):
    """Post the content of a URL via sending a HTTP POST request.

    Args:
        url: A URL.
        headers: Request headers used by the client.
        decoded: Whether decode the response body using UTF-8 or the charset specified in Content-Type.

    Returns:
        The content as a string.
    """
    if kwargs.get('post_data_raw'):
        logging.debug('post_content: %s\npost_data_raw: %s' % (url, kwargs['post_data_raw']))
    else:
        logging.debug('post_content: %s\npost_data: %s' % (url, post_data))

    req = request.Request(url, headers=headers)
    if cookies:
        cookies.add_cookie_header(req)
        req.headers.update(req.unredirected_hdrs)
    if kwargs.get('post_data_raw'):
        post_data_enc = bytes(kwargs['post_data_raw'], 'utf-8')
    else:
        post_data_enc = bytes(parse.urlencode(post_data), 'utf-8')
    response = urlopen_with_retry(req, data=post_data_enc)
    data = response.read()

    # Handle HTTP compression for gzip and deflate (zlib)
    content_encoding = response.getheader('Content-Encoding')
    if content_encoding == 'gzip':
        data = ungzip(data)
    elif content_encoding == 'deflate':
        data = undeflate(data)

    # Decode the response body
    if decoded:
        charset = match1(
            response.getheader('Content-Type'), r'charset=([\w-]+)'
        )
        if charset is not None:
            data = data.decode(charset)
        else:
            data = data.decode('utf-8')

    return data


def url_size(url, faker=False, headers={}):
    if faker:
        response = urlopen_with_retry(
            request.Request(url, headers=fake_headers)
        )
    elif headers:
        response = urlopen_with_retry(request.Request(url, headers=headers))
    else:
        response = urlopen_with_retry(url)

    size = response.headers['content-length']
    return int(size) if size is not None else float('inf')


def urls_size(urls, faker=False, headers={}):
    return sum([url_size(url, faker=faker, headers=headers) for url in urls])


def get_head(url, headers=None, get_method='HEAD'):
    logging.debug('get_head: %s' % url)

    if headers:
        req = request.Request(url, headers=headers)
    else:
        req = request.Request(url)
    req.get_method = lambda: get_method
    res = urlopen_with_retry(req)
    return res.headers


def url_info(url, faker=False, headers={}):
    logging.debug('url_info: %s' % url)

    if faker:
        response = urlopen_with_retry(
            request.Request(url, headers=fake_headers)
        )
    elif headers:
        response = urlopen_with_retry(request.Request(url, headers=headers))
    else:
        response = urlopen_with_retry(request.Request(url))

    headers = response.headers

    type = headers['content-type']
    if type == 'image/jpg; charset=UTF-8' or type == 'image/jpg':
        type = 'audio/mpeg'  # fix for netease
    mapping = {
        'video/3gpp': '3gp',
        'video/f4v': 'flv',
        'video/mp4': 'mp4',
        'video/MP2T': 'ts',
        'video/quicktime': 'mov',
        'video/webm': 'webm',
        'video/x-flv': 'flv',
        'video/x-ms-asf': 'asf',
        'audio/mp4': 'mp4',
        'audio/mpeg': 'mp3',
        'audio/wav': 'wav',
        'audio/x-wav': 'wav',
        'audio/wave': 'wav',
        'image/jpeg': 'jpg',
        'image/png': 'png',
        'image/gif': 'gif',
        'application/pdf': 'pdf',
    }
    if type in mapping:
        ext = mapping[type]
    else:
        type = None
        if headers['content-disposition']:
            try:
                filename = parse.unquote(
                    r1(r'filename="?([^"]+)"?', headers['content-disposition'])
                )
                if len(filename.split('.')) > 1:
                    ext = filename.split('.')[-1]
                else:
                    ext = None
            except:
                ext = None
        else:
            ext = None

    if headers['transfer-encoding'] != 'chunked':
        size = headers['content-length'] and int(headers['content-length'])
    else:
        size = None

    return type, ext, size


def url_locations(urls, faker=False, headers={}):
    locations = []
    for url in urls:
        logging.debug('url_locations: %s' % url)

        if faker:
            response = urlopen_with_retry(
                request.Request(url, headers=fake_headers)
            )
        elif headers:
            response = urlopen_with_retry(
                request.Request(url, headers=headers)
            )
        else:
            response = urlopen_with_retry(request.Request(url))

        locations.append(response.url)
    return locations


def url_save(
    url, filepath, bar, refer=None, is_part=False, faker=False,
    headers=None, timeout=None, **kwargs
):
    tmp_headers = headers.copy() if headers is not None else {}
    # When a referer specified with param refer,
    # the key must be 'Referer' for the hack here
    if refer is not None:
        tmp_headers['Referer'] = refer
    if type(url) is list:
        file_size = urls_size(url, faker=faker, headers=tmp_headers)
        is_chunked, urls = True, url
    else:
        file_size = url_size(url, faker=faker, headers=tmp_headers)
        is_chunked, urls = False, [url]

    continue_renameing = True
    while continue_renameing:
        continue_renameing = False
        if os.path.exists(filepath):
            if not force and file_size == os.path.getsize(filepath):
                if not is_part:
                    if bar:
                        bar.done()
                    log.w(
                        'Skipping {}: file already exists'.format(
                            tr(os.path.basename(filepath))
                        )
                    )
                else:
                    if bar:
                        bar.update_received(file_size)
                return
            else:
                if not is_part:
                    if bar:
                        bar.done()
                    if not force and auto_rename:
                        path, ext = os.path.basename(filepath).rsplit('.', 1)
                        finder = re.compile(' \([1-9]\d*?\)$')
                        if (finder.search(path) is None):
                            thisfile = path + ' (1).' + ext
                        else:
                            def numreturn(a):
                                return ' (' + str(int(a.group()[2:-1]) + 1) + ').'
                            thisfile = finder.sub(numreturn, path) + ext
                        filepath = os.path.join(os.path.dirname(filepath), thisfile)
                        print('Changing name to %s' % tr(os.path.basename(filepath)), '...')
                        continue_renameing = True
                        continue
                    if log.yes_or_no('File with this name already exists. Overwrite?'):
                        log.w('Overwriting %s ...' % tr(os.path.basename(filepath)))
                    else:
                        return
        elif not os.path.exists(os.path.dirname(filepath)):
            os.mkdir(os.path.dirname(filepath))

    temp_filepath = filepath + '.download' if file_size != float('inf') \
        else filepath
    received = 0
    if not force:
        open_mode = 'ab'

        if os.path.exists(temp_filepath):
            received += os.path.getsize(temp_filepath)
            if bar:
                bar.update_received(os.path.getsize(temp_filepath))
    else:
        open_mode = 'wb'

    for url in urls:
        received_chunk = 0
        if received < file_size:
            if faker:
                tmp_headers = fake_headers
            '''
            if parameter headers passed in, we have it copied as tmp_header
            elif headers:
                headers = headers
            else:
                headers = {}
            '''
            if received and not is_chunked:  # only request a range when not chunked
                tmp_headers['Range'] = 'bytes=' + str(received) + '-'
            if refer:
                tmp_headers['Referer'] = refer

            if timeout:
                response = urlopen_with_retry(
                    request.Request(url, headers=tmp_headers), timeout=timeout
                )
            else:
                response = urlopen_with_retry(
                    request.Request(url, headers=tmp_headers)
                )
            try:
                range_start = int(
                    response.headers[
                        'content-range'
                    ][6:].split('/')[0].split('-')[0]
                )
                end_length = int(
                    response.headers['content-range'][6:].split('/')[1]
                )
                range_length = end_length - range_start
            except:
                content_length = response.headers['content-length']
                range_length = int(content_length) if content_length is not None \
                    else float('inf')

            if is_chunked:  # always append if chunked
                open_mode = 'ab'
            elif file_size != received + range_length:  # is it ever necessary?
                received = 0
                if bar:
                    bar.received = 0
                open_mode = 'wb'

            with open(temp_filepath, open_mode) as output:
                while True:
                    buffer = None
                    try:
                        buffer = response.read(1024 * 256)
                    except socket.timeout:
                        pass
                    if not buffer:
                        if is_chunked and received_chunk == range_length:
                            break
                        elif not is_chunked and received == file_size:  # Download finished
                            break
                        # Unexpected termination. Retry request
                        if not is_chunked:  # when
                            tmp_headers['Range'] = 'bytes=' + str(received) + '-'
                        response = urlopen_with_retry(
                            request.Request(url, headers=tmp_headers)
                        )
                        continue
                    output.write(buffer)
                    received += len(buffer)
                    received_chunk += len(buffer)
                    if bar:
                        bar.update_received(len(buffer))

    assert received == os.path.getsize(temp_filepath), '%s == %s == %s' % (
        received, os.path.getsize(temp_filepath), temp_filepath
    )

    if os.access(filepath, os.W_OK):
        # on Windows rename could fail if destination filepath exists
        os.remove(filepath)
    os.rename(temp_filepath, filepath)


class SimpleProgressBar:
    term_size = term.get_terminal_size()[1]

    def __init__(self, total_size, total_pieces=1):
        self.displayed = False
        self.total_size = total_size
        self.total_pieces = total_pieces
        self.current_piece = 1
        self.received = 0
        self.speed = ''
        self.last_updated = time.time()

        total_pieces_len = len(str(total_pieces))
        # 38 is the size of all statically known size in self.bar
        total_str = '%5s' % round(self.total_size / 1048576, 1)
        total_str_width = max(len(total_str), 5)
        self.bar_size = self.term_size - 28 - 2 * total_pieces_len \
            - 2 * total_str_width
        self.bar = '{:>4}%% ({:>%s}/%sMB) ├{:─<%s}┤[{:>%s}/{:>%s}] {}' % (
            total_str_width, total_str, self.bar_size, total_pieces_len,
            total_pieces_len
        )

    def update(self):
        self.displayed = True
        bar_size = self.bar_size
        percent = round(self.received * 100 / self.total_size, 1)
        if percent >= 100:
            percent = 100
        dots = bar_size * int(percent) // 100
        plus = int(percent) - dots // bar_size * 100
        if plus > 0.8:
            plus = '█'
        elif plus > 0.4:
            plus = '>'
        else:
            plus = ''
        bar = '█' * dots + plus
        bar = self.bar.format(
            percent, round(self.received / 1048576, 1), bar,
            self.current_piece, self.total_pieces, self.speed
        )
        sys.stdout.write('\r' + bar)
        sys.stdout.flush()

    def update_received(self, n):
        self.received += n
        time_diff = time.time() - self.last_updated
        bytes_ps = n / time_diff if time_diff else 0
        if bytes_ps >= 1024 ** 3:
            self.speed = '{:4.0f} GB/s'.format(bytes_ps / 1024 ** 3)
        elif bytes_ps >= 1024 ** 2:
            self.speed = '{:4.0f} MB/s'.format(bytes_ps / 1024 ** 2)
        elif bytes_ps >= 1024:
            self.speed = '{:4.0f} kB/s'.format(bytes_ps / 1024)
        else:
            self.speed = '{:4.0f}  B/s'.format(bytes_ps)
        self.last_updated = time.time()
        self.update()

    def update_piece(self, n):
        self.current_piece = n

    def done(self):
        if self.displayed:
            print()
            self.displayed = False


class PiecesProgressBar:
    def __init__(self, total_size, total_pieces=1):
        self.displayed = False
        self.total_size = total_size
        self.total_pieces = total_pieces
        self.current_piece = 1
        self.received = 0

    def update(self):
        self.displayed = True
        bar = '{0:>5}%[{1:<40}] {2}/{3}'.format(
            '', '=' * 40, self.current_piece, self.total_pieces
        )
        sys.stdout.write('\r' + bar)
        sys.stdout.flush()

    def update_received(self, n):
        self.received += n
        self.update()

    def update_piece(self, n):
        self.current_piece = n

    def done(self):
        if self.displayed:
            print()
            self.displayed = False


class DummyProgressBar:
    def __init__(self, *args):
        pass

    def update_received(self, n):
        pass

    def update_piece(self, n):
        pass

    def done(self):
        pass


def get_output_filename(urls, title, ext, output_dir, merge):
    # lame hack for the --output-filename option
    global output_filename
    if output_filename:
        if ext:
            return output_filename + '.' + ext
        return output_filename

    merged_ext = ext
    if (len(urls) > 1) and merge:
        from .processor.ffmpeg import has_ffmpeg_installed
        if ext in ['flv', 'f4v']:
            if has_ffmpeg_installed():
                merged_ext = 'mp4'
            else:
                merged_ext = 'flv'
        elif ext == 'mp4':
            merged_ext = 'mp4'
        elif ext == 'ts':
            if has_ffmpeg_installed():
                merged_ext = 'mkv'
            else:
                merged_ext = 'ts'
    return '%s.%s' % (title, merged_ext)

def print_user_agent(faker=False):
    urllib_default_user_agent = 'Python-urllib/%d.%d' % sys.version_info[:2]
    user_agent = fake_headers['User-Agent'] if faker else urllib_default_user_agent
    print('User Agent: %s' % user_agent)

def download_urls(
    urls, title, ext, total_size, output_dir='.', refer=None, merge=True,
    faker=False, headers={}, **kwargs
):
    assert urls
    if json_output:
        json_output_.download_urls(
            urls=urls, title=title, ext=ext, total_size=total_size,
            refer=refer
        )
        return
    if dry_run:
        print_user_agent(faker=faker)
        print('Real URLs:\n%s' % '\n'.join(urls))
        return

    if player:
        launch_player(player, urls)
        return

    if not total_size:
        try:
            total_size = urls_size(urls, faker=faker, headers=headers)
        except:
            import traceback
            traceback.print_exc(file=sys.stdout)
            pass

    title = tr(get_filename(title))
    output_filename = get_output_filename(urls, title, ext, output_dir, merge)
    output_filepath = os.path.join(output_dir, output_filename)

    if total_size:
        if not force and os.path.exists(output_filepath) and not auto_rename\
                and os.path.getsize(output_filepath) >= total_size * 0.9:
            log.w('Skipping %s: file already exists' % output_filepath)
            print()
            return
        bar = SimpleProgressBar(total_size, len(urls))
    else:
        bar = PiecesProgressBar(total_size, len(urls))

    if len(urls) == 1:
        url = urls[0]
        print('Downloading %s ...' % tr(output_filename))
        bar.update()
        url_save(
            url, output_filepath, bar, refer=refer, faker=faker,
            headers=headers, **kwargs
        )
        bar.done()
    else:
        parts = []
        print('Downloading %s.%s ...' % (tr(title), ext))
        bar.update()
        for i, url in enumerate(urls):
            filename = '%s[%02d].%s' % (title, i, ext)
            filepath = os.path.join(output_dir, filename)
            parts.append(filepath)
            # print 'Downloading %s [%s/%s]...' % (tr(filename), i + 1, len(urls))
            bar.update_piece(i + 1)
            url_save(
                url, filepath, bar, refer=refer, is_part=True, faker=faker,
                headers=headers, **kwargs
            )
        bar.done()

        if not merge:
            print()
            return

        if 'av' in kwargs and kwargs['av']:
            from .processor.ffmpeg import has_ffmpeg_installed
            if has_ffmpeg_installed():
                from .processor.ffmpeg import ffmpeg_concat_av
                ret = ffmpeg_concat_av(parts, output_filepath, ext)
                print('Merged into %s' % output_filename)
                if ret == 0:
                    for part in parts:
                        os.remove(part)

        elif ext in ['flv', 'f4v']:
            try:
                from .processor.ffmpeg import has_ffmpeg_installed
                if has_ffmpeg_installed():
                    from .processor.ffmpeg import ffmpeg_concat_flv_to_mp4
                    ffmpeg_concat_flv_to_mp4(parts, output_filepath)
                else:
                    from .processor.join_flv import concat_flv
                    concat_flv(parts, output_filepath)
                print('Merged into %s' % output_filename)
            except:
                raise
            else:
                for part in parts:
                    os.remove(part)

        elif ext == 'mp4':
            try:
                from .processor.ffmpeg import has_ffmpeg_installed
                if has_ffmpeg_installed():
                    from .processor.ffmpeg import ffmpeg_concat_mp4_to_mp4
                    ffmpeg_concat_mp4_to_mp4(parts, output_filepath)
                else:
                    from .processor.join_mp4 import concat_mp4
                    concat_mp4(parts, output_filepath)
                print('Merged into %s' % output_filename)
            except:
                raise
            else:
                for part in parts:
                    os.remove(part)

        elif ext == 'ts':
            try:
                from .processor.ffmpeg import has_ffmpeg_installed
                if has_ffmpeg_installed():
                    from .processor.ffmpeg import ffmpeg_concat_ts_to_mkv
                    ffmpeg_concat_ts_to_mkv(parts, output_filepath)
                else:
                    from .processor.join_ts import concat_ts
                    concat_ts(parts, output_filepath)
                print('Merged into %s' % output_filename)
            except:
                raise
            else:
                for part in parts:
                    os.remove(part)

        else:
            print("Can't merge %s files" % ext)

    print()


def download_rtmp_url(
    url, title, ext, params={}, total_size=0, output_dir='.', refer=None,
    merge=True, faker=False
):
    assert url
    if dry_run:
        print_user_agent(faker=faker)
        print('Real URL:\n%s\n' % [url])
        if params.get('-y', False):  # None or unset -> False
            print('Real Playpath:\n%s\n' % [params.get('-y')])
        return

    if player:
        from .processor.rtmpdump import play_rtmpdump_stream
        play_rtmpdump_stream(player, url, params)
        return

    from .processor.rtmpdump import (
        has_rtmpdump_installed, download_rtmpdump_stream
    )
    assert has_rtmpdump_installed(), 'RTMPDump not installed.'
    download_rtmpdump_stream(url,  title, ext, params, output_dir)


def download_url_ffmpeg(
    url, title, ext, params={}, total_size=0, output_dir='.', refer=None,
    merge=True, faker=False, stream=True
):
    assert url
    if dry_run:
        print_user_agent(faker=faker)
        print('Real URL:\n%s\n' % [url])
        if params.get('-y', False):  # None or unset ->False
            print('Real Playpath:\n%s\n' % [params.get('-y')])
        return

    if player:
        launch_player(player, [url])
        return

    from .processor.ffmpeg import has_ffmpeg_installed, ffmpeg_download_stream
    assert has_ffmpeg_installed(), 'FFmpeg not installed.'

    global output_filename
    if output_filename:
        dotPos = output_filename.rfind('.')
        if dotPos > 0:
            title = output_filename[:dotPos]
            ext = output_filename[dotPos+1:]
        else:
            title = output_filename

    title = tr(get_filename(title))

    ffmpeg_download_stream(url, title, ext, params, output_dir, stream=stream)


def playlist_not_supported(name):
    def f(*args, **kwargs):
        raise NotImplementedError('Playlist is not supported for ' + name)
    return f


def print_info(site_info, title, type, size, **kwargs):
    if json_output:
        json_output_.print_info(
            site_info=site_info, title=title, type=type, size=size
        )
        return
    if type:
        type = type.lower()
    if type in ['3gp']:
        type = 'video/3gpp'
    elif type in ['asf', 'wmv']:
        type = 'video/x-ms-asf'
    elif type in ['flv', 'f4v']:
        type = 'video/x-flv'
    elif type in ['mkv']:
        type = 'video/x-matroska'
    elif type in ['mp3']:
        type = 'audio/mpeg'
    elif type in ['mp4']:
        type = 'video/mp4'
    elif type in ['mov']:
        type = 'video/quicktime'
    elif type in ['ts']:
        type = 'video/MP2T'
    elif type in ['webm']:
        type = 'video/webm'

    elif type in ['jpg']:
        type = 'image/jpeg'
    elif type in ['png']:
        type = 'image/png'
    elif type in ['gif']:
        type = 'image/gif'

    if type in ['video/3gpp']:
        type_info = '3GPP multimedia file (%s)' % type
    elif type in ['video/x-flv', 'video/f4v']:
        type_info = 'Flash video (%s)' % type
    elif type in ['video/mp4', 'video/x-m4v']:
        type_info = 'MPEG-4 video (%s)' % type
    elif type in ['video/MP2T']:
        type_info = 'MPEG-2 transport stream (%s)' % type
    elif type in ['video/webm']:
        type_info = 'WebM video (%s)' % type
    # elif type in ['video/ogg']:
    #    type_info = 'Ogg video (%s)' % type
    elif type in ['video/quicktime']:
        type_info = 'QuickTime video (%s)' % type
    elif type in ['video/x-matroska']:
        type_info = 'Matroska video (%s)' % type
    # elif type in ['video/x-ms-wmv']:
    #    type_info = 'Windows Media video (%s)' % type
    elif type in ['video/x-ms-asf']:
        type_info = 'Advanced Systems Format (%s)' % type
    # elif type in ['video/mpeg']:
    #    type_info = 'MPEG video (%s)' % type
    elif type in ['audio/mp4', 'audio/m4a']:
        type_info = 'MPEG-4 audio (%s)' % type
    elif type in ['audio/mpeg']:
        type_info = 'MP3 (%s)' % type
    elif type in ['audio/wav', 'audio/wave', 'audio/x-wav']:
        type_info = 'Waveform Audio File Format ({})'.format(type)

    elif type in ['image/jpeg']:
        type_info = 'JPEG Image (%s)' % type
    elif type in ['image/png']:
        type_info = 'Portable Network Graphics (%s)' % type
    elif type in ['image/gif']:
        type_info = 'Graphics Interchange Format (%s)' % type
    elif type in ['m3u8']:
        if 'm3u8_type' in kwargs:
            if kwargs['m3u8_type'] == 'master':
                type_info = 'M3U8 Master {}'.format(type)
        else:
            type_info = 'M3U8 Playlist {}'.format(type)
    else:
        type_info = 'Unknown type (%s)' % type

    maybe_print('Site:      ', site_info)
    maybe_print('Title:     ', unescape_html(tr(title)))
    print('Type:      ', type_info)
    if type != 'm3u8':
        print(
            'Size:      ', round(size / 1048576, 2),
            'MiB (' + str(size) + ' Bytes)'
        )
    if type == 'm3u8' and 'm3u8_url' in kwargs:
        print('M3U8 Url:   {}'.format(kwargs['m3u8_url']))
    print()


def mime_to_container(mime):
    mapping = {
        'video/3gpp': '3gp',
        'video/mp4': 'mp4',
        'video/webm': 'webm',
        'video/x-flv': 'flv',
    }
    if mime in mapping:
        return mapping[mime]
    else:
        return mime.split('/')[1]


def parse_host(host):
    """Parses host name and port number from a string.
    """
    if re.match(r'^(\d+)$', host) is not None:
        return ("0.0.0.0", int(host))
    if re.match(r'^(\w+)://', host) is None:
        host = "//" + host
    o = parse.urlparse(host)
    hostname = o.hostname or "0.0.0.0"
    port = o.port or 0
    return (hostname, port)


def set_proxy(proxy):
    proxy_handler = request.ProxyHandler({
        'http': '%s:%s' % proxy,
        'https': '%s:%s' % proxy,
    })
    opener = request.build_opener(proxy_handler)
    request.install_opener(opener)


def unset_proxy():
    proxy_handler = request.ProxyHandler({})
    opener = request.build_opener(proxy_handler)
    request.install_opener(opener)


# DEPRECATED in favor of set_proxy() and unset_proxy()
def set_http_proxy(proxy):
    if proxy is None:  # Use system default setting
        proxy_support = request.ProxyHandler()
    elif proxy == '':  # Don't use any proxy
        proxy_support = request.ProxyHandler({})
    else:  # Use proxy
        proxy_support = request.ProxyHandler(
            {'http': '%s' % proxy, 'https': '%s' % proxy}
        )
    opener = request.build_opener(proxy_support)
    request.install_opener(opener)


def print_more_compatible(*args, **kwargs):
    import builtins as __builtin__
    """Overload default print function as py (<3.3) does not support 'flush' keyword.
    Although the function name can be same as print to get itself overloaded automatically,
    I'd rather leave it with a different name and only overload it when importing to make less confusion.
    """
    # nothing happens on py3.3 and later
    if sys.version_info[:2] >= (3, 3):
        return __builtin__.print(*args, **kwargs)

    # in lower pyver (e.g. 3.2.x), remove 'flush' keyword and flush it as requested
    doFlush = kwargs.pop('flush', False)
    ret = __builtin__.print(*args, **kwargs)
    if doFlush:
        kwargs.get('file', sys.stdout).flush()
    return ret


def download_main(download, download_playlist, urls, playlist, **kwargs):
    for url in urls:
        if re.match(r'https?://', url) is None:
            url = 'http://' + url

        if playlist:
            download_playlist(url, **kwargs)
        else:
            download(url, **kwargs)


def load_cookies(cookiefile):
    global cookies
    try:
        cookies = cookiejar.MozillaCookieJar(cookiefile)
        cookies.load()
    except Exception:
        import sqlite3
        cookies = cookiejar.MozillaCookieJar()
        con = sqlite3.connect(cookiefile)
        cur = con.cursor()
        try:
            cur.execute("""SELECT host, path, isSecure, expiry, name, value
                        FROM moz_cookies""")
            for item in cur.fetchall():
                c = cookiejar.Cookie(
                    0, item[4], item[5], None, False, item[0],
                    item[0].startswith('.'), item[0].startswith('.'),
                    item[1], False, item[2], item[3], item[3] == '', None,
                    None, {},
                )
                cookies.set_cookie(c)
        except Exception:
            pass
        # TODO: Chromium Cookies
        # SELECT host_key, path, secure, expires_utc, name, encrypted_value
        # FROM cookies
        # http://n8henrie.com/2013/11/use-chromes-cookies-for-easier-downloading-with-python-requests/


def set_socks_proxy(proxy):
    try:
        import socks
        socks_proxy_addrs = proxy.split(':')
        socks.set_default_proxy(
            socks.SOCKS5,
            socks_proxy_addrs[0],
            int(socks_proxy_addrs[1])
        )
        socket.socket = socks.socksocket

        def getaddrinfo(*args):
            return [
                (socket.AF_INET, socket.SOCK_STREAM, 6, '', (args[0], args[1]))
            ]
        socket.getaddrinfo = getaddrinfo
    except ImportError:
        log.w(
            'Error importing PySocks library, socks proxy ignored.'
            'In order to use use socks proxy, please install PySocks.'
        )


def script_main(download, download_playlist, **kwargs):
    logging.basicConfig(format='[%(levelname)s] %(message)s')

    def print_version():
        version = get_version(
            kwargs['repo_path'] if 'repo_path' in kwargs else __version__
        )
        log.i(
            'version {}, a tiny downloader that scrapes the web.'.format(
                version
            )
        )

    parser = argparse.ArgumentParser(
        prog='you-get',
        usage='you-get [OPTION]... URL...',
        description='A tiny downloader that scrapes the web',
        add_help=False,
    )
    parser.add_argument(
        '-V', '--version', action='store_true',
        help='Print version and exit'
    )
    parser.add_argument(
        '-h', '--help', action='store_true',
        help='Print this help message and exit'
    )

    dry_run_grp = parser.add_argument_group(
        'Dry-run options', '(no actual downloading)'
    )
    dry_run_grp = dry_run_grp.add_mutually_exclusive_group()
    dry_run_grp.add_argument(
        '-i', '--info', action='store_true', help='Print extracted information'
    )
    dry_run_grp.add_argument(
        '-u', '--url', action='store_true',
        help='Print extracted information with URLs'
    )
    dry_run_grp.add_argument(
        '--json', action='store_true',
        help='Print extracted URLs in JSON format'
    )

    download_grp = parser.add_argument_group('Download options')
    download_grp.add_argument(
        '-n', '--no-merge', action='store_true', default=False,
        help='Do not merge video parts'
    )
    download_grp.add_argument(
        '--no-caption', action='store_true',
        help='Do not download captions (subtitles, lyrics, danmaku, ...)'
    )
    download_grp.add_argument(
        '-f', '--force', action='store_true', default=False,
        help='Force overwriting existing files'
    )
    download_grp.add_argument(
        '-F', '--format', metavar='STREAM_ID',
        help='Set video format to STREAM_ID'
    )
    download_grp.add_argument(
        '-O', '--output-filename', metavar='FILE', help='Set output filename'
    )
    download_grp.add_argument(
        '-o', '--output-dir', metavar='DIR', default='.',
        help='Set output directory'
    )
    download_grp.add_argument(
        '-p', '--player', metavar='PLAYER',
        help='Stream extracted URL to a PLAYER'
    )
    download_grp.add_argument(
        '-c', '--cookies', metavar='COOKIES_FILE',
        help='Load cookies.txt or cookies.sqlite'
    )
    download_grp.add_argument(
        '-t', '--timeout', metavar='SECONDS', type=int, default=600,
        help='Set socket timeout'
    )
    download_grp.add_argument(
        '-d', '--debug', action='store_true',
        help='Show traceback and other debug info'
    )
    download_grp.add_argument(
        '-I', '--input-file', metavar='FILE', type=argparse.FileType('r'),
        help='Read non-playlist URLs from FILE'
    )
    download_grp.add_argument(
        '-P', '--password', help='Set video visit password to PASSWORD'
    )
    download_grp.add_argument(
        '-l', '--playlist', action='store_true',
        help='Prefer to download a playlist'
    )
    download_grp.add_argument(
        '-a', '--auto-rename', action='store_true', default=False,
        help='Auto rename same name different files'
    )

    proxy_grp = parser.add_argument_group('Proxy options')
    proxy_grp = proxy_grp.add_mutually_exclusive_group()
    proxy_grp.add_argument(
        '-x', '--http-proxy', metavar='HOST:PORT',
        help='Use an HTTP proxy for downloading'
    )
    proxy_grp.add_argument(
        '-y', '--extractor-proxy', metavar='HOST:PORT',
        help='Use an HTTP proxy for extracting only'
    )
    proxy_grp.add_argument(
        '--no-proxy', action='store_true', help='Never use a proxy'
    )
    proxy_grp.add_argument(
        '-s', '--socks-proxy', metavar='HOST:PORT',
        help='Use an SOCKS5 proxy for downloading'
    )

    download_grp.add_argument('--stream', help=argparse.SUPPRESS)
    download_grp.add_argument('--itag', help=argparse.SUPPRESS)

    parser.add_argument('URL', nargs='*', help=argparse.SUPPRESS)

    args = parser.parse_args()

    if args.help:
        print_version()
        parser.print_help()
        sys.exit()
    if args.version:
        print_version()
        sys.exit()

    if args.debug:
        # Set level of root logger to DEBUG
        logging.getLogger().setLevel(logging.DEBUG)

    global force
    global dry_run
    global json_output
    global player
    global extractor_proxy
    global output_filename
    global auto_rename

    output_filename = args.output_filename
    extractor_proxy = args.extractor_proxy

    info_only = args.info
    if args.force:
        force = True
    if args.auto_rename:
        auto_rename = True
    if args.url:
        dry_run = True
    if args.json:
        json_output = True
        # to fix extractors not use VideoExtractor
        dry_run = True
        info_only = False

    if args.cookies:
        load_cookies(args.cookies)

    caption = True
    stream_id = args.format or args.stream or args.itag
    if args.no_caption:
        caption = False
    if args.player:
        player = args.player
        caption = False

    if args.no_proxy:
        set_http_proxy('')
    else:
        set_http_proxy(args.http_proxy)
    if args.socks_proxy:
        set_socks_proxy(args.socks_proxy)

    URLs = []
    if args.input_file:
        logging.debug('you are trying to load urls from %s', args.input_file)
        if args.playlist:
            log.e(
                "reading playlist from a file is unsupported "
                "and won't make your life easier"
            )
            sys.exit(2)
        URLs.extend(args.input_file.read().splitlines())
        args.input_file.close()
    URLs.extend(args.URL)

    if not URLs:
        parser.print_help()
        sys.exit()

    socket.setdefaulttimeout(args.timeout)

    try:
        extra = {}
        if extractor_proxy:
            extra['extractor_proxy'] = extractor_proxy
        if stream_id:
            extra['stream_id'] = stream_id
        download_main(
            download, download_playlist,
            URLs, args.playlist,
            output_dir=args.output_dir, merge=not args.no_merge,
            info_only=info_only, json_output=json_output, caption=caption,
            password=args.password,
            **extra
        )
    except KeyboardInterrupt:
        if args.debug:
            raise
        else:
            sys.exit(1)
    except UnicodeEncodeError:
        if args.debug:
            raise
        log.e(
            '[error] oops, the current environment does not seem to support '
            'Unicode.'
        )
        log.e('please set it to a UTF-8-aware locale first,')
        log.e(
            'so as to save the video (with some Unicode characters) correctly.'
        )
        log.e('you can do it like this:')
        log.e('    (Windows)    % chcp 65001 ')
        log.e('    (Linux)      $ LC_CTYPE=en_US.UTF-8')
        sys.exit(1)
    except Exception:
        if not args.debug:
            log.e('[error] oops, something went wrong.')
            log.e(
                'don\'t panic, c\'est la vie. please try the following steps:'
            )
            log.e('  (1) Rule out any network problem.')
            log.e('  (2) Make sure you-get is up-to-date.')
            log.e('  (3) Check if the issue is already known, on')
            log.e('        https://github.com/soimort/you-get/wiki/Known-Bugs')
            log.e('        https://github.com/soimort/you-get/issues')
            log.e('  (4) Run the command with \'--debug\' option,')
            log.e('      and report this issue with the full output.')
        else:
            print_version()
            log.i(args)
            raise
        sys.exit(1)


def google_search(url):
    keywords = r1(r'https?://(.*)', url)
    url = 'https://www.google.com/search?tbm=vid&q=%s' % parse.quote(keywords)
    page = get_content(url, headers=fake_headers)
    videos = re.findall(
        r'<a href="(https?://[^"]+)" onmousedown="[^"]+"><h3 class="[^"]*">([^<]+)<', page
    )
    vdurs = re.findall(r'<span class="vdur[^"]*">([^<]+)<', page)
    durs = [r1(r'(\d+:\d+)', unescape_html(dur)) for dur in vdurs]
    print('Google Videos search:')
    for v in zip(videos, durs):
        print('- video:  {} [{}]'.format(
            unescape_html(v[0][1]),
            v[1] if v[1] else '?'
        ))
        print('# you-get %s' % log.sprint(v[0][0], log.UNDERLINE))
        print()
    print('Best matched result:')
    return(videos[0][0])


def url_to_module(url):
    try:
        video_host = r1(r'https?://([^/]+)/', url)
        video_url = r1(r'https?://[^/]+(.*)', url)
        assert video_host and video_url
    except AssertionError:
        url = google_search(url)
        video_host = r1(r'https?://([^/]+)/', url)
        video_url = r1(r'https?://[^/]+(.*)', url)

    if video_host.endswith('.com.cn') or video_host.endswith('.ac.cn'):
        video_host = video_host[:-3]
    domain = r1(r'(\.[^.]+\.[^.]+)$', video_host) or video_host
    assert domain, 'unsupported url: ' + url

    # all non-ASCII code points must be quoted (percent-encoded UTF-8)
    url = ''.join([ch if ord(ch) in range(128) else parse.quote(ch) for ch in url])
    video_host = r1(r'https?://([^/]+)/', url)
    video_url = r1(r'https?://[^/]+(.*)', url)

    k = r1(r'([^.]+)', domain)
    if k in SITES:
        return (
            import_module('.'.join(['you_get', 'extractors', SITES[k]])),
            url
        )
    else:
        try:
            location = get_location(url) # t.co isn't happy with fake_headers
        except:
            location = get_location(url, headers=fake_headers)

        if location and location != url and not location.startswith('/'):
            return url_to_module(location)
        else:
            return import_module('you_get.extractors.universal'), url


def any_download(url, **kwargs):
    m, url = url_to_module(url)
    m.download(url, **kwargs)


def any_download_playlist(url, **kwargs):
    m, url = url_to_module(url)
    m.download_playlist(url, **kwargs)


def main(**kwargs):
    script_main(any_download, any_download_playlist, **kwargs)