Source code for coherence.extern.youtubedl.youtubedl

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Author: Ricardo Garcia Gonzalez
# Author: Danny Colligan
# Author: Jean-Michel Sizun (integration within coherence framework)
# License: Public domain code
import html.entities
import http.client
import locale
import math
import netrc
import os
import os.path
import re
import socket
import string
import sys
import time
import urllib
import urllib.error

from coherence.upnp.core.utils import getPage

std_headers = {
    'User-Agent': 'Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.2)'
                  ' Gecko/20090729 Firefox/3.5.2',
    'Accept-Charset': 'ISO-8859-1,utf-8;q=0.7,*;q=0.7',
    'Accept': 'text/xml,application/xml,application/xhtml+xml,'
              'text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5',
    'Accept-Language': 'en-us,en;q=0.5',
}

simple_title_chars = string.ascii_letters + string.digits


def preferredencoding():
    '''Get preferred encoding.

    Returns the best encoding scheme for the system, based on
    locale.getpreferredencoding() and some further tweaks.
    '''
    try:
        pref = locale.getpreferredencoding()
        # Mac OSX systems have this problem sometimes
        if pref == '':
            return 'UTF-8'
        return pref
    except Exception:
        sys.stderr.write(
            'WARNING: problem obtaining preferred encoding. '
            'Falling back to UTF-8.\n')
        return 'UTF-8'


class DownloadError(Exception):
    '''Download Error exception.

    This exception may be thrown by FileDownloader objects if they are not
    configured to continue on errors. They will contain the appropriate
    error message.
    '''
    pass


class SameFileError(Exception):
    '''Same File exception.

    This exception will be thrown by FileDownloader objects if they detect
    multiple files would have to be downloaded to the same file on disk.
    '''
    pass


class PostProcessingError(Exception):
    '''Post Processing exception.

    This exception may be raised by PostProcessor's .run() method to
    indicate an error in the postprocessing task.
    '''
    pass


class UnavailableFormatError(Exception):
    '''Unavailable Format exception.

    This exception will be thrown when a video is requested
    in a format that is not available for that video.
    '''
    pass


class ContentTooShortError(Exception):
    '''Content Too Short exception.

    This exception may be raised by FileDownloader objects when a file they
    download is too small for what the server announced first, indicating
    the connection was probably interrupted.
    '''
    # Both in bytes
    downloaded = None
    expected = None

    def __init__(self, downloaded, expected):
        self.downloaded = downloaded
        self.expected = expected


class FileDownloader(object):
    '''File Downloader class.

    File downloader objects are the ones responsible of downloading the
    actual video file and writing it to disk if the user has requested
    it, among some other tasks. In most cases there should be one per
    program. As, given a video URL, the downloader doesn't know how to
    extract all the needed information, task that InfoExtractors do, it
    has to pass the URL to one of them.

    For this, file downloader objects have a method that allows
    InfoExtractors to be registered in a given order. When it is passed
    a URL, the file downloader handles it to the first InfoExtractor it
    finds that reports being able to handle it. The InfoExtractor extracts
    all the information about the video or videos the URL refers to, and
    asks the FileDownloader to process the video information, possibly
    downloading the video.

    File downloaders accept a lot of parameters. In order not to saturate
    the object constructor with arguments, it receives a dictionary of
    options instead. These options are available through the params
    attribute for the InfoExtractors to use. The FileDownloader also
    registers itself as the downloader in charge for the InfoExtractors
    that are added to it, so this is a "mutual registration".

    Available options:

    username:	Username for authentication purposes.
    password:	Password for authentication purposes.
    usenetrc:	Use netrc for authentication instead.
    quiet:		Do not print messages to stdout.
    forceurl:	Force printing final URL.
    forcetitle:	Force printing title.
    simulate:	Do not download the video files.
    format:		Video format code.
    outtmpl:	Template for output names.
    ignoreerrors:	Do not stop on download errors.
    ratelimit:	Download speed limit, in bytes/sec.
    nooverwrites:    Prevent overwriting files.
    continuedl:    Try to continue downloads if possible.
    '''

    params = None
    _ies = []
    _pps = []
    _download_retcode = None

    def __init__(self, params):
        '''
        Create a FileDownloader object with the given options.
        '''
        self._ies = []
        self._pps = []
        self._download_retcode = 0
        self.params = params

    @staticmethod
    def pmkdir(filename):
        '''
        Create directory components in filename. Similar to Unix "mkdir -p".
        '''
        components = filename.split(os.sep)
        aggregate = [os.sep.join(components[0:x]) for x in
                     range(1, len(components))]
        aggregate = [f'{x}{os.sep}' for x in
                     aggregate]  # Finish names with separator
        for dir in aggregate:
            if not os.path.exists(dir):
                os.mkdir(dir)

    @staticmethod
    def format_bytes(bytes):
        if bytes is None:
            return 'N/A'
        if type(bytes) is str:
            bytes = float(bytes)
        if bytes == 0.0:
            exponent = 0
        else:
            exponent = int(math.log(bytes, 1024.0))
        suffix = 'bkMGTPEZY'[exponent]
        converted = float(bytes) / float(1024 ** exponent)
        return f'{converted:.2f}{suffix}'

    @staticmethod
    def calc_percent(byte_counter, data_len):
        if data_len is None:
            return '---.-%'
        return \
            '%6s' % ('%3.1f%%' %
                     (float(byte_counter) / float(data_len) * 100.0))

    @staticmethod
    def calc_eta(start, now, total, current):
        if total is None:
            return '--:--'
        dif = now - start
        if current == 0 or dif < 0.001:  # One millisecond
            return '--:--'
        rate = float(current) / dif
        eta = int((float(total) - float(current)) / rate)
        (eta_mins, eta_secs) = divmod(eta, 60)
        if eta_mins > 99:
            return '--:--'
        return f'{eta_mins:02d}:{eta_secs:02d}'

    @staticmethod
    def calc_speed(start, now, bytes):
        dif = now - start
        if bytes == 0 or dif < 0.001:  # One millisecond
            return f'{"---b/s":>10}'
        return \
            '%10s' % ('%s/s' % FileDownloader.format_bytes(
                float(bytes) / dif))

    @staticmethod
    def best_block_size(elapsed_time, bytes):
        new_min = max(bytes / 2.0, 1.0)
        new_max = min(max(bytes * 2.0, 1.0), 4194304)  # Do not surpass 4 MB
        if elapsed_time < 0.001:
            return int(new_max)
        rate = bytes / elapsed_time
        if rate > new_max:
            return int(new_max)
        if rate < new_min:
            return int(new_min)
        return int(rate)

    @staticmethod
    def parse_bytes(bytestr):
        '''
        Parse a string indicating a byte quantity into a long integer.
        '''
        matchobj = re.match(r'(?i)^(\d+(?:\.\d+)?)([kMGTPEZY]?)$', bytestr)
        if matchobj is None:
            return None
        number = float(matchobj.group(1))
        multiplier = 1024.0 ** 'bkmgtpezy'.index(matchobj.group(2).lower())
        return int(round(number * multiplier))

    @staticmethod
    def verify_url(url):
        '''
        Verify a URL is valid and data could be downloaded.
        Return real data URL.
        '''
        request = urllib.request.Request(url, None, std_headers)
        data = urllib.request.urlopen(request)
        data.read(1)
        url = data.geturl()
        data.close()
        return url

    def add_info_extractor(self, ie):
        '''Add an InfoExtractor object to the end of the list.'''
        self._ies.append(ie)
        ie.set_downloader(self)

    def add_post_processor(self, pp):
        '''Add a PostProcessor object to the end of the chain.'''
        self._pps.append(pp)
        pp.set_downloader(self)

    def to_stdout(self, message, skip_eol=False):
        '''Print message to stdout if not in quiet mode.'''
        if not self.params.get('quiet', False):
            print(('%s%s' % (message, ['\n', ''][skip_eol])).encode(
                preferredencoding()), end=' ')
            sys.stdout.flush()

    def to_stderr(self, message):
        '''Print message to stderr.'''
        print(message.encode(preferredencoding()), file=sys.stderr)

    def fixed_template(self):
        '''Checks if the output template is fixed.'''
        return re.search(r'(?u)%\(.+?\)s', self.params['outtmpl']) is None

    def trouble(self, message=None):
        '''Determine action to take when a download problem appears.

        Depending on if the downloader has been configured to ignore
        download errors or not, this method may throw an exception or
        not when errors are found, after printing the message.
        '''
        if message is not None:
            self.to_stderr(message)
        if not self.params.get('ignoreerrors', False):
            raise DownloadError(message)
        self._download_retcode = 1
        return self._download_retcode

    def slow_down(self, start_time, byte_counter):
        '''Sleep if the download speed is over the rate limit.'''
        rate_limit = self.params.get('ratelimit', None)
        if rate_limit is None or byte_counter == 0:
            return
        now = time.time()
        elapsed = now - start_time
        if elapsed <= 0.0:
            return
        speed = float(byte_counter) / elapsed
        if speed > rate_limit:
            time.sleep(
                (byte_counter - rate_limit * (now - start_time)) / rate_limit)

    def report_destination(self, filename):
        '''Report destination filename.'''
        self.to_stdout(f'[download] Destination: {filename}')

    def report_progress(self, percent_str, data_len_str, speed_str, eta_str):
        '''Report download progress.'''
        self.to_stdout(
            f'\r[download] {percent_str} of {data_len_str} at '
            f'{speed_str} ETA {eta_str}',
            skip_eol=True)

    def report_resuming_byte(self, resume_len):
        '''Report attemtp to resume at given byte.'''
        self.to_stdout(f'[download] Resuming download at byte {resume_len}')

    def report_file_already_downloaded(self, file_name):
        '''Report file has already been fully downloaded.'''
        self.to_stdout(f'[download] {file_name} has already been downloaded')

    def report_unable_to_resume(self):
        '''Report it was impossible to resume download.'''
        self.to_stdout('[download] Unable to resume')

    def report_finish(self):
        '''Report download finished.'''
        self.to_stdout('')

    def _do_download(self, *args):
        raise NotImplementedError('Error: the _do_download method was removed'
                                  'at some point of the project, operation'
                                  'cancelled')

    def process_info(self, info_dict):
        '''Process a single dictionary returned by an InfoExtractor.'''
        # Do nothing else if in simulate mode
        if self.params.get('simulate', False):
            try:
                info_dict['url'] = self.verify_url(info_dict['url'])
            except (OSError, IOError, urllib.error.URLError,
                    http.client.HTTPException, socket.error) as err:
                raise UnavailableFormatError

            # Forced printings
            if self.params.get('forcetitle', False):
                print(info_dict['title'].encode(preferredencoding()))
            if self.params.get('forceurl', False):
                print(info_dict['url'].encode(preferredencoding()))

            return

        try:
            template_dict = dict(info_dict)
            template_dict['epoch'] = str(int(time.time()))
            filename = self.params['outtmpl'] % template_dict
        except (ValueError, KeyError) as err:
            self.trouble(
                f'ERROR: invalid output template or system charset: {str(err)}'
            )
        if self.params['nooverwrites'] and os.path.exists(filename):
            self.to_stderr(f'WARNING: file exists: {filename}; skipping')
            return

        try:
            self.pmkdir(filename)
        except (OSError, IOError) as err:
            self.trouble(f'ERROR: unable to create directories: {str(err)}')
            return

        try:
            # Fixme: This should be reimplemented, probably that the best shoot
            #  will be to use an external python package to deal with that
            success = self._do_download(filename, info_dict['url'])
        except (urllib.error.URLError,
                http.client.HTTPException,
                socket.error) as err:
            self.trouble(f'ERROR: unable to download video data: {str(err)}')
            return
        except (ContentTooShortError,) as err:
            self.trouble(
                f'ERROR: content too short '
                f'(expected {err.expected} bytes and served {err.downloaded})')
            return
        except (OSError, IOError) as err:
            raise UnavailableFormatError

        if success:
            try:
                self.post_process(filename, info_dict)
            except PostProcessingError as err:
                self.trouble(f'ERROR: postprocessing: {str(err)}')
                return

    def download(self, url_list):
        '''Download a given list of URLs.'''
        if len(url_list) > 1 and self.fixed_template():
            raise SameFileError(self.params['outtmpl'])

        for url in url_list:
            suitable_found = False
            for ie in self._ies:
                # Go to next InfoExtractor if not suitable
                if not ie.suitable(url):
                    continue
                # Suitable InfoExtractor found
                suitable_found = True
                # Extract information from URL and process it
                ie.extract(url)

                # Suitable InfoExtractor had been found; go to next URL
                break

            if not suitable_found:
                self.trouble(f'ERROR: no suitable InfoExtractor: {url}')

        return self._download_retcode

    def get_real_urls(self, url_list):
        '''Download a given list of URLs.'''
        if len(url_list) > 1 and self.fixed_template():
            raise SameFileError(self.params['outtmpl'])

        for url in url_list:
            suitable_found = False
            for ie in self._ies:
                if not ie.suitable(url):
                    continue
                # Suitable InfoExtractor found
                suitable_found = True

                def got_all_results(all_results):
                    results = [x for x in all_results if x is not None]
                    if len(results) != len(all_results):
                        ret_code = self.trouble()

                    if len(results) > 1 and self.fixed_template():
                        raise SameFileError(self.params['outtmpl'])

                    real_urls = []
                    for result in results:
                        real_urls.append(result['url'])
                    return real_urls

                d = ie.extract(url)
                d.addCallback(got_all_results)
                return d

        return []

    def post_process(self, filename, ie_info):
        '''Run the postprocessing chain on the given file.'''
        info = dict(ie_info)
        info['filepath'] = filename
        for pp in self._pps:
            info = pp.run(info)
            if info is None:
                break


# _do_download REMOVED

class InfoExtractor(object):
    '''Information Extractor class.

    Information extractors are the classes that, given a URL, extract
    information from the video (or videos) the URL refers to. This
    information includes the real video URL, the video title and simplified
    title, author and others. The information is stored in a dictionary
    which is then passed to the FileDownloader. The FileDownloader
    processes this information possibly downloading the video to the file
    system, among other possible outcomes. The dictionaries must include
    the following fields:

    id:		Video identifier.
    url:		Final video URL.
    uploader:	Nickname of the video uploader.
    title:		Literal title.
    stitle:		Simplified title.
    ext:		Video filename extension.

    Subclasses of this one should re-define the _real_initialize() and
    _real_extract() methods, as well as the suitable() static method.
    Probably, they should also be instantiated and added to the main
    downloader.
    '''

    _ready = False
    _downloader = None

    def __init__(self, downloader=None):
        '''Constructor. Receives an optional downloader.'''
        self._ready = False
        self.set_downloader(downloader)

    @staticmethod
    def suitable(url):
        '''Receives a URL and returns True if suitable for this IE.'''
        return False

    def initialize(self):
        '''Initializes an instance (authentication, etc).'''
        if not self._ready:
            self._real_initialize()
            self._ready = True

    def extract(self, url):
        '''Extracts URL information and returns it in list of dicts.'''
        self.initialize()
        return self._real_extract(url)

    def set_downloader(self, downloader):
        '''Sets the downloader for this IE.'''
        self._downloader = downloader

    def to_stdout(self, message):
        '''Print message to stdout if downloader is not in quiet mode.'''
        if self._downloader is None or not self._downloader.get_params().get(
                'quiet', False):
            print(message)

    def to_stderr(self, message):
        '''Print message to stderr.'''
        print(message, file=sys.stderr)

    def _real_initialize(self):
        '''Real initialization process. Redefine in subclasses.'''
        pass

    def _real_extract(self, url):
        '''Real extraction process. Redefine in subclasses.'''
        pass


class YoutubeIE(InfoExtractor):
    '''Information extractor for youtube.com.'''

    _VALID_URL = r'^((?:https://)?(?:\w+\.)?youtube\.com/(?:(?:v/)|' \
                 r'(?:(?:watch(?:\.php)?)?\?(?:.+&)?v=)))?([0-9A-Za-z_-]+)' \
                 r'(?(1).+)?$'
    _LANG_URL = r'https://uk.youtube.com/?hl=en&persist_hl=1' \
                r'&gl=US&persist_gl=1&opt_out_ackd=1'
    _LOGIN_URL = 'https://www.youtube.com/signup?next=/&gl=US&hl=en'
    _AGE_URL = 'https://www.youtube.com/verify_age?next_url=/&gl=US&hl=en'
    _NETRC_MACHINE = 'youtube'
    # _available_formats listed in order of priority for -b flag
    _available_formats = ['22', '35', '18', '5', '17', '13', None]
    _video_extensions = {
        '13': '3gp',
        '17': 'mp4',
        '18': 'mp4',
        '22': 'mp4',
    }

    @staticmethod
    def suitable(url):
        return re.match(YoutubeIE._VALID_URL, url) is not None

    @staticmethod
    def htmlentity_transform(matchobj):
        '''Transforms an HTML entity to a Unicode character.'''
        entity = matchobj.group(1)

        # Known non-numeric HTML entity
        if entity in html.entities.name2codepoint:
            return chr(html.entities.name2codepoint[entity])

        # Unicode character
        mobj = re.match(r'(?u)#(x?\d+)', entity)
        if mobj is not None:
            numstr = mobj.group(1)
            if numstr.startswith('x'):
                base = 16
                numstr = f'0{numstr}'
            else:
                base = 10
            return chr(int(numstr, base))

        # Unknown entity in name, return its literal representation
        return f'&{entity};'

    def report_lang(self):
        '''Report attempt to set language.'''
        self._downloader.to_stdout('[youtube] Setting language')

    def report_login(self):
        '''Report attempt to log in.'''
        self._downloader.to_stdout('[youtube] Logging in')

    def report_age_confirmation(self):
        '''Report attempt to confirm age.'''
        self._downloader.to_stdout('[youtube] Confirming age')

    def report_video_info_webpage_download(self, video_id):
        '''Report attempt to download video info webpage.'''
        self._downloader.to_stdout(
            f'[youtube] {video_id}: Downloading video info webpage')

    def report_information_extraction(self, video_id):
        '''Report attempt to extract video information.'''
        self._downloader.to_stdout(
            f'[youtube] {video_id}: Extracting video information')

    def report_unavailable_format(self, video_id, format):
        '''Report extracted video URL.'''
        self._downloader.to_stdout(
            f'[youtube] {video_id}: Format {format} not available')

    def report_video_url(self, video_id, video_real_url):
        '''Report extracted video URL.'''
        self._downloader.to_stdout(
            f'[youtube] {video_id}: URL: {video_real_url}')

    def _real_initialize(self):

        if self._downloader is None:
            return

        username = None
        password = None
        downloader_params = self._downloader.params

        # Attempt to use provided username and password or .netrc data
        if downloader_params.get('username', None) is not None:
            username = downloader_params['username']
            password = downloader_params['password']
        elif downloader_params.get('usenetrc', False):
            try:
                info = netrc.netrc().authenticators(self._NETRC_MACHINE)
                if info is not None:
                    username = info[0]
                    password = info[2]
                else:
                    raise netrc.NetrcParseError(
                        f'No authenticators for {self._NETRC_MACHINE}')
            except (IOError, netrc.NetrcParseError) as err:
                self._downloader.to_stderr(
                    f'WARNING: parsing .netrc: {str(err)}')
                return

        def gotAgeConfirmedPage(result):
            print('Age confirmed in Youtube')

        def gotLoggedInPage(result):
            data, headers = result
            if re.search(r'(?i)<form[^>]* name="loginForm"', data) is not None:
                print('WARNING: unable to log in: bad username or password')
                return
            print('logged in in Youtube')

            # Confirm age
            age_form = {
                'next_url': '/',
                'action_confirm': 'Confirm',
            }
            postdata = urllib.parse.urlencode(age_form)
            d = getPage(self._AGE_URL, postdata=postdata, headers=std_headers)
            d.addCallback(gotAgeConfirmedPage)

        def gotLoginError(error):
            print(f'Unable to login to Youtube: '
                  f'{username}:{password} @ {self._LOGIN_URL}')
            print(f'Error: {error}')
            return

        def gotLanguageSet(result):
            data, headers = result
            # No authentication to be performed
            if username is None:
                return
            # Log in
            login_form = {
                'current_form': 'loginForm',
                'next': '/',
                'action_login': 'Log In',
                'username': username,
                'password': password,
            }
            postdata = urllib.parse.urlencode(login_form)
            d = getPage(self._LOGIN_URL, method='POST', postdata=postdata,
                        headers=std_headers)
            d.addCallbacks(gotLoggedInPage, gotLoginError)

        def gotLanguageSetError(error):
            print(f'Unable to process Youtube request: {self._LANG_URL}')
            print(f'Error: {error}')
            return

        # Set language (will lead to log in, and then age confirmation)
        d = getPage(self._LANG_URL, headers=std_headers)
        d.addCallbacks(gotLanguageSet, gotLanguageSetError)

    def _real_extract(self, url):
        # Extract video id from URL
        mobj = re.match(self._VALID_URL, url)
        if mobj is None:
            self._downloader.trouble(f'ERROR: invalid URL: {url}')
            return
        video_id = mobj.group(2)

        # Downloader parameters
        best_quality = False
        format_param = None
        video_extension = None

        quality_index = 0
        if self._downloader is not None:
            params = self._downloader.params
            format_param = params.get('format', None)
            if format_param == '0':
                format_param = self._available_formats[quality_index]
                best_quality = True
        video_extension = self._video_extensions.get(format_param, 'flv')

        # video info
        video_info_url = \
            f'https://www.youtube.com/get_video_info?&video_id={video_id}&' \
            f'el=detailpage&ps=default&eurl=&gl=US&hl=en'
        if format_param is not None:
            video_info_url = f'{video_info_url}&fmt={format_param}'

        def gotPage(result, format_param, video_extension):
            video_info_webpage, headers = result

            # check format
            if format_param == '22':
                print('Check if HD video exists...')
                mobj = re.search(r'var isHDAvailable = true;',
                                 video_info_webpage)
                if mobj is None:
                    print('No HD video -> switch back to SD')
                    format_param = '18'
                else:
                    print('...HD video OK!')

            # "t" param
            mobj = re.search(r'(?m)&token=([^&]+)(?:&|$)', video_info_webpage)
            if mobj is None:
                # Attempt to see if YouTube has issued an error message
                mobj = re.search(r'(?m)&reason=([^&]+)(?:&|$)',
                                 video_info_webpage)
                if mobj is None:
                    self.to_stderr('ERROR: unable to extract "t" parameter')
                    print(video_info_webpage)
                    return [None]
                else:
                    reason = urllib.parse.unquote_plus(mobj.group(1))
                    self.to_stderr(
                        f'ERROR: YouTube said: {reason.decode("utf-8")}')

            token = urllib.parse.unquote(mobj.group(1))
            video_real_url = \
                f'https://www.youtube.com/get_video?video_id={video_id}&' \
                f't={token}&eurl=&el=detailpage&ps=default&gl=US&hl=en'
            if format_param is not None:
                video_real_url = f'{video_real_url}&fmt={format_param}'

            # uploader
            mobj = re.search(r'(?m)&author=([^&]+)(?:&|$)', video_info_webpage)
            if mobj is None:
                self._downloader.trouble(
                    'ERROR: unable to extract uploader nickname')
                return
            video_uploader = urllib.parse.unquote(mobj.group(1))

            # title
            mobj = re.search(r'(?m)&title=([^&]+)(?:&|$)', video_info_webpage)
            if mobj is None:
                self._downloader.trouble(
                    'ERROR: unable to extract video title')
                return
            video_title = urllib.parse.unquote(mobj.group(1))
            video_title = video_title.decode('utf-8')
            video_title = re.sub(r'(?u)&(.+?);', self.htmlentity_transform,
                                 video_title)
            video_title = video_title.replace(os.sep, '%')

            # simplified title
            simple_title = re.sub(fr'(?u)([^{simple_title_chars}]+)', r'_',
                                  video_title)
            simple_title = simple_title.strip(r'_')

            # Return information
            return [{
                'id': video_id.decode('utf-8'),
                'url': video_real_url.decode('utf-8'),
                'uploader': video_uploader.decode('utf-8'),
                'title': video_title,
                'stitle': simple_title,
                'ext': video_extension.decode('utf-8'),
            }]

        def gotError(error):
            print(f'Unable to process Youtube request: {url}')
            print(f'Error: {error}')
            return [None]

        d = getPage(video_info_url, headers=std_headers)
        d.addCallback(gotPage, format_param, video_extension)
        d.addErrback(gotError)
        return d


class MetacafeIE(InfoExtractor):
    '''Information Extractor for metacafe.com.'''

    _VALID_URL = r'(?:https://)?(?:www\.)?metacafe\.com/' \
                 r'watch/([^/]+)/([^/]+)/.*'
    _DISCLAIMER = 'https://www.metacafe.com/family_filter/'
    _FILTER_POST = 'https://www.metacafe.com/f/index.php?' \
                   'inputType=filter&controllerGroup=user'
    _youtube_ie = None

    def __init__(self, youtube_ie, downloader=None):
        InfoExtractor.__init__(self, downloader)
        self._youtube_ie = youtube_ie

    @staticmethod
    def suitable(url):
        return re.match(MetacafeIE._VALID_URL, url) is not None

    def report_disclaimer(self):
        '''Report disclaimer retrieval.'''
        self._downloader.to_stdout('[metacafe] Retrieving disclaimer')

    def report_age_confirmation(self):
        '''Report attempt to confirm age.'''
        self._downloader.to_stdout('[metacafe] Confirming age')

    def report_download_webpage(self, video_id):
        '''Report webpage download.'''
        self._downloader.to_stdout(
            f'[metacafe] {video_id}: Downloading webpage')

    def report_extraction(self, video_id):
        '''Report information extraction.'''
        self._downloader.to_stdout(
            f'[metacafe] {video_id}: Extracting information')

    def _real_initialize(self):
        # Retrieve disclaimer
        request = urllib.request.Request(self._DISCLAIMER, None, std_headers)
        try:
            self.report_disclaimer()
            disclaimer = urllib.request.urlopen(request).read()
        except (urllib.error.URLError,
                http.client.HTTPException,
                socket.error) as err:
            self._downloader.trouble(
                f'ERROR: unable to retrieve disclaimer: {str(err)}')
            return

        # Confirm age
        disclaimer_form = {
            'filters': '0',
            'submit': 'Continue - I\'m over 18',
        }
        request = urllib.request.Request(
            self._FILTER_POST, urllib.parse.urlencode(
                disclaimer_form), std_headers)
        try:
            self.report_age_confirmation()
            disclaimer = urllib.request.urlopen(request).read()
        except (urllib.error.URLError,
                http.client.HTTPException,
                socket.error) as err:
            self._downloader.trouble(
                f'ERROR: unable to confirm age: {str(err)}')
            return

    def _real_extract(self, url):
        # Extract id and simplified title from URL
        mobj = re.match(self._VALID_URL, url)
        if mobj is None:
            self._downloader.trouble(f'ERROR: invalid URL: {url}')
            return

        video_id = mobj.group(1)

        # Check if video comes from YouTube
        mobj2 = re.match(r'^yt-(.*)$', video_id)
        if mobj2 is not None:
            self._youtube_ie.extract(
                f'https://www.youtube.com/watch?v={mobj2.group(1)}')
            return

        simple_title = mobj.group(2).decode('utf-8')
        video_extension = 'flv'

        # Retrieve video webpage to extract further information
        request = urllib.request.Request(
            f'https://www.metacafe.com/watch/{video_id}/')
        try:
            self.report_download_webpage(video_id)
            webpage = urllib.request.urlopen(request).read()
        except (urllib.error.URLError,
                http.client.HTTPException,
                socket.error) as err:
            self._downloader.trouble(
                f'ERROR: unable retrieve video webpage: {str(err)}')
            return

        # Extract URL, uploader and title from webpage
        self.report_extraction(video_id)
        mobj = re.search(r'(?m)&mediaURL=([^&]+)', webpage)
        if mobj is None:
            self._downloader.trouble('ERROR: unable to extract media URL')
            return
        mediaURL = urllib.parse.unquote(mobj.group(1))
        # mobj = re.search(r'(?m)&gdaKey=(.*?)&', webpage)
        # if mobj is None:
        #    self._downloader.trouble(u'ERROR: unable to extract gdaKey')
        #    return
        # gdaKey = mobj.group(1)
        #
        # video_url = f'{mediaURL}?__gda__={gdaKey}'

        video_url = mediaURL

        mobj = re.search(r'(?im)<title>(.*) - Video</title>', webpage)
        if mobj is None:
            self._downloader.trouble('ERROR: unable to extract title')
            return
        video_title = mobj.group(1).decode('utf-8')

        mobj = re.search(
            r'(?ms)<li id="ChnlUsr">.*?Submitter:.*?<a .*?>(.*?)<', webpage)
        if mobj is None:
            self._downloader.trouble(
                'ERROR: unable to extract uploader nickname')
            return
        video_uploader = mobj.group(1)

        try:
            # Process video information
            self._downloader.process_info({
                'id': video_id.decode('utf-8'),
                'url': video_url.decode('utf-8'),
                'uploader': video_uploader.decode('utf-8'),
                'title': video_title,
                'stitle': simple_title,
                'ext': video_extension.decode('utf-8'),
            })
        except UnavailableFormatError:
            self._downloader.trouble('ERROR: format not available for video')


class YoutubeSearchIE(InfoExtractor):
    '''Information Extractor for YouTube search queries.'''
    _VALID_QUERY = r'ytsearch(\d+|all)?:[\s\S]+'
    _TEMPLATE_URL = 'https://www.youtube.com/results?' \
                    'search_query=%s&page=%s&gl=US&hl=en'
    _VIDEO_INDICATOR = r'href="/watch\?v=.+?"'
    _MORE_PAGES_INDICATOR = r'(?m)>\s*Next\s*</a>'
    _youtube_ie = None
    _max_youtube_results = 1000

    def __init__(self, youtube_ie, downloader=None):
        InfoExtractor.__init__(self, downloader)
        self._youtube_ie = youtube_ie

    @staticmethod
    def suitable(url):
        return re.match(YoutubeSearchIE._VALID_QUERY, url) is not None

    def report_download_page(self, query, pagenum):
        '''Report attempt to download playlist page with given number.'''
        self._downloader.to_stdout(
            f'[youtube] query "{query}": Downloading page {pagenum}')

    def _real_initialize(self):
        self._youtube_ie.initialize()

    def _real_extract(self, query):
        mobj = re.match(self._VALID_QUERY, query)
        if mobj is None:
            self._downloader.trouble(
                f'ERROR: invalid search query "{query}"')
            return

        prefix, query = query.split(':')
        prefix = prefix[8:]
        if prefix == '':
            self._download_n_results(query, 1)
            return
        elif prefix == 'all':
            self._download_n_results(query, self._max_youtube_results)
            return
        else:
            try:
                n = int(prefix)
                if n <= 0:
                    self._downloader.trouble(
                        f'ERROR: invalid download number {n} '
                        f'for query "{query}"')
                    return
                elif n > self._max_youtube_results:
                    self._downloader.to_stderr(
                        f'WARNING: ytsearch returns max '
                        f'{self._max_youtube_results:d} '
                        f'results (you requested {n:d})')
                    n = self._max_youtube_results
                self._download_n_results(query, n)
                return
            except ValueError:  # parsing prefix as integer fails
                self._download_n_results(query, 1)
                return

    def _download_n_results(self, query, n):
        '''Downloads a specified number of results for a query'''

        video_ids = []
        already_seen = set()
        pagenum = 1

        while True:
            self.report_download_page(query, pagenum)
            result_url = self._TEMPLATE_URL % (
                urllib.parse.quote_plus(query), pagenum)
            request = urllib.request.Request(result_url, None, std_headers)
            try:
                page = urllib.request.urlopen(request).read()
            except (urllib.error.URLError, http.client.HTTPException,
                    socket.error) as err:
                self._downloader.trouble(
                    f'ERROR: unable to download webpage: {str(err)}')
                return

            # Extract video identifiers
            for mobj in re.finditer(self._VIDEO_INDICATOR, page):
                video_id = \
                    page[mobj.span()[0]:mobj.span()[1]].split('=')[2][:-1]
                if video_id not in already_seen:
                    video_ids.append(video_id)
                    already_seen.add(video_id)
                    if len(video_ids) == n:
                        # Specified n videos reached
                        for id in video_ids:
                            self._youtube_ie.extract(
                                f'https://www.youtube.com/watch?v={id}')
                        return

            if re.search(self._MORE_PAGES_INDICATOR, page) is None:
                for id in video_ids:
                    self._youtube_ie.extract(
                        f'https://www.youtube.com/watch?v={id}')
                return

            pagenum = pagenum + 1


class YoutubePlaylistIE(InfoExtractor):
    '''Information Extractor for YouTube playlists.'''

    _VALID_URL = r'(?:https://)?(?:\w+\.)?youtube.com/' \
                 r'(?:view_play_list|my_playlists)\?.*?p=([^&]+).*'
    _TEMPLATE_URL = 'https://www.youtube.com/view_play_list?' \
                    'p=%s&page=%s&gl=US&hl=en'
    _VIDEO_INDICATOR = r'/watch\?v=(.+?)&'
    _MORE_PAGES_INDICATOR = r'/view_play_list?p=%s&page=%s'
    _youtube_ie = None

    def __init__(self, youtube_ie, downloader=None):
        InfoExtractor.__init__(self, downloader)
        self._youtube_ie = youtube_ie

    @staticmethod
    def suitable(url):
        return re.match(YoutubePlaylistIE._VALID_URL, url) is not None

    def report_download_page(self, playlist_id, pagenum):
        '''Report attempt to download playlist page with given number.'''
        self.to_stdout(
            f'[youtube] PL {playlist_id}: Downloading page #{pagenum}')

    def _real_initialize(self):
        self._youtube_ie.initialize()

    def _real_extract(self, url):
        # Extract playlist id
        mobj = re.match(self._VALID_URL, url)
        if mobj is None:
            self._downloader.trouble(f'ERROR: invalid url: {url}')
            return

        # Download playlist pages
        playlist_id = mobj.group(1)
        video_ids = []
        pagenum = 1

        while True:
            self.report_download_page(playlist_id, pagenum)
            request = urllib.request.Request(
                self._TEMPLATE_URL % (playlist_id, pagenum), None, std_headers)
            try:
                page = urllib.request.urlopen(request).read()
            except (urllib.error.URLError, http.client.HTTPException,
                    socket.error) as err:
                self._downloader.trouble(
                    f'ERROR: unable to download webpage: {str(err)}')
                return

            # Extract video identifiers
            ids_in_page = []
            for mobj in re.finditer(self._VIDEO_INDICATOR, page):
                if mobj.group(1) not in ids_in_page:
                    ids_in_page.append(mobj.group(1))
            video_ids.extend(ids_in_page)

            if (self._MORE_PAGES_INDICATOR % (
                    playlist_id.upper(), pagenum + 1)) not in page:
                break
            pagenum = pagenum + 1

        for id in video_ids:
            self._youtube_ie.extract(f'https://www.youtube.com/watch?v={id}')
        return


class PostProcessor(object):
    '''Post Processor class.

    PostProcessor objects can be added to downloaders with their
    add_post_processor() method. When the downloader has finished a
    successful download, it will take its internal chain of PostProcessors
    and start calling the run() method on each one of them, first with
    an initial argument and then with the returned value of the previous
    PostProcessor.

    The chain will be stopped if one of them ever returns None or the end
    of the chain is reached.

    PostProcessor objects follow a "mutual registration" process similar
    to InfoExtractor objects.
    '''

    _downloader = None

    def __init__(self, downloader=None):
        self._downloader = downloader

    def to_stdout(self, message):
        '''Print message to stdout if downloader is not in quiet mode.'''
        if self._downloader is None or not self._downloader.get_params().get(
                'quiet', False):
            print(message)

    def to_stderr(self, message):
        '''Print message to stderr.'''
        print(message, file=sys.stderr)

    def set_downloader(self, downloader):
        '''Sets the downloader for this PP.'''
        self._downloader = downloader

    def run(self, information):
        '''Run the PostProcessor.

        The "information" argument is a dictionary like the ones
        composed by InfoExtractors. The only difference is that this
        one has an extra field called "filepath" that points to the
        downloaded file.

        When this method returns None, the postprocessing chain is
        stopped. However, this method may return an information
        dictionary that will be passed to the next postprocessing
        object in the chain. It can be the one it received after
        changing some fields.

        In addition, this method may raise a PostProcessingError
        exception that will be taken into account by the downloader
        it was called from.
        '''
        return information  # by default, do nothing


# MAIN PROGRAM
if __name__ == '__main__':
    try:
        # Modules needed only when running the main program
        import getpass
        import optparse

        # General configuration
        urllib.request.install_opener(
            urllib.request.build_opener(urllib.request.ProxyHandler()))
        urllib.request.install_opener(
            urllib.request.build_opener(urllib.request.HTTPCookieProcessor()))
        socket.setdefaulttimeout(
            300)  # 5 minutes should be enough (famous last words)

        # Parse command line
        parser = optparse.OptionParser(
            usage='Usage: %prog [options] url...',
            version='2009.09.13',
            conflict_handler='resolve',
        )
        parser.add_option(
            '-h', '--help',
            action='help', help='print this help text and exit')
        parser.add_option(
            '-v', '--version',
            action='version',
            help='print program version and exit')
        parser.add_option(
            '-i', '--ignore-errors',
            action='store_true', dest='ignoreerrors',
            help='continue on download errors', default=False)
        parser.add_option(
            '-r', '--rate-limit',
            dest='ratelimit', metavar='L',
            help='download rate limit (e.g. 50k or 44.6m)')

        authentication = optparse.OptionGroup(parser, 'Authentication Options')
        authentication.add_option(
            '-u', '--username',
            dest='username', metavar='UN',
            help='account username')
        authentication.add_option(
            '-p', '--password',
            dest='password', metavar='PW',
            help='account password')
        authentication.add_option(
            '-n', '--netrc',
            action='store_true', dest='usenetrc',
            help='use .netrc authentication data',
            default=False)
        parser.add_option_group(authentication)

        video_format = optparse.OptionGroup(parser, 'Video Format Options')
        video_format.add_option(
            '-f', '--format',
            action='store', dest='format', metavar='FMT',
            help='video format code')
        video_format.add_option(
            '-b', '--best-quality',
            action='store_const', dest='format',
            help='download the best quality video possible',
            const='0')
        video_format.add_option(
            '-m', '--mobile-version',
            action='store_const', dest='format',
            help='alias for -f 17', const='17')
        video_format.add_option(
            '-d', '--high-def',
            action='store_const', dest='format',
            help='alias for -f 22', const='22')
        parser.add_option_group(video_format)

        verbosity = optparse.OptionGroup(
            parser, 'Verbosity / Simulation Options')
        verbosity.add_option(
            '-q', '--quiet',
            action='store_true', dest='quiet',
            help='activates quiet mode', default=False)
        verbosity.add_option(
            '-s', '--simulate',
            action='store_true', dest='simulate',
            help='do not download video', default=False)
        verbosity.add_option(
            '-g', '--get-url',
            action='store_true', dest='geturl',
            help='simulate, quiet but print URL',
            default=False)
        verbosity.add_option(
            '-e', '--get-title',
            action='store_true', dest='gettitle',
            help='simulate, quiet but print title',
            default=False)
        parser.add_option_group(verbosity)

        filesystem = optparse.OptionGroup(parser, 'Filesystem Options')
        filesystem.add_option(
            '-t', '--title',
            action='store_true', dest='usetitle',
            help='use title in file name', default=False)
        filesystem.add_option(
            '-l', '--literal',
            action='store_true', dest='useliteral',
            help='use literal title in file name',
            default=False)
        filesystem.add_option(
            '-o', '--output',
            dest='outtmpl', metavar='TPL',
            help='output filename template')
        filesystem.add_option(
            '-a', '--batch-file',
            dest='batchfile', metavar='F',
            help='file containing URLs to download')
        filesystem.add_option(
            '-w', '--no-overwrites',
            action='store_true', dest='nooverwrites',
            help='do not overwrite files', default=False)
        filesystem.add_option(
            '-c', '--continue',
            action='store_true', dest='continue_dl',
            help='resume partially downloaded files',
            default=False)
        parser.add_option_group(filesystem)

        (opts, args) = parser.parse_args()

        # Batch file verification
        batchurls = []
        if opts.batchfile is not None:
            try:
                batchurls = open(opts.batchfile, 'r').readlines()
                batchurls = [x.strip() for x in batchurls]
                batchurls = [x for x in batchurls if len(x) > 0]
            except IOError:
                sys.exit('ERROR: batch file could not be read')
        all_urls = batchurls + args

        # Conflicting, missing and erroneous options
        if len(all_urls) < 1:
            parser.error('you must provide at least one URL')
        if opts.usenetrc and (
                opts.username is not None or opts.password is not None):
            parser.error(
                'using .netrc conflicts with giving username/password')
        if opts.password is not None and opts.username is None:
            parser.error('account username missing')
        if opts.outtmpl is not None and (opts.useliteral or opts.usetitle):
            parser.error(
                'using output template conflicts '
                'with using title or literal title')
        if opts.usetitle and opts.useliteral:
            parser.error('using title conflicts with using literal title')
        if opts.username is not None and opts.password is None:
            opts.password = getpass.getpass(
                'Type account password and press return:')
        if opts.ratelimit is not None:
            numeric_limit = FileDownloader.parse_bytes(opts.ratelimit)
            if numeric_limit is None:
                parser.error('invalid rate limit specified')
            opts.ratelimit = numeric_limit

        # Information extractors
        youtube_ie = YoutubeIE()
        metacafe_ie = MetacafeIE(youtube_ie)
        youtube_pl_ie = YoutubePlaylistIE(youtube_ie)
        youtube_search_ie = YoutubeSearchIE(youtube_ie)

        # File downloader
        fd = FileDownloader({
            'usenetrc': opts.usenetrc,
            'username': opts.username,
            'password': opts.password,
            'quiet': (opts.quiet or opts.geturl or opts.gettitle),
            'forceurl': opts.geturl,
            'forcetitle': opts.gettitle,
            'simulate': (opts.simulate or opts.geturl or opts.gettitle),
            'format': opts.format,
            'outtmpl':
                ((opts.outtmpl is not None and opts.outtmpl.decode(
                    preferredencoding())) or
                 (opts.usetitle and '%(stitle)s-%(id)s.%(ext)s') or
                 (opts.useliteral and '%(title)s-%(id)s.%(ext)s') or
                 '%(id)s.%(ext)s'),
            'ignoreerrors': opts.ignoreerrors,
            'ratelimit': opts.ratelimit,
            'nooverwrites': opts.nooverwrites,
            'continuedl': opts.continue_dl,
        })
        fd.add_info_extractor(youtube_search_ie)
        fd.add_info_extractor(youtube_pl_ie)
        fd.add_info_extractor(metacafe_ie)
        fd.add_info_extractor(youtube_ie)
        retcode = fd.download(all_urls)
        sys.exit(retcode)

    except DownloadError:
        sys.exit(1)
    except SameFileError:
        sys.exit('ERROR: fixed output name but more than one file to download')
    except KeyboardInterrupt:
        sys.exit('\nERROR: Interrupted by user')