import getpass

import httplib

import math

import netrc

import optparse

import os

import re

import socket

import string

import sys

import time

import urllib2

 

const_1k = 1024

const_initial_block_size = 10 * const_1k

const_epsilon = 0.0001

const_timeout = 120

 

const_video_url_str = 'http://www.youtube.com/watch?v=%s'

const_video_url_re = re.compile(r'^((?:http://)?(?:\w+\.)?youtube\.com/(?:v/|(?:watch(?:\.php)?)?\?(?:.+&)?v=))?([0-9A-Za-z_-]+)(?(1)[&/].*)?$')

const_login_url_str = 'http://www.youtube.com/login?next=/watch%%3Fv%%3D%s'

const_login_post_str = 'current_form=loginForm&next=%%2Fwatch%%3Fv%%3D%s&username=%s&password=%s&action_login=Log+In'

const_age_url_str = 'http://www.youtube.com/verify_age?next_url=/watch%%3Fv%%3D%s'

const_age_post_str = 'next_url=%%2Fwatch%%3Fv%%3D%s&action_confirm=Confirm'

const_url_t_param_re = re.compile(r', "t": "([^"]+)"')

const_video_url_real_str = 'http://www.youtube.com/get_video?video_id=%s&t=%s'

const_video_title_re = re.compile(r'<title>YouTube - ([^<]*)</title>', re.M | re.I)

 

def error_advice_exit(error_text):

        sys.stderr.write('Error: %s.\n' % error_text)

        sys.stderr.write('Try again several times. It may be a temporary problem.\n')

        sys.stderr.write('Other typical problems:\n\n')

        sys.stderr.write('* Video no longer exists.\n')

        sys.stderr.write('* Video requires age confirmation but you did not provide an account.\n')

        sys.stderr.write('* You provided the account data, but it is not valid.\n')

        sys.stderr.write('* The connection was cut suddenly for some reason.\n')

        sys.stderr.write('* YouTube changed their system, and the program no longer works.\n')

        sys.stderr.write('\nTry to confirm you are able to view the video using a web browser.\n')

        sys.stderr.write('Use the same video URL and account information, if needed, with this program.\n')

        sys.stderr.write('When using a proxy, make sure http_proxy has http://host:port format.\n')

        sys.stderr.write('Try again several times and contact me if the problem persists.\n')

        sys.exit('\n')

 

def request_create(url, data=None):

        retval = urllib2.Request(url)

        if data is not None:

                retval.add_data(data)

        # Try to mimic Firefox, at least a little bit

        retval.add_header('User-Agent', 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.11) Gecko/20071127 Firefox/2.0.0.11')

        retval.add_header('Accept-Charset', 'ISO-8859-1,utf-8;q=0.7,*;q=0.7')

        retval.add_header('Accept', 'text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5')

        retval.add_header('Accept-Language', 'en-us,en;q=0.5')

        return retval

 

def perform_request(url, data=None):

        request = request_create(url, data)

        response = urllib2.urlopen(request)

        return response

 

def cond_print(str):

        global cmdl_opts

        if not (cmdl_opts.quiet or cmdl_opts.get_url):

                sys.stdout.write(str)

                sys.stdout.flush()

 

def title_string_norm(title):

        title = ''.join((x in string.ascii_letters or x in string.digits) and x or ' ' for x in title)

        title = '_'.join(title.split())

        title = title.lower()

        return title

 

def download_step(return_data_flag, step_title, step_error, url, post_data=None):

        try:

                cond_print('%s... ' % step_title)

                data = perform_request(url, post_data).read()

                cond_print('done.\n')

                if return_data_flag:

                        return data

                return None

 

        except (urllib2.URLError, ValueError, httplib.HTTPException, TypeError, socket.error):

                cond_print('failed.\n')

                error_advice_exit(step_error)

 

        except KeyboardInterrupt:

                sys.exit('\n')

 

def extract_step(step_title, step_error, regexp, data):

        try:

                cond_print('%s... ' % step_title)

                match = regexp.search(data)

               

                if match is None:

                        cond_print('failed.\n')

                        error_advice_exit(step_error)

               

                extracted_data = match.group(1)

                cond_print('done.\n')

                return extracted_data

       

        except KeyboardInterrupt:

                sys.exit('\n')

 

def new_block_size(before, after, bytes):

        new_min = max(bytes / 2.0, 1.0)

        new_max = max(bytes * 2.0, 1.0)

        dif = after - before

        if dif < const_epsilon:

                return int(new_max)

        rate = bytes / dif

        if rate > new_max:

                return int(new_max)

        if rate < new_min:

                return int(new_min)

        return int(rate)

 

def optimum_k_exp(num_bytes):

        global const_1k

        if num_bytes == 0:

                return 0

        return long(math.log(num_bytes, const_1k))

 

def format_bytes(num_bytes):

        global const_1k

        try:

                exp = optimum_k_exp(num_bytes)

                suffix = 'bkMGTPEZY'[exp]

                if exp == 0:

                        return '%s%s' % (num_bytes, suffix)

                converted = float(num_bytes) / float(const_1k**exp)

                return '%.2f%s' % (converted, suffix)

        except IndexError:

                sys.exit('Error: internal error formatting number of bytes.')

 

def calc_eta(start, now, total, current):

        dif = now - start

        if current == 0 or dif < const_epsilon:

                return '--:--'

        rate = float(current) / dif

        eta = long((total - current) / rate)

        (eta_mins, eta_secs) = divmod(eta, 60)

        if eta_mins > 99:

                return '--:--'

        return '%02d:%02d' % (eta_mins, eta_secs)

 

def calc_speed(start, now, bytes):

        dif = now - start

        if bytes == 0 or dif < const_epsilon:

                return 'N/A b'

        return format_bytes(float(bytes) / dif)

 

 

def title_string_touch(title):

        return title.replace(os.sep, '%')

 

cmdl_usage = 'usage: %prog [options] video_url'

cmdl_version = '2008.01.24'

cmdl_parser = optparse.OptionParser(usage=cmdl_usage, version=cmdl_version, conflict_handler='resolve')

cmdl_parser.add_option('-h', '--help', action='help', help='print this help text and exit')

cmdl_parser.add_option('-v', '--version', action='version', help='print program version and exit')

cmdl_parser.add_option('-u', '--username', dest='username', metavar='USERNAME', help='account username')

cmdl_parser.add_option('-p', '--password', dest='password', metavar='PASSWORD', help='account password')

cmdl_parser.add_option('-o', '--output', dest='outfile', metavar='FILE', help='output video file name')

cmdl_parser.add_option('-q', '--quiet', action='store_true', dest='quiet', help='activates quiet mode')

cmdl_parser.add_option('-s', '--simulate', action='store_true', dest='simulate', help='do not download video')

cmdl_parser.add_option('-t', '--title', action='store_true', dest='use_title', help='use title in file name')

cmdl_parser.add_option('-l', '--literal', action='store_true', dest='use_literal', help='use literal title in file name')

cmdl_parser.add_option('-n', '--netrc', action='store_true', dest='use_netrc', help='use .netrc authentication data')

cmdl_parser.add_option('-g', '--get-url', action='store_true', dest='get_url', help='print final video URL only')

cmdl_parser.add_option('-2', '--title-too', action='store_true', dest='get_title', help='used with -g, print title too')

(cmdl_opts, cmdl_args) = cmdl_parser.parse_args()

 

socket.setdefaulttimeout(const_timeout)

 

if len(cmdl_args) != 1:

        cmdl_parser.print_help()

        sys.exit('\n')

video_url_cmdl = cmdl_args[0]

 

video_url_mo = const_video_url_re.match(video_url_cmdl)

if video_url_mo is None:

        sys.exit('Error: URL does not seem to be a youtube video URL. If it is, report a bug.')

video_url_id = video_url_mo.group(2)

video_url = const_video_url_str % video_url_id

 

if cmdl_opts.outfile is not None and (cmdl_opts.simulate or cmdl_opts.get_url):

        sys.stderr.write('Warning: video file name given but will not be used.\n')

 

if cmdl_opts.outfile is not None and (cmdl_opts.use_title or cmdl_opts.use_literal):

        sys.exit('Error: using the video title conflicts with using a given file name.')

 

if cmdl_opts.use_title and cmdl_opts.use_literal:

        sys.exit('Error: cannot use title and literal title at the same time.')

 

if cmdl_opts.quiet and cmdl_opts.get_url:

        sys.exit('Error: cannot be quiet and print final URL at the same time.')

 

if cmdl_opts.username is None and cmdl_opts.password is not None:

        sys.exit('Error: password give but username is missing.')

 

if cmdl_opts.use_netrc and (cmdl_opts.username is not None or cmdl_opts.password is not None):

        sys.exit('Error: cannot use netrc and username/password at the same time.')

 

if cmdl_opts.get_url is None and cmdl_opts.get_title is not None:

        sys.exit('Error: getting title requires getting URL.')

 

account_username = None

account_password = None

 

if cmdl_opts.use_netrc:

        try:

                info = netrc.netrc().authenticators('youtube')

                if info is None:

                        sys.exit('Error: no authenticators for machine youtube.')

                account_username = info[0]

                account_password = info[2]

        except IOError:

                sys.exit('Error: unable to read .netrc file.')

        except netrc.NetrcParseError:

                sys.exit('Error: unable to parse .netrc file.')

else:

        account_username = cmdl_opts.username

        if account_username is not None:

                if cmdl_opts.password is None:

                        account_password = getpass.getpass('Type YouTube password and press return: ')

                else:

                        account_password = cmdl_opts.password

 

if cmdl_opts.outfile is None:

        video_filename = '%s.flv' % video_url_id

else:

        video_filename = cmdl_opts.outfile

 

urllib2.install_opener(urllib2.build_opener(urllib2.ProxyHandler()))

urllib2.install_opener(urllib2.build_opener(urllib2.HTTPCookieProcessor()))

 

if account_username is not None:

        url = const_login_url_str % video_url_id

        post = const_login_post_str % (video_url_id, account_username, account_password)

        download_step(False, 'Logging in', 'unable to log in', url, post)

 

        url = const_age_url_str % video_url_id

        post = const_age_post_str % video_url_id

        download_step(False, 'Confirming age', 'unable to confirm age', url, post)

 

video_webpage = download_step(True, 'Retrieving video webpage', 'unable to retrieve video webpage', video_url)

 

if cmdl_opts.use_title or cmdl_opts.use_literal or cmdl_opts.get_title:

        video_title = extract_step('Extracting video title', 'unable to extract video title', const_video_title_re, video_webpage)

 

video_url_t_param = extract_step('Extracting URL "t" parameter', 'unable to extract URL "t" parameter', const_url_t_param_re, video_webpage)

video_url_real = const_video_url_real_str % (video_url_id, video_url_t_param)

 

if cmdl_opts.use_title or cmdl_opts.use_literal:

        if cmdl_opts.use_title:

                prefix = title_string_norm(video_title)

        else:

                prefix = title_string_touch(video_title)

        video_filename = '%s-%s.flv' % (prefix, video_url_id)

 

if not video_filename.lower().endswith('.flv'):

        sys.stderr.write('Warning: video file name does not end in .flv\n')

 

try:

        cond_print('Requesting video file... ')

        video_data = perform_request(video_url_real)

        cond_print('done.\n')

        cond_print('Video data found at %s\n' % video_data.geturl())

 

        if cmdl_opts.get_title:

                print video_title

 

        if cmdl_opts.get_url:

                print video_data.geturl()

 

        if cmdl_opts.simulate or cmdl_opts.get_url:

                sys.exit()

 

        try:

                video_file = open(video_filename, 'wb')

        except (IOError, OSError):

                sys.exit('Error: unable to open "%s" for writing.' % video_filename)

        try:

                video_len = long(video_data.info()['Content-length'])

                video_len_str = format_bytes(video_len)

        except KeyError:

                video_len = None

                video_len_str = 'N/A'

 

        byte_counter = 0

        block_size = const_initial_block_size

        start_time = time.time()

        while True:

                if video_len is not None:

                        percent = float(byte_counter) / float(video_len) * 100.0

                        percent_str = '%.1f' % percent

                        eta_str = calc_eta(start_time, time.time(), video_len, byte_counter)

                else:

                        percent_str = '---.-'

                        eta_str = '--:--'

                counter = format_bytes(byte_counter)

                speed_str = calc_speed(start_time, time.time(), byte_counter)

                cond_print('\rRetrieving video data: %5s%% (%8s of %s) at %8s/s ETA %s ' % (percent_str, counter, video_len_str, speed_str, eta_str))

 

                before = time.time()

                video_block = video_data.read(block_size)

                after = time.time()

                dl_bytes = len(video_block)

                if dl_bytes == 0:

                        break

                byte_counter += dl_bytes

                video_file.write(video_block)

                block_size = new_block_size(before, after, dl_bytes)

 

        if video_len is not None and byte_counter != video_len:

                error_advice_exit('server did not send the expected ammount of data')

 

        video_file.close()

        cond_print('done.\n')

        cond_print('Video data saved to %s\n' % video_filename)

 

except (urllib2.URLError, ValueError, httplib.HTTPException, TypeError, socket.error):

        cond_print('failed.\n')

        error_advice_exit('unable to download video data')

 

except KeyboardInterrupt:

        sys.exit('\n')

 

sys.exit()