fix: update innertube clients and fix HLS/DASH quality switching

- Update innertube client versions to match yt-dlp (android 21.02.35,
  ios 21.02.3, web 2.20260114.08.00, android_vr 1.65.10)
- Remove obsolete clients (android-test-suite, ios_vr)
- Replace tv_embedded with TVHTML5_SIMPLY (cn 75)
- Add new clients: web_embedded, mweb, tv
- Fix HLS freeze on quality switch: use nextLevel instead of
  currentLevel, handle bufferStalledError, stream proxy segments
  instead of buffering in memory
- Populate DASH quality selector with actual sources (no Auto)
- Render quality-select empty in template, let JS populate per mode

youtube/util.py

@@ -23,6 +23,9 @@ import stem
 import stem.control
 import traceback
 
+from youtube.yt_data_extract.common import concat_or_none
+from youtube import constants
+
 logger = logging.getLogger(__name__)
 
 # The trouble with the requests library: It ships its own certificate bundle via certifi
@@ -468,11 +471,11 @@ def head(url, use_tor=False, report_text=None, max_redirects=10):
         print(f'{report_text}    Latency: {round(time.monotonic() - start_time, 3)}')
     return response
 
-mobile_user_agent = 'Mozilla/5.0 (Linux; Android 7.0; Redmi Note 4 Build/NRD90M) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Mobile Safari/537.36'
-mobile_ua = (('User-Agent', mobile_user_agent),)
-desktop_user_agent = 'Mozilla/5.0 (Windows NT 6.1; rv:52.0) Gecko/20100101 Firefox/52.0'
-desktop_ua = (('User-Agent', desktop_user_agent),)
-json_header = (('Content-Type', 'application/json'),)
+mobile_user_agent = constants.MOBILE_USER_AGENT
+mobile_ua = constants.mobile_ua
+desktop_user_agent = constants.desktop_user_agent
+desktop_ua = constants.desktop_ua
+json_header = constants.json_header
 desktop_xhr_headers = (
     ('Accept', '*/*'),
     ('Accept-Language', 'en-US,en;q=0.5'),
@@ -641,7 +644,7 @@ def update_query_string(query_string, items):
     return urllib.parse.urlencode(parameters, doseq=True)
 
 
-YOUTUBE_DOMAINS = ('youtube.com', 'youtu.be', 'youtube-nocookie.com')
+YOUTUBE_DOMAINS = constants.YOUTUBE_DOMAINS
 YOUTUBE_URL_RE_STR = r'https?://(?:[a-zA-Z0-9_-]*\.)?(?:'
 YOUTUBE_URL_RE_STR += r'|'.join(map(re.escape, YOUTUBE_DOMAINS))
 YOUTUBE_URL_RE_STR += r')(?:/[^"]*)?'
@@ -668,16 +671,6 @@ def left_remove(string, substring):
     return string
 
 
-def concat_or_none(*strings):
-    '''Concatenates strings. Returns None if any of the arguments are None'''
-    result = ''
-    for string in strings:
-        if string is None:
-            return None
-        result += string
-    return result
-
-
 def prefix_urls(item):
     if settings.proxy_images:
         try:
@@ -726,24 +719,8 @@ def check_gevent_exceptions(*tasks):
 
 
 # https://stackoverflow.com/a/62888
-replacement_map = collections.OrderedDict([
-    ('<', '_'),
-    ('>', '_'),
-    (': ', ' - '),
-    (':', '-'),
-    ('"', "'"),
-    ('/', '_'),
-    ('\\', '_'),
-    ('|', '-'),
-    ('?', ''),
-    ('*', '_'),
-    ('\t', ' '),
-])
-
-DOS_names = {'con', 'prn', 'aux', 'nul', 'com0', 'com1', 'com2', 'com3',
-             'com4', 'com5', 'com6', 'com7', 'com8', 'com9', 'lpt0',
-             'lpt1', 'lpt2', 'lpt3', 'lpt4', 'lpt5', 'lpt6', 'lpt7',
-             'lpt8', 'lpt9'}
+replacement_map = constants.REPLACEMENT_MAP
+DOS_names = constants.DOS_RESERVED_NAMES
 
 
 def to_valid_filename(name):
@@ -785,143 +762,7 @@ def to_valid_filename(name):
     return name
 
 
-# https://github.com/yt-dlp/yt-dlp/blob/master/yt_dlp/extractor/youtube.py#L72
-INNERTUBE_CLIENTS = {
-    'android': {
-        'INNERTUBE_API_KEY': 'AIzaSyA8eiZmM1FaDVjRy-df2KTyQ_vz_yYM39w',
-        'INNERTUBE_CONTEXT': {
-            'client': {
-                'hl': 'en',
-                'gl': 'US',
-                'clientName': 'ANDROID',
-                'clientVersion': '19.09.36',
-                'osName': 'Android',
-                'osVersion': '12',
-                'androidSdkVersion': 31,
-                'platform': 'MOBILE',
-                'userAgent': 'com.google.android.youtube/19.09.36 (Linux; U; Android 12; US) gzip'
-            },
-            # https://github.com/yt-dlp/yt-dlp/pull/575#issuecomment-887739287
-            #'thirdParty': {
-            #    'embedUrl': 'https://google.com',  # Can be any valid URL
-            #}
-        },
-        'INNERTUBE_CONTEXT_CLIENT_NAME': 3,
-        'REQUIRE_JS_PLAYER': False,
-    },
-
-    'android-test-suite': {
-        'INNERTUBE_API_KEY': 'AIzaSyA8eiZmM1FaDVjRy-df2KTyQ_vz_yYM39w',
-        'INNERTUBE_CONTEXT': {
-            'client': {
-                'hl': 'en',
-                'gl': 'US',
-                'clientName': 'ANDROID_TESTSUITE',
-                'clientVersion': '1.9',
-                'osName': 'Android',
-                'osVersion': '12',
-                'androidSdkVersion': 31,
-                'platform': 'MOBILE',
-                'userAgent': 'com.google.android.youtube/1.9 (Linux; U; Android 12; US) gzip'
-            },
-            # https://github.com/yt-dlp/yt-dlp/pull/575#issuecomment-887739287
-            #'thirdParty': {
-            #    'embedUrl': 'https://google.com',  # Can be any valid URL
-            #}
-        },
-        'INNERTUBE_CONTEXT_CLIENT_NAME': 3,
-        'REQUIRE_JS_PLAYER': False,
-    },
-
-    'ios': {
-        'INNERTUBE_API_KEY': 'AIzaSyB-63vPrdThhKuerbB2N_l7Kwwcxj6yUAc',
-        'INNERTUBE_CONTEXT': {
-            'client': {
-                'hl': 'en',
-                'gl': 'US',
-                'clientName': 'IOS',
-                'clientVersion': '21.03.2',
-                'deviceMake': 'Apple',
-                'deviceModel': 'iPhone16,2',
-                'osName': 'iPhone',
-                'osVersion': '18.7.2.22H124',
-                'userAgent': 'com.google.ios.youtube/21.03.2 (iPhone16,2; U; CPU iOS 18_7_2 like Mac OS X)'
-            }
-        },
-        'INNERTUBE_CONTEXT_CLIENT_NAME': 5,
-        'REQUIRE_JS_PLAYER': False
-    },
-
-    # This client can access age restricted videos (unless the uploader has disabled the 'allow embedding' option)
-    # See: https://github.com/zerodytrash/YouTube-Internal-Clients
-    'tv_embedded': {
-        'INNERTUBE_API_KEY': 'AIzaSyAO_FJ2SlqU8Q4STEHLGCilw_Y9_11qcW8',
-        'INNERTUBE_CONTEXT': {
-            'client': {
-                'hl': 'en',
-                'gl': 'US',
-                'clientName': 'TVHTML5_SIMPLY_EMBEDDED_PLAYER',
-                'clientVersion': '2.0',
-                'clientScreen': 'EMBED',
-            },
-            # https://github.com/yt-dlp/yt-dlp/pull/575#issuecomment-887739287
-            'thirdParty': {
-                'embedUrl': 'https://google.com',  # Can be any valid URL
-            }
-
-        },
-        'INNERTUBE_CONTEXT_CLIENT_NAME': 85,
-        'REQUIRE_JS_PLAYER': True,
-    },
-
-    'web': {
-        'INNERTUBE_API_KEY': 'AIzaSyAO_FJ2SlqU8Q4STEHLGCilw_Y9_11qcW8',
-        'INNERTUBE_CONTEXT': {
-            'client': {
-                'clientName': 'WEB',
-                'clientVersion': '2.20220801.00.00',
-                'userAgent': desktop_user_agent,
-            }
-        },
-        'INNERTUBE_CONTEXT_CLIENT_NAME': 1
-    },
-    'android_vr': {
-        'INNERTUBE_API_KEY': 'AIzaSyA8eiZmM1FaDVjRy-df2KTyQ_vz_yYM39w',
-        'INNERTUBE_CONTEXT': {
-            'client': {
-                'clientName': 'ANDROID_VR',
-                'clientVersion': '1.60.19',
-                'deviceMake': 'Oculus',
-                'deviceModel': 'Quest 3',
-                'androidSdkVersion': 32,
-                'userAgent': 'com.google.android.apps.youtube.vr.oculus/1.60.19 (Linux; U; Android 12L; eureka-user Build/SQ3A.220605.009.A1) gzip',
-                'osName': 'Android',
-                'osVersion': '12L',
-            },
-        },
-        'INNERTUBE_CONTEXT_CLIENT_NAME': 28,
-        'REQUIRE_JS_PLAYER': False,
-    },
-
-    'ios_vr': {
-        'INNERTUBE_API_KEY': 'AIzaSyA8eiZmM1FaDVjRy-df2KTyQ_vz_yYM39w',
-        'INNERTUBE_CONTEXT': {
-            'client': {
-                'hl': 'en',
-                'gl': 'US',
-                'clientName': 'IOS_VR',
-                'clientVersion': '1.0',
-                'deviceMake': 'Apple',
-                'deviceModel': 'iPhone16,2',
-                'osName': 'iPhone',
-                'osVersion': '18.7.2.22H124',
-                'userAgent': 'com.google.ios.youtube/1.0 (iPhone16,2; U; CPU iOS 18_7_2 like Mac OS X)'
-            }
-        },
-        'INNERTUBE_CONTEXT_CLIENT_NAME': 5,
-        'REQUIRE_JS_PLAYER': False
-    },
-}
+INNERTUBE_CLIENTS = constants.INNERTUBE_CLIENTS
 
 def get_visitor_data():
     visitor_data = None