import itertools
import os
import qwarc
import qwarc.utils


responseHandler = qwarc.utils.handle_response_limit_error_retries(5)


class LiveChatReplay(qwarc.Item):
	itemType = 'chat-replay'
	# itemValue = '{videoId}'

	@classmethod
	def generate(cls):
		yield os.environ['YOUTUBE_VIDEOID']

	async def process(self):
		response, _ = await self.fetch(f'https://www.youtube.com/watch?v={self.itemValue}&disable_polymer=1', responseHandler = responseHandler)
		if not response or response.status != 200:
			self.logger.error('Could not fetch video page')
			return
		contents = await response.read()
		conversationBarPos = contents.find(b'\\"conversationBar\\":{')
		if conversationBarPos < 0:
			self.logger.error('Could not find conversation bar')
			return

		# No regerts
		openParens = 0
		for pos in itertools.count(start = conversationBarPos + 20):
			char = contents[pos:pos+1]
			if char in (b'{', b'['):
				openParens += 1
			elif char in (b'}', b']'):
				openParens -= 1
			if openParens == 0:
				break
		conversationBar = contents[conversationBarPos + 20 : pos]
		for continuation in qwarc.utils.str_get_all_between(conversationBar, b'\\"continuation\\":\\"', b'\\"'):
			if not continuation or continuation.lstrip(b'0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_-') not in (b'', b'%3D', b'%3D%3D'):
				self.logger.warning('Skipping unexpected continuation value: {continuation!r}')
				continue
			cont = continuation
			while True:
				page, _ = await self.fetch(f'https://www.youtube.com/live_chat_replay?continuation={cont.decode("ascii")}', responseHandler = responseHandler)
				if not page or page.status != 200:
					self.logger.error(f'Could not fetch continuation {cont!r}')
					break
				pageContents = await page.read()
				contBlock = qwarc.utils.str_get_between(pageContents, b'"liveChatReplayContinuationData":', b'}')
				if not contBlock:
					break
				cont = qwarc.utils.str_get_between(contBlock, b'"continuation":"', b'"')
				if not cont:
					break
				if cont.lstrip(b'0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_-') not in (b'', b'%3D', b'%3D%3D'):
					self.logger.warning(f'Skipping unexpected cont value: {cont!r}')


specDependencies = qwarc.utils.SpecDependencies(extra = (('videoId', os.environ['YOUTUBE_VIDEOID']),))