import cherrypy
import dateutil.parser
import requests
import xml.etree.ElementTree as ET
from tools.converters import *
from tools.extractors import extract_yt_initial_data, eu_consent_cookie
from threading import Lock
from cachetools import TTLCache

channel_cache = TTLCache(maxsize=50, ttl=300)
channel_cache_lock = Lock()
channel_latest_cache = TTLCache(maxsize=500, ttl=300)
channel_latest_cache_lock = Lock()

def extract_channel(ucid, second__path="user"):
	cache_key = (ucid, second__path)

	with channel_cache_lock:
		if cache_key in channel_cache:
			return channel_cache[cache_key]

	channel_type = "channel" if len(ucid) == 24 and ucid[:2] == "UC" else second__path
	r = requests.get("https://www.youtube.com/{}/{}/videos?hl=en".format(channel_type, ucid), cookies=eu_consent_cookie())
	r.raise_for_status()
	yt_initial_data = extract_yt_initial_data(r.content.decode("utf8"))

	for alert in yt_initial_data.get("alerts", []):
		alert_text = combine_runs(alert["alertRenderer"]["text"])
		if alert_text == "This channel does not exist.":
			return {
				"error": alert_text,
				"identifier": "NOT_FOUND"
			}
		elif alert_text.startswith("This account has been terminated"):
			return {
				"error": alert_text,
				"identifier": "ACCOUNT_TERMINATED"
			}
		else:
			return {
				"error": alert_text,
				"identifier": "UNKNOWN"
			}

	header = yt_initial_data["header"]["c4TabbedHeaderRenderer"] if "c4TabbedHeaderRenderer" in yt_initial_data["header"] else {}
	channel_metadata = yt_initial_data["metadata"]["channelMetadataRenderer"]

	if header:
		author = header["title"]
		author_id = header["channelId"]
		author_url = header["navigationEndpoint"]["commandMetadata"]["webCommandMetadata"]["url"]
	else:
		author = channel_metadata["title"]
		author_id = channel_metadata["externalId"]
		author_url = channel_metadata["channelUrl"]

	subscriber_count = combine_runs(header["subscriberCountText"]) if "subscriberCountText" in header else "Unknown subscribers"
	description = channel_metadata["description"]
	allowed_regions = channel_metadata["availableCountryCodes"]

	author_banners = []
	if "banner" in header:
		author_banners = header["banner"]["thumbnails"]
		for t in author_banners:
			t["url"] = normalise_url_protocol(t["url"])

	author_thumbnails = []
	avatar = header.get("avatar") or channel_metadata.get("avatar")
	if avatar:
		author_thumbnails = generate_full_author_thumbnails(avatar["thumbnails"])

	latest_videos = []
	tabs = yt_initial_data["contents"]["twoColumnBrowseResultsRenderer"]["tabs"]
	try:
		videos_tab = next(tab["tabRenderer"] for tab in tabs if tab.get("tabRenderer", {}).get("title") == "Videos")
		tab_parts = videos_tab["content"]
	except StopIteration:
		tab_parts = {}

	# check that the channel actually has videos - this may be replaced
	# with messageRenderer.text.simpleText == "This channel has no videos."
	if "richGridRenderer" in tab_parts:
		videos = (
			v["richItemRenderer"]["content"]["videoRenderer"] for v in tab_parts["richGridRenderer"]["contents"] if "richItemRenderer" in v
		)
		for v in videos:
			live = False
			is_upcoming = False
			length_text = "UNKNOWN"
			length_seconds = -1
			for o in v["thumbnailOverlays"]:
				if "thumbnailOverlayTimeStatusRenderer" in o:
					length_text = combine_runs(o["thumbnailOverlayTimeStatusRenderer"]["text"])
					length_text_style = o["thumbnailOverlayTimeStatusRenderer"]["style"]
					if length_text_style == "DEFAULT":
						length_seconds = length_text_to_seconds(length_text)
					elif length_text_style == "LIVE":
						live = True
					elif length_text_style == "UPCOMING":
						is_upcoming = True
			published = 0
			published_text = "Live now"
			premiere_timestamp = None
			if "publishedTimeText" in v:
				published_text = v["publishedTimeText"]["simpleText"]
				published = past_text_to_time(published_text)
			if "upcomingEventData" in v:
				premiere_timestamp = v["upcomingEventData"]["startTime"]
				published_text = time_to_past_text(int(premiere_timestamp))

			view_count_text = combine_runs(v["viewCountText"]) if "viewCountText" in v else None
			view_count_text_short = combine_runs(v["shortViewCountText"]) if "shortViewCountText" in v else None

			latest_videos.append({
				"type": "video",
				"title": combine_runs(v["title"]),
				"videoId": v["videoId"],
				"author": author,
				"authorId": author_id,
				"authorUrl": author_url,
				"videoThumbnails": generate_video_thumbnails(v["videoId"]),
				"description": "",
				"descriptionHtml": "",
				"viewCount": view_count_text_to_number(view_count_text),
				"second__viewCountText": view_count_text,
				"second__viewCountTextShort": view_count_text_short,
				"published": published,
				"publishedText": published_text,
				"lengthSeconds": length_seconds,
				"second__lengthText": length_text,
				"liveNow": live,
				"paid": None,
				"premium": None,
				"isUpcoming": is_upcoming,
				"premiereTimestamp": premiere_timestamp
			})

	channel = {
		"author": author,
		"authorId": author_id,
		"authorUrl": author_url,
		"authorBanners": author_banners,
		"authorThumbnails": author_thumbnails,
		"subCount": uncompress_counter(subscriber_count.split(" ")[0]),
		"second__subCountText": subscriber_count,
		"totalViews": None,
		"joined": None,
		"paid": None,
		"autoGenerated": None,
		"isFamilyFriendly": None,
		"description": description,
		"descriptionHtml": add_html_links(escape_html_textcontent(description)),
		"allowedRegions": allowed_regions,
		"latestVideos": latest_videos,
		"relatedChannels": []
	}

	with channel_cache_lock:
		channel_cache[cache_key] = channel

	return channel

def extract_channel_videos(ucid, second__path="channel"):
	channel = extract_channel(ucid, second__path)
	if "error" in channel:
		return channel
	else:
		return channel["latestVideos"]

def extract_channel_latest(ucid):
	with channel_latest_cache_lock:
		if ucid in channel_latest_cache:
			return channel_latest_cache[ucid]

	r = requests.get("https://www.youtube.com/feeds/videos.xml?channel_id={}".format(ucid))
	if r.status_code == 404:
		cherrypy.response.status = 404
		return {
			"error": "This channel does not exist.",
			"identifier": "NOT_FOUND"
		}

	feed = ET.fromstring(r.content)
	author_container = feed.find("{http://www.w3.org/2005/Atom}author")
	author = author_container.find("{http://www.w3.org/2005/Atom}name").text
	author_url = author_container.find("{http://www.w3.org/2005/Atom}uri").text
	channel_id = feed.find("{http://www.youtube.com/xml/schemas/2015}channelId").text
	results = []
	missing_published = False
	for entry in feed.findall("{http://www.w3.org/2005/Atom}entry"):
		id = entry.find("{http://www.youtube.com/xml/schemas/2015}videoId").text
		video_channel_id = entry.find("{http://www.youtube.com/xml/schemas/2015}channelId").text or channel_id
		if len(video_channel_id) == 22 and not video.startswith("UC"):
			video_channel_id = "UC" + video_channel_id
		media_group = entry.find("{http://search.yahoo.com/mrss/}group")
		description = media_group.find("{http://search.yahoo.com/mrss/}description").text or ""
		media_community = media_group.find("{http://search.yahoo.com/mrss/}community")
		published_entry = entry.find("{http://www.w3.org/2005/Atom}published")
		if published_entry is not None: # sometimes youtube does not provide published dates, no idea why.
			published = int(dateutil.parser.isoparse(published_entry.text).timestamp())
			results.append({
				"type": "video",
				"title": entry.find("{http://www.w3.org/2005/Atom}title").text,
				"videoId": id,
				"author": author,
				"authorId": video_channel_id,
				"authorUrl": author_url,
				"videoThumbnails": generate_video_thumbnails(id),
				"description": description,
				"descriptionHtml": add_html_links(escape_html_textcontent(description)),
				"viewCount": int(media_community.find("{http://search.yahoo.com/mrss/}statistics").attrib["views"]),
				"published": published,
				"publishedText": time_to_past_text(published),
				"lengthSeconds": None,
				"liveNow": None,
				"paid": None,
				"premium": None,
				"isUpcoming": None
			})
		else:
			missing_published = True

	if len(results) == 0 and missing_published: # no results due to all missing published
		cherrypy.response.status = 503
		return {
			"error": "YouTube did not provide published dates for any feed items. This is usually temporary - refresh in a few minutes.",
			"identifier": "PUBLISHED_DATES_NOT_PROVIDED"
		}

	with channel_latest_cache_lock:
		channel_latest_cache[ucid] = results

	return results