#!/usr/bin/env python3
"""
Tools for updating and extracting data from the Redis database.
"""
import re
import json
import time

import bs4
import redis
import requests

import config

_r = redis.Redis(
	config.REDIS_HOST,
	config.REDIS_PORT,
)

def scrape_feed(feed_url):
	"""Scrapes an RSS feed and extract all relevant data from it."""
	try:
		res = requests.get(feed_url)
		res.raise_for_status()
	except requests.exceptions.RequestException as e:
		# TODO: log the error
		return
	encoding = re.search(r'encoding="(.*)"', res.text)
	if encoding:
		encoding = encoding.group(1)
	else:
		encoding = 'utf-8'
	soup = bs4.BeautifulSoup(res.content, 'xml', from_encoding=encoding)

	if "factorio.com" in feed_url: # because screw making it generic
		return scrape_factorio(soup)
	elif "zombieknight" in feed_url:
		return scrape_zombie_knight(soup)

	meta = {}
	meta['title'] = soup.title.text
	meta['html_url'] = soup.find("link", href="").text
	meta['description'] = soup.description.text
	
	entries = soup.find_all('item')
	feed_entries = []
	for entry in entries[:20]:
		entry_dict = {}
		entry_dict['title'] = entry.title.text
		entry_dict['link'] = entry.link.text
		try:
			date = entry.pubDate.text
			try:
				date = time.strptime(date, '%a, %d %b %Y %H:%M:%S %z')
			except ValueError:
				date = time.strptime(date, '%a, %d %b %Y %H:%M:%S %Z')
			entry_dict['date'] = time.strftime('%Y-%m-%d', date)
		except AttributeError:
			entry_dict['date'] = ""
		entry_dict['description'] = entry.description.text[:200]
		# TODO: html sanitation
		feed_entries.append(entry_dict)
	feed = {'meta': meta, 'entries': feed_entries}
	return feed


def scrape_zombie_knight(soup):
	"""Handles the special case that is Zombie Knight Saga."""
	meta = {}
	meta['title'] = soup.title.text
	meta['html_url'] = soup.find("link", rel='alternate').get('href')
	meta['description'] = soup.subtitle.text

	entries = soup.find_all('entry')
	feed_entries = []
	for entry in entries[:20]:
		entry_dict = {}
		entry_dict['title'] = entry.title.text
		entry_dict['link'] = entry.find("link", rel='alternate').get('href')
		date = entry.updated.text
		date = "".join(re.search("(.*)\.\d{3}(.\d{2}):(\d{2})", date).groups())
		date = time.strptime(date, '%Y-%m-%dT%H:%M:%S%z')
		entry_dict['date'] = time.strftime('%Y-%m-%d', date)
		entry_dict['description'] = entry.content.text[:200]
		# TODO: html sanitation
		feed_entries.append(entry_dict)
	feed = {'meta': meta, 'entries': feed_entries}
	return feed


def scrape_factorio(soup):
	"""Handles the special case that is the Factorio development blog."""
	meta = {}
	meta['title'] = "Factorio"
	meta['html_url'] = soup.find('link').get('href')
	meta['description'] = soup.title.text

	entries = soup.find_all('entry')
	feed_entries = []
	for entry in entries[:20]:
		entry_dict = {}
		entry_dict['title'] = entry.title.text
		entry_dict['link'] = entry.find('link').get('href')
		date = entry.updated.text
		date = time.strptime(date[:-3]+date[-2:], '%Y-%m-%dT%H:%M:%S%z')
		entry_dict['date'] = time.strftime('%Y-%m-%d', date)
		entry_dict['description'] = entry.content.text[:200]
		# TODO: html sanitation
		feed_entries.append(entry_dict)
	feed = {'meta': meta, 'entries': feed_entries}
	return feed


def update_feed(feed_url):
	"""Updates the given feed_id."""
	feed = scrape_feed(feed_url)
	_r.set(feed_url, json.dumps(feed))


def update_all_feeds():
	"""Updates all feeds being watched."""
	for feed_url in config.FEEDS:
		#print(feed_url)
		update_feed(feed_url)


def get_feed(feed_url):
	"""Returns all stored information about the feed."""
	return json.loads(_r.get(feed_url))