"""
TV information, written by Lurchington 2010
modified by rmmh 2010 && lukeroge 2011
"""

import datetime
from urllib2 import URLError
from zipfile import ZipFile
from cStringIO import StringIO

from lxml import etree
from util import hook, http


base_url = "http://thetvdb.com/api/"


def get_zipped_xml(*args, **kwargs):
    try:
        path = kwargs.pop("path")
    except KeyError:
        raise KeyError("must specify a path for the zipped file to be read")
    zip_buffer = StringIO(http.get(*args, **kwargs))
    return etree.parse(ZipFile(zip_buffer, "r").open(path))


def get_episodes_for_series(seriesname, api_key):
    res = {"error": None, "ended": False, "episodes": None, "name": None}
    # http://thetvdb.com/wiki/index.php/API:GetSeries
    try:
        query = http.get_xml(base_url + 'GetSeries.php', seriesname=seriesname)
    except URLError:
        res["error"] = "Error contacting thetvdb.com."
        return res

    series_id = query.xpath('//seriesid/text()')

    if not series_id:
        res["error"] = "Unknown TV series (using www.thetvdb.com)."
        return res

    series_id = series_id[0]

    try:
        series = get_zipped_xml(base_url + '%s/series/%s/all/en.zip' %
                                    (api_key, series_id), path="en.xml")
    except URLError:
        res["error"] = "Error contacting thetvdb.com."
        return res

    series_name = series.xpath('//SeriesName/text()')[0]

    if series.xpath('//Status/text()')[0] == 'Ended':
        res["ended"] = True

    res["episodes"] = series.xpath('//Episode')
    res["name"] = series_name
    return res


def get_episode_info(episode):
    first_aired = episode.findtext("FirstAired")

    try:
        airdate = datetime.date(*map(int, first_aired.split('-')))
    except (ValueError, TypeError):
        return None

    episode_num = "S%02dE%02d" % (int(episode.findtext("SeasonNumber")),
                                  int(episode.findtext("EpisodeNumber")))

    episode_name = episode.findtext("EpisodeName")
    # in the event of an unannounced episode title, users either leave the
    # field out (None) or fill it with TBA
    if episode_name == "TBA":
        episode_name = None

    episode_desc = '%s' % episode_num
    if episode_name:
        episode_desc += ' - %s' % episode_name
    return (first_aired, airdate, episode_desc)


@hook.command
@hook.command('tv')
def tv_next(inp, bot = None):
    ".tv_next <series> -- get the next episode of <series>"

    api_key = bot.config["api_keys"]["tvdb"]
    episodes = get_episodes_for_series(inp, api_key)

    if episodes["error"]:
        return episodes["error"]

    series_name = episodes["name"]
    ended = episodes["ended"]
    episodes = episodes["episodes"]

    if ended:
        return "%s has ended." % series_name

    next_eps = []
    today = datetime.date.today()

    for episode in reversed(episodes):
        ep_info = get_episode_info(episode)

        if ep_info is None:
            continue

        (first_aired, airdate, episode_desc) = ep_info

        if airdate > today:
            next_eps = ['%s (%s)' % (first_aired, episode_desc)]
        elif airdate == today:
            next_eps = ['Today (%s)' % episode_desc] + next_eps
        else:
            #we're iterating in reverse order with newest episodes last
            #so, as soon as we're past today, break out of loop
            break

    if not next_eps:
        return "There are no new episodes scheduled for %s." % series_name

    if len(next_eps) == 1:
        return "The next episode of %s airs %s." % (series_name, next_eps[0])
    else:
        next_eps = ', '.join(next_eps)
        return "The next episodes of %s: %s." % (series_name, next_eps)


@hook.command
@hook.command('tv_prev')
def tv_last(inp, bot = None):
    ".tv_last <series> -- gets the most recently aired episode of <series>"

    api_key = bot.config["api_keys"]["tvdb"]
    episodes = get_episodes_for_series(inp, api_key)

    if episodes["error"]:
        return episodes["error"]

    series_name = episodes["name"]
    ended = episodes["ended"]
    episodes = episodes["episodes"]

    prev_ep = None
    today = datetime.date.today()

    for episode in reversed(episodes):
        ep_info = get_episode_info(episode)

        if ep_info is None:
            continue

        (first_aired, airdate, episode_desc) = ep_info

        if airdate < today:
            #iterating in reverse order, so the first episode encountered
            #before today was the most recently aired
            prev_ep = '%s (%s)' % (first_aired, episode_desc)
            break

    if not prev_ep:
        return "there are no previously aired episodes for %s" % series_name
    if ended:
        return '%s ended. The last episode aired %s' % (series_name, prev_ep)
    return "the last episode of %s aired %s" % (series_name, prev_ep)