# Author: Nic Wolfe <nic@wolfeden.ca>
# URL: http://code.google.com/p/sickbeard/
#
# This file is part of Sick Beard.
#
# Sick Beard is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Sick Beard is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Sick Beard.  If not, see <http://www.gnu.org/licenses/>.

from __future__ import with_statement

import datetime
import os
import sys
import re
import urllib2
import copy
import itertools
import operator
import collections

import sickbeard

from sickbeard import helpers, classes, logger, db
from sickbeard.common import Quality, MULTI_EP_RESULT, SEASON_RESULT#, SEED_POLICY_TIME, SEED_POLICY_RATIO
from sickbeard import tvcache
from sickbeard import encodingKludge as ek
from sickbeard.exceptions import ex
from lib.hachoir_parser import createParser
from sickbeard.name_parser.parser import NameParser, InvalidNameException
from sickbeard import scene_numbering
from sickbeard.common import Quality, Overview

class GenericProvider:

    NZB = "nzb"
    TORRENT = "torrent"

    def __init__(self, name):

        # these need to be set in the subclass
        self.providerType = None
        self.name = name
        self.url = ''

        self.supportsBacklog = False

        self.cache = tvcache.TVCache(self)

    def getID(self):
        return GenericProvider.makeID(self.name)

    @staticmethod
    def makeID(name):
         return re.sub("[^\w\d_]", "_", name.strip().lower())

    def imageName(self):
        return self.getID() + '.png'

    def _checkAuth(self):
        return

    def isActive(self):
        if self.providerType == GenericProvider.NZB and sickbeard.USE_NZBS:
            return self.isEnabled()
        elif self.providerType == GenericProvider.TORRENT and sickbeard.USE_TORRENTS:
            return self.isEnabled()
        else:
            return False

    def isEnabled(self):
        """
        This should be overridden and should return the config setting eg. sickbeard.MYPROVIDER
        """
        return False

    def getResult(self, episodes):
        """
        Returns a result of the correct type for this provider
        """

        if self.providerType == GenericProvider.NZB:
            result = classes.NZBSearchResult(episodes)
        elif self.providerType == GenericProvider.TORRENT:
            result = classes.TorrentSearchResult(episodes)
        else:
            result = classes.SearchResult(episodes)
        
        result.provider = self    
            
        return result

    def getURL(self, url, post_data=None, headers=None):
        """
        By default this is just a simple urlopen call but this method should be overridden
        for providers with special URL requirements (like cookies)
        """

        if not headers:
            headers = []

        data = helpers.getURL(url, post_data, headers)

        if not data:
            logger.log(u"Error loading " + self.name + " URL: " + url, logger.ERROR)
            return None

        return data

    def downloadResult(self, result):
        """
        Save the result to disk.
        """

        logger.log(u"Downloading a result from " + self.name+" at " + result.url)

        data = self.getURL(result.url)

        if data == None:
            return False

        # use the appropriate watch folder
        if self.providerType == GenericProvider.NZB:
            saveDir = sickbeard.NZB_DIR
            writeMode = 'w'
        elif self.providerType == GenericProvider.TORRENT:
            saveDir = sickbeard.TORRENT_DIR
            writeMode = 'wb'
        else:
            return False

        # use the result name as the filename
        file_name = ek.ek(os.path.join, saveDir, helpers.sanitizeFileName(result.name) + '.' + self.providerType)

        logger.log(u"Saving to " + file_name, logger.DEBUG)

        try:
            with open(file_name, writeMode) as fileOut:
                fileOut.write(data)
            helpers.chmodAsParent(file_name)
        except EnvironmentError, e:
            logger.log("Unable to save the file: " + ex(e), logger.ERROR)
            return False

        # as long as it's a valid download then consider it a successful snatch
        return self._verify_download(file_name)

    def _verify_download(self, file_name=None):
        """
        Checks the saved file to see if it was actually valid, if not then consider the download a failure.
        """

        # primitive verification of torrents, just make sure we didn't get a text file or something
        if self.providerType == GenericProvider.TORRENT:
            parser = createParser(file_name)
            if parser:
                mime_type = parser._getMimeType()
                try:
                    parser.stream._input.close()
                except:
                    pass
                if mime_type != 'application/x-bittorrent':
                    logger.log(u"Result is not a valid torrent file", logger.WARNING)
                    return False

        return True

    def searchRSS(self):

        self._checkAuth()
        self.cache.updateCache()

        return self.cache.findNeededEpisodes()

    def getQuality(self, item):
        """
        Figures out the quality of the given RSS item node
        
        item: An elementtree.ElementTree element representing the <item> tag of the RSS feed
        
        Returns a Quality value obtained from the node's data 
        """
        (title, url) = self._get_title_and_url(item) # @UnusedVariable
        quality = Quality.sceneQuality(title)
        return quality

    def _doSearch(self):
        return []

    def _get_season_search_strings(self, show, season, wantedEp, searchSeason=False):
        return []

    def _get_episode_search_strings(self, ep_obj):
        return []
    
    def _get_title_and_url(self, item):
        """
        Retrieves the title and URL data from the item XML node

        item: An elementtree.ElementTree element representing the <item> tag of the RSS feed

        Returns: A tuple containing two strings representing title and URL respectively
        """
        title = helpers.get_xml_text(item.find('title'))
        if title:
            title = title.replace(' ', '.')

        url = helpers.get_xml_text(item.find('link'))
        if url:
            url = url.replace('&amp;', '&')
            
        return (title, url)
        
    def findEpisode(self, episode, manualSearch=False):

        self._checkAuth()

        # XEM episode scene numbering
        sceneEpisode = copy.copy(episode)
        sceneEpisode.convertToSceneNumbering()

        logger.log(u'Searching "%s" for "%s" as "%s"'
                   % (self.name, episode.prettyName() , sceneEpisode.prettyName()))

        self.cache.updateCache()
        results = self.cache.searchCache(episode, manualSearch)
        logger.log(u"Cache results: " + str(results), logger.DEBUG)
        logger.log(u"manualSearch: " + str(manualSearch), logger.DEBUG)

        # if we got some results then use them no matter what.
        # OR
        # return anyway unless we're doing a manual search
        if results or not manualSearch:
            return results

        itemList = []

        for cur_search_string in self._get_episode_search_strings(sceneEpisode):
            itemList += self._doSearch(cur_search_string, show=episode.show)

        for item in itemList:

            (title, url) = self._get_title_and_url(item)

            # parse the file name
            try:
                myParser = NameParser(False)
                parse_result = myParser.parse(title, True)
            except InvalidNameException:
                logger.log(u"Unable to parse the filename " + title + " into a valid episode", logger.WARNING)
                continue

            if episode.show.air_by_date:
                if parse_result.air_date != episode.airdate:
                    logger.log(u"Episode " + title + " didn't air on " + str(episode.airdate) + ", skipping it", logger.DEBUG)
                    continue
            elif parse_result.season_number != episode.season or episode.episode not in parse_result.episode_numbers:
                logger.log(u"Episode " + title + " isn't " + str(episode.season) + "x" + str(episode.episode) + ", skipping it", logger.DEBUG)
                continue

            quality = self.getQuality(item)

            if not episode.show.wantEpisode(episode.season, episode.episode, quality, manualSearch):
                logger.log(u"Ignoring result " + title + " because we don't want an episode that is " + Quality.qualityStrings[quality], logger.DEBUG)
                continue

            logger.log(u"Found result " + title + " at " + url, logger.DEBUG)

            result = self.getResult([episode])
            result.url = url
            result.name = title
            result.quality = quality
            result.provider = self
            result.content = None 
            
            results.append(result)

        return results

    def findSeasonResults(self, show, season):

        itemList = []
        results = {}
        sceneSeasons = {}
        searchSeason = False


        # convert wanted seasons and episodes to XEM scene numbering
        seasonEp = show.getAllEpisodes(season)
        wantedEp = [x for x in seasonEp if show.getOverview(x.status) in (Overview.WANTED, Overview.QUAL)]
        map(lambda x: x.convertToSceneNumbering(), wantedEp)
        for x in wantedEp: sceneSeasons.setdefault(x.season,[]).append(x)

        if wantedEp == seasonEp and not show.air_by_date:
            searchSeason = True

        for sceneSeason,sceneEpisodes in sceneSeasons.iteritems():
            for curString in self._get_season_search_strings(show, sceneSeason, sceneEpisodes, searchSeason):
                itemList += self._doSearch(curString)

        for item in itemList:

            (title, url) = self._get_title_and_url(item)

            quality = self.getQuality(item)

            # parse the file name
            try:
                myParser = NameParser(False)
                parse_result = myParser.parse(title, True)
            except InvalidNameException:
                logger.log(u"Unable to parse the filename " + title + " into a valid episode", logger.WARNING)
                continue

            if not show.air_by_date:
                # this check is meaningless for non-season searches
                if (parse_result.season_number != None and parse_result.season_number != season) or (parse_result.season_number == None and season != 1):
                    logger.log(u"The result " + title + " doesn't seem to be a valid episode for season " + str(season) + ", ignoring", logger.DEBUG)
                    continue

                # we just use the existing info for normal searches
                actual_season = season
                actual_episodes = parse_result.episode_numbers

            else:
                if not parse_result.air_by_date:
                    logger.log(u"This is supposed to be an air-by-date search but the result "+title+" didn't parse as one, skipping it", logger.DEBUG)
                    continue

                myDB = db.DBConnection()
                sql_results = myDB.select("SELECT season, episode FROM tv_episodes WHERE showid = ? AND airdate = ?", [show.indexerid, parse_result.air_date.toordinal()])

                if len(sql_results) != 1:
                    logger.log(u"Tried to look up the date for the episode "+title+" but the database didn't give proper results, skipping it", logger.WARNING)
                    continue

                actual_season = int(sql_results[0]["season"])
                actual_episodes = [int(sql_results[0]["episode"])]

            # make sure we want the episode
            wantEp = True
            for epNo in actual_episodes:
                if not show.wantEpisode(actual_season, epNo, quality):
                    wantEp = False
                    break

            if not wantEp:
                logger.log(u"Ignoring result " + title + " because we don't want an episode that is " + Quality.qualityStrings[quality], logger.DEBUG)
                continue

            logger.log(u"Found result " + title + " at " + url, logger.DEBUG)

            # make a result object
            epObj = []
            for curEp in actual_episodes:
                epObj.append(show.getEpisode(actual_season, curEp))

            result = self.getResult(epObj)
            result.url = url
            result.name = title
            result.quality = quality
            result.provider = self
            result.content = None

            if len(epObj) == 1:
                epNum = epObj[0].episode
            elif len(epObj) > 1:
                epNum = MULTI_EP_RESULT
                logger.log(u"Separating multi-episode result to check for later - result contains episodes: " + str(parse_result.episode_numbers), logger.DEBUG)
            elif len(epObj) == 0:
                epNum = SEASON_RESULT
                result.extraInfo = [show]
                logger.log(u"Separating full season result to check for later", logger.DEBUG)

            if epNum in results:
                results[epNum].append(result)
            else:
                results[epNum] = [result]

        return results

    def findPropers(self, search_date=None):

        results = self.cache.listPropers(search_date)

        return [classes.Proper(x['name'], x['url'], datetime.datetime.fromtimestamp(x['time'])) for x in results]


class NZBProvider(GenericProvider):

    def __init__(self, name):

        GenericProvider.__init__(self, name)

        self.providerType = GenericProvider.NZB

class TorrentProvider(GenericProvider):

    def __init__(self, name):

        GenericProvider.__init__(self, name)

        self.providerType = GenericProvider.TORRENT
        
#        self.option = {SEED_POLICY_TIME : '',
#                       SEED_POLICY_RATIO: '',
#                       'PROCESS_METHOD': ''
#                       }
    
#    def get_provider_options(self):
#        pass
#    
#    def set_provider_options(self):
#        self.option[SEED_POLICY_TIME] + '|' + self.option[SEED_POLICY_RATIO] + '|' + self.option['PROCESS_METHOD']