# Author: Nic Wolfe <nic@wolfeden.ca>
# URL: http://code.google.com/p/sickbeard/
#
# This file is part of SickRage.
#
# SickRage 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.
#
# SickRage 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 SickRage.  If not, see <http://www.gnu.org/licenses/>.

from __future__ import with_statement

import requests

import xml.etree.cElementTree as etree
import xml.etree
import re

from sickbeard import logger, classes, helpers
from sickbeard.common import Quality
from sickbeard import encodingKludge as ek
from sickbeard.exceptions import ex

from name_parser.parser import NameParser, InvalidNameException, InvalidShowException

def getSeasonNZBs(name, urlData, season):
    try:
        showXML = etree.ElementTree(etree.XML(urlData))
    except SyntaxError:
        logger.log(u"Unable to parse the XML of " + name + ", not splitting it", logger.ERROR)
        return ({}, '')

    filename = name.replace(".nzb", "")

    nzbElement = showXML.getroot()

    regex = '([\w\._\ ]+)[\. ]S%02d[\. ]([\w\._\-\ ]+)[\- ]([\w_\-\ ]+?)' % season

    sceneNameMatch = re.search(regex, filename, re.I)
    if sceneNameMatch:
        showName, qualitySection, groupName = sceneNameMatch.groups()  # @UnusedVariable
    else:
        logger.log(u"Unable to parse " + name + " into a scene name. If it's a valid one log a bug.", logger.ERROR)
        return ({}, '')

    regex = '(' + re.escape(showName) + '\.S%02d(?:[E0-9]+)\.[\w\._]+\-\w+' % season + ')'
    regex = regex.replace(' ', '.')

    epFiles = {}
    xmlns = None

    for curFile in nzbElement.getchildren():
        xmlnsMatch = re.match("\{(http:\/\/[A-Za-z0-9_\.\/]+\/nzb)\}file", curFile.tag)
        if not xmlnsMatch:
            continue
        else:
            xmlns = xmlnsMatch.group(1)
        match = re.search(regex, curFile.get("subject"), re.I)
        if not match:
            #print curFile.get("subject"), "doesn't match", regex
            continue
        curEp = match.group(1)
        if curEp not in epFiles:
            epFiles[curEp] = [curFile]
        else:
            epFiles[curEp].append(curFile)

    return (epFiles, xmlns)


def createNZBString(fileElements, xmlns):
    rootElement = etree.Element("nzb")
    if xmlns:
        rootElement.set("xmlns", xmlns)

    for curFile in fileElements:
        rootElement.append(stripNS(curFile, xmlns))

    return xml.etree.ElementTree.tostring(ek.ss(rootElement))


def saveNZB(nzbName, nzbString):
    try:
        with ek.ek(open, nzbName + ".nzb", 'w') as nzb_fh:
            nzb_fh.write(nzbString)

    except EnvironmentError, e:
        logger.log(u"Unable to save NZB: " + ex(e), logger.ERROR)


def stripNS(element, ns):
    element.tag = element.tag.replace("{" + ns + "}", "")
    for curChild in element.getchildren():
        stripNS(curChild, ns)

    return element


def splitResult(result):
    urlData = helpers.getURL(result.url, session=requests.Session())
    if urlData is None:
        logger.log(u"Unable to load url " + result.url + ", can't download season NZB", logger.ERROR)
        return False

    # parse the season ep name
    try:
        np = NameParser(False, showObj=result.show)
        parse_result = np.parse(result.name)
    except InvalidNameException:
        logger.log(u"Unable to parse the filename " + result.name + " into a valid episode", logger.DEBUG)
        return False
    except InvalidShowException:
        logger.log(u"Unable to parse the filename " + result.name + " into a valid show", logger.DEBUG)
        return False

    # bust it up
    season = parse_result.season_number if parse_result.season_number != None else 1

    separateNZBs, xmlns = getSeasonNZBs(result.name, urlData, season)

    resultList = []

    for newNZB in separateNZBs:

        logger.log(u"Split out " + newNZB + " from " + result.name, logger.DEBUG)

        # parse the name
        try:
            np = NameParser(False, showObj=result.show)
            parse_result = np.parse(newNZB)
        except InvalidNameException:
            logger.log(u"Unable to parse the filename " + newNZB + " into a valid episode", logger.DEBUG)
            return False
        except InvalidShowException:
            logger.log(u"Unable to parse the filename " + newNZB + " into a valid show", logger.DEBUG)
            return False

        # make sure the result is sane
        if (parse_result.season_number != None and parse_result.season_number != season) or (
                parse_result.season_number == None and season != 1):
            logger.log(
                u"Found " + newNZB + " inside " + result.name + " but it doesn't seem to belong to the same season, ignoring it",
                logger.WARNING)
            continue
        elif len(parse_result.episode_numbers) == 0:
            logger.log(
                u"Found " + newNZB + " inside " + result.name + " but it doesn't seem to be a valid episode NZB, ignoring it",
                logger.WARNING)
            continue

        wantEp = True
        for epNo in parse_result.episode_numbers:
            if not result.extraInfo[0].wantEpisode(season, epNo, result.quality):
                logger.log(u"Ignoring result " + newNZB + " because we don't want an episode that is " +
                           Quality.qualityStrings[result.quality], logger.INFO)
                wantEp = False
                break
        if not wantEp:
            continue

        # get all the associated episode objects
        epObjList = []
        for curEp in parse_result.episode_numbers:
            epObjList.append(result.extraInfo[0].getEpisode(season, curEp))

        # make a result
        curResult = classes.NZBDataSearchResult(epObjList)
        curResult.name = newNZB
        curResult.provider = result.provider
        curResult.quality = result.quality
        curResult.extraInfo = [createNZBString(separateNZBs[newNZB], xmlns)]

        resultList.append(curResult)

    return resultList
