# Copyright (C) 2009 Canonical
#
# Authors:
#  Michael Vogt
#
# This program 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; version 3.
#
# This program 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
# this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

from gi.repository import GObject
import gettext
import glob
import locale
import logging
import os
import string
import xapian

# we use lxml.etree instead of xml.etree.ElementTree because it's quite a bit
# faster, especially on slow machines like ARM
import lxml.etree as ET

from xml.sax.saxutils import escape as xml_escape
from xml.sax.saxutils import unescape as xml_unescape

import softwarecenter.paths

from softwarecenter.enums import (
    AppInfoFields,
    NonAppVisibility,
    SortMethods,
)
from softwarecenter.backend.recagent import RecommenderAgent
from softwarecenter.db.appfilter import AppFilter
from softwarecenter.db.enquire import AppEnquire
from softwarecenter.region import get_region_cached
from softwarecenter.utils import utf8

from gettext import gettext as _

# not possible not use local logger
LOG = logging.getLogger(__name__)


def get_category_by_name(categories, untrans_name):
    # find a specific category
    cat = [cat for cat in categories if cat.untranslated_name == untrans_name]
    if cat:
        return cat[0]
    return None


def categories_sorted_by_name(categories):
    # sort categories by name
    sorted_catnames = []
    # first pass, sort by translated names
    for cat in categories:
        sorted_catnames.append(cat.name)
    sorted_catnames = sorted(sorted_catnames, cmp=locale.strcoll)

    # second pass, assemble cats by sorted their sorted catnames
    sorted_cats = []
    for name in sorted_catnames:
        for cat in categories:
            if cat.name == name:
                sorted_cats.append(cat)
                break
    return sorted_cats


def get_query_for_category(db, untranslated_category_name):
    cat_parser = CategoriesParser(db)
    categories = cat_parser.parse_applications_menu()
    for c in categories:
        if untranslated_category_name == c.untranslated_name:
            query = c.query
            return query
    return False


class Category(GObject.GObject):
    """represents a menu category"""

    def __init__(self, untranslated_name, name, iconname, query,
                 only_unallocated=True, dont_display=False, flags=[],
                 subcategories=[], sortmode=SortMethods.BY_ALPHABET,
                 item_limit=0):
        GObject.GObject.__init__(self)
        if type(name) == str:
            self.name = unicode(name, 'utf8').encode('utf8')
        else:
            self.name = name.encode('utf8')
        self.untranslated_name = untranslated_name
        self.iconname = iconname
        for subcategory in subcategories:
            query = xapian.Query(xapian.Query.OP_OR, query, subcategory.query)
        self.query = query
        self.only_unallocated = only_unallocated
        self.subcategories = subcategories
        self.dont_display = dont_display
        self.flags = flags
        self.sortmode = sortmode
        self.item_limit = item_limit

    @property
    def is_forced_sort_mode(self):
        return (self.sortmode != SortMethods.BY_ALPHABET)

    def get_documents(self, db):
        """ return the database docids for the given category """
        enq = AppEnquire(db._aptcache, db)
        app_filter = AppFilter(db, db._aptcache)
        if "available-only" in self.flags:
            app_filter.set_available_only(True)
        if "not-installed-only" in self.flags:
            app_filter.set_not_installed_only(True)
        enq.set_query(self.query,
                      limit=self.item_limit,
                      filter=app_filter,
                      sortmode=self.sortmode,
                      nonapps_visible=NonAppVisibility.ALWAYS_VISIBLE,
                      nonblocking_load=False)
        return enq.get_documents()

    def __str__(self):
        return "<Category: name='%s', sortmode='%s', "\
               "item_limit='%s'>" % (
                   self.name, self.sortmode, self.item_limit)


class RecommendedForYouCategory(Category):

    __gsignals__ = {
        "needs-refresh": (GObject.SIGNAL_RUN_LAST,
                          GObject.TYPE_NONE,
                          (),
                          ),
        "recommender-agent-error": (GObject.SIGNAL_RUN_LAST,
                                    GObject.TYPE_NONE,
                                    (GObject.TYPE_STRING,),
                                    ),
    }

    def __init__(self, db, subcategory=None):
        self.db = db
        self.subcategory = subcategory
        if subcategory:
            # this is the set of recommendations for a given subcategory
            cat_title = u"Recommended For You in %s" % (
                subcategory.untranslated_name)
            tr_title = utf8(_("Recommended For You in %s")) % utf8(
                subcategory.name)
        else:
            # this is the full set of recommendations for e.g. the lobby view
            cat_title = u"Recommended For You"
            tr_title = _("Recommended For You")
        super(RecommendedForYouCategory, self).__init__(
                cat_title,
                tr_title,
                None,
                xapian.Query(),
                flags=['available-only', 'not-installed-only'],
                item_limit=60)
        self.recommender_agent = RecommenderAgent()
        self.recommender_agent.connect(
            "recommend-me", self._recommend_me_result)
        self.recommender_agent.connect(
            "error", self._recommender_agent_error)
        self.recommender_agent.query_recommend_me()

    def _recommend_me_result(self, recommender_agent, result_list):
        pkgs = []
        for item in result_list['data']:
            pkgs.append(item['package_name'])
        if self.subcategory:
            self.query = xapian.Query(xapian.Query.OP_AND,
                                  self.db.get_query_for_pkgnames(pkgs),
                                  self.subcategory.query)
        else:
            self.query = self.db.get_query_for_pkgnames(pkgs)
        self.emit("needs-refresh")

    def _recommender_agent_error(self, recommender_agent, msg):
        LOG.warn("Error while accessing the recommender service: %s"
                                                            % msg)
        self.emit("recommender-agent-error", msg)


class AppRecommendationsCategory(Category):

    __gsignals__ = {
        "needs-refresh": (GObject.SIGNAL_RUN_LAST,
                          GObject.TYPE_NONE,
                          (),
                          ),
        "recommender-agent-error": (GObject.SIGNAL_RUN_LAST,
                                    GObject.TYPE_NONE,
                                    (GObject.TYPE_STRING,),
                                    ),
    }

    def __init__(self, db, pkgname):
        super(AppRecommendationsCategory, self).__init__(
            u"People Also Installed",
            _(u"People Also Installed"),
            None,
            xapian.Query(),
            flags=['available-only', 'not-installed-only'],
            item_limit=4)
        self.db = db
        self.recommender_agent = RecommenderAgent()
        self.recommender_agent.connect(
            "recommend-app", self._recommend_app_result)
        self.recommender_agent.connect(
            "error", self._recommender_agent_error)
        self.recommender_agent.query_recommend_app(pkgname)

    def _recommend_app_result(self, recommender_agent, result_list):
        pkgs = []
        for item in result_list['data']:
            pkgs.append(item['package_name'])
        self.query = self.db.get_query_for_pkgnames(pkgs)
        self.emit("needs-refresh")

    def _recommender_agent_error(self, recommender_agent, msg):
        LOG.warn("Error while accessing the recommender service: %s"
                                                            % msg)
        self.emit("recommender-agent-error", msg)


class CategoriesParser(object):
    """
    Parser that is able to read the categories from a menu file
    """

    # class wide cache to avoid multiple parsing
    CATEGORIES_PARSER_CACHE = {}

    def __init__(self, db):
        self.db = db
        # build the string substitution support
        self._build_string_template_dict()

    def parse_applications_menu(self, datadir=None, use_cache=True):
        """ parse a application menu and return a list of Category objects """

        if datadir is None:
            datadir = softwarecenter.paths.desktopdir

        # the DB must be part of the cache key because different DBs may
        # yield different results (e.g. in the tests)
        cachekey = (self.db, datadir)
        if use_cache and cachekey in self.CATEGORIES_PARSER_CACHE:
            return self.CATEGORIES_PARSER_CACHE[cachekey]

        categories = []
        # we support multiple menu files and menu drop ins
        menu_files = [datadir + "/desktop/software-center.menu"]
        menu_files += glob.glob(datadir + "/menu.d/*.menu")
        for f in menu_files:
            if not os.path.exists(f):
                continue
            tree = ET.parse(f)
            root = tree.getroot()
            for child in root.getchildren():
                category = None
                if child.tag == "Menu":
                    category = self._parse_menu_tag(child)
                if category:
                    categories.append(category)
        # post processing for <OnlyUnallocated>
        # now build the unallocated queries, once for top-level,
        # and for the subcategories. this means that subcategories
        # can have a "OnlyUnallocated/" that applies only to
        # unallocated entries in their sublevel
        for cat in categories:
            self._build_unallocated_queries(cat.subcategories)
        self._build_unallocated_queries(categories)

        # add to the cache
        self.CATEGORIES_PARSER_CACHE[cachekey] = categories

        # debug print
        for cat in categories:
            LOG.debug("%s %s %s" % (cat.name.decode('utf8'),
                                    cat.iconname,
                                    cat.query))
        return categories

    def _build_string_template_dict(self):
        """ this build the dict used to substitute menu entries dynamically,
            currently used for the CURRENT_REGION
        """
        region = "%s" % get_region_cached()["countrycode"]
        self._template_dict = {'CURRENT_REGION': region}

    def _substitute_string_if_needed(self, t):
        """ substitute the given string with the current supported dynamic
            menu keys
        """
        return string.Template(t).substitute(self._template_dict)

    def _cat_sort_cmp(self, a, b):
        """sort helper for the categories sorting"""
        #print "cmp: ", a.name, b.name
        if a.untranslated_name == "System":
            return 1
        elif b.untranslated_name == "System":
            return -1
        elif a.untranslated_name == "Developer Tools":
            return 1
        elif b.untranslated_name == "Developer Tools":
            return -1
        return locale.strcoll(a.name, b.name)

    def _parse_directory_tag(self, element):
        from softwarecenter.db.update import DesktopConfigParser
        cp = DesktopConfigParser()
        fname = "/usr/share/desktop-directories/%s" % element.text
        if not os.path.exists(fname):
            return None
        LOG.debug("reading '%s'" % fname)
        cp.read(fname)
        try:
            untranslated_name = name = cp.get("Desktop Entry", "Name")
        except Exception:
            LOG.warn("'%s' has no name" % fname)
            return None
        try:
            gettext_domain = cp.get("Desktop Entry", "X-Ubuntu-Gettext-Domain")
        except:
            gettext_domain = None
        try:
            icon = cp.get("Desktop Entry", "Icon")
        except Exception:
            icon = "applications-other"
        name = cp.get_value(AppInfoFields.NAME, translated=True)
        return (untranslated_name, name, gettext_domain, icon)

    def _parse_flags_tag(self, element):
        flags = []
        for an_elem in element.getchildren():
            flags.append(an_elem.text)
        return flags

    def _parse_and_or_not_tag(self, element, query, xapian_op):
        """parse a <And>, <Or>, <Not> tag """
        for operator_elem in element.getchildren():
            # get the query-text
            if operator_elem.text:
                qtext = self._substitute_string_if_needed(
                    operator_elem.text).lower()
            # parse the individual element
            if operator_elem.tag == "Not":
                query = self._parse_and_or_not_tag(
                    operator_elem, query, xapian.Query.OP_AND_NOT)
            elif operator_elem.tag == "Or":
                or_elem = self._parse_and_or_not_tag(
                    operator_elem, xapian.Query(), xapian.Query.OP_OR)
                query = xapian.Query(xapian.Query.OP_AND, or_elem, query)
            elif operator_elem.tag == "Category":
                LOG.debug("adding: %s" % operator_elem.text)
                q = xapian.Query("AC" + qtext)
                query = xapian.Query(xapian_op, query, q)
            elif operator_elem.tag == "SCSection":
                LOG.debug("adding section: %s" % operator_elem.text)
                # we have the section once in apt-xapian-index and once
                # in our own DB this is why we need two prefixes
                # FIXME: ponder if it makes sense to simply write
                #        out XS in update-software-center instead of AE?
                q = xapian.Query(xapian.Query.OP_OR,
                                 xapian.Query("XS" + qtext),
                                 xapian.Query("AE" + qtext))
                query = xapian.Query(xapian_op, query, q)
            elif operator_elem.tag == "SCType":
                LOG.debug("adding type: %s" % operator_elem.text)
                q = xapian.Query("AT" + qtext)
                query = xapian.Query(xapian_op, query, q)
            elif operator_elem.tag == "SCDebtag":
                LOG.debug("adding debtag: %s" % operator_elem.text)
                q = xapian.Query("XT" + qtext)
                query = xapian.Query(xapian_op, query, q)
            elif operator_elem.tag == "SCChannel":
                LOG.debug("adding channel: %s" % operator_elem.text)
                q = xapian.Query("AH" + qtext)
                query = xapian.Query(xapian_op, query, q)
            elif operator_elem.tag == "SCOrigin":
                LOG.debug("adding origin: %s" % operator_elem.text)
                # FIXME: origin is currently case-sensitive?!?
                q = xapian.Query("XOO" + operator_elem.text)
                query = xapian.Query(xapian_op, query, q)
            elif operator_elem.tag == "SCPkgname":
                LOG.debug("adding tag: %s" % operator_elem.text)
                # query both axi and s-c
                q1 = xapian.Query("AP" + qtext)
                q = xapian.Query(xapian.Query.OP_OR, q1,
                                 xapian.Query("XP" + qtext))
                query = xapian.Query(xapian_op, query, q)
            elif operator_elem.tag == "SCPkgnameWildcard":
                LOG.debug("adding tag: %s" % operator_elem.text)
                # query both axi and s-c and ensure that the pkgname is
                # mangled to workaround xapian's query parser lack of
                # quoting :/
                s = "pkg_wildcard:%s" % qtext.replace("-", "_")
                q = self.db.xapian_parser.parse_query(s,
                    xapian.QueryParser.FLAG_WILDCARD)
                query = xapian.Query(xapian_op, query, q)
            else:
                LOG.warn("UNHANDLED: %s %s" % (operator_elem.tag,
                    operator_elem.text))
        return query

    def _parse_include_tag(self, element):
        for include in element.getchildren():
            if include.tag == "Or":
                query = xapian.Query()
                return self._parse_and_or_not_tag(include, query,
                    xapian.Query.OP_OR)
            if include.tag == "And":
                query = xapian.Query("")
                return self._parse_and_or_not_tag(include, query,
                    xapian.Query.OP_AND)
            # without "and" tag we take the first entry
            elif include.tag == "Category":
                return xapian.Query("AC" + include.text.lower())
            else:
                LOG.warn("UNHANDLED: _parse_include_tag: %s" % include.tag)
        # empty query matches all
        return xapian.Query("")

    def _parse_menu_tag(self, item):
        name = None
        untranslated_name = None
        query = None
        icon = None
        only_unallocated = False
        dont_display = False
        flags = []
        subcategories = []
        sortmode = SortMethods.BY_ALPHABET
        item_limit = 0
        for element in item.getchildren():
            # ignore inline translations, we use gettext for this
            if (element.tag == "Name" and
                    '{http://www.w3.org/XML/1998/namespace}lang' in
                    element.attrib):
                continue
            if element.tag == "Name":
                untranslated_name = element.text
                # gettext/xml writes stuff from software-center.menu
                # out into the pot as escaped xml, so we need to escape
                # the name first, get the translation and unescape it again
                escaped_name = xml_escape(untranslated_name)
                name = xml_unescape(gettext.gettext(escaped_name))
            elif element.tag == "SCIcon":
                icon = element.text
            elif element.tag == 'Flags':
                flags = self._parse_flags_tag(element)
            elif element.tag == "Directory":
                l = self._parse_directory_tag(element)
                if l:
                    (untranslated_name, name, gettext_domain, icon) = l
            elif element.tag == "Include":
                query = self._parse_include_tag(element)
            elif element.tag == "OnlyUnallocated":
                only_unallocated = True
            elif element.tag == "SCDontDisplay":
                dont_display = True
            elif element.tag == "SCSortMode":
                sortmode = int(element.text)
                if not self._verify_supported_sort_mode(sortmode):
                    return None
            elif element.tag == "SCItemLimit":
                item_limit = int(element.text)
            elif element.tag == "Menu":
                subcat = self._parse_menu_tag(element)
                if subcat:
                    subcategories.append(subcat)
            else:
                LOG.warn("UNHANDLED tag in _parse_menu_tag: %s" % element.tag)

        if untranslated_name and query:
            return Category(untranslated_name, name, icon, query,
                only_unallocated, dont_display, flags, subcategories,
                sortmode, item_limit)
        else:
            LOG.warn("UNHANDLED entry: %s %s %s %s" % (name,
                                                       untranslated_name,
                                                       icon,
                                                       query))
        return None

    def _verify_supported_sort_mode(self, sortmode):
        """ verify that we use a sortmode that we know and can handle """
        # always supported
        if sortmode in (SortMethods.UNSORTED,
                        SortMethods.BY_ALPHABET,
                        SortMethods.BY_TOP_RATED,
                        SortMethods.BY_SEARCH_RANKING,
                        SortMethods.BY_CATALOGED_TIME):
            return True
        # we don't know this sortmode
        LOG.error("unknown sort mode '%i'" % sortmode)
        return False

    def _build_unallocated_queries(self, categories):
        for cat_unalloc in categories:
            if not cat_unalloc.only_unallocated:
                continue
            for cat in categories:
                if cat.name != cat_unalloc.name:
                    cat_unalloc.query = xapian.Query(xapian.Query.OP_AND_NOT,
                        cat_unalloc.query, cat.query)
            #print cat_unalloc.name, cat_unalloc.query
        return


# static category mapping for the tiles

category_cat = {
    'Utility': 'Accessories',
    'System': 'Accessories',
    'Education': 'Education',
    'Game': 'Games',
    'Sports': 'Games',
    'Graphics': 'Graphics',
    'Network': 'Internet',
    'Office': 'Office',
    'Science': 'Science & Engineering',
    'Audio': 'Sound & Video',
    'AudioVideo': 'Sound & Video',
    'Video': 'Sound & Video',
    'Settings': 'Themes & Tweaks',
    'Accessibility': 'Universal Access',
    'Development': 'Developer Tools',
    'X-Publishing': 'Books & Magazines',
}

category_subcat = {
    'BoardGame': 'Games;Board Games',
    'CardGame': 'Games;Card Games',
    'LogicGame': 'Games;Puzzles',
    'RolePlaying': 'Games;Role Playing',
    'SportsGame': 'Games;Sports',
    '3DGraphics': 'Graphics;3D Graphics',
    'VectorGraphics': 'Graphics;Drawing',
    'RasterGraphics': 'Graphics;Painting & Editing',
    'Photography': 'Graphics;Photography',
    'Publishing': 'Graphics;Publishing',
    'Scanning': 'Graphics;Scanning & OCR',
    'OCR': 'Graphics;Scanning & OCR',
    'Viewer': 'Graphics;Viewers',
    'InstantMessaging': 'Internet;Chat',
    'IRCClient': 'Internet;Chat',
    'FileTransfer': 'Internet;File Sharing',
    'Email': 'Internet;Mail',
    'WebBrowser': 'Internet;Web Browsers',
    'Astronomy': 'Science & Engineering;Astronomy',
    'Biology': 'Science & Engineering;Biology',
    'Chemistry': 'Science & Engineering;Chemistry',
    'ArtificialIntelligence': 'Science & Engineering;Computing & Robotics',
    'ComputerScience': 'Science & Engineering;Computing & Robotics',
    'Robotics': 'Science & Engineering;Computing & Robotics',
    'Electronics': 'Science & Engineering;Electronics',
    'Engineering': 'Science & Engineering;Engineering',
    'Geography': 'Science & Engineering;Geography',
    'Geology': 'Science & Engineering;Geology',
    'Geoscience': 'Science & Engineering;Geology',
    'DataVisualization': 'Science & Engineering;Mathematics',
    'Math': 'Science & Engineering;Mathematics',
    'NumericalAnalysis': 'Science & Engineering;Mathematics',
    'MedicalSoftware': 'Science & Engineering;Medicine',
    'Electricity': 'Science & Engineering;Physics',
    'Physics': 'Science & Engineering;Physics',
    'Debugger': 'Developer Tools;Debugging',
    'GUIDesigner': 'Developer Tools;Graphic Interface Design',
    'IDE': 'Developer Tools;IDEs',
    'Translation': 'Developer Tools;Localization',
    'Profiling': 'Developer Tools;Profiling',
    'RevisionControl': 'Developer Tools;Version Control',
    'WebDevelopment': 'Developer Tools;Web Development',
}