#
# Gramps - a GTK+/GNOME based genealogy program
#
# Copyright (C) 2002-2006  Donald N. Allingham
#
# 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; either version 2 of the License, or
# (at your option) any later version.
#
# 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.
#

#-------------------------------------------------------------------------
#
# Standard Python modules
#
#-------------------------------------------------------------------------
from ....const import GRAMPS_LOCALE as glocale
_ = glocale.translation.gettext

#-------------------------------------------------------------------------
#
# Gramps modules
#
#-------------------------------------------------------------------------
from .. import Rule

#-------------------------------------------------------------------------
#
# IsLessThanNthGenerationAncestorOf
#
#-------------------------------------------------------------------------
class IsLessThanNthGenerationAncestorOf(Rule):
    """Rule that checks for a person that is an ancestor of a specified person
    not more than N generations away"""

    labels = [ _('ID:'), _('Number of generations:') ]
    name = _('Ancestors of <person> not more than <N> generations away')
    category = _("Ancestral filters")
    description = _("Matches people that are ancestors "
                    "of a specified person not more than N generations away")

    def prepare(self, db, user):
        self.db = db
        self.map = set()
        person = db.get_person_from_gramps_id(self.list[0])
        if person:
            root_handle = person.get_handle()
            if root_handle:
                self.init_ancestor_list(root_handle)

    def init_ancestor_list(self, root_handle):
        queue = [(root_handle, 1)] # generation 1 is root
        while queue:
            handle, gen = queue.pop(0) # pop off front of queue
            if handle in self.map:
                # if we have been here before, skip
                continue
            self.map.add(handle)
            gen += 1
            if gen <= int(self.list[1]):
                p = self.db.get_person_from_handle(handle)
                fam_id = p.get_main_parents_family_handle()
                if fam_id:
                    fam = self.db.get_family_from_handle(fam_id)
                    if fam:
                        f_id = fam.get_father_handle()
                        m_id = fam.get_mother_handle()
                        # append to back of queue:
                        if f_id:
                            queue.append((f_id, gen))
                        if m_id:
                            queue.append((m_id, gen))

    def reset(self):
        self.map.clear()

    def apply(self,db,person):
        return person.handle in self.map
