# badlinks.py - plugin to list bad links
#
# Copyright (C) 1998, 1999 Albert Hopkins (marduk)
# Copyright (C) 2002 Mike W. Meyer
# Copyright (C) 2005, 2006, 2007, 2011, 2013 Arthur de Jong
#
# 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 St, Fifth Floor, Boston, MA  02110-1301 USA
#
# The files produced as output from the software do not automatically fall
# under the copyright of the software, unless explicitly stated otherwise.

"""Present a listing of links that point to non-existent pages."""

__title__ = 'bad links'
__author__ = 'Arthur de Jong'
__outputfile__ = 'badlinks.html'

from sqlalchemy.orm import joinedload

from webcheck.db import Session, Link
from webcheck.output import render


def postprocess(crawler):
    """Add all bad links as pageproblems on pages where they are linked."""
    session = Session()
    # find all links with link problems
    links = session.query(Link).filter(Link.linkproblems.any()).options(joinedload(Link.linkproblems))
    # TODO: probably make it a nicer query over all linkproblems
    for link in links:
        # add a reference to the problem map
        for problem in link.linkproblems:
            for parent in link.parents:
                parent.add_pageproblem('bad link: %s: %s' % (link.url, problem))
    session.commit()
    session.close()


def generate(crawler):
    """Present the list of bad links."""
    session = Session()
    links = session.query(Link).filter(Link.linkproblems.any())
    links = links.order_by(Link.url).options(joinedload(Link.linkproblems))
    render(__outputfile__, crawler=crawler, title=__title__,
           links=links)
    session.close()