# -*- coding: utf-8 -*-

"""
    PyLucid back links Plugin
    ~~~~~~~~~~~~~~~~~~~~~~~~~

    Generates a horizontal backlink bar.
    Adjastuble with the following Parameters

    - print_last_page = False (default)
        if print_last_page has the value True, then the actual page will be the
        last page in the bar. Otherwise the parentpage.

    - print_index = False (default)
        display a link to the index ("/") if = True


    - index = "Index" (default)
        the name that is printed for the indexpage


    Last commit info:
    ~~~~~~~~~
    $LastChangedDate$
    $Rev$
    $Author$

    :created: 29.11.2005 10:14:02 by Jens Diemer
    :copyleft: 2005-2008 by the PyLucid team, see AUTHORS for more details.
    :license: GNU GPL v2 or above, see LICENSE for more details
"""

__version__= "$Rev$"


from django.utils.safestring import mark_safe

from PyLucid.system.BasePlugin import PyLucidBasePlugin
from PyLucid.models import Page, Plugin

class back_links(PyLucidBasePlugin):

    def lucidTag(self, **kwargs):
        """
        generate the backlinks
        TODO: **kwargs only for Backwards-incompatible changes info
        """
        if self.request.debug == True and kwargs != {}:
            self.page_msg(
                "DeprecationWarning:"
                " kwargs in back_links plugin are obsolete. Please remove them."
            )
            return

        # Get the preferences from the database:
        preferences = self.get_preferences()
        if preferences == None:
            # preferences not in database -> reinit required
            if self.request.debug == True:
                msg = (
                    '<a href="http://www.pylucid.org/_goto/121/changes/#23-05-2008-back_links">'
                    'reinit "back_links" plugin required!</a>'
                )
                self.page_msg.red(mark_safe(msg))
                return

        current_page = self.context["PAGE"]
        if preferences["print_last_page"] == True:
            print_page = current_page
        else:
            print_page = current_page.parent
            if not print_page:
                # There exist no higher-ranking page
                return ""

        data = self._backlink_data(print_page)
        data.reverse()

        context = {
            "pages": data,
            "preferences": preferences,
        }
        self._render_template("back_links", context)#, debug=True)

    def _backlink_data(self, parent_page):
        """
        make a list of all pages in the current way back to the index page.
        """
        data = []
        while parent_page:
            page_id = parent_page.id
            page = Page.objects.get(id=page_id)
            parent_page = page.parent

            data.append(page)

        return data