from django.core import urlresolvers

from django.contrib.sitemaps import Sitemap

class GeoRSSSitemap(Sitemap):

    """

    A minimal hook to produce sitemaps for GeoRSS feeds.

    """

    def __init__(self, feed_dict, slug_dict=None):

        """

        This sitemap object initializes on a feed dictionary (as would be passed

        to `django.contrib.syndication.views.feed`) and a slug dictionary.  

        If the slug dictionary is not defined, then it's assumed the keys provide

        the URL parameter to the feed.  However, if you have a complex feed (e.g.,

        you override `get_object`, then you'll need to provide a slug dictionary.

        The slug dictionary should have the same keys as the feed dictionary, but 

        each value in the slug dictionary should be a sequence of slugs that may 

        be used for valid feeds.  For example, let's say we have a feed that 

        returns objects for a specific ZIP code in our feed dictionary:

            feed_dict = {'zipcode' : ZipFeed}

        Then we would use a slug dictionary with a list of the zip code slugs

        corresponding to feeds you want listed in the sitemap:

            slug_dict = {'zipcode' : ['77002', '77054']}

        """

        # Setting up.

        self.feed_dict = feed_dict

        self.locations = []

        if slug_dict is None: slug_dict = {}

        # Getting the feed locations.

        for section in feed_dict.keys():

            if slug_dict.get(section, False):

                for slug in slug_dict[section]:

                    self.locations.append('%s/%s' % (section, slug))

            else:

                self.locations.append(section)

    def get_urls(self, page=1):

        """

        This method is overrridden so the appropriate `geo_format` attribute

        is placed on each URL element.

        """

        urls = Sitemap.get_urls(self, page=page)

        for url in urls: url['geo_format'] = 'georss'

        return urls

    def items(self):

        return self.locations

    def location(self, obj):

        return urlresolvers.reverse('django.contrib.syndication.views.feed', args=(obj,))