from django import template
from django.core import urlresolvers

register = template.Library()

@register.inclusion_tag('conntrackt/link.html')
def html_link(view, title, identifier = None, html_class = None):
    '''
    A small wrapper for showing HTML links.

    Arguments:

    view - View name for which the URL should be shown.

    title - Title which will be shown as the link.

    identifier - Identifier which is passed to the view for processing.

    html_class - Class which should be assigned to the link.
    '''

    return {'view': view, 'identifier': identifier, 'title': title, 'html_class': html_class}

@register.simple_tag(takes_context = True)
def active_link(context, url_name, return_value='active', **kwargs):
    matches = current_url_equals(context, url_name, **kwargs)
    return return_value if matches else ''
 
 
def current_url_equals(context, url_name, **kwargs):
    resolved = False
    try:
        resolved = urlresolvers.resolve(context.get('request').path)
    except:
        pass
    matches = resolved and resolved.url_name == url_name
    if matches and kwargs:
        for key in kwargs:
            kwarg = kwargs.get(key)
            resolved_kwarg = resolved.kwargs.get(key)
            if not resolved_kwarg or kwarg != resolved_kwarg:
                return False
    return matches