from django.conf import settings

from django.core import urlresolvers

from django.core.exceptions import ImproperlyConfigured

# Attributes required in the top-level app for COMMENTS_APP

REQUIRED_COMMENTS_APP_ATTRIBUTES = ["get_model", "get_form", "get_form_target"]

def get_comment_app():

    """

    Get the comment app (i.e. "django.contrib.comments") as defined in the settings

    """

    # Make sure the app's in INSTALLED_APPS

    comments_app = get_comment_app_name()

    if comments_app not in settings.INSTALLED_APPS:

        raise ImproperlyConfigured("The COMMENTS_APP (%r) "\

                                   "must be in INSTALLED_APPS" % settings.COMMENTS_APP)

    # Try to import the package

    try:

        package = __import__(comments_app, '', '', [''])

    except ImportError:

        raise ImproperlyConfigured("The COMMENTS_APP setting refers to "\

                                   "a non-existing package.")

    # Make sure some specific attributes exist inside that package.

    for attribute in REQUIRED_COMMENTS_APP_ATTRIBUTES:

        if not hasattr(package, attribute):

            raise ImproperlyConfigured("The COMMENTS_APP package %r does not "\

                                       "define the (required) %r function" % \

                                            (package, attribute))

    return package

def get_comment_app_name():

    """

    Returns the name of the comment app (either the setting value, if it

    exists, or the default).

    """

    return getattr(settings, 'COMMENTS_APP', 'django.contrib.comments')

def get_model():

    from django.contrib.comments.models import Comment

    return Comment

def get_form():

    from django.contrib.comments.forms import CommentForm

    return CommentForm

def get_form_target():

    return urlresolvers.reverse("django.contrib.comments.views.comments.post_comment")

def get_flag_url(comment):

    """

    Get the URL for the "flag this comment" view.

    """

    if get_comment_app_name() != __name__ and hasattr(get_comment_app(), "get_flag_url"):

        return get_comment_app().get_flag_url(comment)

    else:

        return urlresolvers.reverse("django.contrib.comments.views.moderation.flag", args=(comment.id,))

def get_delete_url(comment):

    """

    Get the URL for the "delete this comment" view.

    """

    if get_comment_app_name() != __name__ and hasattr(get_comment_app(), "get_delete_url"):

        return get_comment_app().get_flag_url(get_delete_url)

    else:

        return urlresolvers.reverse("django.contrib.comments.views.moderation.delete", args=(comment.id,))

def get_approve_url(comment):

    """

    Get the URL for the "approve this comment from moderation" view.

    """

    if get_comment_app_name() != __name__ and hasattr(get_comment_app(), "get_approve_url"):

        return get_comment_app().get_approve_url(comment)

    else:

        return urlresolvers.reverse("django.contrib.comments.views.moderation.approve", args=(comment.id,))