""" Django notifications template tags file """

# -*- coding: utf-8 -*-
from distutils.version import (  # pylint: disable=no-name-in-module,import-error
    StrictVersion,
)

from django import get_version
from django.template import Library
from django.utils.html import format_html

try:
    from django.urls import reverse
except ImportError:
    from django.core.urlresolvers import (  # pylint: disable=no-name-in-module,import-error
        reverse,
    )

register = Library()


def notifications_unread(context):
    user = user_context(context)
    if not user:
        return ""
    return user.notifications.unread().count()


if StrictVersion(get_version()) >= StrictVersion("2.0"):
    notifications_unread = register.simple_tag(takes_context=True)(
        notifications_unread
    )  # pylint: disable=invalid-name
else:
    notifications_unread = register.assignment_tag(takes_context=True)(
        notifications_unread
    )  # noqa


@register.filter
def has_notification(user):
    if user:
        return user.notifications.unread().exists()
    return False


# Requires vanilla-js framework - http://vanilla-js.com/
@register.simple_tag
def register_notify_callbacks(
    badge_class="live_notify_badge",  # pylint: disable=too-many-arguments,missing-docstring
    menu_class="live_notify_list",
    refresh_period=15,
    callbacks="",
    api_name="list",
    fetch=5,
):
    refresh_period = int(refresh_period) * 1000

    if api_name == "list":
        api_url = reverse("notifications:live_unread_notification_list")
    elif api_name == "count":
        api_url = reverse("notifications:live_unread_notification_count")
    else:
        return ""
    definitions = """
        notify_badge_class='{badge_class}';
        notify_menu_class='{menu_class}';
        notify_api_url='{api_url}';
        notify_fetch_count='{fetch_count}';
        notify_unread_url='{unread_url}';
        notify_mark_all_unread_url='{mark_all_unread_url}';
        notify_refresh_period={refresh};
    """.format(
        badge_class=badge_class,
        menu_class=menu_class,
        refresh=refresh_period,
        api_url=api_url,
        unread_url=reverse("notifications:unread"),
        mark_all_unread_url=reverse("notifications:mark_all_as_read"),
        fetch_count=fetch,
    )

    script = "<script>" + definitions
    for callback in callbacks.split(","):
        script += "register_notifier(" + callback + ");"
    script += "</script>"
    return format_html(script)


@register.simple_tag(takes_context=True)
def live_notify_badge(context, badge_class="live_notify_badge"):
    user = user_context(context)
    if not user:
        return ""

    html = "<span class='{badge_class}'>{unread}</span>".format(
        badge_class=badge_class, unread=user.notifications.unread().count()
    )
    return format_html(html)


@register.simple_tag
def live_notify_list(list_class="live_notify_list"):
    html = "<ul class='{list_class}'></ul>".format(list_class=list_class)
    return format_html(html)


def user_context(context):
    if "user" not in context:
        return None

    request = context["request"]
    user = request.user
    try:
        user_is_anonymous = user.is_anonymous()
    except TypeError:  # Django >= 1.11
        user_is_anonymous = user.is_anonymous

    if user_is_anonymous:
        return None
    return user