from django.core.paginator import EmptyPage
from django.http import Http404
from django.shortcuts import render
from django.urls import reverse
from django.utils.decorators import method_decorator
from django.views.decorators.csrf import csrf_protect

from boards import settings
from boards.abstracts.constants import PARAM_PAGE
from boards.abstracts.paginator import get_paginator
from boards.abstracts.settingsmanager import get_settings_manager, \
    SETTING_ONLY_FAVORITES
from boards.forms import ThreadForm, PlainErrorList
from boards.models import Post, Thread
from boards.settings import SECTION_VIEW
from boards.views.base import BaseBoardView, CONTEXT_FORM
from boards.views.mixins import PaginatedMixin, \
    DispatcherMixin, PARAMETER_METHOD

ORDER_BUMP = 'bump'

PARAM_ORDER = 'order'

FORM_TAGS = 'tags'
FORM_TEXT = 'text'
FORM_TITLE = 'title'
FORM_IMAGE = 'image'
FORM_THREADS = 'threads'

TAG_DELIMITER = ' '

PARAMETER_CURRENT_PAGE = 'current_page'
PARAMETER_PAGINATOR = 'paginator'
PARAMETER_THREADS = 'threads'
PARAMETER_ADDITIONAL = 'additional_params'
PARAMETER_RSS_URL = 'rss_url'

TEMPLATE = 'boards/all_threads.html'
DEFAULT_PAGE = 1


class AllThreadsView(BaseBoardView, PaginatedMixin, DispatcherMixin):

    tag_name = ''

    def __init__(self):
        self.settings_manager = None
        super(AllThreadsView, self).__init__()

    @method_decorator(csrf_protect)
    def get(self, request, form: ThreadForm=None):
        page = request.GET.get(PARAM_PAGE, DEFAULT_PAGE)

        params = self.get_context_data(request=request)

        if not form:
            form = ThreadForm(error_class=PlainErrorList,
                              initial={FORM_TAGS: self.tag_name})

        self.settings_manager = get_settings_manager(request)

        threads = self.get_threads()

        order = request.GET.get(PARAM_ORDER, ORDER_BUMP)
        if order == ORDER_BUMP:
            threads = threads.order_by('-bump_time')
        else:
            threads = threads.filter(replies__opening=True)\
                .order_by('-replies__pub_time')
        threads = threads.distinct()

        paginator = get_paginator(threads, settings.get_int(
            SECTION_VIEW, 'ThreadsPerPage'))
        paginator.current_page = int(page)

        try:
            threads = paginator.page(page).object_list
        except EmptyPage:
            raise Http404()

        params[PARAMETER_THREADS] = threads
        params[CONTEXT_FORM] = form
        params[PARAMETER_RSS_URL] = self.get_rss_url()

        paginator.set_url(self.get_reverse_url(), request.GET.dict())
        params.update(self.get_page_context(paginator, page))

        return render(request, TEMPLATE, params)

    @method_decorator(csrf_protect)
    def post(self, request):
        if PARAMETER_METHOD in request.POST:
            self.dispatch_method(request)

            return self.get_reverse_url()

        form = ThreadForm(request.POST, request.FILES,
                          error_class=PlainErrorList)
        form.session = request.session

        if form.is_valid():
            return Post.objects.create_from_form(request, form, None)
        if form.need_to_ban:
            # Ban user because he is suspected to be a bot
            self._ban_current_user(request)

        return self.get(request, form)

    def get_reverse_url(self):
        return reverse('index')

    def get_threads(self):
        """
        Gets list of threads that will be shown on a page.
        """

        threads = Thread.objects\
            .exclude(tags__in=self.settings_manager.get_hidden_tags())
        if self.settings_manager.get_setting(SETTING_ONLY_FAVORITES):
            fav_tags = self.settings_manager.get_fav_tags()
            if len(fav_tags) > 0:
                threads = threads.filter(tags__in=fav_tags)

        return threads

    def get_rss_url(self):
        return self.get_reverse_url() + 'rss/'

    def toggle_fav(self, request):
        settings_manager = get_settings_manager(request)
        settings_manager.set_setting(SETTING_ONLY_FAVORITES,
                not settings_manager.get_setting(SETTING_ONLY_FAVORITES, False))