from django.core.urlresolvers import reverse
from django.core.files import File
from django.core.files.temp import NamedTemporaryFile
from django.core.paginator import EmptyPage
from django.db import transaction
from django.http import Http404
from django.shortcuts import render, redirect
from django.utils.decorators import method_decorator
from django.views.decorators.csrf import csrf_protect

from boards import utils, settings
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, Ban
from boards.views.banned import BannedView
from boards.views.base import BaseBoardView, CONTEXT_FORM
from boards.views.posting_mixin import PostMixin
from boards.views.mixins import FileUploadMixin, PaginatedMixin,\
        DispatcherMixin, PARAMETER_METHOD

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_MAX_FILE_SIZE = 'max_file_size'
PARAMETER_RSS_URL = 'rss_url'
PARAMETER_MAX_FILES = 'max_files'

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

FORM_TAGS = 'tags'


class AllThreadsView(PostMixin, FileUploadMixin, 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('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('order', 'bump')
        if order == 'bump':
            threads = threads.order_by('-bump_time')
        else:
            threads = threads.filter(replies__opening=True)\
                .order_by('-replies__pub_time')
        filter = request.GET.get('filter')
        threads = threads.distinct()

        paginator = get_paginator(threads,
                                  settings.get_int('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_MAX_FILE_SIZE] = self.get_max_upload_size()
        params[PARAMETER_RSS_URL] = self.get_rss_url()
        params[PARAMETER_MAX_FILES] = settings.get_int('Forms', 'MaxFileCount')

        paginator.set_url(self.get_reverse_url(), request.GET.dict())
        self.get_page_context(paginator, params, 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 redirect('index')  # FIXME Different for different modes

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

        if form.is_valid():
            return self.create_thread(request, form)
        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_page_context(self, paginator, params, page):
        """
        Get pagination context variables
        """

        params[PARAMETER_PAGINATOR] = paginator
        current_page = paginator.page(int(page))
        params[PARAMETER_CURRENT_PAGE] = current_page
        self.set_page_urls(paginator, params)

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

    @transaction.atomic
    def create_thread(self, request, form: ThreadForm, html_response=True):
        """
        Creates a new thread with an opening post.
        """

        ip = utils.get_client_ip(request)
        is_banned = Ban.objects.filter(ip=ip).exists()

        if is_banned:
            if html_response:
                return redirect(BannedView().as_view())
            else:
                return

        data = form.cleaned_data

        title = form.get_title()
        text = data[FORM_TEXT]
        files = form.get_files()
        file_urls = form.get_file_urls()
        images = form.get_images()

        text = self._remove_invalid_links(text)

        tags = data[FORM_TAGS]
        monochrome = form.is_monochrome()

        post = Post.objects.create_post(title=title, text=text, files=files,
                                        ip=ip, tags=tags,
                                        tripcode=form.get_tripcode(),
                                        monochrome=monochrome, images=images,
                                        file_urls=file_urls)

        if form.is_subscribe():
            settings_manager = get_settings_manager(request)
            settings_manager.add_or_read_fav_thread(post)

        if html_response:
            return redirect(post.get_absolute_url())

    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))