from django.http import HttpResponseRedirect
from django.views.generic.detail import DetailView
from django.views.generic.list import ListView
from django.views.generic.edit import UpdateView
from django.utils.translation import ugettext_lazy as _
from django.urls import reverse, reverse_lazy
from django.db.models import Count
from django.db.models import Q
from django import forms

from django.contrib.auth.mixins import (LoginRequiredMixin,
                                        PermissionRequiredMixin)

from crispy_forms.helper import FormHelper
from crispy_forms.layout import Layout, Field, Div, HTML
from crispy_forms.bootstrap import AppendedText

from taggit.models import Tag
from rp.forms import TagMultipleChoiceField

from rp.models import Article


class ArticleFilterMixin:
    """
    This mixin allows to filter views using various parameters in the query
    string.
    """
    archive = 'both'
    quote = 'both'
    speak = 'both'

    def get_queryset(self):
        qs = super().get_queryset()
        # Tags filtering
        self.quote = self.request.GET.get('quote', self.quote)
        self.speak = self.request.GET.get('speak', self.speak)
        self.archive = self.request.GET.get('archive', self.archive)

        if self.speak != 'both':
            if self.speak == 'true':
                qs = qs.filter(speak=True)
            else:
                qs = qs.filter(speak=False)

        if self.quote != 'both':
            if self.quote == 'true':
                qs = qs.filter(quote=True)
            else:
                qs = qs.filter(quote=False)

        if self.archive != 'both':
            if self.archive == 'true':
                qs = qs.filter(archive=True)
            else:
                qs = qs.filter(archive=False)

        search_keywords = self.request.GET.get('q', '')
        if search_keywords != '':
            qs = qs.filter(Q(title__icontains=search_keywords)
                           | Q(extracts__icontains=search_keywords))

        return qs

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)

        context["search"] = self.request.GET.get('q', '')
        context["archive"] = self.request.GET.get('archive', self.archive)
        context["speak"] = self.request.GET.get('speak', self.speak)
        context["quote"] = self.request.GET.get('quote', self.quote)

        return context


class ArticleList(ArticleFilterMixin, ListView):
    model = Article
    paginate_by = 10
    template_name = "rp/article_list_public.html"
    filter_lang = None
    filter_tag = None
    archive = 'false'  # We do not want to display archived items by default

    def get_queryset(self):
        qs = super().get_queryset()

        if self.filter_lang in ["EN", "FR"]:
            qs = qs.filter(lang=self.filter_lang)
        else:
            qs = qs.filter()

        filter_tag = self.kwargs.get("filter_tag", self.filter_tag)
        if filter_tag is not None:
            qs = qs.filter(tags__name__in=[filter_tag])

        return qs.order_by('-created_at')

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)

        qs = Tag.objects.annotate(
                num_times=Count('taggit_taggeditem_items')).all()
        qs = qs.order_by('-num_times')
        context["tags"] = qs

        return context


class ArticleListFlux(LoginRequiredMixin, ArticleFilterMixin, ListView):
    model = Article
    paginate_by = 10

    def get_queryset(self):
        filter_view = self.kwargs.get("filter_view", "draft")
        qs = super().get_queryset()

        if filter_view in ["published", "draft", "rejected"]:
            qs = qs.filter(status=filter_view.upper())
        else:
            qs = qs.filter(status="NEW")

        return qs.order_by('-created_at')

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["filter_view"] = self.kwargs.get("filter_view", "draft")
        context["nb_draft"] = Article.objects.filter(status="DRAFT").count()
        return context


class ArticleDetailView(LoginRequiredMixin, DetailView):
    model = Article
    preview = False

    def get_context_data(self, **kwargs):
        context = super(ArticleDetailView, self).get_context_data(**kwargs)
        context['is_preview'] = self.preview
        return context


class ArticleEdit(LoginRequiredMixin, PermissionRequiredMixin, UpdateView):
    model = Article
    permission_required = 'rp.can_edit'
    raise_exception = True

    fields = ['screenshot', 'url', 'lang', 'title', 'tags', 'extracts',
              'quote', 'speak', 'archive']
    success_url = reverse_lazy("rp:article-list")

    def get(self, request, **kwargs):
        self.object = self.get_object()

        if 'fetch_content' in self.request.GET:
            self.object.fetch_content()
        elif 'fetch_image' in self.request.GET:
            self.object.fetch_image()
        elif 'fetch_metadata' in self.request.GET:
            self.object.fetch_metadata()

        context = self.get_context_data(object=self.object)
        return self.render_to_response(context)

    def form_valid(self, form):
        self.object = form.save(commit=False)

        if "preview" in self.request.POST:
            self.success_url = reverse("rp:article-preview", args=[self.object.id])
        elif "view" in self.request.POST:
            self.success_url = reverse("rp:article-view", args=[self.object.id])
        elif "publish" in self.request.POST:
            self.object.publish()
        self.object.save()

        return HttpResponseRedirect(self.get_success_url())

    def get_form(self, form_class=None):
        form = super().get_form(form_class)
        form.fields["screenshot"].widget = forms.widgets.FileInput()

        form.helper = FormHelper()
        form.helper.form_tag = False

        # Change the layout of the tags field
        form.fields["tags"] = TagMultipleChoiceField(
            queryset=Tag.objects.all(), required=False)

        left_layout = Div(
            Div(
                Field('title', wrapper_class='col-sm-10'),
                Field('lang', wrapper_class='col-sm-2'),
                css_class="row"),
            AppendedText(
                'url',
                _('<a href="%s">Go to link</a>') % form.initial['url']),
            'tags',
            'extracts',
            css_class="col-sm-8")

        right_layout = Div(
            'screenshot',
            HTML(
                """
                {% if form.screenshot.value %}
                <img class="img-responsive mb-4"
                     src="/media/{{ form.screenshot.value }}">
                {% endif %}
                """
            ),
            css_class="col-sm-4")

        form.helper.layout = Layout(
            Div(left_layout, right_layout, css_class="row"))

        return form