# Copyright (C) 2021 by BDE ENS Paris-Saclay
# SPDX-License-Identifier: GPL-3.0-or-later

import os
import zipfile
from io import BytesIO

from django.contrib.auth.mixins import LoginRequiredMixin
from django.core.mail import mail_managers
from django.http import HttpResponse
from django.views.generic.detail import DetailView
from django.views.generic.edit import FormView
from photologue.models import Gallery
from photologue.views import GalleryArchiveIndexView, GalleryYearArchiveView
from taggit.models import Tag

from .forms import UploadForm


class TagDetail(LoginRequiredMixin, DetailView):
    model = Tag

    def get_context_data(self, **kwargs):
        """
        Insert the single object into the context dict.
        """
        current_tag = self.get_object().slug
        context = super().get_context_data(**kwargs)
        context['galleries'] = Gallery.objects.on_site().is_public() \
            .filter(extended__tags__slug=current_tag) \
            .order_by('-extended__date_start')
        return context


class CustomGalleryArchiveIndexView(GalleryArchiveIndexView):
    """
    Override to use event date
    """
    date_field = 'extended__date_start'
    uses_datetime_field = False  # Fix related object access


class CustomGalleryYearArchiveView(GalleryYearArchiveView):
    """
    Override to use event date
    """
    date_field = 'extended__date_start'
    uses_datetime_field = False  # Fix related object access


class CustomGalleryDetailView(DetailView):
    """
    Custom gallery detail view to filter on photo owner
    """
    queryset = Gallery.objects.on_site().is_public()

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

        # Query with extended and owner to reduce database lag
        context['photos'] = self.object.public().select_related('extended__owner')

        # List owners
        context['owners'] = []
        for photo in context['photos']:
            if hasattr(photo, 'extended') and photo.extended.owner not in context['owners']:
                context['owners'].append(photo.extended.owner)

        # Filter on owner
        if 'owner' in self.kwargs:
            context['photos'] = context['photos'].filter(extended__owner__id=self.kwargs['owner'])

        return context


class GalleryDownload(LoginRequiredMixin, DetailView):
    model = Gallery

    def get(self, request, *args, **kwargs):
        """
        Download a zip file of the gallery on GET request.
        """
        # Create zip file with pictures
        gallery = self.get_object()
        byte_data = BytesIO()
        zip_file = zipfile.ZipFile(byte_data, "w")
        for photo in gallery.public():
            filename = os.path.basename(os.path.normpath(photo.image.path))
            zip_file.write(photo.image.path, filename)
        zip_file.close()

        # Return zip file
        response = HttpResponse(byte_data.getvalue(), content_type='application/x-zip-compressed')
        response['Content-Disposition'] = f"attachment; filename={gallery.slug}.zip"
        return response


class GalleryUpload(FormView):
    form_class = UploadForm
    template_name = "photologue/upload.html"
    # success_url = '...'  # Replace with your URL or reverse().

    def post(self, request, *args, **kwargs):
        form_class = self.get_form_class()
        form = self.get_form(form_class)
        files = request.FILES.getlist('file_field')
        if form.is_valid():
            for f in files:
                print("upload", f)
            return self.form_valid(form)
        else:
            return self.form_invalid(form)

    def form_valid(self, form):
        """
        Notify moderators about successful upload
        """
        mail_managers(
            subject="New upload",
            message="",  # TODO: put username, gallery and photo names
        )
        return super().form_valid(form)