from django.conf import settings
from django.core.paginator import Paginator
from django.db.models import Q
from django.shortcuts import get_object_or_404, redirect, render
from django.views.generic import DetailView, ListView, TemplateView

from .models import Album, Photo, Redir


class AlbumsList(ListView):
    """Displays a paginated list of public albums."""
    model = Album
    template_name = 'gallery/album_list.html'
    queryset = Album.objects.filter(is_public=True).order_by('-album_date')
    paginate_by = 30


class AlbumDetail(DetailView):
    """Shows a single album and its paginated photos."""
    model = Album
    template_name = 'gallery/album_detail.html'

    def get_object(self, queryset=None):
        return get_object_or_404(Album, slug=self.kwargs.get('album_slug'))

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        photos = self.object.photos.all().order_by('taken_at')

        paginator = Paginator(photos, 30)
        page_obj = paginator.get_page(self.request.GET.get('page'))

        context.update({
            'photos': page_obj.object_list,
            'page_obj': page_obj
        })
        return context



class PhotosList(ListView):
    """Shows all public photos sorted by user-selected ordering."""
    model = Photo
    paginate_by = 30

    def get_queryset(self):
        ordering_options = {
            'latest': '-taken_at',
            'liked': 'likes',
            'popular': '-views'
        }
        order = ordering_options.get(self.request.GET.get('order', 'latest'), '-taken_at')
        return Photo.objects.filter(album__is_public=True).order_by(order).select_related('album')

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context['order'] = self.request.GET.get('order', 'latest')
        return context


class PhotoDetail(DetailView):
    """Shows a single photo and handles liking functionality."""
    model = Photo
    slug_url_kwarg = 'photo_slug'
    template_name = 'gallery/photo_detail.html'

    def get_object(self, queryset=None):
        album_slug = self.kwargs.get('album_slug')
        photo_slug = self.kwargs.get('photo_slug')
        photo = get_object_or_404(Photo, slug=photo_slug, album__slug=album_slug)

        # Track views using session to avoid duplicate counts
        if photo.slug not in self.request.session:
            photo.add_view()
            self.request.session[photo.slug] = 0

        return photo

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context.update({
            "next": self.object.get_next(),
            "prev": self.object.get_prev()
        })
        return context

    def post(self, request, *args, **kwargs):
        photo = self.get_object()

        if request.POST.get("like") == "true" and self.request.session.get(photo.slug) == 0:
            photo.add_like()
            self.request.session[photo.slug] = 1

            if request.user.is_authenticated:
                photo.is_favorite = True
            photo.save()

        return redirect('gallery:photo_url', album_slug=self.kwargs['album_slug'], photo_slug=self.kwargs['photo_slug'])


class About(TemplateView):
    """Static about page."""
    template_name = "gallery/about.html"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["about"] = settings.ABOUT_PAGE_SETTINGS
        return context



class Search(TemplateView):
    """Search view for public albums by name, place or city."""
    template_name = "gallery/search.html"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        query = self.request.GET.get('q', '').strip()
        context['query'] = query

        results = Album.objects.none()
        if query:
            results = Album.objects.filter(
                Q(is_public=True),
                Q(name__icontains=query) |
                Q(location__place__icontains=query) |
                Q(location__city__name__icontains=query)
            ).order_by('-album_date').distinct()

        paginator = Paginator(results, 30)
        page_obj = paginator.get_page(self.request.GET.get('page'))

        context.update({
            'results': page_obj.object_list,
            'page_obj': page_obj,
            'paginator': paginator,
            'is_paginated': page_obj.has_other_pages()
        })
        return context


def redirect_to_album(request, redir_path):
    """Handles redirect logic for shortened/legacy album URLs."""
    redir = get_object_or_404(Redir, path=redir_path)
    return redirect('gallery:album_url', album_slug=redir.album.slug)