''' non-interactive pages '''
from io import BytesIO
from uuid import uuid4
from PIL import Image

from django.contrib.auth.decorators import login_required
from django.core.files.base import ContentFile
from django.core.paginator import Paginator
from django.http import HttpResponseNotFound
from django.shortcuts import redirect
from django.template.response import TemplateResponse
from django.utils import timezone
from django.utils.decorators import method_decorator
from django.views import View

from bookwyrm import forms, models
from bookwyrm.activitypub import ActivitypubResponse
from bookwyrm.settings import PAGE_LENGTH
from .helpers import get_activity_feed, get_user_from_username, is_api_request
from .helpers import is_blocked, object_visible_to_user


# pylint: disable= no-self-use
class User(View):
    ''' user profile page '''
    def get(self, request, username):
        ''' profile page for a user '''
        try:
            user = get_user_from_username(request.user, username)
        except models.User.DoesNotExist:
            return HttpResponseNotFound()

        # make sure we're not blocked
        if is_blocked(request.user, user):
            return HttpResponseNotFound()

        if is_api_request(request):
            # we have a json request
            return ActivitypubResponse(user.to_activity())
        # otherwise we're at a UI view

        try:
            page = int(request.GET.get('page', 1))
        except ValueError:
            page = 1

        shelf_preview = []

        # only show other shelves that should be visible
        shelves = user.shelf_set
        is_self = request.user.id == user.id
        if not is_self:
            follower = user.followers.filter(id=request.user.id).exists()
            if follower:
                shelves = shelves.filter(privacy__in=['public', 'followers'])
            else:
                shelves = shelves.filter(privacy='public')

        for user_shelf in shelves.all():
            if not user_shelf.books.count():
                continue
            shelf_preview.append({
                'name': user_shelf.name,
                'local_path': user_shelf.local_path,
                'books': user_shelf.books.all()[:3],
                'size': user_shelf.books.count(),
            })
            if len(shelf_preview) > 2:
                break

        # user's posts
        activities = get_activity_feed(
            request.user,
            queryset=user.status_set.select_subclasses(),
        )
        paginated = Paginator(activities, PAGE_LENGTH)
        goal = models.AnnualGoal.objects.filter(
            user=user, year=timezone.now().year).first()
        if not object_visible_to_user(request.user, goal):
            goal = None
        data = {
            'title': user.name,
            'user': user,
            'is_self': is_self,
            'shelves': shelf_preview,
            'shelf_count': shelves.count(),
            'activities': paginated.page(page),
            'goal': goal,
        }

        return TemplateResponse(request, 'user/user.html', data)

class Followers(View):
    ''' list of followers view '''
    def get(self, request, username):
        ''' list of followers '''
        try:
            user = get_user_from_username(request.user, username)
        except models.User.DoesNotExist:
            return HttpResponseNotFound()

        # make sure we're not blocked
        if is_blocked(request.user, user):
            return HttpResponseNotFound()

        if is_api_request(request):
            return ActivitypubResponse(
                user.to_followers_activity(**request.GET))

        data = {
            'title': '%s: followers' % user.name,
            'user': user,
            'is_self': request.user.id == user.id,
            'followers': user.followers.all(),
        }
        return TemplateResponse(request, 'user/followers.html', data)

class Following(View):
    ''' list of following view '''
    def get(self, request, username):
        ''' list of followers '''
        try:
            user = get_user_from_username(request.user, username)
        except models.User.DoesNotExist:
            return HttpResponseNotFound()

        # make sure we're not blocked
        if is_blocked(request.user, user):
            return HttpResponseNotFound()

        if is_api_request(request):
            return ActivitypubResponse(
                user.to_following_activity(**request.GET))

        data = {
            'title': '%s: following' % user.name,
            'user': user,
            'is_self': request.user.id == user.id,
            'following': user.following.all(),
        }
        return TemplateResponse(request, 'user/following.html', data)


@method_decorator(login_required, name='dispatch')
class EditUser(View):
    ''' edit user view '''
    def get(self, request):
        ''' edit profile page for a user '''
        data = {
            'title': 'Edit profile',
            'form': forms.EditUserForm(instance=request.user),
            'user': request.user,
        }
        return TemplateResponse(request, 'preferences/edit_user.html', data)

    def post(self, request):
        ''' les get fancy with images '''
        form = forms.EditUserForm(
            request.POST, request.FILES, instance=request.user)
        if not form.is_valid():
            data = {'form': form, 'user': request.user}
            return TemplateResponse(request, 'preferences/edit_user.html', data)

        user = form.save(commit=False)

        if 'avatar' in form.files:
            # crop and resize avatar upload
            image = Image.open(form.files['avatar'])
            image = crop_avatar(image)

            # set the name to a hash
            extension = form.files['avatar'].name.split('.')[-1]
            filename = '%s.%s' % (uuid4(), extension)
            user.avatar.save(filename, image)
        user.save()

        return redirect(user.local_path)


def crop_avatar(image):
    ''' reduce the size and make an avatar square '''
    target_size = 120
    width, height = image.size
    thumbnail_scale = height / (width / target_size) if height > width \
        else width / (height / target_size)
    image.thumbnail([thumbnail_scale, thumbnail_scale])
    width, height = image.size

    width_diff = width - target_size
    height_diff = height - target_size
    cropped = image.crop((
        int(width_diff / 2),
        int(height_diff / 2),
        int(width - (width_diff / 2)),
        int(height - (height_diff / 2))
    ))
    output = BytesIO()
    cropped.save(output, format=image.format)
    return ContentFile(output.getvalue())