''' views for actions you can take in the application '''
from io import BytesIO, TextIOWrapper
import re
from PIL import Image

from django.contrib.auth import authenticate, login, logout
from django.contrib.auth.decorators import login_required
from django.core.files.base import ContentFile
from django.http import HttpResponseBadRequest, HttpResponseNotFound
from django.shortcuts import redirect
from django.template.response import TemplateResponse

from fedireads import forms, models, books_manager, outgoing
from fedireads import goodreads_import
from fedireads.settings import DOMAIN
from fedireads.views import get_user_from_username
from fedireads.books_manager import get_or_create_book


def user_login(request):
    ''' authenticate user login '''
    if request.method == 'GET':
        return redirect('/login')

    register_form = forms.RegisterForm()
    login_form = forms.LoginForm(request.POST)
    if not login_form.is_valid():
        return TemplateResponse(
            request,
            'login.html',
            {'login_form': login_form, 'register_form': register_form}
        )

    username = login_form.data['username']
    username = '%s@%s' % (username, DOMAIN)
    password = login_form.data['password']
    user = authenticate(request, username=username, password=password)
    if user is not None:
        login(request, user)
        return redirect(request.GET.get('next', '/'))
    return TemplateResponse(
        request,
        'login.html',
        {'login_form': login_form, 'register_form': register_form}
    )


def register(request):
    ''' join the server '''
    if request.method == 'GET':
        return redirect('/login')

    form = forms.RegisterForm(request.POST)
    if not form.is_valid():
        return redirect('/register/')

    username = form.data['username']
    email = form.data['email']
    password = form.data['password']

    user = models.User.objects.create_user(username, email, password)
    login(request, user)
    return redirect('/')


@login_required
def user_logout(request):
    ''' done with this place! outa here! '''
    logout(request)
    return redirect('/')


@login_required
def edit_profile(request):
    ''' les get fancy with images '''
    if not request.method == 'POST':
        return redirect('/user/%s' % request.user.localname)

    form = forms.EditUserForm(request.POST, request.FILES)
    if not form.is_valid():
        return redirect('/')

    request.user.name = form.data['name']
    if 'avatar' in form.files:
        # crop and resize avatar upload
        image = Image.open(form.files['avatar'])
        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)
        ContentFile(output.getvalue())
        request.user.avatar.save(
            form.files['avatar'].name,
            ContentFile(output.getvalue())
        )

    request.user.summary = form.data['summary']
    request.user.manually_approves_followers = \
        form.cleaned_data['manually_approves_followers']
    request.user.save()

    outgoing.handle_update_user(request.user)
    return redirect('/user/%s' % request.user.localname)


@login_required
def edit_book(request, book_id):
    ''' edit a book cool '''
    if not request.method == 'POST':
        return redirect('/book/%s' % request.user.localname)

    try:
        book = models.Edition.objects.get(id=book_id)
    except models.Edition.DoesNotExist:
        return HttpResponseNotFound()

    form = forms.EditionForm(request.POST, request.FILES, instance=book)
    if not form.is_valid():
        return redirect(request.headers.get('Referer', '/'))
    form.save()

    outgoing.handle_update_book(request.user, book)
    return redirect('/book/%s' % book.id)


@login_required
def upload_cover(request, book_id):
    ''' upload a new cover '''
    # TODO: alternate covers?
    if not request.method == 'POST':
        return redirect('/book/%s' % request.user.localname)

    try:
        book = models.Edition.objects.get(id=book_id)
    except models.Book.DoesNotExist:
        return HttpResponseNotFound()

    form = forms.CoverForm(request.POST, request.FILES, instance=book)
    if not form.is_valid():
        return redirect(request.headers.get('Referer', '/'))

    book.cover = form.files['cover']
    book.sync_cover = False
    book.save()

    outgoing.handle_update_book(request.user, book)
    return redirect('/book/%s' % book.id)


@login_required
def shelve(request):
    ''' put a  on a user's shelf '''
    book = models.Book.objects.select_subclasses().get(id=request.POST['book'])
    if isinstance(book, models.Work):
        book = book.default_edition

    desired_shelf = models.Shelf.objects.filter(
        identifier=request.POST['shelf'],
        user=request.user
    ).first()

    if request.POST.get('reshelve', True):
        try:
            current_shelf = models.Shelf.objects.get(
                user=request.user,
                edition=book
            )
            outgoing.handle_unshelve(request.user, book, current_shelf)
        except models.Shelf.DoesNotExist:
            # this just means it isn't currently on the user's shelves
            pass
    outgoing.handle_shelve(request.user, book, desired_shelf)
    return redirect('/')


@login_required
def rate(request):
    ''' just a star rating for a book '''
    form = forms.RatingForm(request.POST)
    book_identifier = request.POST.get('book')
    # TODO: better failure behavior
    if not form.is_valid():
        return redirect('/book/%s' % book_identifier)

    rating = form.cleaned_data.get('rating')
    # throws a value error if the book is not found
    book = get_or_create_book(book_identifier)

    outgoing.handle_rate(request.user, book, rating)
    return redirect('/book/%s' % book_identifier)


@login_required
def review(request):
    ''' create a book review '''
    form = forms.ReviewForm(request.POST)
    book_identifier = request.POST.get('book')
    # TODO: better failure behavior
    if not form.is_valid():
        return redirect('/book/%s' % book_identifier)

    # TODO: validation, htmlification
    name = form.cleaned_data.get('name')
    content = form.cleaned_data.get('content')
    rating = form.data.get('rating', None)
    try:
        rating = int(rating)
    except ValueError:
        rating = None

    # throws a value error if the book is not found
    book = get_or_create_book(book_identifier)

    outgoing.handle_review(request.user, book, name, content, rating)
    return redirect('/book/%s' % book_identifier)


@login_required
def quotate(request):
    ''' create a book quotation '''
    form = forms.QuotationForm(request.POST)
    book_identifier = request.POST.get('book')
    if not form.is_valid():
        return redirect('/book/%s' % book_identifier)

    quote = form.cleaned_data.get('quote')
    content = form.cleaned_data.get('content')

    outgoing.handle_quotation(request.user, book_identifier, content, quote)
    return redirect('/book/%s' % book_identifier)


@login_required
def comment(request):
    ''' create a book comment '''
    form = forms.CommentForm(request.POST)
    book_identifier = request.POST.get('book')
    # TODO: better failure behavior
    if not form.is_valid():
        return redirect('/book/%s' % book_identifier)

    # TODO: validation, htmlification
    content = form.data.get('content')

    outgoing.handle_comment(request.user, book_identifier, content)
    return redirect('/book/%s' % book_identifier)


@login_required
def tag(request):
    ''' tag a book '''
    # I'm not using a form here because sometimes "name" is sent as a hidden
    # field which doesn't validate
    name = request.POST.get('name')
    book_identifier = request.POST.get('book')

    outgoing.handle_tag(request.user, book_identifier, name)
    return redirect('/book/%s' % book_identifier)


@login_required
def untag(request):
    ''' untag a book '''
    name = request.POST.get('name')
    book_identifier = request.POST.get('book')

    outgoing.handle_untag(request.user, book_identifier, name)
    return redirect('/book/%s' % book_identifier)


@login_required
def reply(request):
    ''' respond to a book review '''
    form = forms.ReplyForm(request.POST)
    # this is a bit of a formality, the form is just one text field
    if not form.is_valid():
        return redirect('/')
    parent_id = request.POST['parent']
    parent = models.Status.objects.get(id=parent_id)
    outgoing.handle_reply(request.user, parent, form.data['content'])
    return redirect('/')


@login_required
def favorite(request, status_id):
    ''' like a status '''
    status = models.Status.objects.get(id=status_id)
    outgoing.handle_favorite(request.user, status)
    return redirect(request.headers.get('Referer', '/'))


@login_required
def unfavorite(request, status_id):
    ''' like a status '''
    status = models.Status.objects.get(id=status_id)
    outgoing.handle_unfavorite(request.user, status)
    return redirect(request.headers.get('Referer', '/'))

@login_required
def boost(request, status_id):
    ''' boost a status '''
    status = models.Status.objects.get(id=status_id)
    outgoing.handle_boost(request.user, status)
    return redirect(request.headers.get('Referer', '/'))

@login_required
def follow(request):
    ''' follow another user, here or abroad '''
    username = request.POST['user']
    try:
        to_follow = get_user_from_username(username)
    except models.User.DoesNotExist:
        return HttpResponseBadRequest()

    outgoing.handle_follow(request.user, to_follow)
    user_slug = to_follow.localname if to_follow.localname \
        else to_follow.username
    return redirect('/user/%s' % user_slug)


@login_required
def unfollow(request):
    ''' unfollow a user '''
    username = request.POST['user']
    try:
        to_unfollow = get_user_from_username(username)
    except models.User.DoesNotExist:
        return HttpResponseBadRequest()

    outgoing.handle_unfollow(request.user, to_unfollow)
    user_slug = to_unfollow.localname if to_unfollow.localname \
        else to_unfollow.username
    return redirect('/user/%s' % user_slug)


@login_required
def search(request):
    ''' that search bar up top '''
    query = request.GET.get('q')
    if re.match(r'\w+@\w+.\w+', query):
        # if something looks like a username, search with webfinger
        results = [outgoing.handle_account_search(query)]
        template = 'user_results.html'
    else:
        # just send the question over to book search
        results = books_manager.search(query)
        template = 'book_results.html'

    return TemplateResponse(request, template, {'results': results})


@login_required
def clear_notifications(request):
    ''' permanently delete notification for user '''
    request.user.notification_set.filter(read=True).delete()
    return redirect('/notifications')


@login_required
def accept_follow_request(request):
    ''' a user accepts a follow request '''
    username = request.POST['user']
    try:
        requester = get_user_from_username(username)
    except models.User.DoesNotExist:
        return HttpResponseBadRequest()

    try:
        follow_request = models.UserFollowRequest.objects.get(
            user_subject=requester,
            user_object=request.user
        )
    except models.UserFollowRequest.DoesNotExist:
        # Request already dealt with.
        pass
    else:
        outgoing.handle_accept(requester, request.user, follow_request)

    return redirect('/user/%s' % request.user.localname)


@login_required
def delete_follow_request(request):
    ''' a user rejects a follow request '''
    username = request.POST['user']
    try:
        requester = get_user_from_username(username)
    except models.User.DoesNotExist:
        return HttpResponseBadRequest()

    try:
        follow_request = models.UserFollowRequest.objects.get(
            user_subject=requester,
            user_object=request.user
        )
    except models.UserFollowRequest.DoesNotExist:
        return HttpResponseBadRequest()

    outgoing.handle_reject(requester, request.user, follow_request)
    return redirect('/user/%s' % request.user.localname)


@login_required
def import_data(request):
    ''' ingest a goodreads csv '''
    form = forms.ImportForm(request.POST, request.FILES)
    if form.is_valid():
        try:
            job = goodreads_import.create_job(
                request.user,
                TextIOWrapper(
                    request.FILES['csv_file'],
                    encoding=request.encoding)
            )
        except (UnicodeDecodeError, ValueError):
            return HttpResponseBadRequest('Not a valid csv file')
        goodreads_import.start_import(job)
        return redirect('/import_status/%d' % (job.id,))
    return HttpResponseBadRequest()