from django.db import transaction
from django.shortcuts import render, redirect
from django.utils import timezone
from django.utils.decorators import method_decorator
from django.views.decorators.csrf import csrf_protect

from boards.abstracts.settingsmanager import get_settings_manager, \
    SETTING_USERNAME, SETTING_LAST_NOTIFICATION_ID, SETTING_IMAGE_VIEWER, \
    SETTING_SUBSCRIBE_BY_DEFAULT
from boards.middlewares import SESSION_TIMEZONE
from boards.views.base import BaseBoardView, CONTEXT_FORM
from boards.forms import SettingsForm, PlainErrorList
from boards import settings
from boards.models import Attachment

FORM_THEME = 'theme'
FORM_USERNAME = 'username'
FORM_TIMEZONE = 'timezone'
FORM_IMAGE_VIEWER = 'image_viewer'
FORM_SUBSCRIBE = 'subscribe_by_default'

CONTEXT_HIDDEN_TAGS = 'hidden_tags'

TEMPLATE = 'boards/settings.html'


class SettingsView(BaseBoardView):
    @method_decorator(csrf_protect)
    def get(self, request):
        params = dict()
        settings_manager = get_settings_manager(request)

        selected_theme = settings_manager.get_theme()

        form = SettingsForm(
            initial={
                FORM_THEME: selected_theme,
                FORM_IMAGE_VIEWER: settings_manager.get_setting(
                    SETTING_IMAGE_VIEWER,
                    default=settings.get('View', 'DefaultImageViewer')),
                FORM_USERNAME: settings_manager.get_setting(SETTING_USERNAME),
                FORM_TIMEZONE: request.session.get(
                    SESSION_TIMEZONE, timezone.get_current_timezone()),
                FORM_SUBSCRIBE: settings_manager.get_setting(SETTING_SUBSCRIBE_BY_DEFAULT, False)
            },
            error_class=PlainErrorList)

        params[CONTEXT_FORM] = form
        params[CONTEXT_HIDDEN_TAGS] = settings_manager.get_hidden_tags()

        return render(request, TEMPLATE, params)

    @method_decorator(csrf_protect)
    def post(self, request):
        settings_manager = get_settings_manager(request)

        with transaction.atomic():
            form = SettingsForm(request.POST, error_class=PlainErrorList)

            if form.is_valid():
                selected_theme = form.cleaned_data[FORM_THEME]
                username = form.cleaned_data[FORM_USERNAME].lower()

                settings_manager.set_theme(selected_theme)
                settings_manager.set_setting(SETTING_IMAGE_VIEWER,
                                             form.cleaned_data[FORM_IMAGE_VIEWER])
                settings_manager.set_setting(SETTING_SUBSCRIBE_BY_DEFAULT, form.cleaned_data[SETTING_SUBSCRIBE_BY_DEFAULT])

                old_username = settings_manager.get_setting(SETTING_USERNAME)
                if username != old_username:
                    settings_manager.set_setting(SETTING_USERNAME, username)
                    settings_manager.set_setting(SETTING_LAST_NOTIFICATION_ID, None)

                request.session[SESSION_TIMEZONE] = form.cleaned_data[FORM_TIMEZONE]

                return redirect('settings')
            else:
                params = dict()

                params[CONTEXT_FORM] = form
                params[CONTEXT_HIDDEN_TAGS] = settings_manager.get_hidden_tags()

                return render(request, TEMPLATE, params)