# -*- coding: utf-8 -*-
#
# Copyright © 2012 - 2017 Michal Čihař <michal@cihar.com>
#
# This file is part of Weblate <https://weblate.org/>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.
#

from django.http import HttpResponse, Http404
from django.shortcuts import redirect
from django.core.urlresolvers import reverse
from django.views.decorators.vary import vary_on_cookie
from django.views.decorators.cache import cache_page

from weblate.trans.site import get_site_url
from weblate.lang.models import Language
from weblate.trans.forms import EnageLanguageForm
from weblate.trans.widgets import WIDGETS
from weblate.trans.views.helper import get_project, try_set_language
from weblate.trans.util import render


def widgets_root(request):
    return render(
        request,
        'widgets-root.html',
        {},
    )


def widgets_sorter(widget):
    """Provide better ordering of widgets."""
    return WIDGETS[widget].order


def widgets(request, project):
    obj = get_project(request, project)

    # Parse possible language selection
    form = EnageLanguageForm(obj, request.GET)
    lang = None
    if form.is_valid() and form.cleaned_data['lang'] != '':
        lang = Language.objects.get(code=form.cleaned_data['lang'])

    if lang is None:
        engage_base = reverse('engage', kwargs={'project': obj.slug})
    else:
        engage_base = reverse(
            'engage-lang',
            kwargs={'project': obj.slug, 'lang': lang.code}
        )
    engage_url = get_site_url(engage_base)
    engage_url_track = '{0}?utm_source=widget'.format(engage_url)
    widget_base_url = get_site_url(
        reverse('widgets', kwargs={'project': obj.slug})
    )
    widget_list = []
    for widget_name in sorted(WIDGETS, key=widgets_sorter):
        widget_class = WIDGETS[widget_name]
        if not widget_class.show:
            continue
        color_list = []
        for color in widget_class.colors:
            if lang is None:
                color_url = reverse(
                    'widget-image',
                    kwargs={
                        'project': obj.slug,
                        'widget': widget_name,
                        'color': color,
                        'extension': widget_class.extension,
                    }
                )
            else:
                color_url = reverse(
                    'widget-image-lang',
                    kwargs={
                        'project': obj.slug,
                        'widget': widget_name,
                        'color': color,
                        'lang': lang.code,
                        'extension': widget_class.extension,
                    }
                )
            color_list.append({
                'name': color,
                'url': get_site_url(color_url),
            })
        widget_list.append({
            'name': widget_name,
            'colors': color_list,
        })

    return render(
        request,
        'widgets.html',
        {
            'engage_url': engage_url,
            'engage_url_track': engage_url_track,
            'widget_list': widget_list,
            'widget_base_url': widget_base_url,
            'object': obj,
            'project': obj,
            'image_src': widget_list[0]['colors'][0]['url'],
            'form': form,
        }
    )


@cache_page(3600)
@vary_on_cookie
def render_widget(request, project, widget='287x66', color=None, lang=None,
                  extension='png'):
    # We intentionally skip ACL here to allow widget sharing
    obj = get_project(request, project, skip_acl=True)

    # Handle language parameter
    if lang is not None:
        if 'native' not in request.GET:
            try_set_language(lang)
        lang = Language.objects.try_get(code=lang)
    else:
        try_set_language('en')

    # Get widget class
    try:
        widget_class = WIDGETS[widget]
    except KeyError:
        raise Http404()

    # Construct object
    widget_obj = widget_class(obj, color, lang)

    # Redirect widget
    if hasattr(widget_obj, 'redirect'):
        return redirect(widget_obj.redirect(), permanent=True)

    # Invalid extension
    if extension != widget_obj.extension or color != widget_obj.color:
        kwargs = {
            'project': project,
            'widget': widget,
            'color': widget_obj.color,
            'extension': widget_obj.extension,
        }
        if lang:
            kwargs['lang'] = lang.code
            return redirect('widget-image-lang', permanent=True, **kwargs)
        return redirect('widget-image', permanent=True, **kwargs)

    # Render widget
    widget_obj.render()

    return HttpResponse(
        content_type=widget_obj.content_type,
        content=widget_obj.get_content()
    )
