import os

from django.http import HttpResponse, HttpResponseRedirect, Http404
from django.utils.translation import ugettext as _
from django.utils import simplejson
from django.core.cache import cache
from django.core.urlresolvers import reverse
from forum.views.admin import admin_tools_page, admin_page
from forms import ExporterForm
from threading import Thread

from exporter import export, CACHE_KEY, EXPORT_STEPS, LAST_BACKUP


@admin_tools_page(_('exporter'), _('XML data export'))
def exporter(request):
    state = cache.get(CACHE_KEY)

    if state and state['running']:
        return HttpResponseRedirect(reverse('exporter_running'))

    if request.method == 'POST':
        form = ExporterForm(request.POST)

        if form.is_valid():
            thread = Thread(target=export, args=[form.cleaned_data])
            thread.setDaemon(True)
            thread.start()

            return HttpResponseRedirect(reverse('exporter_running'))
    else:
        form = ExporterForm()

    return ('modules/exporter/exporter.html', {
        'form': form
    })

@admin_page
def running(request):
    state = cache.get(CACHE_KEY)
    if state is None:
        return HttpResponseRedirect(reverse('admin_tools', args=[_('exporter')]))

    return ('modules/exporter/running.html', {
        'steps': EXPORT_STEPS
    })

def state(request):
    return HttpResponse(simplejson.dumps(cache.get(CACHE_KEY)), mimetype="application/json")

@admin_page
def download(request):
    fname = LAST_BACKUP

    if not os.path.exists(fname):
        raise Http404

    response = HttpResponse(open(fname, 'rb').read(), content_type='application/x-gzip')
    response['Content-Length'] = os.path.getsize(fname)
    response['Content-Disposition'] = 'attachment; filename=backup.tar.gz'
    return response