from __future__ import unicode_literals
from cStringIO import StringIO
import itertools
import logging
import os
import time
from zipfile import ZipFile, ZipInfo

from django.conf import settings

from django.http import Http404, HttpResponse
from django.shortcuts import render_to_response, redirect, get_object_or_404
from django.template import RequestContext
from django.utils.translation import ugettext_lazy as _

from django.contrib import messages
from django.contrib.admin.views.decorators import staff_member_required
from django.contrib.auth.decorators import login_required

from symposion.sponsorship.forms import SponsorApplicationForm, \
    SponsorDetailsForm, SponsorBenefitsFormSet
from symposion.sponsorship.models import Benefit, Sponsor, SponsorBenefit, \
    SponsorLevel


log = logging.getLogger(__name__)


@login_required
def sponsor_apply(request):
    if request.method == "POST":
        form = SponsorApplicationForm(request.POST, user=request.user)
        if form.is_valid():
            sponsor = form.save()
            if sponsor.sponsor_benefits.all():
                # Redirect user to sponsor_detail to give extra information.
                messages.success(request, _("Thank you for your sponsorship "
                                            "application. Please update your "
                                            "benefit details below."))
                return redirect("sponsor_detail", pk=sponsor.pk)
            else:
                messages.success(request, _("Thank you for your sponsorship "
                                            "application."))
                return redirect("dashboard")
    else:
        form = SponsorApplicationForm(user=request.user)

    return render_to_response("sponsorship/apply.html", {
        "form": form,
    }, context_instance=RequestContext(request))


@login_required
def sponsor_add(request):
    if not request.user.is_staff:
        raise Http404()

    if request.method == "POST":
        form = SponsorApplicationForm(request.POST, user=request.user)
        if form.is_valid():
            sponsor = form.save(commit=False)
            sponsor.active = True
            sponsor.save()
            return redirect("sponsor_detail", pk=sponsor.pk)
    else:
        form = SponsorApplicationForm(user=request.user)

    return render_to_response("sponsorship/add.html", {
        "form": form,
    }, context_instance=RequestContext(request))


@login_required
def sponsor_detail(request, pk):
    sponsor = get_object_or_404(Sponsor, pk=pk)

    if sponsor.applicant != request.user:
        return redirect("sponsor_list")

    formset_kwargs = {
        "instance": sponsor,
        "queryset": SponsorBenefit.objects.filter(active=True)
    }

    if request.method == "POST":

        form = SponsorDetailsForm(request.POST, instance=sponsor)
        formset = SponsorBenefitsFormSet(request.POST, request.FILES, **formset_kwargs)

        if form.is_valid() and formset.is_valid():
            form.save()
            formset.save()

            messages.success(request, "Sponsorship details have been updated")

            return redirect("dashboard")
    else:
        form = SponsorDetailsForm(instance=sponsor)
        formset = SponsorBenefitsFormSet(**formset_kwargs)

    return render_to_response("sponsorship/detail.html", {
        "sponsor": sponsor,
        "form": form,
        "formset": formset,
    }, context_instance=RequestContext(request))


@staff_member_required
def sponsor_export_data(request):
    sponsors = []
    data = ""

    for sponsor in Sponsor.objects.order_by("added"):
        d = {
            "name": sponsor.name,
            "url": sponsor.external_url,
            "level": (sponsor.level.order, sponsor.level.name),
            "description": "",
        }
        for sponsor_benefit in sponsor.sponsor_benefits.all():
            if sponsor_benefit.benefit_id == 2:
                d["description"] = sponsor_benefit.text
        sponsors.append(d)

    def izip_longest(*args):
        fv = None

        def sentinel(counter=([fv] * (len(args) - 1)).pop):
            yield counter()
        iters = [itertools.chain(it, sentinel(), itertools.repeat(fv)) for it in args]
        try:
            for tup in itertools.izip(*iters):
                yield tup
        except IndexError:
            pass

    def pairwise(iterable):
        a, b = itertools.tee(iterable)
        b.next()
        return izip_longest(a, b)

    def level_key(s):
        return s["level"]

    for level, level_sponsors in itertools.groupby(sorted(sponsors, key=level_key), level_key):
        data += "%s\n" % ("-" * (len(level[1]) + 4))
        data += "| %s |\n" % level[1]
        data += "%s\n\n" % ("-" * (len(level[1]) + 4))
        for sponsor, next in pairwise(level_sponsors):
            description = sponsor["description"].strip()
            description = description if description else "-- NO DESCRIPTION FOR THIS SPONSOR --"
            data += "%s\n\n%s" % (sponsor["name"], description)
            if next is not None:
                data += "\n\n%s\n\n" % ("-" * 80)
            else:
                data += "\n\n"

    return HttpResponse(data, content_type="text/plain;charset=utf-8")


@staff_member_required
def sponsor_zip_logo_files(request):
    """Return a zip file of sponsor web and print logos"""

    zip_stringio = StringIO()
    zipfile = ZipFile(zip_stringio, "w")
    try:
        benefits = Benefit.objects.all()
        for benefit in benefits:
            dir_name = benefit.name.lower().replace(" ", "_").replace('/', '_')
            for level in SponsorLevel.objects.all():
                level_name = level.name.lower().replace(" ", "_").replace('/', '_')
                for sponsor in Sponsor.objects.filter(level=level, active=True):
                    sponsor_name = sponsor.name.lower().replace(" ", "_").replace('/', '_')
                    full_dir = "/".join([dir_name, level_name, sponsor_name])
                    for sponsor_benefit in SponsorBenefit.objects.filter(
                        benefit=benefit,
                        sponsor=sponsor,
                        active=True,
                    ).exclude(upload=''):
                        if os.path.exists(sponsor_benefit.upload.path):
                            modtime = time.gmtime(os.stat(sponsor_benefit.upload.path).st_mtime)
                            with open(sponsor_benefit.upload.path, "rb") as f:
                                fname = os.path.split(sponsor_benefit.upload.name)[-1]
                                zipinfo = ZipInfo(filename=full_dir + "/" + fname,
                                                  date_time=modtime)
                                zipfile.writestr(zipinfo, f.read())
                        else:
                            log.debug("No such sponsor file: %s" % sponsor_benefit.upload.path)
    finally:
        zipfile.close()

    response = HttpResponse(zip_stringio.getvalue(),
                            content_type="application/zip")
    prefix = settings.CONFERENCE_URL_PREFIXES[settings.CONFERENCE_ID]
    response['Content-Disposition'] = \
        'attachment; filename="%s_sponsorlogos.zip"' % prefix
    return response