from django.shortcuts import render
from django.views.generic import ListView, DetailView, RedirectView
from django.views.generic.edit import UpdateView, CreateView, DeleteView, ProcessFormView, FormMixin
from django.forms.models import modelform_factory
from django.forms import CheckboxSelectMultiple
from django.core.urlresolvers import reverse_lazy
from django.contrib.auth.forms import AuthenticationForm
from django.http import HttpResponseRedirect
from django.utils import timezone
from django import forms


from core.views import CanViewMixin, CanEditMixin, CanEditPropMixin
from subscription.models import Subscriber
from accounting.models import Customer, Product
from counter.models import Counter

class GetUserForm(forms.Form):
    """
    The Form class aims at providing a valid user_id field in its cleaned data, in order to pass it to some view,
    reverse function, or any other use.

    The Form implements a nice JS widget allowing the user to type a customer account id, or search the database with
    some nickname, first name, or last name (TODO)
    """
    code = forms.CharField(label="Code", max_length=64, required=False)
    id = forms.IntegerField(label="ID", required=False)
# TODO: add a nice JS widget to search for users

    def clean(self):
        cleaned_data = super(GetUserForm, self).clean()
        user = None
        if cleaned_data['code'] != "":
            user = Customer.objects.filter(account_id=cleaned_data['code']).first()
        elif cleaned_data['id'] is not None:
            user = Customer.objects.filter(user=cleaned_data['id']).first()
        if user is None:
            raise forms.ValidationError("User not found")
        cleaned_data['user_id'] = user.user.id
        return cleaned_data

class CounterMain(DetailView, ProcessFormView, FormMixin):
    """
    The public (barman) view
    """
    model = Counter
    template_name = 'counter/counter_main.jinja'
    pk_url_kwarg = "counter_id"
    form_class = GetUserForm # Form to enter a client code and get the corresponding user id

    def get_context_data(self, **kwargs):
        """
        We handle here the login form for the barman

        Also handle the timeout
        """
        if self.request.method == 'POST':
            self.object = self.get_object()
        kwargs = super(CounterMain, self).get_context_data(**kwargs)
# TODO: make some checks on the counter type, in order not to make the AuthenticationForm if there is no need to
        kwargs['login_form'] = AuthenticationForm()
        kwargs['form'] = self.get_form()
        kwargs['barmen'] = Counter.get_barmen_list(self.object.id)
        return kwargs

    def form_valid(self, form):
        """
        We handle here the redirection, passing the user id of the asked customer
        """
        self.kwargs['user_id'] = form.cleaned_data['user_id']
        return super(CounterMain, self).form_valid(form)


    def get_success_url(self):
        return reverse_lazy('counter:click', args=self.args, kwargs=self.kwargs)

class BasketForm(forms.Form):
    def __init__(self, *args, **kwargs):
        print(kwargs)
        super(BasketForm, self).__init__(*args, **kwargs)
        for p in kwargs['initial']['counter'].products.all(): # TODO: filter on the allowed products for this counter
            self.fields[p.id] = forms.IntegerField(label=p.name, required=False)
            # TODO ^: add some extra infos for the products (price, or ID to load infos dynamically)

    def clean(self):
        cleaned_data = super(BasketForm, self).clean()
        total = 0
        for pid,q in cleaned_data.items():
            p = Product.objects.filter(id=pid).first()
            total += (q or 0)*p.selling_price
        print(total)

class CounterClick(DetailView):
    """
    The click view
    This is a detail view not to have to worry about loading the counter
    Everything is made by hand in the post method
    """
    model = Counter
    template_name = 'counter/counter_click.jinja'
    pk_url_kwarg = "counter_id"

    def get(self, request, *args, **kwargs):
        """Simple get view"""
        self.customer = Customer.objects.filter(user__id=self.kwargs['user_id']).first()
        ret = super(CounterClick, self).get(request, *args, **kwargs)
        if len(Counter.get_barmen_list(self.object.id)) < 1: # Check that at least one barman is logged in
            return self.cancel(request) # Otherwise, go to main view
        if 'basket' not in request.session.keys(): # Init the basket session entry
            request.session['basket'] = {}
        return ret

    def post(self, request, *args, **kwargs):
        """ Handle the many possibilities of the post request """
        self.object = self.get_object()
        self.customer = Customer.objects.filter(user__id=self.kwargs['user_id']).first()
        if len(Counter.get_barmen_list(self.object.id)) < 1: # Check that at least one barman is logged in
            return self.cancel(request)
        if 'basket' not in request.session.keys():
            request.session['basket'] = {}

        if 'add_product' in request.POST['action']:
            self.add_product(request)
        elif 'del_product' in request.POST['action']:
            self.del_product(request)
        elif 'cancel' in request.POST['action']:
            return self.cancel(request)
        elif 'finish' in request.POST['action']:
            return self.finish(request)
        context = self.get_context_data(object=self.object)
        return self.render_to_response(context)

    def add_product(self, request):
        """ Add a product to the basket """
        pid = str(request.POST['product_id'])
        if pid in request.session['basket']:
            request.session['basket'][pid] += 1
        else:
            request.session['basket'][pid] = 1
        request.session.modified = True

    def del_product(self, request):
        """ Delete a product from the basket """
        pid = str(request.POST['product_id'])
        if pid in request.session['basket']:
            request.session['basket'][pid] -= 1
            if request.session['basket'][pid] <= 0:
                del request.session['basket'][pid]
        else:
            request.session['basket'][pid] = 0
        request.session.modified = True

    def finish(self, request):
        """ Finish the click session, and validate the basket """
        # TODO: handle the basket
        kwargs = {'counter_id': self.object.id}
        del request.session['basket']
        return HttpResponseRedirect(reverse_lazy('counter:details', args=self.args, kwargs=kwargs))

    def cancel(self, request):
        """ Cancel the click session """
        kwargs = {'counter_id': self.object.id}
        request.session.pop('basket', None)
        return HttpResponseRedirect(reverse_lazy('counter:details', args=self.args, kwargs=kwargs))

    def get_context_data(self, **kwargs):
        """ Add customer to the context """
        kwargs = super(CounterClick, self).get_context_data(**kwargs)
        kwargs['customer'] = self.customer
        return kwargs

class CounterLogin(RedirectView):
    """
    Handle the login of a barman

    Logged barmen are stored in the class-wide variable 'barmen_session', in the Counter model
    """
    permanent = False
    def post(self, request, *args, **kwargs):
        """
        Register the logged user as barman for this counter
        """
        self.counter_id = kwargs['counter_id']
        form = AuthenticationForm(request, data=request.POST)
        if form.is_valid():
            user = Subscriber.objects.filter(username=form.cleaned_data['username']).first()
            if self.counter_id not in Counter.barmen_session.keys():
                Counter.barmen_session[self.counter_id] = {'users': {user.id}, 'time': timezone.now()}
            else:
                Counter.barmen_session[self.counter_id]['users'].add(user.id)
        else:
            print("Error logging the barman") # TODO handle that nicely
        return super(CounterLogin, self).post(request, *args, **kwargs)

    def get_redirect_url(self, *args, **kwargs):
        return reverse_lazy('counter:details', args=args, kwargs=kwargs)

class CounterLogout(RedirectView):
    permanent = False
    def post(self, request, *args, **kwargs):
        """
        Unregister the user from the barman
        """
        self.counter_id = kwargs['counter_id']
        Counter.barmen_session[str(self.counter_id)]['users'].remove(int(request.POST['user_id']))
        return super(CounterLogout, self).post(request, *args, **kwargs)

    def get_redirect_url(self, *args, **kwargs):
        return reverse_lazy('counter:details', args=args, kwargs=kwargs)

## Counter admin views

class CounterListView(CanViewMixin, ListView):
    """
    A list view for the admins
    """
    model = Counter
    template_name = 'counter/counter_list.jinja'

class CounterEditView(CanEditMixin, UpdateView):
    """
    Edit a counter's main informations (for the counter's admin)
    """
    model = Counter
    form_class = modelform_factory(Counter, fields=['name', 'club', 'type', 'products'],
            widgets={'products':CheckboxSelectMultiple})
    pk_url_kwarg = "counter_id"
    template_name = 'counter/counter_edit.jinja'

class CounterCreateView(CanEditMixin, CreateView):
    """
    Create a counter (for the admins)
    """
    model = Counter
    form_class = modelform_factory(Counter, fields=['name', 'club', 'type', 'products'],
            widgets={'products':CheckboxSelectMultiple})
    template_name = 'counter/counter_edit.jinja'

class CounterDeleteView(CanEditMixin, DeleteView):
    """
    Delete a counter (for the admins)
    """
    model = Counter
    pk_url_kwarg = "counter_id"
    template_name = 'core/delete_confirm.jinja'
    success_url = reverse_lazy('counter:admin_list')