from django.http import HttpResponse, Http404, HttpResponseRedirect
from django.template import loader 
from django.shortcuts import render, get_object_or_404
from django.urls import reverse

from .models import Question, Choice

def index(request):
    latest_question_list = Question.objects.order_by('-pub_date')[:5]
    context = {
        "latest_question_list": latest_question_list,
    }
    return render(request, "polls/index.html", context)

def detail(request, question_id):
    try:
        question = Question.objects.get(pk=question_id)
    except Question.DoesNotExist:
        raise Http404("Question does not exist!")

    return render(request, "polls/details.html", {"question": question})


def results(request, question_id):
    question = get_object_or_404(Question, pk=question_id)
    return render(request, 'polls/results.html', {'question': question})

def vote(request, question_id):
    question = get_object_or_404(Question, pk=question_id)
    try:
        selected_choice = question.choice_set.get(pk=request.POST["choice"])
    except (KeyError, Choice.DoesNotExist):
        return render(request, "polls/details.html", {
            "question": question,
            "error_message": "You didn't select a choice!"
        })
    else:
        selected_choice.votes += 1
        selected_choice.save()

        return HttpResponseRedirect(reverse("polls:results", args=(question.id,)))