import hmac
import random
import time

from django.conf import settings
from django.shortcuts import redirect, render

from common.middleware import gate_whitelist


def _under_lockout(request):
    lock_until = request.session.get('lock_until')
    if lock_until and time.time() < lock_until:
        return True
    return False


def _start_lockout(request):
    duration = random.randint(30, 300)
    request.session['lock_until'] = time.time() + duration


@gate_whitelist
def gate(request):
    if request.method == 'POST':
        if _under_lockout(request):
            return render(request, 'landing/gate.html', {
                'error': 'Incorrect password.',
            })

        submitted = request.POST.get('password', '')
        master = settings.PASSWORD or ''
        if hmac.compare_digest(submitted, master):
            request.session['authorized'] = True
            request.session.pop('lock_until', None)
            return redirect('home')
        else:
            _start_lockout(request)
            return render(request, 'landing/gate.html', {
                'error': 'Incorrect password.',
            })

    if request.session.get('authorized'):
        return redirect('home')

    return render(request, 'landing/gate.html')


def home(request):
    return render(request, 'landing/home.html')