from django.shortcuts import render, redirect
from django.contrib.auth import login, logout, get_user_model
from django.contrib.auth.decorators import login_required
from django.contrib import messages
from django.contrib.sites.shortcuts import get_current_site
from django.utils.encoding import force_bytes, force_str
from django.utils.http import urlsafe_base64_encode, urlsafe_base64_decode
from django.template.loader import render_to_string
from django.core.mail import EmailMessage

from .models import Profile
from .forms import SignupForm
from .tokens import account_activation_token

User = get_user_model()

def home(request):
    if request.user.is_authenticated:
        return redirect('dashboard')
    return render(request, 'core/index.html')

def signup(request):
    if request.user.is_authenticated:
        return redirect('dashboard')
    if request.method == 'POST':
        form = SignupForm(request.POST)
        if form.is_valid():
            user = form.save(commit=False)
            user.is_active = False
            user.save()
            
            # Send activation email
            current_site = get_current_site(request)
            mail_subject = 'Activate your Referral Rewards account.'
            message = render_to_string('core/emails/activation_email.html', {
                'user': user,
                'domain': current_site.domain,
                'protocol': 'https' if request.is_secure() else 'http',
                'uid': urlsafe_base64_encode(force_bytes(user.pk)),
                'token': account_activation_token.make_token(user),
            })
            to_email = form.cleaned_data.get('email')
            email = EmailMessage(
                mail_subject, message, to=[to_email]
            )
            try:
                email.send()
                messages.success(request, 'Please confirm your email address to complete the registration. Check your inbox.')
            except Exception as e:
                messages.error(request, f'Error sending email: {str(e)}. Please contact support.')
            
            return redirect('login')
    else:
        form = SignupForm()
    return render(request, 'core/signup.html', {'form': form})

def activate(request, uidb64, token):
    try:
        uid = force_str(urlsafe_base64_decode(uidb64))
        user = User.objects.get(pk=uid)
    except(TypeError, ValueError, OverflowError, User.DoesNotExist):
        user = None
    if user is not None and account_activation_token.check_token(user, token):
        user.is_active = True
        user.save()
        login(request, user)
        messages.success(request, 'Thank you for your email confirmation. Now you can enjoy our services.')
        return redirect('dashboard')
    else:
        messages.error(request, 'Activation link is invalid!')
        return redirect('home')

@login_required
def dashboard(request):
    # Ensure profile exists (though signal should handle it)
    profile, created = Profile.objects.get_or_create(user=request.user)
    return render(request, 'core/dashboard.html', {'profile': profile})

def logout_view(request):
    logout(request)
    return redirect('home')