import requests
import stripe
from django.conf import settings
from django.contrib.auth.decorators import login_required
from django.core.mail import mail_admins
from django.core.mail import send_mail
from django.http import HttpResponse
from django.http import HttpResponseBadRequest
from django.shortcuts import get_object_or_404
from django.shortcuts import redirect
from django.shortcuts import render
from django.urls import reverse
from django.urls import reverse_lazy
from django.views import View
from django.views.decorators.csrf import csrf_exempt
from django.views.generic import DeleteView
from django.views.generic import TemplateView
from django_ratelimit.decorators import ratelimit

from alphabetlearning.payments.models import EmailSignup
from alphabetlearning.payments.models import EmailVerification
from alphabetlearning.resources.models import Resource
from alphabetlearning.users.models import User

from .forms import EmailVerificationForm
from .models import CartItem
from .models import Price
from .models import ShoppingCart

# TODO get the cart integrated with Stripe
# Steps to convert our Cart into something that can be used with Stripe:
#
#    - Fix the total in the cart
#    - X Sort out the webhook
#    - Associate the purchases with the users profile page
#    - We need a profile page!
#        - Link in navbar (when logged in)
#    - Fix the email and make it nice
#    - Associate each of our resources with a Product item
#        - this should be done in the create resource page
#        - or we can do it manually for the time being
#    - X Check that we can add resources to the cart
#    - X When the user hits the cart page, each associated product is pulled from the database
#    - X prices are extracted from the products accordingly
#    - X use the form from the landingpage.html as the checkout button to call the create-checkout-session
#    - Add delete buttons the checkout page, etc


stripe.api_key = settings.STRIPE_SECRET_KEY


class SuccessEmailSignupView(TemplateView):
    template_name = "payments/success_email_signup.html"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["email"] = self.request.POST.get("email")
        return context


@ratelimit(key="ip", rate="2/m", block=True)
def email_signup_verification(request):
    if request.method == "POST":
        form = EmailVerificationForm(request.POST)
        if form.is_valid():
            # Create pending verification
            pending_verification = EmailVerification.objects.create(
                email=form.cleaned_data.get("email"),
            )
            # Generate verification URL
            verification_url: str = request.build_absolute_uri(
                reverse(
                    "payments:verify_email", args=[str(pending_verification.verification_token)]
                )
            )
            # email = process_verification_emails(
            #     email=form.cleaned_data.get("email"),
            #     verification_url=verification_url,
            # )
            email = send_mailgun_verification(form.cleaned_data.get("email"), verification_url)
            return render(request, "payments/verification_sent.html", {"email": email})
        else:
            # email = process_verification_emails(email=request.POST.get("email"), warn=True)
            email = send_mailgun_verification(email=request.POST.get("email"), warn=True)
            return render(request, "payments/verification_sent.html", {"email": email})
    else:
        form = EmailVerificationForm()
    return render(request, "pages/home.html", {"form": form})  # Adjust as necessary


def send_mailgun_verification(
    email: str,
    verification_url: str = None,
    warn=False,
):
    if warn:
        warning_message = """
        You are already subscribed to our list - no further action is required.
        """
        requests.post(
            f"{settings.MAILGUN_API_URL}/{settings.MAILGUN_SENDER_DOMAIN}/messages",
            auth=("api", settings.MAILGUN_API_KEY),
            data={
                "from": f"No reply - Alphabet Learning <noreply@{settings.MAILGUN_SENDER_DOMAIN}>",
                "to": [
                    email,
                ],
                "subject": "Alphabet Learning - Email Verification",
                "text": f"Thanks, {email} for signing up.\n\n{warning_message}\n\nBest regards,\n\nThe Alphabet Learning Team",
            },
        )
    else:
        warning_message = f"""
        Please click the following link to verify your email address within 24 hours:
        {verification_url}
        If you didn't request this, please ignore this email.
        """
        requests.post(
            f"{settings.MAILGUN_API_URL}/{settings.MAILGUN_SENDER_DOMAIN}/messages",
            auth=("api", settings.MAILGUN_API_KEY),
            data={
                "from": f"No reply - Alphabet Learning <noreply@{settings.MAILGUN_SENDER_DOMAIN}>",
                "to": [
                    email,
                ],
                "subject": "Alphabet Learning - Email Verification",
                "text": f"Thanks, {email} for signing up.\n\n{warning_message}\n\nBest regards,\n\nThe Alphabet Learning Team",
            },
        )
    return email


def process_verification_emails(
    email: str,
    verification_url: str = None,
    warn=False,
):
    if warn is False:
        html_warning_message = f"""
        <p>Please click the following link to verify your email address within 24 hours:</p>
        <p><a href="{verification_url}">{verification_url}</a></p>
        <p>If you didn't request this, please ignore this email.</p>
        """
        warning_message = f"""
        Please click the following link to verify your email address within 24 hours:
        {verification_url}
        If you didn't request this, please ignore this email.
        """
        admin_warn = "They are not already subscribed."
    else:
        html_warning_message = """
        <p>You are already subscribed to our list - no further action is required.</p>
        """
        warning_message = """
        You are already subscribed to our list - no further action is required.
        """
        admin_warn = "They have already subscribed so have been told of this fact in their verification email. No further action required."

    # Send verification email
    subject = "Alphabet Learning - Email Verification"
    html_message = f"""
            <html>
            <body>
                <p>Hi!</p>
                <p>You recently requested to sign up to the Alphabet Learning contact list.</p>
                {html_warning_message}
                <p>Best regards,</p>
                <p>The Alphabet Learning Team</p>
            </body>
            </html>
            """
    message = f""" 
            Hi!,

            You recently requested to sign up to the Alphabet Learning contact list.
            
            {warning_message}

            Best regards,
            The Alphabet Learning Team
            """
    send_mail(
        subject,
        message,
        settings.DEFAULT_FROM_EMAIL,
        [email],
        fail_silently=False,
        html_message=html_message,
    )
    admin_message = f"""
            Joanna/Matthew,
            
            {email} has just signed up to the Alphabet Learning contact list. They are awaiting verification.
            
            {admin_warn}
            
            I will email again if they follow through with the verification.
            
            Best regards,
            The Alphabet Learning Server
            """
    mail_admins(subject, admin_message, fail_silently=False)
    return email


def verify_email(request, token):
    try:
        pending = EmailVerification.objects.get(verification_token=token, is_verified=False)

        if pending.is_expired:
            return render(request, "payments/verification_failed.html")

        # Create the subscriber
        EmailSignup.objects.create(
            email=pending.email,
        )

        # Mark as verified
        pending.is_verified = True
        pending.save()

        mail_admins(
            subject=f"{pending.email} has just signed up to the Alphabet Learning contact list.",
            message=f"{pending.email} has just signed up to the Alphabet Learning contact list. Their verification was successful.\n\n\n"
            f"Best regards,\n\nThe Alphabet Learning Server",
            fail_silently=False,
        )

        return render(request, "payments/success_email_signup.html")

    except EmailVerification.DoesNotExist:
        return render(request, "payments/verification_failed.html")


def create_line_items(resources):
    price_objs = [r.price_obj.first() for r in resources]
    stripe_price_ids = [p.stripe_price_id for p in price_objs]
    return [{"quantity": 1, "price": s} for s in stripe_price_ids]
    pass


class CreateCheckoutSessionView(View):
    def post(self, request, *args, **kwargs):
        # price = Price.objects.get(id=self.kwargs["pk"])
        cart = ShoppingCart.objects.get(id=self.kwargs["pk"])
        resources = [i.resource for i in cart.items.all()]
        total = sum([r.price_obj.first().price for r in resources])
        domain = "http://localhost:8000"
        checkout_session = stripe.checkout.Session.create(
            payment_method_types=["card"],
            customer_email=request.user.email,
            line_items=create_line_items(resources),
            mode="payment",
            success_url=domain + "/payments/success/",
            cancel_url=domain + "/payments/cancel/",
        )
        return redirect(checkout_session.url, code=303)


class SuccessView(TemplateView):
    template_name = "payments/success.html"


class CancelView(TemplateView):
    template_name = "payments/cancel.html"


class ProductLandingPageView(TemplateView):
    template_name = "payments/landingpage.html"

    def get_context_data(self, **kwargs):
        resource = Resource.objects.get(id=91)
        prices = Price.objects.filter(resource=resource)
        context = super(ProductLandingPageView, self).get_context_data(**kwargs)
        context.update({"resource": resource, "prices": prices})
        return context


@login_required
def add_to_cart(request, resource_id):
    resource = get_object_or_404(Resource, id=resource_id)
    if not resource.price_obj.first():
        return HttpResponseBadRequest(
            "There is no price assigned to this resource. Please contact Alphabet Learning Support."
        )
    cart, created = ShoppingCart.objects.get_or_create(user=request.user)
    cart_item, created = CartItem.objects.get_or_create(cart=cart, resource=resource)
    # cart_item.quantity += 1
    cart_item.save()
    return redirect("payments:cart_detail")


@login_required
def cart_detail(request):
    cart, created = ShoppingCart.objects.get_or_create(user=request.user)
    resources = [i.resource for i in cart.items.all()]
    total = sum([r.price_obj.first().price for r in resources]) / 1000
    context = {"cart": cart, "resources": resources, "total": total}
    return render(request, "payments/cart_detail.html", context)


# def cart_detail(request):
#     cart, created = ShoppingCart.objects.get_or_create(user=request.user)
#     return render(request, "payments/cart_detail.html", {"cart": cart})


@login_required
def checkout(request):
    cart = ShoppingCart.objects.get(user=request.user)
    total = sum(item.get_total_price() for item in cart.items.all())

    if request.method == "POST":
        # Create Stripe PaymentIntent
        intent = stripe.PaymentIntent.create(
            amount=int(total * 100),  # Stripe amount is in cents
            currency="usd",
            automatic_payment_methods={"enabled": True},
        )

        # Redirect to Stripe checkout or handle payment confirmation
        return render(request, "cart/checkout_success.html")

    return render(request, "cart/checkout.html", {"cart": cart, "total": total})


@csrf_exempt
def stripe_webhook(request):
    payload = request.body
    sig_header = request.META["HTTP_STRIPE_SIGNATURE"]
    event = None

    # verify that the request came from STRIPE
    try:
        event = stripe.Webhook.construct_event(payload, sig_header, settings.STRIPE_WEBHOOK_SECRET)
    except ValueError as e:
        return HttpResponse(status=400)
    except stripe.error.SignatureVerificationError as e:
        return HttpResponse(status=400)

    if event["type"] == "checkout.session.completed":
        session = event["data"]["object"]
        customer_email = session["customer_details"]["email"]
        payment_intent = session["payment_intent"]

        # TODO Add the items to the users profile page
        # This should be done before deleting the cart otherwise we have no record of what they bought

        # TODO clear their shopping cart - we need to obtain their user ID
        user = User.objects.get(email=customer_email)
        ShoppingCart.objects.get(user=user).delete()

        # TODO add the transaction to our local history? Or just use Stripe?

        # TODO send an email to the customer
        send_mail(
            "Thank you for your purchase",
            "You have bought something nice - enjoy it",
            settings.DEFAULT_FROM_EMAIL,
            [customer_email],
            fail_silently=False,
        )
    return HttpResponse(status=200)


class DeleteCartItem(DeleteView):
    model = CartItem
    success_url = reverse_lazy("payments:cart_detail")

    # delete the cart item if there is more than one
    # delete the item and the cart itself if it is the last thing in the cart
    def post(self, request, *args, **kwargs):
        cart_items = request.user.shoppingcart.items.all()
        if len(cart_items) > 1:
            return self.delete(request, *args, **kwargs)
        else:
            request.user.shoppingcart.delete()
            return redirect("resources:resource_list")


def privacy_policy(request):
    return render(request, "pages/privacy_policy.html")