import logging
from urllib.parse import urlencode

from django.conf import settings
from django.core.mail import send_mail
from django.db.models import BooleanField, Case, Value, When
from django.shortcuts import redirect, render
from django.urls import reverse
from django.contrib import messages

from favorites.services import get_user_favorite_item_ids
from home.forms import FaqQuestionForm
from items.models import Category, Item
from orders.services import get_user_cart_item_ids


logger = logging.getLogger(__name__)

CONTACT_ADDRESS = "Беларусь, г. Минск, ул. Тимирязева, д. 123, к.1, пав. 59"
CONTACT_EMAIL = "info@santehray.by"
CONTACT_PHONE_PRIMARY = "+375 (29) 688-18-19"
CONTACT_PHONE_PRIMARY_URL = "+375296881819"
CONTACT_PHONE_SECONDARY = "+375 (33) 337-67-81"
CONTACT_PHONE_SECONDARY_URL = "+375333376781"
CONTACT_HOURS_WEEKDAYS = "Пн-Пт: 9.00 - 21.00"
CONTACT_HOURS_WEEKENDS = "Сб-Вс: 10.00 - 18.00"
CONTACT_MAP_CENTER = {"lat": "53.9334960", "lon": "27.4551021", "zoom": 15}
CONTACT_MAP_EXTERNAL_URL = (
    "https://www.openstreetmap.org/?mlat=53.9334960&mlon=27.4551021#map=15/53.9334960/27.4551021"
)


def build_home_category_url(category_slug: str, **query_params: str) -> str:
    normalized_slug = (category_slug or "").strip().lower()
    base_url = "/catalog/"
    if normalized_slug and Category.objects.filter(slug=normalized_slug).exists():
        base_url = f"/catalog/{normalized_slug}/"

    clean_query_params = {key: value for key, value in query_params.items() if value}
    if not clean_query_params:
        return base_url

    return f"{base_url}?{urlencode(clean_query_params)}"


def index(request):
    form = FaqQuestionForm(request.POST or None)

    if request.method == "POST" and form.is_valid():
        subject = f"Новый вопрос с сайта {settings.SITE_NAME}"
        message = "\n".join(
            [
                f"Имя: {form.cleaned_data['name']}",
                f"Телефон: {form.cleaned_data['phone']}",
                f"Вопрос: {form.cleaned_data['question']}",
                "",
                f"Страница: {request.build_absolute_uri('/')}",
            ]
        )

        try:
            send_mail(
                subject=subject,
                message=message,
                from_email=settings.DEFAULT_FROM_EMAIL,
                recipient_list=[settings.ADMINISTRATOR_EMAIL],
                fail_silently=False,
            )
        except Exception:
            logger.exception("Failed to send FAQ question email")
            form.add_error(None, "Не удалось отправить вопрос. Попробуйте позже.")
        else:
            messages.success(request, "Спасибо. Ваш вопрос отправлен, мы свяжемся с вами в ближайшее время.")
            return redirect(f"{reverse('home')}#faq-section")

    home_products = (
        Item.objects.filter(is_available=True)
        .select_related("category", "subcategory")
        .prefetch_related("images")
        .annotate(
            discount_sort=Case(
                When(discount_price__isnull=False, then=Value(True)),
                default=Value(False),
                output_field=BooleanField(),
            )
        )
        .order_by("-is_new", "-discount_sort", "-created_at")[:6]
    )

    return render(request=request, template_name='home/index.html', context={
        "faq_form": form,
        "home_products": home_products,
        "home_advantages_left_url": build_home_category_url(
            settings.HOME_ADVANTAGES_LEFT_CATEGORY_SLUG,
            new="1" if settings.HOME_ADVANTAGES_LEFT_NEW_FILTER else "",
        ),
        "home_advantages_right_url": build_home_category_url(
            settings.HOME_ADVANTAGES_RIGHT_CATEGORY_SLUG,
            sale="1" if settings.HOME_ADVANTAGES_RIGHT_SALE_FILTER else "",
        ),
        "favorite_item_ids": get_user_favorite_item_ids(request.user),
        "cart_item_ids": get_user_cart_item_ids(request.user),
    })


def services(request):
    return render(request=request, template_name='home/services.html', context={})


def shipping(request):
    return render(request=request, template_name='home/shipping.html', context={})


def warranty(request):
    return render(request=request, template_name='home/warranty.html', context={})


def contacts(request):
    context = {
        "contact_address": CONTACT_ADDRESS,
        "contact_email": CONTACT_EMAIL,
        "contact_phone_primary": CONTACT_PHONE_PRIMARY,
        "contact_phone_primary_url": CONTACT_PHONE_PRIMARY_URL,
        "contact_phone_secondary": CONTACT_PHONE_SECONDARY,
        "contact_phone_secondary_url": CONTACT_PHONE_SECONDARY_URL,
        "contact_hours_weekdays": CONTACT_HOURS_WEEKDAYS,
        "contact_hours_weekends": CONTACT_HOURS_WEEKENDS,
        "map_lat": CONTACT_MAP_CENTER["lat"],
        "map_lon": CONTACT_MAP_CENTER["lon"],
        "map_zoom": CONTACT_MAP_CENTER["zoom"],
        "map_external_url": CONTACT_MAP_EXTERNAL_URL,
    }
    return render(request=request, template_name='home/contacts.html', context=context)