def validation_hashtag(value):
    if not re.match(r"^[0-9a-zA-Z_]+$", value):
        # ^: 시작 / $ : 특정 패턴 끝
        raise ValidationError


class HashTag(models.Model):
    name = models.CharField(max_length=50, unique=True, validators=[validation_hashtag])

    def __str__(self):
        return f"#{self.name}"

class Products(models.Model):
    ...
    hashtags = models.ManyToManyField(HashTag, related_name='products', blank=True)
    ...

class ProductsForm(forms.ModelForm):
    hashtags_str = forms.CharField(required=False)

    def __init__(self, *args, **kwargs):
        self.user = kwargs.pop("user", None)
        super().__init__(*args, **kwargs)

    class Meta:
        model = Products
        fields = "__all__"
        exclude = ("author", "like_user", "views", "hashtags")

    def save(self, commit=True):
        product = super().save(commit=False)

        # 사용자가 제공된 경우, 'user' 값을 'product'의 'user'와 'author' 필드에 할당
        if self.user:
            product.user = self.user
            product.author = self.user

        if commit:
            product.save()

        hashtags_input = self.cleaned_data.get("hashtags_str", "")
        hashtag_list = [h for h in hashtags_input.replace(",", " ").split() if h]
        new_hashtags = []
        for ht in hashtag_list:
            ht_obj, created = HashTag.objects.get_or_create(name=ht)
            new_hashtags.append(ht_obj)
        product.hashtags.set(new_hashtags)

        if not commit:
            product.save()

        return product

from django.views.generic import FormView
from django.db.models import Q

class SearchFormView(FormView):
    form_class = SearchForm
    template_name = "products/search.html"

    def form_valid(self, form):
        searchWord = form.cleaned_data["search_word"]
        products_list = Products.objects.filter(
            Q(title__icontains=searchWord)
            | Q(product_name__icontains=searchWord)
            | Q(content__icontains=searchWord)
        ).distinct()

        context = {
            "form": form,
            "searchWord": searchWord,
            "products_list": products_list,
        }

        return render(self.request, "products/search.html", context)

from django.db.models import Count

def products(request):
    sort = request.GET.get('sort', 'date')  # 기본값은 날짜순으로 설정
    if sort == 'likes':
        products = Products.objects.annotate(like_count=Count('like_user')).order_by('-like_count', '-created_at')  # 좋아요 순으로 정렬
    elif sort == 'comments':
        products = Products.objects.annotate(comment_count=Count('comments')).order_by('-comment_count', '-created_at')  # 댓글 순으로 정렬
    else:  
        products = Products.objects.all().order_by('-created_at')  # 날짜 순으로 정렬

    context = {
        'products': products,
    }
    return render(request, "products/products.html", context)