Custom filter for filter_horizontal admin in django

I have the following models where a deck have a many to many relationship with problems and problems can have tags

from django.utils import timezone
from django.db import models
from taggit.models import TaggedItemBase
from taggit.managers import TaggableManager

# Create your models here.

class TaggedProblem(TaggedItemBase):
    content_object = models.ForeignKey('Problem', on_delete=models.CASCADE)

class Problem(models.Model):
    title = models.CharField(max_length=200)
    body = models.CharField(max_length=10000)
    pub_date = models.DateTimeField("date published", default=timezone.now())
    tags = TaggableManager(through=TaggedProblem)

    class Meta:
        verbose_name = "problem"
        verbose_name_plural = "problems"

    def __str__(self):
        return self.title

class Deck(models.Model):
    name = models.CharField(max_length=200)
    problems = models.ManyToManyField(Problem) 
    def __str__(self):
        return self.name

then for the admin i have the following

from django.contrib import admin

# Register your models here.

from .models import Problem,Deck
  
class DeckAdmin(admin.ModelAdmin):
    filter_horizontal = ('problems',)

admin.site.register(Deck, DeckAdmin)
admin.site.register(Problem)

and the admin looks like this enter image description here

well what i want to do is to have a custom filter to filter the available problems, the filter must be an interface where i can include and exclude tags associated with the problems, so i want to replace the filter search box with something like this

enter image description here

so i can filter the problems by tags and then add then to the deck, how can i achieve that functionality?, i am new to django and have no idea how to proceed

I think the key is to create a custom ModelForm that dynamically filters the problems queryset based on tag criteria before the horizontal filter widget is rendered.

Something like this

# admin.py
from django import forms
from django.contrib import admin
from .models import Problem, Deck

class DeckAdminForm(forms.ModelForm):
    include_tags = forms.CharField(
        required=False,
        help_text="Enter tags to include (comma-separated)"
    )
    exclude_tags = forms.CharField(
        required=False, 
        help_text="Enter tags to exclude (comma-separated)"
    )
    
    class Meta:
        model = Deck
        fields = '__all__'
    
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        
        # Get filter parameters from form data
        include_tags = self.data.get('include_tags', '') if self.data else ''
        exclude_tags = self.data.get('exclude_tags', '') if self.data else ''
        
        if include_tags or exclude_tags:
            # Start with all problems
            queryset = Problem.objects.all()
            
            # Apply include filter
            if include_tags:
                include_list = [tag.strip() for tag in include_tags.split(',') if tag.strip()]
                queryset = queryset.filter(tags__name__in=include_list).distinct()
            
            # Apply exclude filter  
            if exclude_tags:
                exclude_list = [tag.strip() for tag in exclude_tags.split(',') if tag.strip()]
                queryset = queryset.exclude(tags__name__in=exclude_list).distinct()
            
            # Update the problems field queryset
            self.fields['problems'].queryset = queryset

class DeckAdmin(admin.ModelAdmin):
    form = DeckAdminForm
    filter_horizontal = ('problems',)

admin.site.register(Deck, DeckAdmin)
admin.site.register(Problem)

Also (alternative solution), you can create a custom admin form with a specialized widget that combines tag filtering with the horizontal filter interface but it's a bit complicated (js, css..)

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