# Site-Wide Search System Architecture

## 1. Architectural Overview
- **Filter-First Approach**: Utilizes django-filter for robust filtering capabilities
- **Modular Design**:
  ```python
  # filters.py
  class ParkFilter(django_filters.FilterSet):
      search = django_filters.CharFilter(method='filter_search')
      
      class Meta:
          model = Park
          fields = {
              'state': ['exact', 'in'],
              'rating': ['gte', 'lte'],
          }

      def filter_search(self, queryset, name, value):
          return queryset.filter(
              Q(name__icontains=value) | 
              Q(description__icontains=value)
          )
  ```

## 2. Enhanced Backend Components

### Search Endpoint (`/search/`)
```python
# views.py
class AdaptiveSearchView(TemplateView):
    template_name = "search/results.html"
    
    def get_queryset(self):
        return Park.objects.all()

    def get_filterset(self):
        return ParkFilter(self.request.GET, queryset=self.get_queryset())

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        filterset = self.get_filterset()
        context['results'] = filterset.qs
        context['filters'] = filterset.form
        return context
```

## 3. Plugin Integration

### Recommended django-filter Extensions
```python
# settings.py
INSTALLED_APPS += [
    'django_filters',
    'django_filters_addons',  # For custom widgets
    'rangefilter',            # For date/number ranges
]

# filters.py
class EnhancedParkFilter(ParkFilter):
    rating_range = django_filters.RangeFilter(field_name='rating')
    features = django_filters.MultipleChoiceFilter(
        field_name='features__slug',
        widget=HorizontalCheckboxSelectMultiple,
        lookup_expr='contains'
    )
    
    class Meta(ParkFilter.Meta):
        fields = ParkFilter.Meta.fields + ['rating_range', 'features']
```

## 4. Frontend Filter Rendering
```html
<!-- templates/search/filters.html -->
<form hx-get="/search/" hx-target="#search-results" hx-swap="outerHTML">
    {{ filters.form.as_p }}
    <button type="submit">Apply Filters</button>
</form>

<!-- Dynamic filter updates -->
<div hx-trigger="filter-update from:body" 
     hx-get="/search/filters/" 
     hx-swap="innerHTML">
</div>
```

## 5. Benefits of django-filter Integration
- Built-in validation for filter parameters
- Automatic form generation
- Complex lookup expressions
- Reusable filter components
- Plugin ecosystem support

## 6. Security Considerations
- Input sanitization using django's built-in escaping
- Query parameter whitelisting via FilterSet definitions
- Rate limiting on autocomplete endpoint (using django-ratelimit)
- Permission-aware queryset filtering

## 7. Performance Optimization
- Select related/prefetch_related in FilterSet querysets
- Caching filter configurations
- Indexing recommendations for filtered fields
- Pagination integration with django-filter

## 8. Testing Strategy
- FilterSet validation tests
- HTMX interaction tests
- Cross-browser filter UI tests
- Performance load testing

## 9. Style Integration
- Custom filter form templates matching Tailwind design
- Responsive filter controls grid
- Accessible form labels and error messages
- Dark mode support

## 10. Expansion Framework
- Registry pattern for adding new FilterSets
- Dynamic filter discovery system
- Plugin configuration templates
- Analytics integration points