# Parks and Rides API 501 Error Fix - Frontend Integration Prompt

## Project Context
ThrillWiki is a comprehensive theme park and ride database with Django REST API backend. The parks and rides listing endpoints were returning 501 errors due to incorrect model imports, preventing frontend integration.

## High-Level Objectives
- Fix 501 errors in both `/api/v1/parks/` and `/api/v1/rides/` endpoints
- Ensure proper model imports and database query functionality
- Maintain existing API contract and response formats
- Verify all filtering and search functionality works correctly

## Technical Implementation Details

### Root Cause Analysis
Both API endpoints were attempting to import the Company model from a non-existent `apps.companies.models` module. The Company model is actually located in `apps.parks.models`.

### Backend Changes Applied

#### Parks API (`backend/apps/api/v1/parks/park_views.py`)
- **Import Fix**: Changed from `from apps.companies.models import Company` to `from apps.parks.models import Park, Company`
- **Annotation Conflicts**: Resolved database annotation conflicts by using calculated field names to avoid conflicts with existing model fields
- **Query Optimization**: Maintained existing select_related and prefetch_related optimizations

#### Rides API (`backend/apps/api/v1/rides/views.py`)
- **Import Fix**: Simplified imports to use single Company model from parks app
- **Variable References**: Updated all Company references to use correct import
- **Maintained Functionality**: All filtering, search, and pagination features preserved

### API Endpoints Now Functional

#### Parks API Endpoints
- `GET /api/v1/parks/` - List parks with comprehensive filtering and pagination
- `GET /api/v1/parks/filter-options/` - Get filter metadata for frontend forms
- `GET /api/v1/parks/search/companies/?q={query}` - Company autocomplete search
- `GET /api/v1/parks/search-suggestions/?q={query}` - Park name suggestions
- `GET /api/v1/parks/{id}/` - Individual park details
- `PATCH /api/v1/parks/{id}/image-settings/` - Set banner/card images

#### Rides API Endpoints
- `GET /api/v1/rides/` - List rides with comprehensive filtering and pagination
- `GET /api/v1/rides/filter-options/` - Get filter metadata for frontend forms
- `GET /api/v1/rides/search/companies/?q={query}` - Company autocomplete search
- `GET /api/v1/rides/search/ride-models/?q={query}` - Ride model autocomplete
- `GET /api/v1/rides/search-suggestions/?q={query}` - Ride name suggestions
- `GET /api/v1/rides/{id}/` - Individual ride details
- `PATCH /api/v1/rides/{id}/image-settings/` - Set banner/card images

### Mandatory API Rules Compliance
- **Trailing Forward Slashes**: All API endpoints include mandatory trailing forward slashes
- **HTTP Methods**: Proper GET/POST/PATCH/DELETE method usage
- **Authentication**: Public endpoints use AllowAny permissions
- **Error Handling**: Proper 404/400/500 error responses with detailed messages
- **Pagination**: Standard pagination with count, next, previous fields

### Response Format Examples

#### Parks List Response
```json
{
    "count": 7,
    "next": "http://localhost:8000/api/v1/parks/?page=2&page_size=2",
    "previous": null,
    "results": [
        {
            "id": 99,
            "name": "Cedar Point",
            "slug": "cedar-point",
            "status": "OPERATING",
            "description": "Known as the \"Roller Coaster Capital of the World\".",
            "average_rating": null,
            "coaster_count": 4,
            "ride_count": 4,
            "location": {
                "latitude": null,
                "longitude": null,
                "city": null,
                "state": null,
                "country": null,
                "formatted_address": ""
            },
            "operator": {
                "id": 114,
                "name": "Cedar Fair Entertainment Company",
                "slug": "cedar-fair-entertainment-company",
                "roles": ["OPERATOR"],
                "url": ""
            },
            "url": "http://www.thrillwiki.com/parks/cedar-point/",
            "created_at": "2025-08-22T15:33:27.302477-04:00",
            "updated_at": "2025-08-28T19:13:11.773038-04:00"
        }
    ]
}
```

#### Rides List Response
```json
{
    "count": 10,
    "next": "http://localhost:8000/api/v1/rides/?page=2&page_size=2",
    "previous": null,
    "results": [
        {
            "id": 134,
            "name": "Big Thunder Mountain Railroad",
            "slug": "big-thunder-mountain-railroad",
            "category": "RC",
            "status": "OPERATING",
            "description": "Mine train roller coaster themed as a runaway mining train.",
            "park": {
                "id": 97,
                "name": "Magic Kingdom",
                "slug": "magic-kingdom"
            },
            "average_rating": null,
            "capacity_per_hour": null,
            "opening_date": "1980-11-15",
            "closing_date": null,
            "url": "http://www.thrillwiki.com/parks/magic-kingdom/rides/big-thunder-mountain-railroad/",
            "created_at": "2025-08-22T15:33:27.326714-04:00",
            "updated_at": "2025-08-28T19:13:11.752830-04:00"
        }
    ]
}
```

### Filter Options Response Structure
Both parks and rides filter options endpoints return comprehensive metadata including:
- **Categories**: Available ride/park categories with labels
- **Statuses**: Operational status options
- **Ordering Options**: Sort field options with human-readable labels
- **Filter Ranges**: Min/max/step values for numeric filters
- **Boolean Filters**: Toggle filter definitions

### Frontend Integration Requirements

#### TypeScript Integration
- All endpoints return properly typed responses
- Company model unified across parks and rides domains
- Consistent error handling patterns
- Proper pagination interface implementation

#### State Management Patterns
- Handle loading states during API calls
- Implement proper error boundaries for 404/500 responses
- Cache filter options to reduce API calls
- Debounce search/autocomplete queries

#### User Experience Recommendations
- Show loading indicators during data fetching
- Implement infinite scroll or pagination controls
- Provide clear error messages for failed requests
- Use autocomplete for company and ride model searches

### Performance Optimization Strategies
- **Database Queries**: All endpoints use optimized select_related and prefetch_related
- **Caching**: Filter options can be cached client-side
- **Pagination**: Use appropriate page sizes (default 20, max 1000)
- **Search Debouncing**: Implement 300ms debounce for search queries

### Testing Considerations
- Verify all endpoints return 200 status codes
- Test pagination with various page sizes
- Validate filter combinations work correctly
- Ensure search functionality returns relevant results
- Test error handling for invalid parameters

### Backend Compatibility Notes
- **Fully Supported**: All documented endpoints are fully functional
- **Real Database Queries**: All responses use actual database data, no mock responses
- **Consistent Response Format**: All endpoints follow DRF pagination standards
- **Error Handling**: Proper HTTP status codes and error messages

### Documentation Maintenance
This fix resolves the 501 errors and restores full functionality to both parks and rides API endpoints. All existing frontend integration patterns should continue to work without modification.

### Version Information
- **Fix Applied**: 2025-08-31
- **Django Version**: Compatible with current project setup
- **API Version**: v1 (stable)
- **Breaking Changes**: None - maintains existing API contract
