# AGENTS.md - AI Coding Agent Guidelines

This document provides guidelines for AI coding agents working in the labhelper repository.

## Project Overview

- **Type**: Django web application
- **Python**: 3.13.7
- **Django**: 5.2.9
- **Database**: SQLite (development)
- **Virtual Environment**: `.venv/`

## Build/Run Commands

### Development Server

```bash
python manage.py runserver              # Start dev server on port 8000
python manage.py runserver 0.0.0.0:8000 # Bind to all interfaces
```

### Database Operations

```bash
python manage.py makemigrations         # Create migration files
python manage.py makemigrations boxes   # Create migrations for specific app
python manage.py migrate                # Apply all migrations
python manage.py showmigrations         # List migration status
```

### Testing

```bash
# Run all tests
python manage.py test

# Run tests for a specific app
python manage.py test boxes

# Run a specific test class
python manage.py test boxes.tests.TestClassName

# Run a single test method
python manage.py test boxes.tests.TestClassName.test_method_name

# Run tests with verbosity
python manage.py test -v 2

# Run tests with coverage
coverage run manage.py test
coverage report
coverage html  # Generate HTML report
```

### Django Shell

```bash
python manage.py shell                  # Interactive Django shell
python manage.py createsuperuser        # Create admin user
python manage.py collectstatic          # Collect static files
```

### Production

```bash
gunicorn labhelper.wsgi:application     # Run with Gunicorn
```

## Code Style Guidelines

### Python Style

- Follow PEP 8 conventions
- Use 4-space indentation (no tabs)
- Maximum line length: 79 characters (PEP 8 standard)
- Use single quotes for strings: `'string'`
- Use double quotes for docstrings: `"""Docstring."""`

### Import Order

Organize imports in this order, with blank lines between groups:

```python
# 1. Standard library imports
import os
import sys
from pathlib import Path

# 2. Django imports
from django.db import models
from django.contrib import admin
from django.shortcuts import render, redirect
from django.http import HttpResponse, JsonResponse

# 3. Third-party imports
import requests
from markdown import markdown

# 4. Local application imports
from .models import MyModel
from .forms import MyForm
```

### Naming Conventions

| Type | Convention | Example |
|------|------------|---------|
| Modules | lowercase_with_underscores | `user_profile.py` |
| Classes | PascalCase | `UserProfile` |
| Functions | lowercase_with_underscores | `get_user_data()` |
| Constants | UPPERCASE_WITH_UNDERSCORES | `MAX_CONNECTIONS` |
| Variables | lowercase_with_underscores | `user_count` |
| Django Models | PascalCase (singular) | `Box`, `UserProfile` |
| Django Apps | lowercase (short) | `boxes`, `users` |

### Django-Specific Conventions

**Models:**
```python
from django.db import models

class Box(models.Model):
    """A storage box in the lab."""
    
    name = models.CharField(max_length=255)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        verbose_name_plural = 'boxes'
        ordering = ['-created_at']

    def __str__(self):
        return self.name
```

**Views:**
```python
from django.shortcuts import render, get_object_or_404
from django.http import Http404

def box_detail(request, box_id):
    """Display details for a specific box."""
    box = get_object_or_404(Box, pk=box_id)
    return render(request, 'boxes/detail.html', {'box': box})
```

### Error Handling

```python
# Use specific exceptions
try:
    result = some_operation()
except SpecificError as exc:
    raise CustomError('Descriptive message') from exc

# Django: Use get_object_or_404 for model lookups
box = get_object_or_404(Box, pk=box_id)

# Log errors appropriately
import logging
logger = logging.getLogger(__name__)
logger.error('Error message: %s', error_detail)
```

### Type Hints (Recommended)

```python
from typing import Optional
from django.http import HttpRequest, HttpResponse

def get_box(request: HttpRequest, box_id: int) -> HttpResponse:
    """Retrieve a box by ID."""
    ...
```

## Project Structure

```
labhelper/
├── manage.py               # Django CLI entry point
├── requirements.txt        # Python dependencies
├── labhelper/              # Project configuration
│   ├── settings.py         # Django settings
│   ├── urls.py             # Root URL routing
│   ├── wsgi.py             # WSGI application
│   └── asgi.py             # ASGI application
└── boxes/                  # Django app
    ├── admin.py            # Admin configuration
    ├── apps.py             # App configuration
    ├── models.py           # Data models
    ├── views.py            # View functions
    ├── tests.py            # Test cases
    ├── migrations/         # Database migrations
    └── templates/          # HTML templates
```

## Available Django Extensions

The project includes these pre-installed packages:

- **django-mptt**: Tree structures (categories, hierarchies)
- **django-mptt-admin**: Admin interface for MPTT models
- **django-admin-sortable2**: Drag-and-drop ordering in admin
- **django-nested-admin**: Nested inline forms in admin
- **django-nested-inline**: Additional nested inline support
- **django-revproxy**: Reverse proxy functionality

## Testing Guidelines

- Use `django.test.TestCase` for database tests
- Use `django.test.SimpleTestCase` for tests without database
- Name test files `test_*.py` or `*_tests.py`
- Name test methods `test_*`
- Use descriptive test method names

```python
from django.test import TestCase
from .models import Box

class BoxModelTests(TestCase):
    """Tests for the Box model."""

    def setUp(self):
        """Set up test fixtures."""
        self.box = Box.objects.create(name='Test Box')

    def test_box_str_returns_name(self):
        """Box __str__ should return the box name."""
        self.assertEqual(str(self.box), 'Test Box')
```

## Files to Never Commit

Per `.gitignore`:
- `__pycache__/`, `*.pyc` - Python bytecode
- `.venv/` - Virtual environment
- `.env` - Environment variables
- `data/db.sqlite3` - Database file
- `keys/` - Secret keys

## Common Pitfalls

1. **Always activate venv**: `source .venv/bin/activate`
2. **Run migrations after model changes**: `makemigrations` then `migrate`
3. **Add new apps to INSTALLED_APPS** in `settings.py`
4. **Use get_object_or_404** instead of bare `.get()` calls
5. **Never commit SECRET_KEY** - use environment variables in production

## Deployment Commands

### Prepare a Full Deployment

When instructed to "Prepare a full deployment", perform the following steps:

1. **Bump container versions**: In `argocd/deployment.yaml`, increment the version numbers by 0.001 for both containers:
   - `labhelper-data-loader` (initContainer)
   - `labhelper` (main container)

2. **Copy database**: Copy the current development database to the data-loader preload location:
   ```bash
   cp data/db.sqlite3 data-loader/preload.sqlite3
   ```

### Prepare a Partial Deployment

When instructed to "Prepare a partial deployment", perform the following step:

1. **Bump main container version only**: In `argocd/deployment.yaml`, increment the version number by 0.001 for the main container only:
   - `labhelper` (main container)

Do NOT bump the data-loader version or copy the database.