# Package Appointments Implementation Summary

## Overview

This document summarizes the implementation of the package-based appointment system with auto-scheduling functionality. The system allows users to differentiate between single sessions and packages, with support for multiple providers and automatic scheduling based on availability and preferred days.

## Implementation Date
November 11, 2025

## What Was Implemented

### 1. Package Models (`appointments/package_models.py`)

Created three new models to support package appointments:

#### **AppointmentPackage**
- Represents a package of multiple appointment sessions
- Fields:
  - `package_number`: Unique identifier (format: PKG-YYYYMMDD-NNNN)
  - `patient`, `clinic`: Core relationships
  - `service_type`: Type of service for all sessions
  - `total_sessions`: Number of sessions (2-100)
  - `session_duration`: Duration of each session in minutes
  - `status`: DRAFT, SCHEDULED, IN_PROGRESS, COMPLETED, CANCELLED
  - `preferred_days`: JSON list of preferred day numbers (0=Sunday, 6=Saturday)
  - `start_date`, `end_date`: Date range for scheduling
  - `use_multiple_providers`: Boolean flag for provider assignment strategy
  - `auto_schedule`: Boolean flag for automatic scheduling
  - `scheduling_completed`, `scheduling_errors`: Auto-scheduling tracking
- Properties:
  - `completed_sessions_count`, `scheduled_sessions_count`, `pending_sessions_count`
  - `progress_percentage`, `is_completed`, `can_cancel`
  - `get_preferred_days_display()`: Human-readable preferred days

#### **PackageSession**
- Represents an individual session within a package
- Fields:
  - `package`: Foreign key to AppointmentPackage
  - `appointment`: One-to-one link to Appointment (when scheduled)
  - `provider`: Assigned provider for this session
  - `session_number`: Order in package (1, 2, 3, ...)
  - `status`: PENDING, SCHEDULED, COMPLETED, CANCELLED, FAILED
  - `preferred_date`, `scheduled_date`, `scheduled_time`: Scheduling info
  - `scheduling_error`, `scheduling_attempts`: Error tracking
- Properties:
  - `is_scheduled`, `is_completed`, `can_reschedule`
  - `get_status_color()`: Bootstrap color class

#### **ProviderAssignment**
- Tracks provider assignments for package sessions
- Fields:
  - `package`: Foreign key to AppointmentPackage
  - `provider`: Assigned provider
  - `session_number`: Which session this provider is assigned to
  - `notes`: Additional notes

### 2. Auto-Scheduling Service (`appointments/package_scheduling_service.py`)

Created `PackageSchedulingService` class with the following methods:

#### **create_package_with_sessions()**
- Creates a new package with all sessions
- Handles provider assignments (single or multiple)
- Triggers auto-scheduling if enabled
- Returns package and list of errors

#### **auto_schedule_package()**
- Automatically schedules all pending sessions in a package
- Respects preferred days and date range
- Uses availability service to find open slots
- Returns list of scheduling errors

#### **_schedule_single_session()**
- Schedules one session within date range
- Checks provider availability
- Filters by preferred days
- Creates appointment when slot found
- Tries up to 90 days

#### **_create_appointment_for_session()**
- Creates an Appointment object for a scheduled session
- Generates unique appointment number
- Links appointment to package session

#### **reschedule_session()**
- Reschedules a specific session in a package
- Validates new slot availability
- Updates both appointment and session

#### **cancel_package()**
- Cancels entire package and all scheduled appointments
- Tracks cancellation reason and user
- Returns success status and message

#### **_generate_package_number()** & **_generate_appointment_number()**
- Generate unique identifiers with date-based format

#### **get_package_summary()**
- Returns comprehensive package status and session details
- Useful for API responses and reporting

### 3. Package Forms (`appointments/package_forms.py`)

Created comprehensive forms for package management:

#### **AppointmentTypeSelectionForm**
- Radio button selection between single session and package
- Used as first step in appointment creation

#### **PackageCreateForm**
- Complete form for creating a new package
- Fields:
  - Patient and clinic selection
  - Service type, total sessions, session duration
  - Start date, end date (optional)
  - Preferred days (multi-select checkboxes)
  - Provider assignment strategy (single vs multiple)
  - Single provider selection (when not using multiple)
  - Auto-schedule checkbox
  - Notes
- Validation:
  - Ensures provider is selected
  - Validates date range
  - Converts preferred days to integer list

#### **ProviderAssignmentForm**
- Dynamic form for assigning providers to individual sessions
- Creates one field per session
- Filters providers by clinic
- Returns provider assignments as dictionary

#### **PackageSessionRescheduleForm**
- Form for rescheduling a single session
- Fields: new date, new time, reason

#### **PackageCancelForm**
- Form for cancelling entire package
- Requires confirmation checkbox
- Shows warning about cancelling all appointments

#### **PackageSearchForm**
- Search and filter packages
- Fields: search query, clinic, status, date range

### 4. Model Updates

#### **appointments/models.py**
- Added import statement for package models at the top:
  ```python
  from .package_models import AppointmentPackage, PackageSession, ProviderAssignment
  ```

### 5. Admin Interface (`appointments/admin.py`)

Added admin classes for all package models:

#### **AppointmentPackageAdmin**
- List display: package number, patient, clinic, sessions, progress, status
- Filters: status, clinic, provider strategy, auto-schedule, date
- Inlines: ProviderAssignmentInline, PackageSessionInline
- Readonly fields: progress metrics, completion status
- Custom display: `progress_display()` shows percentage and count

#### **PackageSessionAdmin**
- List display: package, session number, provider, status, date/time
- Filters: status, clinic, date, provider
- Readonly fields: scheduling status properties
- Optimized queryset with select_related

#### **ProviderAssignmentAdmin**
- List display: package, session number, provider
- Filters: clinic, provider
- Simple interface for viewing assignments

## Key Features

### 1. **Differentiation Between Single Session and Package**
- Users can choose appointment type at creation
- Single sessions use existing workflow
- Packages use new multi-session workflow

### 2. **Multiple Provider Support**
- Option to use same provider for all sessions
- Option to assign different providers per session
- Provider assignments tracked in ProviderAssignment model

### 3. **Auto-Scheduling**
- Automatically finds available slots for all sessions
- Respects provider schedules and existing appointments
- Considers preferred days of the week
- Schedules sessions sequentially with at least 1 day gap
- Handles scheduling failures gracefully

### 4. **Preferred Days Selection**
- Users can select specific days of the week
- System only schedules on preferred days
- If no days selected, any day is acceptable

### 5. **Progress Tracking**
- Real-time progress percentage
- Counts: completed, scheduled, pending sessions
- Visual progress indicators in admin

### 6. **Error Handling**
- Tracks scheduling errors per session
- Stores error messages for troubleshooting
- Allows manual rescheduling of failed sessions

## Database Schema

### New Tables Created
1. `appointments_appointmentpackage` - Package master records
2. `appointments_packagesession` - Individual sessions in packages
3. `appointments_providerassignment` - Provider-to-session mappings
4. Historical tables for audit trail (via simple-history)

### Relationships
```
AppointmentPackage (1) -----> (N) PackageSession
AppointmentPackage (1) -----> (N) ProviderAssignment
PackageSession (1) -----> (1) Appointment
PackageSession (N) -----> (1) Provider
ProviderAssignment (N) -----> (1) Provider
```

## Next Steps

### 1. Create Database Migrations
```bash
python manage.py makemigrations appointments
python manage.py migrate
```

### 2. Update Appointment Creation View

Modify `appointments/views.py` to add package creation views:

```python
# Add these imports
from .package_forms import (
    AppointmentTypeSelectionForm,
    PackageCreateForm,
    ProviderAssignmentForm,
)
from .package_scheduling_service import PackageSchedulingService

# Add new views:
# - appointment_type_selection_view()
# - package_create_view()
# - provider_assignment_view()
# - package_detail_view()
# - package_list_view()
# - package_cancel_view()
# - session_reschedule_view()
```

### 3. Update URLs

Add package-related URLs to `appointments/urls.py`:

```python
# Package URLs
path('packages/', views.package_list_view, name='package_list'),
path('packages/create/', views.package_create_view, name='package_create'),
path('packages/<uuid:pk>/', views.package_detail_view, name='package_detail'),
path('packages/<uuid:pk>/cancel/', views.package_cancel_view, name='package_cancel'),
path('packages/sessions/<uuid:pk>/reschedule/', views.session_reschedule_view, name='session_reschedule'),
```

### 4. Create Templates

Create the following templates in `appointments/templates/appointments/`:

- `appointment_type_selection.html` - Choose single vs package
- `package_create_form.html` - Package creation form
- `provider_assignment_form.html` - Assign providers to sessions
- `package_detail.html` - View package details and sessions
- `package_list.html` - List all packages
- `package_cancel_form.html` - Cancel package confirmation
- `session_reschedule_form.html` - Reschedule individual session

### 5. Update Existing Appointment Form

Modify `appointments/templates/appointments/appointment_form.html`:
- Add appointment type selection at the top
- Show/hide fields based on selection
- Redirect to package flow if package selected

### 6. Add Navigation Links

Update navigation menus to include:
- "Create Package" link
- "View Packages" link
- Package count badges

### 7. Testing Checklist

#### Single Session Flow
- [ ] Create single session appointment (existing flow)
- [ ] Verify no changes to existing functionality
- [ ] Check appointment appears in calendar
- [ ] Test rescheduling and cancellation

#### Package Flow - Single Provider
- [ ] Create package with single provider
- [ ] Verify auto-scheduling works
- [ ] Check all sessions created with correct provider
- [ ] Verify appointments appear in calendar
- [ ] Test progress tracking
- [ ] Reschedule individual session
- [ ] Cancel entire package

#### Package Flow - Multiple Providers
- [ ] Create package with multiple providers
- [ ] Assign different provider to each session
- [ ] Verify auto-scheduling respects assignments
- [ ] Check each session has correct provider
- [ ] Test mixed completion (some done, some pending)

#### Preferred Days
- [ ] Create package with specific preferred days
- [ ] Verify sessions only scheduled on those days
- [ ] Test with no preferred days (any day)
- [ ] Test with limited availability on preferred days

#### Error Handling
- [ ] Test with no available slots
- [ ] Verify error messages stored
- [ ] Test manual rescheduling of failed sessions
- [ ] Check scheduling attempts counter

#### Admin Interface
- [ ] View packages in admin
- [ ] Edit package details
- [ ] View inline sessions
- [ ] Check progress display
- [ ] Filter and search packages

### 8. API Endpoints (Optional)

Consider adding REST API endpoints for:
- Package creation
- Package listing and filtering
- Package details
- Session rescheduling
- Package cancellation
- Auto-scheduling trigger

### 9. Notifications

Integrate with existing notification system:
- Send confirmation when package created
- Notify patient of all scheduled sessions
- Send reminders before each session
- Notify on package completion

### 10. Reporting

Add reports for:
- Package completion rates
- Average sessions per package
- Most common package types
- Provider utilization in packages
- Scheduling success rates

## Technical Notes

### Performance Considerations
- Use `select_related()` and `prefetch_related()` for package queries
- Index on `package_number`, `status`, `scheduled_date`
- Consider caching for frequently accessed packages

### Security
- Ensure tenant isolation for all package queries
- Validate user permissions for package operations
- Audit all package modifications via simple-history

### Scalability
- Auto-scheduling limited to 90-day window
- Maximum 100 sessions per package
- Consider background tasks for large packages (Celery)

### Data Integrity
- Use database transactions for package creation
- Cascade delete handled properly
- Orphaned appointments prevented via foreign keys

## Files Created/Modified

### New Files
1. `appointments/package_models.py` - Package data models
2. `appointments/package_scheduling_service.py` - Auto-scheduling logic
3. `appointments/package_forms.py` - Package forms
4. `PACKAGE_APPOINTMENTS_IMPLEMENTATION.md` - This document

### Modified Files
1. `appointments/models.py` - Added package model imports
2. `appointments/admin.py` - Added package admin classes

### Files to Create (Next Steps)
1. Migration files (auto-generated)
2. Package views in `appointments/views.py`
3. Package templates (7 templates)
4. URL patterns in `appointments/urls.py`

## Benefits

1. **Flexibility**: Support both single sessions and multi-session packages
2. **Automation**: Auto-scheduling saves time and reduces errors
3. **Scalability**: Handle packages from 2 to 100 sessions
4. **Provider Management**: Support for single or multiple providers
5. **Patient Preferences**: Respect preferred days for scheduling
6. **Progress Tracking**: Real-time visibility into package completion
7. **Error Recovery**: Graceful handling of scheduling failures
8. **Audit Trail**: Complete history via simple-history integration

## Conclusion

The package appointment system is now fully implemented at the model, service, form, and admin levels. The next steps involve creating the views, templates, and URLs to expose this functionality to end users. The system is designed to be flexible, scalable, and user-friendly while maintaining data integrity and security.

## Support

For questions or issues with this implementation, refer to:
- Django documentation: https://docs.djangoproject.com/
- Simple History: https://django-simple-history.readthedocs.io/
- Crispy Forms: https://django-crispy-forms.readthedocs.io/