# PayFast Package Refactoring Summary

## Overview

The PayFast package has been completely refactored to follow:

- **PSR-12** coding standards
- **Repository Pattern**
- **Service-Based Architecture** with Event-Driven components

## What Changed

### 1. Repository Pattern Implementation

**New Files:**

- `src/Repositories/Contracts/ProcessPaymentRepositoryInterface.php`
- `src/Repositories/ProcessPaymentRepository.php`

**Benefits:**

- Abstracted data access layer
- Easier to test and mock
- Follows Single Responsibility Principle

### 2. Service Layer Architecture

**New Services:**

- `Services/ConfigService.php` - Configuration management
- `Services/HttpClientService.php` - HTTP communication
- `Services/AuthenticationService.php` - Token management
- `Services/PaymentService.php` - Payment processing
- `Services/TransactionService.php` - Transaction queries

**All services have interfaces:**

- `Services/Contracts/HttpClientInterface.php`
- `Services/Contracts/AuthenticationServiceInterface.php`
- `Services/Contracts/PaymentServiceInterface.php`
- `Services/Contracts/TransactionServiceInterface.php`

### 3. Event-Based Architecture

**New Events:**

- `Events/PaymentInitiated.php`
- `Events/PaymentValidated.php`
- `Events/PaymentCompleted.php`
- `Events/PaymentFailed.php`
- `Events/TokenRefreshed.php`

**New Listeners:**

- `Listeners/LogPaymentActivity.php` - Logs all payment activities
- `Listeners/StorePaymentRecord.php` - Stores payment records

### 4. Data Transfer Objects (DTOs)

**New DTOs:**

- `DTOs/PaymentRequestDTO.php` - Type-safe payment request data

### 5. Refactored Main Classes

**Updated:**

- `PayFast.php` - Now uses dependency injection and services
- `Interfaces/PaymentInterface.php` - Updated with proper types
- `Helpers/Utility.php` - PSR-12 compliant
- `Models/ProcessPayment.php` - Added proper docblocks
- `Facade/Payfast.php` - Added method annotations
- `Provider/PayFastServiceProvider.php` - Proper DI container setup

## Architecture Decision

**Recommended: Service-Based Architecture with Event-Driven Components**

See `ARCHITECTURE.md` for detailed explanation.

### Why Service-Based?

- Payment gateways need synchronous, sequential operations
- Better error handling and transaction management
- Easier to test and debug
- Clear control flow

### Why Events?

- Used for side effects (logging, notifications, analytics)
- Doesn't block main payment flow
- Allows extensibility without modifying core code

## Code Quality Improvements

### PSR-12 Compliance

- Proper spacing: `public function method() {` → `public function method(): void {`
- Type declarations on all methods
- `declare(strict_types=1)` in all files
- Consistent naming (camelCase for methods)
- Proper visibility modifiers

### Design Principles

**Single Responsibility:**

- Each service has one job
- Repository only handles data access
- Services don't mix concerns

**Open/Closed:**

- Extend via events without modifying core
- New features via listeners

**Liskov Substitution:**

- All implementations follow their interfaces
- Can swap implementations easily

**Interface Segregation:**

- Small, focused interfaces
- No fat interfaces

**Dependency Inversion:**

- Depend on abstractions (interfaces)
- All dependencies injected

## Breaking Changes

### Method Naming

- `GetToken()` → `getToken()`
- `RefreshToken()` → `refreshToken()`
- `GetOTPScreen()` → `getOTPScreen()`
- All methods now follow camelCase (PSR-12)

### Class Structure

- `PayFast` no longer extends `PayfastService`
- Uses dependency injection instead
- Old `Payment` class is deprecated

### Response Handling

- More consistent response format
- Better error handling
- Type-safe responses

## Migration Guide

### Old Code:

```php
$payfast = new PayFast();
$result = $payfast->GetToken();
```

### New Code:

```php
$payfast = app('payfast'); // or use facade
$result = $payfast->getToken();
```

### Using Events:

```php
use zfhassaan\Payfast\Events\PaymentCompleted;

Event::listen(PaymentCompleted::class, function ($event) {
    // Handle payment completion
    Mail::send(...);
});
```

## Testing

All services can now be easily tested:

```php
// Mock the HTTP client
$httpClient = Mockery::mock(HttpClientInterface::class);
$httpClient->shouldReceive('post')->andReturn(['code' => '00']);

// Test authentication service
$authService = new AuthenticationService($httpClient, $configService);
$result = $authService->getToken();
```

## File Structure

```
src/
├── DTOs/
│   └── PaymentRequestDTO.php
├── Events/
│   ├── PaymentCompleted.php
│   ├── PaymentFailed.php
│   ├── PaymentInitiated.php
│   ├── PaymentValidated.php
│   └── TokenRefreshed.php
├── Listeners/
│   ├── LogPaymentActivity.php
│   └── StorePaymentRecord.php
├── Repositories/
│   ├── Contracts/
│   │   └── ProcessPaymentRepositoryInterface.php
│   └── ProcessPaymentRepository.php
├── Services/
│   ├── Contracts/
│   │   ├── AuthenticationServiceInterface.php
│   │   ├── HttpClientInterface.php
│   │   ├── PaymentServiceInterface.php
│   │   └── TransactionServiceInterface.php
│   ├── AuthenticationService.php
│   ├── ConfigService.php
│   ├── HttpClientService.php
│   ├── PaymentService.php
│   └── TransactionService.php
├── Helpers/
│   └── Utility.php (refactored)
├── Interfaces/
│   └── PaymentInterface.php (updated)
├── Models/
│   └── ProcessPayment.php (updated)
├── Facade/
│   └── Payfast.php (updated)
├── Provider/
│   └── PayFastServiceProvider.php (refactored)
└── PayFast.php (completely refactored)
```

## Next Steps

1. **Remove deprecated classes:**

   - `Payment.php` (old implementation)
   - `Helpers/PayfastService.php` (replaced by services)
   - `Helpers/ConfigLoader.php` (replaced by ConfigService)
   - `Helpers/HttpCommunicator.php` (replaced by HttpClientService)

2. **Add unit tests** for all services

3. **Add integration tests** for payment flows

4. **Update documentation** with new examples

5. **Version bump** to 2.0.0 (breaking changes)

## Benefits Summary

**Maintainability**: Clear separation of concerns  
 **Testability**: Easy to unit test each component  
 **Extensibility**: Add features via events or services  
 **Type Safety**: Strong typing throughout  
 **PSR-12 Compliant**: Follows coding standards  
 **Repository Pattern**: Clean data access layer
