Digital Voucher System with Cash Entity

Overview

The Digital Voucher System is designed to manage and redeem vouchers that may include monetary value (cash), specific validation rules, feedback mechanisms, and instructions for issuing or redeeming vouchers. This system includes robust handling for cash entities that are tightly integrated with redeemable vouchers.

This document outlines the Cash entity, its relationship to the voucher system, and its critical features like tagging, status management, redemption rules, and validation.

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Core Components

1. Cash Entity (Cash Model):

   • Represents a monetary value or cash amount tied to a voucher.
   • Features secure handling with hashed secrets for redemption.
   • Enables tagging, tracking statuses, and metadata storage.
   • Supports advanced validation, including expiry and custom rules.

2. Voucher Entity (Voucher Model):

   • Represents the actual voucher, which may reference associated Cash.
   • Includes instructions for issuing or redeeming vouchers (e.g., feedback or rider instructions).

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Features of the Cash Model

1. Attributes

• amount: Represents the monetary value in minor units using the Brick\Money library.
• currency: Default to PHP but configurable on creation.
• meta: Stores custom metadata (ArrayObject).
• secret: A hashed value used for secure redemption.
• expires_on: Specifies when the cash expires.
• status: Tracks the current status of the cash (e.g., MINTED, EXPIRED).
• reference: A morph-to relationship to link cash to a voucher or any reference.

2. Status Management

• Uses the Spatie HasStatuses trait for dynamic status management.
• Allows status tracking with reasons for changes.
• Provides methods like:
  • setStatus(CashStatus $status, string $reason = null)
  • hasStatus(CashStatus $status)
  • hasHadStatus(CashStatus $status)
  • getCurrentStatus()

3. Tagging

• Uses the Spatie HasTags trait for adding tags to cash.
• Supports:
  • Attaching/detaching tags.
  • Querying models by tags.
  • Setting translated tags.

4. Secure Redemption

• Each cash entity includes a hashed secret for redemption validation:
  • Use setSecretAttribute to hash the secret before saving.
  • Validate with verifySecret(string $providedSecret).
• Combines expiration and secret-checking for redemption with canRedeem().

5. Validation and Metadata

• Custom validation rules are supported via CashValidationRulesData (e.g., location, country, and mobile validations).
• Metadata extends flexibility, allowing custom annotations when linking to vouchers.

6. Integration with Vouchers

• A Cash instance can reference a voucher via polymorphic relationships.
• Voucher instructions include:
  • cash validations and amounts.
  • Feedback and rider instructions.

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How It Works

Cash Creation

A Cash instance typically gets created and linked to a voucher:

use LBHurtado\Voucher\Models\Cash;
use Brick\Money\Money;

$cash = Cash::create([
    'amount' => Money::of(1000, 'PHP'), // 1,000 PHP in major units
    'currency' => 'PHP',
    'meta' => ['usage' => 'transport allowance'],
    'expires_on' => now()->addWeek(),
    'secret' => 'secure-secret-key', // Automatically hashed
]);

Redemption Validation

The canRedeem() method ensures that the cash:

1. Has not expired.
2. Matches the provided secret:

if ($cash->canRedeem($providedSecret)) {
    // Process redemption logic here
} else {
    // Handle failure (e.g., invalid secret or expired cash)
}

Status Tracking

Handle status changes such as MINTED, EXPIRED, or DISBURSED:

use LBHurtado\Voucher\Enums\CashStatus;

$cash->setStatus(CashStatus::DISBURSED, 'Funds disbursed for purchase');

Tagging Example

Tags can classify or group cash instances:

$cash->attachTags(['finance', 'budget']);
$cashWithTags = Cash::withAnyTags(['finance'])->get();

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Testing

Unit Testing

• The suite uses Pest for fast and expressive unit tests.
• Coverage for:
  • Validation: CashValidationRulesDataTest.php, CashInstructionDataTest.php
  • Secure redemption: CashSecretTest.php
  • Tagging: CashTagTest.php
  • Statuses: CashStatusTest.php
  • Instructions and metadata: VoucherInstructionsDataTest.php

Sample Test:

Tests ensure methods like canRedeem work as expected:

it('does not allow redemption if cash has expired', function () {
    $cash = Cash::factory()->create([
        'expires_on' => now()->subDay(), // Expired yesterday
        'secret' => 'secure-secret',
    ]);

    $validSecret = 'secure-secret';

    expect($cash->canRedeem($validSecret))->toBeFalse(); // Fails due to expiration
});

Run the test suite:

./vendor/bin/pest

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Code Structure

Models

• Cash: Core monetary entity with statuses, tags, and secure redemption.
• Voucher: A redeemable voucher that may have associated cash.

Data Classes

• CashValidationRulesData: For cash-specific validation rules (e.g., mobile, location).
• VoucherInstructionsData: Holds all voucher-related instructions.

Enums

• CashStatus: Tracks the current state of cash (e.g., MINTED, EXPIRED).
• VoucherInputField: Lists possible input fields for voucher instructions (e.g., MOBILE, EMAIL).

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Key Files

File	Purpose
CashTest.php	Core tests for Cash model functionality
CashSecretTest.php	Tests secure secret handling and redemption logic
CashStatusTest.php	Tests status management for Cash entity
CashTagTest.php	Tests tagging functionality for Cash entity
VoucherInstructionsDataTest	Tests voucher instructions and serialization

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Example Workflow

1. Create a Voucher with Cash:

Use structured data classes to create a voucher with cash, inputs, and validation:

$instructions = new VoucherInstructionsData([
    'cash' => [
        'amount' => 1000,
        'currency' => 'PHP',
        'validation' => [
            'secret' => 'secure-secret',
        ],
    ],
]);

$voucher = Vouchers::create([
    'metadata' => ['instructions' => $instructions],
]);

2. Redeem a Voucher:

Validate cash redemption:

$cash = $voucher->cash;

if ($cash->canRedeem($providedSecret)) {
    $cash->setStatus(CashStatus::DISBURSED);
}

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Conclusion

The Digital Voucher System with the Cash entity provides a robust framework for managing redeemable vouchers. Combined with secure secret handling, tagging, validation, and metadata storage, this system is designed to meet modern financial and transactional needs. Propel your application with this flexible and modular system! 🚀