iyzico Installment for WooCommerce

The iyzico Installment plugin displays installment options to your customers using iyzico's installment calculation on WooCommerce product pages. This plugin only displays installment information and does not process payments.

🚀 Features

• Product Page Integration: Automatic installment display on WooCommerce product pages
• Dynamic Installment Calculation: Real-time installment updates for price changes in variable products
• iyzico API Integration: Real-time installment calculation
• Multiple Integration Options: Use as shortcode, product tab, or widget
• AJAX Support: Dynamic installment calculation and updates
• Responsive Design: Mobile and desktop compatible
• Bank Logos: Automatic logo display by credit card families
• VAT Calculation: Option to include VAT in product prices
• HPOS Compatibility: WooCommerce High-Performance Order Storage support
• Multi-language Support: i18n integration
• Advanced Logging: Detailed error tracking and debug information

📋 Requirements

• WordPress: 6.6.2 or higher
• WooCommerce: 9.3.3 or higher
• PHP: 7.4.33 or higher
• cURL Extension: PHP cURL support
• iyzico WooCommerce: Main payment plugin
• iyzico Account: API access for installment calculation

🛠️ Installation

Installation from WordPress.org (Recommended)

1. Go to Plugins > Add New in your WordPress admin panel
2. Type "iyzico Installment" in the search box
3. Find the plugin and click the Install button
4. After installation is complete, click the Activate button

Manual Installation

1. Download the plugin ZIP file
2. Go to Plugins > Add New in your WordPress admin panel
3. Click the Upload Plugin button
4. Select the downloaded ZIP file and click the Install Now button
5. After installation is complete, click the Activate Plugin button

⚙️ Configuration

1. API Credentials

You need to enter your iyzico account information to use the plugin:

1. Go to the iyzico Installment page
2. Fill in the API Key and Secret Key fields
3. Select Test Mode or Live Mode
4. Click the Save button

2. Integration Type

The plugin offers three different integration types:

• Shortcode: Display anywhere using [iyzico_installment] or [dynamic_iyzico_installment]
• Product Tab: Automatically adds installment tab on product pages
• Widget: Display installment information in sidebar or footer

3. Display Settings

• Installment Tab Display: Add installment tab on product pages
• Responsive Design: Mobile-compatible display

🔧 Usage

Shortcode Usage

To display installment information on any page or post:

[iyzico_installment]

Dynamic Installment Shortcode

For real-time installment updates in variable products:

[dynamic_iyzico_installment]

Usage with PHP Code

// To get installment information programmatically
$installment_info = $GLOBALS['iyzico_api']->get_installment_info($product_price);

// To render the shortcode
echo do_shortcode('[iyzico_installment]'); // or [dynamic_iyzico_installment]

Theme Integration

Automatic integration by adding to your functions.php file:

// Automatic installment display on product pages
add_action('woocommerce_single_product_summary', function() {
    echo do_shortcode('[iyzico_installment]'); // or [dynamic_iyzico_installment]
}, 25);

🏗️ Technical Architecture

The plugin has a modular structure:

iyzico-installment/
├── iyzico-installment.php          # Main plugin file
├── includes/                        # Class files
│   ├── class-iyzico-installment-settings.php    # Settings management
│   ├── class-iyzico-installment-api.php         # API integration
│   ├── class-iyzico-installment-frontend.php    # Frontend operations
│   ├── class-iyzico-installment-dynamic.php     # Dynamic installment system
│   ├── class-iyzico-installment-logger.php      # Logging system
│   ├── class-iyzico-installment-hpos.php        # HPOS compatibility
│   └── admin/                      # Admin panel
├── assets/                         # CSS, JS and images
│   ├── css/                        # Style files
│   ├── js/                         # JavaScript files
│   └── images/                     # Bank logos
├── i18n/                           # Language files
└── logs/                           # Log files

Class Structure

• Settings: Manages plugin settings
• API: Provides iyzico API integration
• Frontend: User interface and shortcode operations
• Dynamic: Dynamic installment calculation for variable products
• Logger: Error tracking and debug information
• HPOS: WooCommerce High-Performance Order Storage compatibility
• Admin: Admin panel settings

🔌 API Integration

The plugin uses iyzico's official PHP SDK:

use Iyzipay\Model\InstallmentInfo;
use Iyzipay\Options;
use Iyzipay\Request\RetrieveInstallmentInfoRequest;

// Get installment information
$request = new RetrieveInstallmentInfoRequest();
$request->setLocale('tr');
$request->setConversationId(uniqid('iyzico_installment_'));
$request->setPrice($product_price);
$request->setBinNumber($bin_number);

$response = InstallmentInfo::retrieve($request, $options);

🎨 Customization

CSS Customization

You can customize the plugin's appearance through the admin panel. You can add your own style codes to the "Custom CSS" field in the admin panel:

/* Installment container */
.iyzico-installment-container {
    background: #ffffff;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 20px;
}

/* Bank cards */
.iyzico-bank-card {
    background: #fafafa;
    border: 1px solid #ddd;
    border-radius: 6px;
    padding: 15px;
    transition: all 0.3s ease;
}

.iyzico-bank-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
}

For more detailed examples, check the style.css file.

JavaScript Customization

Secure JavaScript operations for dynamic installment updates:

// Debug function - only works in WP_DEBUG mode
function debugLog(message, data) {
    if (window.installment_ajax && window.installment_ajax.debug && typeof console !== 'undefined') {
        if (data !== undefined) {
            console.log(message, data);
        } else {
            console.log(message);
        }
    }
}

// Listen for variation changes
jQuery(document).on('found_variation', 'form.variations_form', function(event, variation) {
    if (variation && variation.display_price) {
        var finalPrice = parseFloat(variation.display_price);

        // VAT calculation
        if (window.installment_ajax && window.installment_ajax.vat_enabled === 'true') {
            var vatRate = parseFloat(window.installment_ajax.vat_rate) || 0;
            finalPrice = finalPrice * (1 + (vatRate / 100));
        }

        debugLog('Final price with VAT:', finalPrice);
        loadInstallments(finalPrice);
    }
});

// Secure installment information loading
function loadInstallments(price) {
    // Price validation
    if (!price || price <= 0 || isNaN(price)) {
        debugLog('Invalid price:', price);
        return;
    }

    // AJAX object existence check
    if (!window.installment_ajax) {
        debugLog('installment_ajax object not found');
        return;
    }

    jQuery.ajax({
        url: window.installment_ajax.ajax_url,
        type: 'POST',
        data: {
            action: 'get_installment_options',
            price: price,
            product_id: parseInt(window.installment_ajax.product_id) || 0,
            nonce: window.installment_ajax.nonce
        },
        timeout: 10000, // 10 second timeout
        success: function(response) {
            debugLog('AJAX Response:', response);

            if (response && response.success) {
                // response.data is already sanitized with wp_kses_post() on server side
                jQuery('.dynamic-iyzico-installment').html(response.data);
            } else {
                // Show error messages securely - XSS protection
                var errorMsg = (response && response.data) ? String(response.data) : 'Unknown error';
                var sanitizedError = jQuery('<div>').text(errorMsg).html();
                jQuery('.dynamic-iyzico-installment').html('<p>Error: ' + sanitizedError + '</p>');
            }
        },
        error: function(xhr, status, error) {
            debugLog('AJAX Error - Status:', status);
            debugLog('AJAX Error - Error:', error);

            // Don't show technical details to user - security
            var userMessage = 'Connection error. Please try again.';

            // Special message for timeout
            if (status === 'timeout') {
                userMessage = 'Request timed out. Please try again.';
            }

            jQuery('.dynamic-iyzico-installment').html('<p>' + userMessage + '</p>');
        }
    });
}

🐛 Troubleshooting

Common Issues

Installment information not displaying:

• Check API credentials
• Ensure WooCommerce is active
• Check if dynamic installment setting is enabled
• Review log files

Installment not updating on variations:

• Check JavaScript errors (Browser Console)
• Ensure AJAX requests are successful
• Verify nonce value is correct

Getting API errors:

• Check if API Key and Secret Key are correct
• Check Test/Live mode setting
• Ensure cURL extension is active

📱 Responsive Design

The plugin works compatible on all devices:

• Desktop: Full-width table view
• Tablet: Medium-sized table view
• Mobile: Vertical list view

🌐 Multi-language Support

The plugin uses i18n standards:

• Turkish: Default language
• English: Translation files available
• Custom Translations: Can be added in languages/ folder

🔒 Security

• Nonce Control: Security in AJAX requests
• Rate Limiting: Protection against DDoS attacks (15 req/min per IP)
• ABSPATH Check: Prevent direct access
• Advanced CSS Sanitization: Secure style addition with XSS protection
• Production-Safe Debugging: Controlled log system in debug mode
• API Security: iyzico's secure API protocol
• WordPress Standards: WordPress coding standards compliant
• Input/Output Sanitization: Security checks on all data inputs

📊 Performance

• Lazy Loading: Load scripts only on necessary pages
• AJAX Caching: Cache installment information
• Database Optimization: Optimize database queries

🤝 Contributing

1. Fork this repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push your branch (git push origin feature/amazing-feature)
5. Create a Pull Request

📄 License

This project is licensed under the GPL v2 license.

📞 Support

• Technical Support: iyzico Customer Service
• Documentation: iyzico Developer Portal
• GitHub Issues: Repository Issues

🔄 Updates

v1.1.0

• Dynamic Installment System: Real-time installment updates for variable products
• VAT Calculation: Option to include VAT in product prices
• AJAX Security: Nonce control and security improvements
• CSS Optimization: Responsive design improvements

v1.0.0

• Initial release
• WooCommerce product page integration
• iyzico installment calculation integration
• Display installment options
• Responsive design
• HPOS compatibility
• Advanced logging system

📝 Changelog

For detailed changelist, see CHANGELOG.md file.

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iyzico Installment - Professional installment solution for WooCommerce