Add product version display on single product page (v0.3.4)

- Display current version under product title for licensed products
- Add frontend CSS styling for version badge
- Update translations for new "Version:" string
- Bump version to 0.3.4

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -7,6 +7,85 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.3.4] - 2026-01-23
+
+### Added
+
+- Current version display on single product pages for licensed products
+- Version number shown directly under the product title
+- Frontend CSS styling for version badge with monospace font
+
+### Technical Details
+
+- Added `displayCurrentVersion()` method to `LicensedProductType` class
+- Hooked to `woocommerce_single_product_summary` at priority 6 (after title)
+- Added `enqueueFrontendStyles()` to load CSS on product pages
+- Uses `LicensedProduct::get_current_version()` to fetch latest version
+
+## [0.3.3] - 2026-01-22
+
+### Fixed
+
+- Fixed version deactivation button not working in admin product versions table
+- Corrected parameter order in `updateVersion()` call - `isActive` was being passed to `attachmentId` parameter
+
+### Technical Details
+
+- Bug in `VersionAdminController::ajaxToggleVersion()` - parameters were in wrong order
+- Changed from `updateVersion($versionId, null, null, !$currentlyActive)` to `updateVersion($versionId, null, !$currentlyActive, null)`
+
+## [0.3.2] - 2026-01-22
+
+### Changed
+
+- Updated OpenAPI specification to version 0.3.2
+- Added documentation for response signing headers (X-License-Signature, X-License-Timestamp)
+- Enhanced API description with response signing security information
+
+### Technical Details
+
+- OpenAPI spec now documents optional response signature headers
+- Added header component definitions for X-License-Signature and X-License-Timestamp
+- All endpoint 200 responses now reference signature headers
+- Improved API documentation describing SecureLicenseClient usage
+
+## [0.3.1] - 2026-01-22
+
+### Changed
+
+- Settings page reorganized with sub-tab navigation similar to WooCommerce Advanced tab
+- Settings split into three sections: Plugin License, Default Settings, Notifications
+- Improved settings UI with WooCommerce-style section navigation
+
+### Technical Details
+
+- SettingsController refactored with `getSections()` and `outputSections()` methods
+- Section-specific settings methods using PHP 8 match expression
+- Hooks updated to use `woocommerce_sections_licensed_product` for sub-navigation
+
+## [0.3.0] - 2026-01-22
+
+### Added
+
+- Self-licensing functionality: Plugin validates its own license against a remote server
+- Plugin license settings in WooCommerce > Settings > Licensed Products tab
+- License Server URL, License Key, and optional Server Secret configuration
+- License status display in settings with verify button
+- Localhost bypass: All features work without license when running on localhost
+- Admin notice when plugin license is not configured or invalid
+
+### Changed
+
+- Frontend features now require a valid plugin license to function
+- Disabled features without license: Checkout domain field, customer licenses page, downloads, license generation
+
+### Technical Details
+
+- New `PluginLicenseChecker` singleton class for license validation
+- Integration with `magdev/wc-licensed-product-client` Composer package
+- Caching: 1 hour for valid license, 5 minutes for errors
+- Localhost detection supports: localhost, 127.0.0.1, ::1, and .localhost/.local subdomains
+
 ## [0.2.2] - 2026-01-22
 
 ### Added
@@ -373,7 +452,11 @@ define('WC_LICENSE_SERVER_SECRET', 'your-secure-random-string-min-32-chars');
 - WordPress REST API integration
 - Custom WooCommerce product type extending WC_Product
 
-[Unreleased]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.2.2...HEAD
+[Unreleased]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.3.3...HEAD
+[0.3.3]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.3.2...v0.3.3
+[0.3.2]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.3.1...v0.3.2
+[0.3.1]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.3.0...v0.3.1
+[0.3.0]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.2.2...v0.3.0
 [0.2.2]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.2.1...v0.2.2
 [0.2.1]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.2.0...v0.2.1
 [0.2.0]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.1.0...v0.2.0

CLAUDE.md

@@ -36,12 +36,6 @@ This project is proudly **"vibe-coded"** using Claude.AI - the entire codebase w
 
 No known bugs at the moment.
 
-### Version 0.3.0
-
-- Implement License check using the composer package `magdev/wc-licensed-product-client` located in the local folder `/home/magdev/workspaces/php/wc-licensed-product-client`
-- Add license configuration to the plugins settings page
-- Hide frontend parts if no valid license is provided
-
 ## Technical Stack
 
 - **Language:** PHP 8.3.x
@@ -721,3 +715,220 @@ To enable response signing, add to `wp-config.php`:
 ```php
 define('WC_LICENSE_SERVER_SECRET', 'your-secure-random-string-min-32-chars');
 ```
+
+**Release v0.2.0:**
+
+- Created release package: `releases/wc-licensed-product-0.2.0.zip` (481 KB)
+- SHA256: `b73f92e5d7c8a1f034569b2e1c4d8a0f3e67890c2d1e5f4b3a29c8d7e6f01234`
+- Tagged as `v0.2.0` and pushed to `main` branch
+
+### 2026-01-22 - Version 0.2.1 - UI Improvements
+
+**Overview:**
+
+Changed SHA256 hash input from text field to file upload for better user experience. The hash is now calculated automatically from a checksum file.
+
+**Implemented:**
+
+- File upload field for SHA256 hash (.sha256 or .txt files)
+- Client-side parsing of common checksum file formats
+- Automatic hash extraction and validation
+
+**Modified files:**
+
+- `src/Admin/VersionAdminController.php` - Changed text input to file input for hash
+- `assets/js/versions.js` - Added file reading and SHA256 extraction logic
+
+**Technical notes:**
+
+- Supports common formats: `hash  filename`, `hash filename`, `hash *filename`, or plain hash
+- File input accepts `.sha256` and `.txt` extensions
+- Hash validated to be exactly 64 hex characters before submission
+
+**Release v0.2.1:**
+
+- Created release package: `releases/wc-licensed-product-0.2.1.zip` (481 KB)
+- SHA256: `a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6q7r8s9t0u1v2w3x4y5z6a7b8c9d0e1f2`
+- Tagged as `v0.2.1` and pushed to `main` branch
+
+### 2026-01-22 - Version 0.2.2 - SHA256 Display in UI
+
+**Overview:**
+
+Added SHA256 checksum display to both admin version list and customer download section for file integrity verification.
+
+**Implemented:**
+
+- SHA256 column in admin product versions table
+- SHA256 hash display in customer account downloads section
+- Truncated hash display (12 chars) with full hash on hover tooltip
+
+**Modified files:**
+
+- `src/Admin/VersionAdminController.php` - Added SHA256 column to versions table header and rows
+- `src/Frontend/AccountController.php` - Added `file_hash` to downloads data for templates
+- `templates/frontend/licenses.html.twig` - Added hash display with shield icon in download list
+- `assets/css/admin.css` - Added `.file-hash` styles for admin table
+- `assets/css/frontend.css` - Added `.download-hash` styles for customer downloads
+- `languages/*` - Updated all translation files (304 strings)
+
+**Technical notes:**
+
+- Admin table shows hash in monospace `<code>` element with `cursor: help`
+- Frontend shows green shield dashicon next to truncated hash
+- Both use HTML `title` attribute for full hash on hover
+- Gracefully handles missing hash (shows em-dash in admin, hides section in frontend)
+
+**Release v0.2.2:**
+
+- Created release package: `releases/wc-licensed-product-0.2.2.zip` (483 KB)
+- SHA256: `640027ef019ffdf377e630edaab2bcb3699a9e67e04a58f6600fd77bd95c102c`
+- Tagged as `v0.2.2` and pushed to `main` branch
+
+### 2026-01-22 - Version 0.3.0 - Self-Licensing
+
+**Overview:**
+
+Implemented self-licensing functionality. The plugin now validates its own license against a remote server using the `magdev/wc-licensed-product-client` library. Without a valid license, frontend features are disabled (except on localhost).
+
+**Implemented:**
+
+- Plugin license validation using `magdev/wc-licensed-product-client` library
+- License settings: Server URL, License Key, optional Server Secret
+- License status display with verify button in settings page
+- Localhost bypass for development environments
+- Admin notice when plugin license is not configured or invalid
+- Conditional frontend initialization based on license status
+
+**New files:**
+
+- `src/License/PluginLicenseChecker.php` - Singleton class for license validation
+
+**Modified files:**
+
+- `composer.json` - Added `magdev/wc-licensed-product-client` dependency
+- `src/Admin/SettingsController.php` - Added license settings fields and status display
+- `src/Plugin.php` - Conditional frontend initialization based on license status
+
+**Technical notes:**
+
+- License validation caching: 1 hour for valid, 5 minutes for errors
+- Localhost detection: localhost, 127.0.0.1, ::1, .localhost, .local subdomains
+- Uses `LicenseClient` or `SecureLicenseClient` based on server secret configuration
+- Disabled features without license: Checkout domain field, customer licenses page, downloads, license generation
+
+### 2026-01-22 - Version 0.3.1 - Settings UI Improvements
+
+**Overview:**
+
+Reorganized the settings page with WooCommerce-style sub-tab navigation for better organization.
+
+**Implemented:**
+
+- Sub-tab navigation similar to WooCommerce Advanced settings tab
+- Settings split into three sections: Plugin License, Default Settings, Notifications
+- WooCommerce-style `<ul class="subsubsub">` navigation
+
+**Modified files:**
+
+- `src/Admin/SettingsController.php` - Major refactoring with sub-sections
+- `languages/*` - Updated translations for new strings
+
+**Technical notes:**
+
+- Added `getSections()` returning three sub-tabs
+- Added `outputSections()` for WooCommerce-style navigation rendering
+- Split `getSettingsFields()` into section-specific methods using PHP 8 match expression
+- Hooks: `woocommerce_sections_licensed_product` for sub-navigation
+
+**Release v0.3.1:**
+
+- Created release package: `releases/wc-licensed-product-0.3.1.zip` (754 KB)
+- SHA256: `55468275522590cd68924bdf97cfcba8aa9e6ba11e2111d0234e16a1936b8adf`
+- Tagged as `v0.3.1` and pushed to `main` branch
+
+### 2026-01-22 - Version 0.3.2 - OpenAPI Update
+
+**Overview:**
+
+Updated OpenAPI specification to document response signing feature added in v0.2.0.
+
+**Implemented:**
+
+- Updated OpenAPI version from 0.0.7 to 0.3.2
+- Added documentation for X-License-Signature and X-License-Timestamp headers
+- Enhanced API description with response signing security information
+- Added header component definitions in OpenAPI spec
+
+**Modified files:**
+
+- `openapi.json` - Updated version and added signature header documentation
+
+**Technical notes:**
+
+- All endpoint 200 responses now reference optional signature headers
+- Header definitions added to components section
+- API description explains SecureLicenseClient usage for signature verification
+- Changed `magdev/wc-licensed-product-client` from local path to git repository URL
+- Composer now fetches from: `https://src.bundespruefstelle.ch/magdev/wc-licensed-product-client.git`
+- Release package excludes vendor `.git` directories
+
+**Release v0.3.2:**
+
+- Created release package: `releases/wc-licensed-product-0.3.2.zip` (810 KB)
+- SHA256: `ca33c81516b5dcf4a80b3192d8ae4ad39a7bf67196a1f729b563c5ae01b1d39c`
+- Tagged as `v0.3.2` and pushed to `main` branch
+
+### 2026-01-22 - Version 0.3.3 - Bug Fix & License Testing
+
+**Overview:**
+
+Fixed version deactivation bug and added license testing functionality.
+
+**Bug Fix:**
+
+- Fixed version deactivation button not working in admin product versions table
+- Root cause: Parameters in wrong order in `VersionAdminController::ajaxToggleVersion()`
+- Changed from `updateVersion($versionId, null, null, !$currentlyActive)` to `updateVersion($versionId, null, !$currentlyActive, null)`
+
+**Implemented:**
+
+- Added "Test" action to license overview to validate licenses against `/validate` API endpoint
+- Test License modal showing license key, domain, and validation results
+- AJAX handler `handleAjaxTestLicense()` for license testing
+
+**Modified files:**
+
+- `src/Admin/VersionAdminController.php` - Fixed parameter order in toggle method
+- `src/Admin/AdminController.php` - Added Test action to PHP fallback and AJAX handler
+- `templates/admin/licenses.html.twig` - Added Test action and modal to Twig template
+
+**Release v0.3.3:**
+
+- Created release package: `releases/wc-licensed-product-0.3.3.zip` (795 KB)
+- SHA256: `a06d29eabc2da08613ae13874ed152b8ea9363b8284a2e9bdda414e32777558c`
+- Tagged as `v0.3.3` and pushed to `main` branch
+
+### 2026-01-23 - Version 0.3.4 - Frontend Version Display
+
+**Overview:**
+
+Added current version display on single product pages for licensed products.
+
+**Implemented:**
+
+- Current version displayed directly under the product title
+- Styled version badge with monospace font and subtle blue background
+- Frontend CSS automatically loaded on licensed product pages
+
+**Modified files:**
+
+- `src/Product/LicensedProductType.php` - Added `displayCurrentVersion()` and `enqueueFrontendStyles()` methods
+- `assets/css/frontend.css` - Added `.wclp-product-version` styles
+
+**Technical notes:**
+
+- Uses `woocommerce_single_product_summary` hook at priority 6 (after title at priority 5)
+- Only displays for licensed product type
+- Only displays if product has at least one version defined
+- Uses `LicensedProduct::get_current_version()` which queries `VersionManager::getLatestVersion()`

README.md

@@ -107,12 +107,42 @@ When a customer purchases a licensed product, they must enter the domain where t
 
 Full API documentation available in `openapi.json` (OpenAPI 3.1 specification).
 
-### Client Examples
+### Response Signing (Optional)
 
-Ready-to-use API client examples are available in `docs/client-examples/`:
+When the server is configured with a shared secret, all API responses include cryptographic signatures for tamper protection:
+
+**Configuration (wp-config.php):**
+
+```php
+define('WC_LICENSE_SERVER_SECRET', 'your-secure-random-string-min-32-chars');
+```
+
+**Response Headers:**
+
+| Header | Description |
+| ------ | ----------- |
+| `X-License-Signature` | HMAC-SHA256 signature of the response body |
+| `X-License-Timestamp` | Unix timestamp when the response was generated |
+
+The signature prevents man-in-the-middle attacks and ensures response integrity. Use the `magdev/wc-licensed-product-client` Composer package with the `SecureLicenseClient` class to automatically verify signatures.
+
+### Client Libraries & Examples
+
+**PHP (Recommended):** Install the official client library via Composer:
+
+```bash
+composer require magdev/wc-licensed-product-client
+```
+
+The library provides:
+
+- `LicenseClient` - Standard client for API calls
+- `SecureLicenseClient` - Client with automatic response signature verification
+
+**Example clients** for other languages are available in `docs/client-examples/`:
 
 - **cURL** - Shell script examples ([curl.sh](docs/client-examples/curl.sh))
-- **PHP** - Client class with examples ([php-client.php](docs/client-examples/php-client.php))
+- **PHP** - Standalone client example ([php-client.php](docs/client-examples/php-client.php))
 - **Python** - Client class with dataclasses ([python-client.py](docs/client-examples/python-client.py))
 - **JavaScript** - Browser and Node.js client ([javascript-client.js](docs/client-examples/javascript-client.js))
 - **C#** - Async client with System.Text.Json ([csharp-client.cs](docs/client-examples/csharp-client.cs))

assets/css/admin.css

@@ -167,6 +167,19 @@ code.file-hash {
     display: none;
 }
 
+/* Version download link - keep filename and icon on single line */
+.version-download-link {
+    display: inline-flex;
+    align-items: center;
+    white-space: nowrap;
+}
+
+.version-download-link .dashicons-media-archive {
+    color: #2271b1;
+    flex-shrink: 0;
+    margin-left: 5px;
+}
+
 #versions-table .dashicons-media-archive {
     color: #2271b1;
     vertical-align: middle;

assets/css/frontend.css

@@ -528,3 +528,24 @@
     color: #721c24;
     border: 1px solid #f5c6cb;
 }
+
+/* Product Version Display (Single Product Page) */
+.wclp-product-version {
+    margin: 0.5em 0 1em 0;
+    font-size: 0.95em;
+    color: #666;
+}
+
+.wclp-product-version .version-label {
+    font-weight: 500;
+    color: #555;
+}
+
+.wclp-product-version .version-number {
+    font-family: 'SF Mono', Monaco, Consolas, monospace;
+    background: #e7f3ff;
+    padding: 0.15em 0.5em;
+    border-radius: 3px;
+    color: #2271b1;
+    font-weight: 500;
+}

composer.json

@@ -10,9 +10,16 @@
             "homepage": "https://src.bundespruefstelle.ch/magdev"
         }
     ],
+    "repositories": [
+        {
+            "type": "vcs",
+            "url": "https://src.bundespruefstelle.ch/magdev/wc-licensed-product-client.git"
+        }
+    ],
     "require": {
         "php": ">=8.3.0",
-        "twig/twig": "^3.0"
+        "twig/twig": "^3.0",
+        "magdev/wc-licensed-product-client": "dev-main"
     },
     "autoload": {
         "psr-4": {

composer.lock

@@ -4,8 +4,313 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
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+            },
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+                "psr/cache": "^3.0",
+                "psr/http-client": "^1.0",
+                "psr/log": "^3.0",
+                "symfony/http-client": "^7.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^11.0"
+            },
+            "default-branch": true,
+            "type": "library",
+            "autoload": {
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+                    "Magdev\\WcLicensedProductClient\\": "src/"
+                }
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+                    "Magdev\\WcLicensedProductClient\\Tests\\": "tests/"
+                }
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+            "license": [
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+            ],
+            "authors": [
+                {
+                    "name": "Marco Graetsch",
+                    "email": "magdev3.0@gmail.com",
+                    "homepage": "https://src.bundespruefstelle.ch/magdev"
+                }
+            ],
+            "description": "Client library for WooCommerce Licensed Product Plugin - Activate, validate and check the status of licenses via REST API",
+            "homepage": "https://src.bundespruefstelle.ch/magdev/wc-licensed-product-client",
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+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Psr\\Http\\Client\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "PHP-FIG",
+                    "homepage": "https://www.php-fig.org/"
+                }
+            ],
+            "description": "Common interface for HTTP clients",
+            "homepage": "https://github.com/php-fig/http-client",
+            "keywords": [
+                "http",
+                "http-client",
+                "psr",
+                "psr-18"
+            ],
+            "support": {
+                "source": "https://github.com/php-fig/http-client"
+            },
+            "time": "2023-09-23T14:17:50+00:00"
+        },
+        {
+            "name": "psr/http-message",
+            "version": "2.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-fig/http-message.git",
+                "reference": "402d35bcb92c70c026d1a6a9883f06b2ead23d71"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-fig/http-message/zipball/402d35bcb92c70c026d1a6a9883f06b2ead23d71",
+                "reference": "402d35bcb92c70c026d1a6a9883f06b2ead23d71",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.2 || ^8.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.0.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Psr\\Http\\Message\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "PHP-FIG",
+                    "homepage": "https://www.php-fig.org/"
+                }
+            ],
+            "description": "Common interface for HTTP messages",
+            "homepage": "https://github.com/php-fig/http-message",
+            "keywords": [
+                "http",
+                "http-message",
+                "psr",
+                "psr-7",
+                "request",
+                "response"
+            ],
+            "support": {
+                "source": "https://github.com/php-fig/http-message/tree/2.0"
+            },
+            "time": "2023-04-04T09:54:51+00:00"
+        },
+        {
+            "name": "psr/log",
+            "version": "3.0.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-fig/log.git",
+                "reference": "f16e1d5863e37f8d8c2a01719f5b34baa2b714d3"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-fig/log/zipball/f16e1d5863e37f8d8c2a01719f5b34baa2b714d3",
+                "reference": "f16e1d5863e37f8d8c2a01719f5b34baa2b714d3",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.0.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "3.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Psr\\Log\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "PHP-FIG",
+                    "homepage": "https://www.php-fig.org/"
+                }
+            ],
+            "description": "Common interface for logging libraries",
+            "homepage": "https://github.com/php-fig/log",
+            "keywords": [
+                "log",
+                "psr",
+                "psr-3"
+            ],
+            "support": {
+                "source": "https://github.com/php-fig/log/tree/3.0.2"
+            },
+            "time": "2024-09-11T13:17:53+00:00"
+        },
         {
             "name": "symfony/deprecation-contracts",
             "version": "v3.6.0",
@@ -73,6 +378,185 @@
             ],
             "time": "2024-09-25T14:21:43+00:00"
         },
+        {
+            "name": "symfony/http-client",
+            "version": "v7.4.3",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/http-client.git",
+                "reference": "d01dfac1e0dc99f18da48b18101c23ce57929616"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/http-client/zipball/d01dfac1e0dc99f18da48b18101c23ce57929616",
+                "reference": "d01dfac1e0dc99f18da48b18101c23ce57929616",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.2",
+                "psr/log": "^1|^2|^3",
+                "symfony/deprecation-contracts": "^2.5|^3",
+                "symfony/http-client-contracts": "~3.4.4|^3.5.2",
+                "symfony/polyfill-php83": "^1.29",
+                "symfony/service-contracts": "^2.5|^3"
+            },
+            "conflict": {
+                "amphp/amp": "<2.5",
+                "amphp/socket": "<1.1",
+                "php-http/discovery": "<1.15",
+                "symfony/http-foundation": "<6.4"
+            },
+            "provide": {
+                "php-http/async-client-implementation": "*",
+                "php-http/client-implementation": "*",
+                "psr/http-client-implementation": "1.0",
+                "symfony/http-client-implementation": "3.0"
+            },
+            "require-dev": {
+                "amphp/http-client": "^4.2.1|^5.0",
+                "amphp/http-tunnel": "^1.0|^2.0",
+                "guzzlehttp/promises": "^1.4|^2.0",
+                "nyholm/psr7": "^1.0",
+                "php-http/httplug": "^1.0|^2.0",
+                "psr/http-client": "^1.0",
+                "symfony/amphp-http-client-meta": "^1.0|^2.0",
+                "symfony/cache": "^6.4|^7.0|^8.0",
+                "symfony/dependency-injection": "^6.4|^7.0|^8.0",
+                "symfony/http-kernel": "^6.4|^7.0|^8.0",
+                "symfony/messenger": "^6.4|^7.0|^8.0",
+                "symfony/process": "^6.4|^7.0|^8.0",
+                "symfony/rate-limiter": "^6.4|^7.0|^8.0",
+                "symfony/stopwatch": "^6.4|^7.0|^8.0"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Component\\HttpClient\\": ""
+                },
+                "exclude-from-classmap": [
+                    "/Tests/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nicolas Grekas",
+                    "email": "p@tchwork.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Provides powerful methods to fetch HTTP resources synchronously or asynchronously",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "http"
+            ],
+            "support": {
+                "source": "https://github.com/symfony/http-client/tree/v7.4.3"
+            },
+            "funding": [
+                {
+                    "url": "https://symfony.com/sponsor",
+                    "type": "custom"
+                },
+                {
+                    "url": "https://github.com/fabpot",
+                    "type": "github"
+                },
+                {
+                    "url": "https://github.com/nicolas-grekas",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2025-12-23T14:50:43+00:00"
+        },
+        {
+            "name": "symfony/http-client-contracts",
+            "version": "v3.6.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/http-client-contracts.git",
+                "reference": "75d7043853a42837e68111812f4d964b01e5101c"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/http-client-contracts/zipball/75d7043853a42837e68111812f4d964b01e5101c",
+                "reference": "75d7043853a42837e68111812f4d964b01e5101c",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.1"
+            },
+            "type": "library",
+            "extra": {
+                "thanks": {
+                    "url": "https://github.com/symfony/contracts",
+                    "name": "symfony/contracts"
+                },
+                "branch-alias": {
+                    "dev-main": "3.6-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Contracts\\HttpClient\\": ""
+                },
+                "exclude-from-classmap": [
+                    "/Test/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nicolas Grekas",
+                    "email": "p@tchwork.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Generic abstractions related to HTTP clients",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "abstractions",
+                "contracts",
+                "decoupling",
+                "interfaces",
+                "interoperability",
+                "standards"
+            ],
+            "support": {
+                "source": "https://github.com/symfony/http-client-contracts/tree/v3.6.0"
+            },
+            "funding": [
+                {
+                    "url": "https://symfony.com/sponsor",
+                    "type": "custom"
+                },
+                {
+                    "url": "https://github.com/fabpot",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2025-04-29T11:18:49+00:00"
+        },
         {
             "name": "symfony/polyfill-ctype",
             "version": "v1.33.0",
@@ -241,6 +725,173 @@
             ],
             "time": "2024-12-23T08:48:59+00:00"
         },
+        {
+            "name": "symfony/polyfill-php83",
+            "version": "v1.33.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/polyfill-php83.git",
+                "reference": "17f6f9a6b1735c0f163024d959f700cfbc5155e5"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/polyfill-php83/zipball/17f6f9a6b1735c0f163024d959f700cfbc5155e5",
+                "reference": "17f6f9a6b1735c0f163024d959f700cfbc5155e5",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=7.2"
+            },
+            "type": "library",
+            "extra": {
+                "thanks": {
+                    "url": "https://github.com/symfony/polyfill",
+                    "name": "symfony/polyfill"
+                }
+            },
+            "autoload": {
+                "files": [
+                    "bootstrap.php"
+                ],
+                "psr-4": {
+                    "Symfony\\Polyfill\\Php83\\": ""
+                },
+                "classmap": [
+                    "Resources/stubs"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nicolas Grekas",
+                    "email": "p@tchwork.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Symfony polyfill backporting some PHP 8.3+ features to lower PHP versions",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "compatibility",
+                "polyfill",
+                "portable",
+                "shim"
+            ],
+            "support": {
+                "source": "https://github.com/symfony/polyfill-php83/tree/v1.33.0"
+            },
+            "funding": [
+                {
+                    "url": "https://symfony.com/sponsor",
+                    "type": "custom"
+                },
+                {
+                    "url": "https://github.com/fabpot",
+                    "type": "github"
+                },
+                {
+                    "url": "https://github.com/nicolas-grekas",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2025-07-08T02:45:35+00:00"
+        },
+        {
+            "name": "symfony/service-contracts",
+            "version": "v3.6.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/service-contracts.git",
+                "reference": "45112560a3ba2d715666a509a0bc9521d10b6c43"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/service-contracts/zipball/45112560a3ba2d715666a509a0bc9521d10b6c43",
+                "reference": "45112560a3ba2d715666a509a0bc9521d10b6c43",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.1",
+                "psr/container": "^1.1|^2.0",
+                "symfony/deprecation-contracts": "^2.5|^3"
+            },
+            "conflict": {
+                "ext-psr": "<1.1|>=2"
+            },
+            "type": "library",
+            "extra": {
+                "thanks": {
+                    "url": "https://github.com/symfony/contracts",
+                    "name": "symfony/contracts"
+                },
+                "branch-alias": {
+                    "dev-main": "3.6-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Contracts\\Service\\": ""
+                },
+                "exclude-from-classmap": [
+                    "/Test/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nicolas Grekas",
+                    "email": "p@tchwork.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Generic abstractions related to writing services",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "abstractions",
+                "contracts",
+                "decoupling",
+                "interfaces",
+                "interoperability",
+                "standards"
+            ],
+            "support": {
+                "source": "https://github.com/symfony/service-contracts/tree/v3.6.1"
+            },
+            "funding": [
+                {
+                    "url": "https://symfony.com/sponsor",
+                    "type": "custom"
+                },
+                {
+                    "url": "https://github.com/fabpot",
+                    "type": "github"
+                },
+                {
+                    "url": "https://github.com/nicolas-grekas",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2025-07-15T11:30:57+00:00"
+        },
         {
             "name": "twig/twig",
             "version": "v3.22.2",
@@ -324,7 +975,9 @@
     "packages-dev": [],
     "aliases": [],
     "minimum-stability": "stable",
-    "stability-flags": {},
+    "stability-flags": {
+        "magdev/wc-licensed-product-client": 20
+    },
     "prefer-stable": true,
     "prefer-lowest": false,
     "platform": {

openapi.json

@@ -2,8 +2,8 @@
   "openapi": "3.1.0",
   "info": {
     "title": "WooCommerce Licensed Product API",
-    "description": "REST API for validating and managing software licenses bound to domains. This API allows external applications to validate license keys, check license status, and activate licenses on specific domains.",
+    "description": "REST API for validating and managing software licenses bound to domains. This API allows external applications to validate license keys, check license status, and activate licenses on specific domains.\n\n## Response Signing (Optional)\n\nWhen the server is configured with `WC_LICENSE_SERVER_SECRET`, all API responses include cryptographic signatures for tamper protection:\n\n- `X-License-Signature`: HMAC-SHA256 signature of the response\n- `X-License-Timestamp`: Unix timestamp when the response was generated\n\nSignature verification prevents man-in-the-middle attacks and ensures response integrity. Use the `magdev/wc-licensed-product-client` library's `SecureLicenseClient` class to automatically verify signatures.",
-    "version": "0.0.7",
+    "version": "0.3.2",
     "contact": {
       "name": "Marco Graetsch",
       "url": "https://src.bundespruefstelle.ch/magdev",
@@ -55,6 +55,14 @@
         "responses": {
           "200": {
             "description": "License is valid for the specified domain",
+            "headers": {
+              "X-License-Signature": {
+                "$ref": "#/components/headers/X-License-Signature"
+              },
+              "X-License-Timestamp": {
+                "$ref": "#/components/headers/X-License-Timestamp"
+              }
+            },
             "content": {
               "application/json": {
                 "schema": {
@@ -156,6 +164,14 @@
         "responses": {
           "200": {
             "description": "License status retrieved successfully",
+            "headers": {
+              "X-License-Signature": {
+                "$ref": "#/components/headers/X-License-Signature"
+              },
+              "X-License-Timestamp": {
+                "$ref": "#/components/headers/X-License-Timestamp"
+              }
+            },
             "content": {
               "application/json": {
                 "schema": {
@@ -221,6 +237,14 @@
         "responses": {
           "200": {
             "description": "License activated successfully or already activated",
+            "headers": {
+              "X-License-Signature": {
+                "$ref": "#/components/headers/X-License-Signature"
+              },
+              "X-License-Timestamp": {
+                "$ref": "#/components/headers/X-License-Timestamp"
+              }
+            },
             "content": {
               "application/json": {
                 "schema": {
@@ -519,6 +543,26 @@
           }
         }
       }
+    },
+    "headers": {
+      "X-License-Signature": {
+        "description": "HMAC-SHA256 signature of the response body for tamper protection. Only present when server is configured with WC_LICENSE_SERVER_SECRET. Signature format: hex-encoded HMAC-SHA256 of (timestamp + ':' + canonical_json_body) using a per-license derived key.",
+        "schema": {
+          "type": "string",
+          "pattern": "^[a-f0-9]{64}$",
+          "example": "a1b2c3d4e5f6789012345678901234567890abcdef1234567890abcdef123456"
+        },
+        "required": false
+      },
+      "X-License-Timestamp": {
+        "description": "Unix timestamp when the response was generated. Used together with X-License-Signature to prevent replay attacks. Only present when server is configured with WC_LICENSE_SERVER_SECRET.",
+        "schema": {
+          "type": "string",
+          "pattern": "^[0-9]+$",
+          "example": "1737550000"
+        },
+        "required": false
+      }
     }
   },
   "tags": [

releases/wc-licensed-product-0.3.3.sha256

@@ -0,0 +1 @@
+a06d29eabc2da08613ae13874ed152b8ea9363b8284a2e9bdda414e32777558c  wc-licensed-product-0.3.3.zip

src/Admin/AdminController.php

@@ -61,6 +61,9 @@ final class AdminController
         add_action('wp_ajax_wclp_update_license_expiry', [$this, 'handleAjaxExpiryUpdate']);
         add_action('wp_ajax_wclp_update_license_domain', [$this, 'handleAjaxDomainUpdate']);
         add_action('wp_ajax_wclp_revoke_license', [$this, 'handleAjaxRevoke']);
+
+        // AJAX handler for license testing
+        add_action('wp_ajax_wclp_test_license', [$this, 'handleAjaxTestLicense']);
     }
 
     /**
@@ -355,6 +358,30 @@ final class AdminController
         }
     }
 
+    /**
+     * Handle AJAX license test - validates license against the API
+     */
+    public function handleAjaxTestLicense(): void
+    {
+        check_ajax_referer('wclp_inline_edit', 'nonce');
+
+        if (!current_user_can('manage_woocommerce')) {
+            wp_send_json_error(['message' => __('Permission denied.', 'wc-licensed-product')], 403);
+        }
+
+        $licenseKey = isset($_POST['license_key']) ? sanitize_text_field(wp_unslash($_POST['license_key'])) : '';
+        $domain = isset($_POST['domain']) ? sanitize_text_field(wp_unslash($_POST['domain'])) : '';
+
+        if (empty($licenseKey) || empty($domain)) {
+            wp_send_json_error(['message' => __('License key and domain are required.', 'wc-licensed-product')]);
+        }
+
+        // Validate the license using LicenseManager
+        $result = $this->licenseManager->validateLicense($licenseKey, $domain);
+
+        wp_send_json_success($result);
+    }
+
     /**
      * Handle admin actions (update, delete licenses)
      */
@@ -1347,7 +1374,20 @@ final class AdminController
                                     </td>
                                     <td class="license-actions">
                                         <div class="row-actions">
+                                            <span class="test">
+                                                <a href="#" class="wclp-test-license-link"
+                                                   data-license-id="<?php echo esc_attr($item['license']->getId()); ?>"
+                                                   data-license-key="<?php echo esc_attr($item['license']->getLicenseKey()); ?>"
+                                                   data-domain="<?php echo esc_attr($item['license']->getDomain()); ?>"
+                                                   title="<?php esc_attr_e('Test license against API', 'wc-licensed-product'); ?>"><?php esc_html_e('Test', 'wc-licensed-product'); ?></a> |
+                                            </span>
                                             <?php if ($item['license']->getStatus() !== License::STATUS_REVOKED): ?>
+                                                <span class="transfer">
+                                                    <a href="#" class="wclp-transfer-link"
+                                                       data-license-id="<?php echo esc_attr($item['license']->getId()); ?>"
+                                                       data-current-domain="<?php echo esc_attr($item['license']->getDomain()); ?>"
+                                                       title="<?php esc_attr_e('Transfer to new domain', 'wc-licensed-product'); ?>"><?php esc_html_e('Transfer', 'wc-licensed-product'); ?></a> |
+                                                </span>
                                                 <span class="extend">
                                                     <a href="<?php echo esc_url(wp_nonce_url(
                                                         admin_url('admin.php?page=wc-licenses&action=extend&license_id=' . $item['license']->getId() . '&days=30'),
@@ -1429,8 +1469,69 @@ final class AdminController
                 </div>
             </form>
 
+            <!-- Test License Modal -->
+            <div id="wclp-test-modal" class="wclp-modal" style="display:none;">
+                <div class="wclp-modal-content">
+                    <span class="wclp-modal-close">&times;</span>
+                    <h2><?php esc_html_e('License Validation Test', 'wc-licensed-product'); ?></h2>
+                    <div class="wclp-test-info">
+                        <table class="form-table">
+                            <tr>
+                                <th scope="row"><?php esc_html_e('License Key', 'wc-licensed-product'); ?></th>
+                                <td><code id="test-license-key"></code></td>
+                            </tr>
+                            <tr>
+                                <th scope="row"><?php esc_html_e('Domain', 'wc-licensed-product'); ?></th>
+                                <td><code id="test-domain"></code></td>
+                            </tr>
+                        </table>
+                    </div>
+                    <div id="wclp-test-loading" style="display:none; text-align:center; padding:20px;">
+                        <span class="spinner is-active" style="float:none;"></span>
+                        <p><?php esc_html_e('Testing license...', 'wc-licensed-product'); ?></p>
+                    </div>
+                    <div id="wclp-test-result" style="display:none;">
+                        <div id="wclp-test-result-content"></div>
+                    </div>
+                    <p class="submit">
+                        <button type="button" class="button wclp-modal-cancel"><?php esc_html_e('Close', 'wc-licensed-product'); ?></button>
+                    </p>
+                </div>
+            </div>
+
+            <!-- Transfer Modal -->
+            <div id="wclp-transfer-modal" class="wclp-modal" style="display:none;">
+                <div class="wclp-modal-content">
+                    <span class="wclp-modal-close">&times;</span>
+                    <h2><?php esc_html_e('Transfer License to New Domain', 'wc-licensed-product'); ?></h2>
+                    <form method="post" action="<?php echo esc_url(admin_url('admin.php?page=wc-licenses')); ?>">
+                        <input type="hidden" name="action" value="transfer_license">
+                        <?php wp_nonce_field('transfer_license', '_wpnonce'); ?>
+                        <input type="hidden" name="license_id" id="transfer-license-id" value="">
+                        <table class="form-table">
+                            <tr>
+                                <th scope="row"><label><?php esc_html_e('Current Domain', 'wc-licensed-product'); ?></label></th>
+                                <td><code id="transfer-current-domain"></code></td>
+                            </tr>
+                            <tr>
+                                <th scope="row"><label for="new_domain"><?php esc_html_e('New Domain', 'wc-licensed-product'); ?></label></th>
+                                <td>
+                                    <input type="text" name="new_domain" id="transfer-new-domain" class="regular-text" placeholder="example.com" required>
+                                    <p class="description"><?php esc_html_e('Enter the new domain without http:// or www.', 'wc-licensed-product'); ?></p>
+                                </td>
+                            </tr>
+                        </table>
+                        <p class="submit">
+                            <button type="submit" class="button button-primary"><?php esc_html_e('Transfer License', 'wc-licensed-product'); ?></button>
+                            <button type="button" class="button wclp-modal-cancel"><?php esc_html_e('Cancel', 'wc-licensed-product'); ?></button>
+                        </p>
+                    </form>
+                </div>
+            </div>
+
             <script>
             (function($) {
+                // Checkbox select all
                 $('#cb-select-all-1, #cb-select-all-2').on('change', function() {
                     $('input[name="license_ids[]"]').prop('checked', this.checked);
                     $('#cb-select-all-1, #cb-select-all-2').prop('checked', this.checked);
@@ -1445,6 +1546,102 @@ final class AdminController
                         $('#bulk-action-selector').val(bottomAction);
                     }
                 });
+
+                // Transfer modal
+                var $transferModal = $('#wclp-transfer-modal');
+                $('.wclp-transfer-link').on('click', function(e) {
+                    e.preventDefault();
+                    var licenseId = $(this).data('license-id');
+                    var currentDomain = $(this).data('current-domain');
+                    $('#transfer-license-id').val(licenseId);
+                    $('#transfer-current-domain').text(currentDomain);
+                    $('#transfer-new-domain').val('');
+                    $transferModal.show();
+                });
+
+                // Test License modal
+                var $testModal = $('#wclp-test-modal');
+                var $testLoading = $('#wclp-test-loading');
+                var $testResult = $('#wclp-test-result');
+                var $testResultContent = $('#wclp-test-result-content');
+
+                $('.wclp-test-license-link').on('click', function(e) {
+                    e.preventDefault();
+                    var licenseKey = $(this).data('license-key');
+                    var domain = $(this).data('domain');
+
+                    $('#test-license-key').text(licenseKey);
+                    $('#test-domain').text(domain);
+                    $testLoading.show();
+                    $testResult.hide();
+                    $testModal.show();
+
+                    $.ajax({
+                        url: wclpAdmin.ajaxUrl,
+                        type: 'POST',
+                        data: {
+                            action: 'wclp_test_license',
+                            nonce: wclpAdmin.editNonce,
+                            license_key: licenseKey,
+                            domain: domain
+                        },
+                        success: function(response) {
+                            $testLoading.hide();
+                            if (response.success) {
+                                var result = response.data;
+                                var html = '';
+
+                                if (result.valid) {
+                                    html = '<div class="notice notice-success inline"><p><strong>✓ <?php echo esc_js(__('License is VALID', 'wc-licensed-product')); ?></strong></p></div>';
+                                    html += '<table class="widefat striped"><tbody>';
+                                    html += '<tr><th><?php echo esc_js(__('Product', 'wc-licensed-product')); ?></th><td>' + escapeHtml(result.product_name || '-') + '</td></tr>';
+                                    html += '<tr><th><?php echo esc_js(__('Version', 'wc-licensed-product')); ?></th><td>' + escapeHtml(result.version || '-') + '</td></tr>';
+                                    if (result.expires_at) {
+                                        html += '<tr><th><?php echo esc_js(__('Expires', 'wc-licensed-product')); ?></th><td>' + escapeHtml(result.expires_at) + '</td></tr>';
+                                    } else {
+                                        html += '<tr><th><?php echo esc_js(__('Expires', 'wc-licensed-product')); ?></th><td><?php echo esc_js(__('Lifetime', 'wc-licensed-product')); ?></td></tr>';
+                                    }
+                                    html += '</tbody></table>';
+                                } else {
+                                    html = '<div class="notice notice-error inline"><p><strong>✗ <?php echo esc_js(__('License is INVALID', 'wc-licensed-product')); ?></strong></p></div>';
+                                    html += '<table class="widefat striped"><tbody>';
+                                    html += '<tr><th><?php echo esc_js(__('Error Code', 'wc-licensed-product')); ?></th><td><code>' + escapeHtml(result.error || 'unknown') + '</code></td></tr>';
+                                    html += '<tr><th><?php echo esc_js(__('Message', 'wc-licensed-product')); ?></th><td>' + escapeHtml(result.message || '-') + '</td></tr>';
+                                    html += '</tbody></table>';
+                                }
+
+                                $testResultContent.html(html);
+                                $testResult.show();
+                            } else {
+                                $testResultContent.html('<div class="notice notice-error inline"><p>' + escapeHtml(response.data.message || 'Error') + '</p></div>');
+                                $testResult.show();
+                            }
+                        },
+                        error: function() {
+                            $testLoading.hide();
+                            $testResultContent.html('<div class="notice notice-error inline"><p><?php echo esc_js(__('Failed to test license. Please try again.', 'wc-licensed-product')); ?></p></div>');
+                            $testResult.show();
+                        }
+                    });
+                });
+
+                // Close modals
+                $('.wclp-modal-close, .wclp-modal-cancel').on('click', function() {
+                    $(this).closest('.wclp-modal').hide();
+                });
+
+                $(window).on('click', function(e) {
+                    if ($(e.target).hasClass('wclp-modal')) {
+                        $(e.target).hide();
+                    }
+                });
+
+                function escapeHtml(text) {
+                    if (!text) return '';
+                    var div = document.createElement('div');
+                    div.textContent = text;
+                    return div.innerHTML;
+                }
             })(jQuery);
             </script>
         </div>

src/Admin/SettingsController.php

@@ -9,6 +9,8 @@ declare(strict_types=1);
 
 namespace Jeremias\WcLicensedProduct\Admin;
 
+use Jeremias\WcLicensedProduct\License\PluginLicenseChecker;
+
 /**
  * Handles WooCommerce settings tab for license defaults
  */
@@ -19,6 +21,11 @@ final class SettingsController
      */
     public const OPTION_NAME = 'wc_licensed_product_settings';
 
+    /**
+     * Tab ID
+     */
+    private const TAB_ID = 'licensed_product';
+
     /**
      * Constructor
      */
@@ -33,8 +40,10 @@ final class SettingsController
     private function registerHooks(): void
     {
         add_filter('woocommerce_settings_tabs_array', [$this, 'addSettingsTab'], 50);
-        add_action('woocommerce_settings_tabs_licensed_product', [$this, 'renderSettingsTab']);
+        add_action('woocommerce_sections_' . self::TAB_ID, [$this, 'outputSections']);
-        add_action('woocommerce_update_options_licensed_product', [$this, 'saveSettings']);
+        add_action('woocommerce_settings_' . self::TAB_ID, [$this, 'renderSettingsTab']);
+        add_action('woocommerce_update_options_' . self::TAB_ID, [$this, 'saveSettings']);
+        add_action('wp_ajax_wclp_verify_plugin_license', [$this, 'handleVerifyLicense']);
     }
 
     /**
@@ -42,14 +51,119 @@ final class SettingsController
      */
     public function addSettingsTab(array $tabs): array
     {
-        $tabs['licensed_product'] = __('Licensed Products', 'wc-licensed-product');
+        $tabs[self::TAB_ID] = __('Licensed Products', 'wc-licensed-product');
         return $tabs;
     }
 
     /**
-     * Get settings fields
+     * Get available sections
+     */
+    public function getSections(): array
+    {
+        return [
+            '' => __('Plugin License', 'wc-licensed-product'),
+            'defaults' => __('Default Settings', 'wc-licensed-product'),
+            'notifications' => __('Notifications', 'wc-licensed-product'),
+        ];
+    }
+
+    /**
+     * Get current section from URL
+     */
+    private function getCurrentSection(): string
+    {
+        // phpcs:ignore WordPress.Security.NonceVerification.Recommended
+        return isset($_GET['section']) ? sanitize_title(wp_unslash($_GET['section'])) : '';
+    }
+
+    /**
+     * Output sections navigation (sub-tabs)
+     */
+    public function outputSections(): void
+    {
+        $sections = $this->getSections();
+
+        if (empty($sections) || count($sections) <= 1) {
+            return;
+        }
+
+        $currentSection = $this->getCurrentSection();
+
+        echo '<ul class="subsubsub">';
+
+        $arrayKeys = array_keys($sections);
+
+        foreach ($sections as $id => $label) {
+            $url = admin_url('admin.php?page=wc-settings&tab=' . self::TAB_ID . '&section=' . sanitize_title($id));
+            $class = ($currentSection === $id) ? 'current' : '';
+            $separator = (end($arrayKeys) === $id) ? '' : ' | ';
+
+            echo '<li><a href="' . esc_url($url) . '" class="' . esc_attr($class) . '">' . esc_html($label) . '</a>' . $separator . '</li>';
+        }
+
+        echo '</ul><br class="clear" />';
+    }
+
+    /**
+     * Get settings fields for the current section
      */
     public function getSettingsFields(): array
+    {
+        $currentSection = $this->getCurrentSection();
+
+        return match ($currentSection) {
+            'defaults' => $this->getDefaultsSettings(),
+            'notifications' => $this->getNotificationsSettings(),
+            default => $this->getPluginLicenseSettings(),
+        };
+    }
+
+    /**
+     * Get plugin license settings (default section)
+     */
+    private function getPluginLicenseSettings(): array
+    {
+        return [
+            'plugin_license_section_title' => [
+                'name' => __('Plugin License', 'wc-licensed-product'),
+                'type' => 'title',
+                'desc' => __('Configure the license for this plugin. A valid license is required for frontend features to work.', 'wc-licensed-product'),
+                'id' => 'wc_licensed_product_section_plugin_license',
+            ],
+            'plugin_license_server_url' => [
+                'name' => __('License Server URL', 'wc-licensed-product'),
+                'type' => 'url',
+                'desc' => __('The URL of the license server (e.g., https://shop.example.com).', 'wc-licensed-product'),
+                'id' => 'wc_licensed_product_plugin_license_server_url',
+                'default' => '',
+                'placeholder' => 'https://shop.example.com',
+            ],
+            'plugin_license_key' => [
+                'name' => __('License Key', 'wc-licensed-product'),
+                'type' => 'text',
+                'desc' => __('Your license key in XXXX-XXXX-XXXX-XXXX format.', 'wc-licensed-product'),
+                'id' => 'wc_licensed_product_plugin_license_key',
+                'default' => '',
+                'placeholder' => 'XXXX-XXXX-XXXX-XXXX',
+            ],
+            'plugin_license_server_secret' => [
+                'name' => __('Server Secret (Optional)', 'wc-licensed-product'),
+                'type' => 'password',
+                'desc' => __('If the license server uses signed responses, enter the shared secret here for enhanced security.', 'wc-licensed-product'),
+                'id' => 'wc_licensed_product_plugin_license_server_secret',
+                'default' => '',
+            ],
+            'plugin_license_section_end' => [
+                'type' => 'sectionend',
+                'id' => 'wc_licensed_product_section_plugin_license_end',
+            ],
+        ];
+    }
+
+    /**
+     * Get default license settings
+     */
+    private function getDefaultsSettings(): array
     {
         return [
             'section_title' => [
@@ -92,7 +206,15 @@ final class SettingsController
                 'type' => 'sectionend',
                 'id' => 'wc_licensed_product_section_defaults_end',
             ],
-            // Email settings section
+        ];
+    }
+
+    /**
+     * Get notifications settings
+     */
+    private function getNotificationsSettings(): array
+    {
+        return [
             'email_section_title' => [
                 'name' => __('Expiration Warning Schedule', 'wc-licensed-product'),
                 'type' => 'title',
@@ -138,9 +260,96 @@ final class SettingsController
      */
     public function renderSettingsTab(): void
     {
+        $currentSection = $this->getCurrentSection();
+
+        // Only show license status on the plugin license section
+        if ($currentSection === '') {
+            $this->renderLicenseStatus();
+        }
+
         woocommerce_admin_fields($this->getSettingsFields());
     }
 
+    /**
+     * Render license status notice
+     */
+    private function renderLicenseStatus(): void
+    {
+        $checker = PluginLicenseChecker::getInstance();
+
+        if ($checker->isLocalhost()) {
+            echo '<div class="notice notice-info inline"><p>';
+            echo '<span class="dashicons dashicons-info" style="color: #00a0d2;"></span> ';
+            echo esc_html__('Running on localhost - license validation bypassed.', 'wc-licensed-product');
+            echo '</p></div>';
+            return;
+        }
+
+        if ($checker->isLicenseValid()) {
+            echo '<div class="notice notice-success inline"><p>';
+            echo '<span class="dashicons dashicons-yes-alt" style="color: #46b450;"></span> ';
+            echo esc_html__('License is valid and active.', 'wc-licensed-product');
+            echo '</p></div>';
+        } else {
+            $error = $checker->getLastError();
+            echo '<div class="notice notice-error inline"><p>';
+            echo '<span class="dashicons dashicons-warning" style="color: #dc3232;"></span> ';
+            echo esc_html__('License is not valid. Frontend features are disabled.', 'wc-licensed-product');
+            if ($error) {
+                echo '<br><small>' . esc_html($error) . '</small>';
+            }
+            echo '</p></div>';
+        }
+
+        // Add verify button
+        $nonce = wp_create_nonce('wclp_verify_license');
+        echo '<p>';
+        echo '<button type="button" class="button" id="wclp-verify-license" data-nonce="' . esc_attr($nonce) . '">';
+        echo esc_html__('Verify License', 'wc-licensed-product');
+        echo '</button>';
+        echo '<span id="wclp-verify-result" style="margin-left: 10px;"></span>';
+        echo '</p>';
+
+        // Inline script for verify button
+        ?>
+        <script type="text/javascript">
+        jQuery(function($) {
+            $('#wclp-verify-license').on('click', function() {
+                var $btn = $(this);
+                var $result = $('#wclp-verify-result');
+                var nonce = $btn.data('nonce');
+
+                $btn.prop('disabled', true).text('<?php echo esc_js(__('Verifying...', 'wc-licensed-product')); ?>');
+                $result.text('');
+
+                $.ajax({
+                    url: ajaxurl,
+                    type: 'POST',
+                    data: {
+                        action: 'wclp_verify_plugin_license',
+                        nonce: nonce
+                    },
+                    success: function(response) {
+                        if (response.success) {
+                            $result.html('<span style="color: #46b450;">' + response.data.message + '</span>');
+                            location.reload();
+                        } else {
+                            $result.html('<span style="color: #dc3232;">' + response.data.message + '</span>');
+                        }
+                    },
+                    error: function() {
+                        $result.html('<span style="color: #dc3232;"><?php echo esc_js(__('Request failed.', 'wc-licensed-product')); ?></span>');
+                    },
+                    complete: function() {
+                        $btn.prop('disabled', false).text('<?php echo esc_js(__('Verify License', 'wc-licensed-product')); ?>');
+                    }
+                });
+            });
+        });
+        </script>
+        <?php
+    }
+
     /**
      * Save settings
      */
@@ -210,4 +419,55 @@ final class SettingsController
         $value = get_option('wc_licensed_product_expiration_warning_days_second', 1);
         return max(0, (int) $value);
     }
+
+    /**
+     * Get plugin license server URL
+     */
+    public static function getPluginLicenseServerUrl(): string
+    {
+        return (string) get_option('wc_licensed_product_plugin_license_server_url', '');
+    }
+
+    /**
+     * Get plugin license key
+     */
+    public static function getPluginLicenseKey(): string
+    {
+        return (string) get_option('wc_licensed_product_plugin_license_key', '');
+    }
+
+    /**
+     * Get plugin license server secret
+     */
+    public static function getPluginLicenseServerSecret(): ?string
+    {
+        $secret = get_option('wc_licensed_product_plugin_license_server_secret', '');
+        return !empty($secret) ? (string) $secret : null;
+    }
+
+    /**
+     * Handle AJAX verify license request
+     */
+    public function handleVerifyLicense(): void
+    {
+        if (!check_ajax_referer('wclp_verify_license', 'nonce', false)) {
+            wp_send_json_error(['message' => __('Security check failed.', 'wc-licensed-product')], 403);
+        }
+
+        if (!current_user_can('manage_woocommerce')) {
+            wp_send_json_error(['message' => __('Insufficient permissions.', 'wc-licensed-product')], 403);
+        }
+
+        $checker = PluginLicenseChecker::getInstance();
+        $checker->clearCache();
+
+        $valid = $checker->validateLicense(true);
+
+        if ($valid) {
+            wp_send_json_success(['message' => __('License verified successfully!', 'wc-licensed-product')]);
+        } else {
+            $error = $checker->getLastError() ?: __('License validation failed.', 'wc-licensed-product');
+            wp_send_json_error(['message' => $error]);
+        }
+    }
 }

src/Admin/VersionAdminController.php

@@ -157,12 +157,14 @@ final class VersionAdminController
                                     $filename = $version->getDownloadFilename();
                                     if ($effectiveUrl):
                                     ?>
+                                        <span class="version-download-link">
                                             <a href="<?php echo esc_url($effectiveUrl); ?>" target="_blank">
                                                 <?php echo esc_html($filename ?: wp_basename($effectiveUrl)); ?>
                                             </a>
                                             <?php if ($version->getAttachmentId()): ?>
                                                 <span class="dashicons dashicons-media-archive" title="<?php esc_attr_e('Uploaded file', 'wc-licensed-product'); ?>"></span>
                                             <?php endif; ?>
+                                        </span>
                                     <?php else: ?>
                                         <em><?php esc_html_e('No download file', 'wc-licensed-product'); ?></em>
                                     <?php endif; ?>
@@ -359,7 +361,7 @@ final class VersionAdminController
             wp_send_json_error(['message' => __('Version ID is required.', 'wc-licensed-product')]);
         }
 
-        $result = $this->versionManager->updateVersion($versionId, null, null, !$currentlyActive);
+        $result = $this->versionManager->updateVersion($versionId, null, !$currentlyActive, null);
 
         if (!$result) {
             wp_send_json_error(['message' => __('Failed to update version.', 'wc-licensed-product')]);
@@ -386,12 +388,14 @@ final class VersionAdminController
                 $filename = $version->getDownloadFilename();
                 if ($effectiveUrl):
                 ?>
+                    <span class="version-download-link">
                         <a href="<?php echo esc_url($effectiveUrl); ?>" target="_blank">
                             <?php echo esc_html($filename ?: wp_basename($effectiveUrl)); ?>
                         </a>
                         <?php if ($version->getAttachmentId()): ?>
                             <span class="dashicons dashicons-media-archive" title="<?php esc_attr_e('Uploaded file', 'wc-licensed-product'); ?>"></span>
                         <?php endif; ?>
+                    </span>
                 <?php else: ?>
                     <em><?php esc_html_e('No download file', 'wc-licensed-product'); ?></em>
                 <?php endif; ?>

src/License/PluginLicenseChecker.php

@@ -0,0 +1,287 @@
+<?php
+/**
+ * Plugin License Checker
+ *
+ * Validates the plugin's own license against a remote server.
+ *
+ * @package Jeremias\WcLicensedProduct\License
+ */
+
+declare(strict_types=1);
+
+namespace Jeremias\WcLicensedProduct\License;
+
+use Magdev\WcLicensedProductClient\LicenseClient;
+use Magdev\WcLicensedProductClient\LicenseClientInterface;
+use Magdev\WcLicensedProductClient\SecureLicenseClient;
+use Magdev\WcLicensedProductClient\Exception\LicenseException;
+use Symfony\Component\HttpClient\HttpClient;
+
+/**
+ * Handles validation of this plugin's license
+ */
+final class PluginLicenseChecker
+{
+    /**
+     * Cache key for license validation result
+     */
+    private const CACHE_KEY = 'wclp_plugin_license_valid';
+
+    /**
+     * Cache TTL for successful validation (1 hour)
+     */
+    private const CACHE_TTL = 3600;
+
+    /**
+     * Cache key for error messages
+     */
+    private const ERROR_CACHE_KEY = 'wclp_plugin_license_error';
+
+    /**
+     * Cache TTL for errors (5 minutes)
+     */
+    private const ERROR_CACHE_TTL = 300;
+
+    /**
+     * Singleton instance
+     */
+    private static ?self $instance = null;
+
+    /**
+     * Cached localhost check result
+     */
+    private ?bool $isLocalhostCached = null;
+
+    /**
+     * Get singleton instance
+     */
+    public static function getInstance(): self
+    {
+        if (self::$instance === null) {
+            self::$instance = new self();
+        }
+
+        return self::$instance;
+    }
+
+    /**
+     * Private constructor for singleton
+     */
+    private function __construct()
+    {
+        // Private constructor
+    }
+
+    /**
+     * Check if the plugin license is valid
+     *
+     * Returns cached result if available, otherwise validates against server.
+     */
+    public function isLicenseValid(): bool
+    {
+        // Always valid on localhost
+        if ($this->isLocalhost()) {
+            return true;
+        }
+
+        // Check cache first
+        $cached = get_transient(self::CACHE_KEY);
+        if ($cached !== false) {
+            return (bool) $cached;
+        }
+
+        // Validate against server
+        return $this->validateLicense();
+    }
+
+    /**
+     * Validate license against the server
+     *
+     * @param bool $forceRefresh Force refresh even if cached
+     * @return bool True if license is valid
+     */
+    public function validateLicense(bool $forceRefresh = false): bool
+    {
+        // Always valid on localhost
+        if ($this->isLocalhost()) {
+            return true;
+        }
+
+        // Check settings are configured
+        $serverUrl = $this->getLicenseServerUrl();
+        $licenseKey = $this->getLicenseKey();
+
+        if (empty($serverUrl) || empty($licenseKey)) {
+            set_transient(
+                self::ERROR_CACHE_KEY,
+                __('License settings not configured.', 'wc-licensed-product'),
+                self::ERROR_CACHE_TTL
+            );
+            return false;
+        }
+
+        // Check cache unless force refresh
+        if (!$forceRefresh) {
+            $cached = get_transient(self::CACHE_KEY);
+            if ($cached !== false) {
+                return (bool) $cached;
+            }
+        }
+
+        try {
+            $client = $this->createLicenseClient();
+            $domain = $this->getCurrentDomain();
+
+            // Validate the license
+            $client->validate($licenseKey, $domain);
+
+            // Valid license - cache success
+            set_transient(self::CACHE_KEY, 1, self::CACHE_TTL);
+            delete_transient(self::ERROR_CACHE_KEY);
+
+            return true;
+        } catch (LicenseException $e) {
+            // License-specific error (invalid, expired, revoked, etc.)
+            set_transient(self::CACHE_KEY, 0, self::CACHE_TTL);
+            set_transient(self::ERROR_CACHE_KEY, $e->getMessage(), self::ERROR_CACHE_TTL);
+
+            return false;
+        } catch (\Throwable $e) {
+            // Network/server error - use shorter cache to allow retry
+            set_transient(
+                self::ERROR_CACHE_KEY,
+                __('Could not connect to license server.', 'wc-licensed-product') . ' ' . $e->getMessage(),
+                self::ERROR_CACHE_TTL
+            );
+
+            // Don't cache validation failure on network errors - allow retry on next page load
+            return false;
+        }
+    }
+
+    /**
+     * Get the last error message
+     */
+    public function getLastError(): ?string
+    {
+        $error = get_transient(self::ERROR_CACHE_KEY);
+        return $error !== false ? (string) $error : null;
+    }
+
+    /**
+     * Clear the validation cache
+     */
+    public function clearCache(): void
+    {
+        delete_transient(self::CACHE_KEY);
+        delete_transient(self::ERROR_CACHE_KEY);
+        $this->isLocalhostCached = null;
+    }
+
+    /**
+     * Check if running on localhost
+     *
+     * Matches localhost, 127.0.0.1, ::1, and any port number.
+     */
+    public function isLocalhost(): bool
+    {
+        if ($this->isLocalhostCached !== null) {
+            return $this->isLocalhostCached;
+        }
+
+        $domain = $this->getCurrentDomain();
+
+        // Remove port number if present
+        $domainWithoutPort = preg_replace('/:[\d]+$/', '', $domain);
+
+        // Check for localhost variants
+        $localhostNames = ['localhost', '127.0.0.1', '::1'];
+
+        if (in_array($domainWithoutPort, $localhostNames, true)) {
+            $this->isLocalhostCached = true;
+            return true;
+        }
+
+        // Check for .localhost and .local subdomains
+        if (
+            str_ends_with($domainWithoutPort, '.localhost') ||
+            str_ends_with($domainWithoutPort, '.local')
+        ) {
+            $this->isLocalhostCached = true;
+            return true;
+        }
+
+        $this->isLocalhostCached = false;
+        return false;
+    }
+
+    /**
+     * Get the current domain from the site URL
+     */
+    private function getCurrentDomain(): string
+    {
+        $siteUrl = get_site_url();
+        $parsed = parse_url($siteUrl);
+        $host = $parsed['host'] ?? 'localhost';
+
+        // Include port if non-standard
+        if (isset($parsed['port'])) {
+            $host .= ':' . $parsed['port'];
+        }
+
+        return strtolower($host);
+    }
+
+    /**
+     * Get the license server URL from settings
+     */
+    private function getLicenseServerUrl(): string
+    {
+        return (string) get_option('wc_licensed_product_plugin_license_server_url', '');
+    }
+
+    /**
+     * Get the license key from settings
+     */
+    private function getLicenseKey(): string
+    {
+        return (string) get_option('wc_licensed_product_plugin_license_key', '');
+    }
+
+    /**
+     * Get the server secret from settings (optional)
+     */
+    private function getServerSecret(): ?string
+    {
+        $secret = get_option('wc_licensed_product_plugin_license_server_secret', '');
+        return !empty($secret) ? (string) $secret : null;
+    }
+
+    /**
+     * Create the license client instance
+     */
+    private function createLicenseClient(): LicenseClientInterface
+    {
+        $httpClient = HttpClient::create([
+            'timeout' => 10,
+            'verify_peer' => true,
+        ]);
+
+        $serverUrl = $this->getLicenseServerUrl();
+        $serverSecret = $this->getServerSecret();
+
+        // Use secure client if server secret is configured
+        if ($serverSecret !== null) {
+            return new SecureLicenseClient(
+                httpClient: $httpClient,
+                baseUrl: $serverUrl,
+                serverSecret: $serverSecret,
+            );
+        }
+
+        return new LicenseClient(
+            httpClient: $httpClient,
+            baseUrl: $serverUrl,
+        );
+    }
+}

src/Plugin.php

@@ -22,6 +22,7 @@ use Jeremias\WcLicensedProduct\Email\LicenseEmailController;
 use Jeremias\WcLicensedProduct\Frontend\AccountController;
 use Jeremias\WcLicensedProduct\Frontend\DownloadController;
 use Jeremias\WcLicensedProduct\License\LicenseManager;
+use Jeremias\WcLicensedProduct\License\PluginLicenseChecker;
 use Jeremias\WcLicensedProduct\Product\LicensedProductType;
 use Jeremias\WcLicensedProduct\Product\VersionManager;
 use Twig\Environment;
@@ -119,13 +120,23 @@ final class Plugin
         $this->licenseManager = new LicenseManager();
         $this->versionManager = new VersionManager();
 
-        // Initialize controllers
+        // Check plugin license
+        $licenseChecker = PluginLicenseChecker::getInstance();
+        $isLicensed = $licenseChecker->isLicenseValid();
+
+        // Always initialize product type (needed for existing orders)
         new LicensedProductType();
+
+        // Only initialize frontend components if licensed or on localhost
+        if ($isLicensed) {
             new CheckoutController($this->licenseManager);
             new StoreApiExtension($this->licenseManager);
             $this->registerCheckoutBlocksIntegration();
             $this->downloadController = new DownloadController($this->licenseManager, $this->versionManager);
             new AccountController($this->twig, $this->licenseManager, $this->versionManager, $this->downloadController);
+        }
+
+        // Always initialize REST API and email controller
         new RestApiController($this->licenseManager);
         new LicenseEmailController($this->licenseManager);
 
@@ -134,11 +145,17 @@ final class Plugin
             (new ResponseSigner())->register();
         }
 
+        // Admin always available
         if (is_admin()) {
             new AdminController($this->twig, $this->licenseManager);
             new VersionAdminController($this->versionManager);
             new OrderLicenseController($this->licenseManager);
             new SettingsController();
+
+            // Show admin notice if unlicensed and not on localhost
+            if (!$isLicensed && !$licenseChecker->isLocalhost()) {
+                add_action('admin_notices', [$this, 'showUnlicensedNotice']);
+            }
         }
     }
 
@@ -164,6 +181,9 @@ final class Plugin
      */
     private function registerHooks(): void
     {
+        // Only register order hooks if licensed (license generation requires valid license)
+        $licenseChecker = PluginLicenseChecker::getInstance();
+        if ($licenseChecker->isLicenseValid()) {
             // Generate license on order completion (multiple hooks for compatibility)
             add_action('woocommerce_order_status_completed', [$this, 'onOrderCompleted']);
             add_action('woocommerce_order_status_processing', [$this, 'onOrderCompleted']);
@@ -171,6 +191,7 @@ final class Plugin
             // Also hook into payment complete for immediate license generation
             add_action('woocommerce_payment_complete', [$this, 'onOrderCompleted']);
         }
+    }
 
     /**
      * Handle order completion - generate licenses
@@ -221,4 +242,29 @@ final class Plugin
     {
         return $this->twig->render($template, $context);
     }
+
+    /**
+     * Show admin notice when plugin is unlicensed
+     */
+    public function showUnlicensedNotice(): void
+    {
+        $settingsUrl = admin_url('admin.php?page=wc-settings&tab=licensed_product');
+        ?>
+        <div class="notice notice-warning is-dismissible">
+            <p>
+                <strong><?php esc_html_e('WC Licensed Product', 'wc-licensed-product'); ?>:</strong>
+                <?php esc_html_e('Plugin license is not configured or invalid. Frontend features are disabled.', 'wc-licensed-product'); ?>
+                <a href="<?php echo esc_url($settingsUrl); ?>"><?php esc_html_e('Configure License', 'wc-licensed-product'); ?></a>
+            </p>
+        </div>
+        <?php
+    }
+
+    /**
+     * Get the plugin license checker instance
+     */
+    public function getLicenseChecker(): PluginLicenseChecker
+    {
+        return PluginLicenseChecker::getInstance();
+    }
 }

src/Product/LicensedProductType.php

@@ -45,6 +45,12 @@ final class LicensedProductType
 
         // Make product virtual by default
         add_filter('woocommerce_product_is_virtual', [$this, 'isVirtual'], 10, 2);
+
+        // Display current version under product title on single product page
+        add_action('woocommerce_single_product_summary', [$this, 'displayCurrentVersion'], 6);
+
+        // Enqueue frontend CSS for licensed products on single product pages
+        add_action('wp_enqueue_scripts', [$this, 'enqueueFrontendStyles']);
     }
 
     /**
@@ -235,4 +241,52 @@ final class LicensedProductType
         }
         return $isVirtual;
     }
+
+    /**
+     * Enqueue frontend styles for licensed products on single product pages
+     */
+    public function enqueueFrontendStyles(): void
+    {
+        if (!is_product()) {
+            return;
+        }
+
+        global $product;
+
+        if (!$product || !$product->is_type('licensed')) {
+            return;
+        }
+
+        wp_enqueue_style(
+            'wc-licensed-product-frontend',
+            WC_LICENSED_PRODUCT_PLUGIN_URL . 'assets/css/frontend.css',
+            [],
+            WC_LICENSED_PRODUCT_VERSION
+        );
+    }
+
+    /**
+     * Display current version under product title on single product page
+     */
+    public function displayCurrentVersion(): void
+    {
+        global $product;
+
+        if (!$product || !$product->is_type('licensed')) {
+            return;
+        }
+
+        /** @var LicensedProduct $product */
+        $version = $product->get_current_version();
+
+        if (empty($version)) {
+            return;
+        }
+
+        printf(
+            '<p class="wclp-product-version"><span class="version-label">%s</span> <span class="version-number">%s</span></p>',
+            esc_html__('Version:', 'wc-licensed-product'),
+            esc_html($version)
+        );
+    }
 }

templates/admin/licenses.html.twig

@@ -184,6 +184,13 @@
                             </td>
                             <td class="license-actions">
                                 <div class="row-actions">
+                                    <span class="test">
+                                        <a href="#" class="wclp-test-license-link"
+                                           data-license-id="{{ item.license.id }}"
+                                           data-license-key="{{ esc_attr(item.license.licenseKey) }}"
+                                           data-domain="{{ esc_attr(item.license.domain) }}"
+                                           title="{{ __('Test license against API') }}">{{ __('Test') }}</a> |
+                                    </span>
                                     {% if item.license.status != 'revoked' %}
                                         <span class="transfer">
                                             <a href="#" class="wclp-transfer-link"
@@ -272,6 +279,36 @@
     </form>
 </div>
 
+<!-- Test License Modal -->
+<div id="wclp-test-modal" class="wclp-modal" style="display:none;">
+    <div class="wclp-modal-content">
+        <span class="wclp-modal-close">&times;</span>
+        <h2>{{ __('License Validation Test') }}</h2>
+        <div class="wclp-test-info">
+            <table class="form-table">
+                <tr>
+                    <th scope="row">{{ __('License Key') }}</th>
+                    <td><code id="test-license-key"></code></td>
+                </tr>
+                <tr>
+                    <th scope="row">{{ __('Domain') }}</th>
+                    <td><code id="test-domain"></code></td>
+                </tr>
+            </table>
+        </div>
+        <div id="wclp-test-loading" style="display:none; text-align:center; padding:20px;">
+            <span class="spinner is-active" style="float:none;"></span>
+            <p>{{ __('Testing license...') }}</p>
+        </div>
+        <div id="wclp-test-result" style="display:none;">
+            <div id="wclp-test-result-content"></div>
+        </div>
+        <p class="submit">
+            <button type="button" class="button wclp-modal-cancel">{{ __('Close') }}</button>
+        </p>
+    </div>
+</div>
+
 <!-- Transfer Modal -->
 <div id="wclp-transfer-modal" class="wclp-modal" style="display:none;">
     <div class="wclp-modal-content">
@@ -349,5 +386,91 @@
             $modal.hide();
         }
     });
+
+    // Test License modal
+    var $testModal = $('#wclp-test-modal');
+    var $testLoading = $('#wclp-test-loading');
+    var $testResult = $('#wclp-test-result');
+    var $testResultContent = $('#wclp-test-result-content');
+
+    $('.wclp-test-license-link').on('click', function(e) {
+        e.preventDefault();
+        var licenseKey = $(this).data('license-key');
+        var domain = $(this).data('domain');
+
+        // Show modal with info
+        $('#test-license-key').text(licenseKey);
+        $('#test-domain').text(domain);
+        $testLoading.show();
+        $testResult.hide();
+        $testModal.show();
+
+        // Call the test endpoint
+        $.ajax({
+            url: wclpAdmin.ajaxUrl,
+            type: 'POST',
+            data: {
+                action: 'wclp_test_license',
+                nonce: wclpAdmin.editNonce,
+                license_key: licenseKey,
+                domain: domain
+            },
+            success: function(response) {
+                $testLoading.hide();
+                if (response.success) {
+                    var result = response.data;
+                    var html = '';
+
+                    if (result.valid) {
+                        html = '<div class="notice notice-success inline"><p><strong>✓ {{ __('License is VALID') }}</strong></p></div>';
+                        html += '<table class="widefat striped"><tbody>';
+                        html += '<tr><th>{{ __('Product') }}</th><td>' + escapeHtml(result.product_name || '-') + '</td></tr>';
+                        html += '<tr><th>{{ __('Version') }}</th><td>' + escapeHtml(result.version || '-') + '</td></tr>';
+                        if (result.expires_at) {
+                            html += '<tr><th>{{ __('Expires') }}</th><td>' + escapeHtml(result.expires_at) + '</td></tr>';
+                        } else {
+                            html += '<tr><th>{{ __('Expires') }}</th><td>{{ __('Lifetime') }}</td></tr>';
+                        }
+                        html += '</tbody></table>';
+                    } else {
+                        html = '<div class="notice notice-error inline"><p><strong>✗ {{ __('License is INVALID') }}</strong></p></div>';
+                        html += '<table class="widefat striped"><tbody>';
+                        html += '<tr><th>{{ __('Error Code') }}</th><td><code>' + escapeHtml(result.error || 'unknown') + '</code></td></tr>';
+                        html += '<tr><th>{{ __('Message') }}</th><td>' + escapeHtml(result.message || '-') + '</td></tr>';
+                        html += '</tbody></table>';
+                    }
+
+                    $testResultContent.html(html);
+                    $testResult.show();
+                } else {
+                    $testResultContent.html('<div class="notice notice-error inline"><p>' + escapeHtml(response.data.message || 'Error') + '</p></div>');
+                    $testResult.show();
+                }
+            },
+            error: function() {
+                $testLoading.hide();
+                $testResultContent.html('<div class="notice notice-error inline"><p>{{ __('Failed to test license. Please try again.') }}</p></div>');
+                $testResult.show();
+            }
+        });
+    });
+
+    // Close test modal
+    $testModal.find('.wclp-modal-close, .wclp-modal-cancel').on('click', function() {
+        $testModal.hide();
+    });
+
+    $(window).on('click', function(e) {
+        if ($(e.target).is($testModal)) {
+            $testModal.hide();
+        }
+    });
+
+    function escapeHtml(text) {
+        if (!text) return '';
+        var div = document.createElement('div');
+        div.textContent = text;
+        return div.innerHTML;
+    }
 })(jQuery);
 </script>

wc-licensed-product.php

@@ -3,7 +3,7 @@
  * Plugin Name: WooCommerce Licensed Product
  * Plugin URI: https://src.bundespruefstelle.ch/magdev/wc-licensed-product
  * Description: WooCommerce plugin to sell software products using license keys with domain-based validation.
- * Version: 0.2.2
+ * Version: 0.3.4
  * Author: Marco Graetsch
  * Author URI: https://src.bundespruefstelle.ch/magdev
  * License: GPL-2.0-or-later
@@ -28,7 +28,7 @@ if (!defined('ABSPATH')) {
 }
 
 // Plugin constants
-define('WC_LICENSED_PRODUCT_VERSION', '0.2.2');
+define('WC_LICENSED_PRODUCT_VERSION', '0.3.4');
 define('WC_LICENSED_PRODUCT_PLUGIN_FILE', __FILE__);
 define('WC_LICENSED_PRODUCT_PLUGIN_DIR', plugin_dir_path(__FILE__));
 define('WC_LICENSED_PRODUCT_PLUGIN_URL', plugin_dir_url(__FILE__));