wc-licensed-product/CLAUDE.md

# WooCommerce Plugin for licensed Products

**Author:** Marco Graetsch
**Author URL:** <https://src.bundespruefstelle.ch/magdev>
**Author Email:** <magdev3.0@gmail.com>
**Repository URL:** <https://src.bundespruefstelle.ch/magdev/wc-licensed-product>
**Issues URL:** <https://src.bundespruefstelle.ch/magdev/wc-licensed-product/issues>

## Project Overview

This plugin adds a new product type named `licensed` to sell software products using license keys. It implements an endpoint to check valid licenses against the WooCommerce payment database. License keys are generated are bounded to a specific domain, which must be defined within the checkout process, and will be available as soon as an order is marked as paid. License keys can optionally be bound to major software versions. Customer can view their purchased license keys in their customer profile.

### Features

- Add a new product type named `licensed`
- Generate license keys based on purchased releases, bounded to a specific domain, if the related payment is marked as completed

#### Frontend

- Customers can view their purchased licenses in the customer area

#### Administration

- Add CRUD for license keys
- Manage different versions of the same licensed product

### Key Fact: 100% AI-Generated

This project is proudly **"vibe-coded"** using Claude.AI - the entire codebase was created through AI assistance.

## Temporary Roadmap

**Note for AI Assistants:** Clean this section after the specific features are done or new releases are made. Effective changes are tracked in `CHANGELOG.md`. Do not add completed versions here - document them in the Session History section at the end of this file.

### Known Bugs

No known bugs at the moment.

## Technical Stack

- **Language:** PHP 8.3.x
- **Framework:** Latest WordPress Plugin API
- **E-commerce:** WooCommerce 10.0+
- **Template Engine:** Twig 3.0 (via Composer)
- **Wordpress Base Theme** twentytwentyfive
- **Frontend:** Vanilla JavaScript
- **Styling:** Custom CSS
- **Dependency Management:** Composer
- **Internationalization:** WordPress i18n (.pot/.po/.mo files)
- **Canonical Plugin Name:** `wc-licensed-product`

### Security Best Practices

- All user inputs are sanitized (integers for quantities/prices)
- Nonce verification on form submissions
- Output escaping in templates (`esc_attr`, `esc_html`, `esc_js`)
- Direct file access prevention via `ABSPATH` check

### Translation Ready

All user-facing strings use:

```php
__('Text to translate', 'wc-licensed-product')
_e('Text to translate', 'wc-licensed-product')
```

Text domain: `wc-licensed-product`

#### Translation Template

- Base `.pot` file created: `languages/wc-licensed-product.pot`
- Ready for translation to any locale
- All translatable strings properly marked with text domain

#### Available Translations

- `en_US` - English (United States) [base language - .pot template]
- `de_CH` - German (Switzerland, formal)

To compile translations to .mo files for production:

```bash
for po in languages/*.po; do msgfmt -o "${po%.po}.mo" "$po"; done
```

### Create releases

- The `vendor/` directory MUST be included in releases (Dependencies required for runtime)
- **Don't create any release files until version 0.1.x and up!**
- **CRITICAL**: Build `vendor/` for the MINIMUM supported PHP version, not the development version
  - Use `composer config platform.php 8.3.0` before building release packages
  - Run `composer update --no-dev --optimize-autoloader` to rebuild dependencies
- **CRITICAL**: WordPress requires plugins in a subdirectory structure
  - Run zip from the `plugins/` parent directory, NOT from within the plugin directory
  - Package must extract to `wc-licensed-product/` subdirectory with main file at `wc-licensed-product/wc-licensed-product.php`
  - Correct command: `cd /wp-content/plugins/ && zip -r wc-licensed-product/releases/wc-licensed-product-x.x.x.zip wc-licensed-product ...`
  - Wrong: Running zip from inside the plugin directory creates files at root level
- **CRITICAL**: Exclude symlinks explicitly - zip follows symlinks by default
  - Always use `-x "wc-licensed-product/wp-core" -x "wc-licensed-product/wp-core/*" -x "wc-licensed-product/wp-plugins" -x "wc-licensed-product/wp-plugins/*"` to exclude development symlinks
  - Otherwise the entire linked directory contents will be included in the package
- Exclusion patterns must match the relative path structure used in zip command
- Always verify the package structure with `unzip -l` before distribution
  - Check all files are prefixed with `wc-licensed-product/`
  - Verify main file is at `wc-licensed-product/wc-licensed-product.php`
  - Check for duplicate entries (indicates multiple builds in same archive)
- Test installation on the minimum supported PHP version before final deployment
- Releases are stored in `releases/` including checksums
- Track release changes in a single `CHANGELOG.md` file
- Bump the version number to either bugfix release versions or on new features minor release versions
- **CRITICAL**: WordPress reads version from TWO places - BOTH must be updated:
  1. Plugin header comment `Version: x.x.x` (line ~6 in wc-licensed-product.php) - WordPress uses THIS for admin display
  2. PHP constant `WC_LICENSED_PRODUCT_VERSION` (line ~28) - Used internally by the plugin
  - If only the constant is updated, WordPress will show the old version in Plugins list

**Important Git Notes:**

- Default branch while development is `dev`
- Create releases from branch `main` after merging branch `dev`
- Tags should use format `vX.X.X` (e.g., `v1.1.22`), start with v0.1.0
- Use annotated tags (`-a`) not lightweight tags
- Commit messages should follow the established format with Claude Code attribution
- `.claude/settings.local.json` changes are typically local-only (stash before rebasing)

#### What Gets Released

- All plugin source files
- Compiled vendor dependencies
- Translation files (.mo compiled from .po)
- Assets (CSS, JS)
- Documentation (README, CHANGELOG, etc.)

#### What's Excluded

- Git metadata (`.git/`)
- Development files (`.vscode/`, `.claude/`, `CLAUDE.md`, `wp-core`, `wp-plugins`)
- Logs and cache files
- Previous releases
- `composer.lock` (but `vendor/` is included)

---

**For AI Assistants:**

When starting a new session on this project:

1. Read this CLAUDE.md file first
2. Semantic versioning follows the `MAJOR.MINOR.BUGFIX` pattern
3. Check git log for recent changes
4. Verify you're on the `dev` branch before making changes
5. Run `composer install` if vendor/ is missing
6. Test changes before committing
7. Follow commit message format with Claude Code attribution
8. Update this session history section with learnings
9. Never commit backup files (`*.po~`, `*.bak`, etc.) - check `git status` before committing
10. Follow markdown linting rules (see below)

Always refer to this document when starting work on this project.

### Markdown Linting Rules

When editing CLAUDE.md or other markdown files, follow these rules to avoid linting errors:

1. **MD031 - Blank lines around fenced code blocks**: Always add a blank line before and after fenced code blocks, even when they follow list items. Example of correct format:

   - **Item label**:

     (blank line here)
     \`\`\`php
     code example
     \`\`\`
     (blank line here)

2. **MD056 - Table column count**: Table separators must have matching column counts and proper spacing. Use consistent dash lengths that match column header widths.

3. **MD009 - No trailing spaces**: Remove trailing whitespace from lines

4. **MD012 - No multiple consecutive blank lines**: Use only single blank lines between sections

5. **MD040 - Fenced code blocks should have a language specified**: Always add a language identifier to code blocks (e.g., `txt`, `bash`, `php`). For shortcode examples, use `txt`.

6. **MD032 - Lists should be surrounded by blank lines**: Add a blank line before AND after list blocks, including after bold labels like `**Attributes:**`.

7. **MD034 - Bare URLs**: Wrap URLs in angle brackets (e.g., `<https://example.com>`) or use markdown link syntax `[text](url)`.

8. **Author section formatting**: Use a heading (`### Name`) instead of bold (`**Name**`) for the author name to maintain consistent document structure.

## Project Architecture

### Directory Structure

```txt
wc-licensed-product/
├── assets/
│   └── css/           # Frontend and admin stylesheets
├── languages/         # Translation files (.pot, .po, .mo)
├── releases/          # Release packages (version 0.1.0+)
├── src/
│   ├── Admin/         # AdminController - license management UI
│   ├── Api/           # RestApiController - license validation endpoints
│   ├── Checkout/      # CheckoutController - domain field at checkout
│   ├── Frontend/      # AccountController - customer licenses page
│   ├── License/       # License model and LicenseManager
│   └── Product/       # LicensedProduct type and LicensedProductType
├── templates/
│   ├── admin/         # Twig templates for admin views
│   └── frontend/      # Twig templates for customer views
└── vendor/            # Composer dependencies (Twig)
```

### Database Tables

Created on plugin activation via `Installer::createTables()`:

- `{prefix}_wc_licensed_product_licenses` - License keys with domain binding
- `{prefix}_wc_licensed_product_versions` - Product version tracking

### REST API Endpoints

Base: `/wp-json/wc-licensed-product/v1/`

| Endpoint    | Method | Description                     |
| ----------- | ------ | ------------------------------- |
| `/validate` | POST   | Validate license key for domain |
| `/status`   | POST   | Get license status              |
| `/activate` | POST   | Activate license on domain      |

Full API documentation available in `openapi.json` (OpenAPI 3.1 specification).

### Key Classes

- `Plugin` (singleton) - Main controller, initializes all components
- `Installer` - Database setup, activation/deactivation hooks
- `LicenseManager` - License CRUD, validation, key generation
- `License` - Entity model with status constants
- `LicensedProduct` - Extends WC_Product for licensed products
- `LicensedProductType` - Registers product type with WooCommerce

---

## Session History

### 2026-01-21 - Initial Implementation (v0.0.1)

**Implemented:**

- Created basic WordPress/WooCommerce plugin structure
- Implemented domain-bound license management via REST API
- Added "Licensed Product" WooCommerce product type
- License generation on order completion (XXXX-XXXX-XXXX-XXXX format)
- Customer account page for viewing licenses
- Admin CRUD interface for license management
- Checkout domain field for licensed products
- German (de_CH) translation

**Architecture decisions:**

- Used Twig 3.0 for templating with fallback PHP templates
- License keys use format XXXX-XXXX-XXXX-XXXX (alphanumeric)
- Licenses bound to normalized domains (no protocol, no www, lowercase)
- REST API at `/wp-json/wc-licensed-product/v1/`
- Custom database tables for licenses and product versions
- WooCommerce HPOS compatibility included

### 2026-01-21 - Version 0.0.2 Features

**Implemented:**

- Product version management UI (meta box on product edit page)
- AJAX-based version CRUD operations
- Email notifications with license keys on order completion
- REST API rate limiting (30 requests/minute per IP)

**New classes:**

- `ProductVersion` - Version entity model
- `VersionManager` - Version CRUD operations
- `VersionAdminController` - Admin UI for versions
- `LicenseEmailController` - Email integration

**Technical notes:**

- Rate limiting uses WordPress transients
- IP detection supports Cloudflare and proxies
- Version management uses AJAX for smooth UX

### 2026-01-21 - Version 0.0.3 Features

**Implemented:**

- File attachment support for product versions (WordPress Media Library integration)
- Version auto-detection from uploaded filenames (e.g., `plugin-v1.2.3.zip`)
- Customer download page for purchased licenses with secure authenticated downloads
- License key copy-to-clipboard functionality on account page
- New card-based UI for customer licenses page with download section
- Product versions meta box visibility fix (now hidden for non-licensed product types)

**New classes:**

- `DownloadController` - Secure file delivery with hash-based URL verification

**Technical notes:**

- Secure download URLs use hash verification (license_id-version_id-hash format)
- Database schema updated: `attachment_id` column added to versions table
- ProductVersion model extended with `getEffectiveDownloadUrl()` and `getDownloadFilename()`
- Media uploader filters for zip files only
- Clipboard API with fallback for older browsers
- Card-based responsive UI design for licenses page

**Bug fixes:**

- Fixed product versions meta box visibility for non-licensed product types (targets `#wc_licensed_product_versions` container)

### 2026-01-21 - Version 0.0.4 Features

**Implemented:**

- WooCommerce settings tab "Licensed Products" for default license settings
- Default settings for Max Activations, License Validity, and Bind to Major Version
- Per-product settings override global defaults (empty = use default)
- Settings link in product edit page pointing to WooCommerce settings

**New classes:**

- `SettingsController` - WooCommerce settings tab integration

**Technical notes:**

- Settings stored using WooCommerce options API
- LicensedProduct model falls back to global defaults when product settings are empty
- Added `has_custom_*` methods to check if product has overridden defaults
- Product edit panel shows placeholders with default values

### 2026-01-21 - Version 0.0.5 Features

**Implemented:**

- Bulk license operations in admin (activate, deactivate, revoke, extend, delete)
- License renewal/extension functionality (extend by 30/90/365 days)
- Set license to lifetime (remove expiration)
- Quick action buttons per license row (+30d, ∞, Revoke, Delete)
- Checkbox selection with select-all for bulk operations
- Improved admin notices for bulk operation results

**New methods in LicenseManager:**

- `extendLicense()` - Extend license by specified days
- `setLicenseLifetime()` - Remove expiration (set to lifetime)
- `bulkUpdateStatus()` - Bulk update license status
- `bulkDelete()` - Bulk delete licenses
- `bulkExtend()` - Bulk extend licenses

**Technical notes:**

- Admin page redesigned with WordPress list table styling
- Twig template functions for generating action URLs with nonces
- JavaScript for checkbox synchronization and bulk action handling
- Row-actions pattern for cleaner per-license action UI

### 2026-01-21 - Version 0.0.6 Features

**Implemented:**

- License usage statistics/analytics dashboard (WooCommerce > License Dashboard)
- License transfer functionality (change domain from admin)
- Export licenses to CSV with all related data
- OpenAPI 3.1 specification for REST API (`openapi.json`)
- Removed `/deactivate` API endpoint (admin-only operation now)

**New methods in LicenseManager:**

- `transferLicense()` - Transfer license to new domain
- `getStatistics()` - Get comprehensive license statistics
- `exportLicensesForCsv()` - Export all licenses for CSV download

**New files:**

- `templates/admin/dashboard.html.twig` - Dashboard template
- `openapi.json` - OpenAPI 3.1 specification

**Technical notes:**

- Dashboard shows status cards, monthly chart, top products/domains
- Transfer uses modal dialog with form submission
- CSV export includes BOM for UTF-8 Excel compatibility
- OpenAPI spec documents all endpoints with examples and error responses
- Statistics query uses SQL aggregation for performance

### 2026-01-21 - Version 0.0.7 Features

**Implemented:**

- License Dashboard moved to WooCommerce Reports section (Reports > Licenses tab)
- License search and filtering in admin (by key, domain, status, product)
- Customer-facing license transfer request with AJAX modal
- Email notifications for license expiration warnings (7 days and 1 day before)
- Bulk import licenses from CSV with validation and options

**New methods in LicenseManager:**

- `getLicensesExpiringSoon()` - Get licenses expiring within specified days
- `markExpirationNotified()` - Track expiration notification state
- `wasExpirationNotified()` - Check if notification already sent
- `importLicense()` - Create license from imported data

**Updated controllers:**

- `AdminController` - Added Reports integration, search/filter handling, CSV import
- `AccountController` - Added customer transfer AJAX handler with domain validation
- `LicenseEmailController` - Added cron scheduling and expiration warning emails
- `Installer` - Clears cron events on deactivation

**New UI features:**

- Search box and filter dropdowns on licenses page
- Transfer button and modal on customer licenses page
- Import CSV page with format documentation
- Pagination preserves filter state

**Technical notes:**

- WooCommerce Reports integration uses `woocommerce_admin_reports` filter
- Customer transfer uses AJAX with nonce verification
- Expiration warnings use WordPress cron with daily schedule
- CSV import supports both exported format and simplified format
- User meta tracks expiration notifications to prevent duplicates

### 2026-01-21 - Version 0.0.8 Features

**Implemented:**

- Removed "Current Version" field from product license settings
- Current version now automatically derived from latest product version in database
- Refactored email system to use WooCommerce transactional email system
- License Expiration Warning email configurable via WooCommerce > Settings > Emails
- Uses WooCommerce's email header/footer templates for consistent styling
- Configurable warning days for expiration notifications (first and second warning)

**New classes:**

- `LicenseExpirationEmail` - WooCommerce WC_Email subclass for license expiration warnings

**Modified classes:**

- `LicensedProduct` - `get_current_version()` and `get_major_version()` now query VersionManager
- `LicensedProductType` - Removed Current Version field from product data panel
- `VersionAdminController` - Removed automatic update of `_licensed_current_version` meta
- `LicenseEmailController` - Registers WooCommerce email class, uses WC email system for sending
- `SettingsController` - Updated email section to link to WooCommerce email settings

**Technical notes:**

- Email uses WooCommerce's `emails/email-header.php` and `emails/email-footer.php` templates
- Email content is rendered inline, inheriting WooCommerce's styling and customizations
- Admins can customize subject, heading, additional content, and enable/disable via WC settings
- Expiration warning schedule (days before) remains in plugin settings
- Email enable/disable is controlled through WooCommerce email settings

### 2026-01-21 - Version 0.0.9 Features

**Implemented:**

- Created API client examples for multiple programming languages
- Documentation for REST API usage with code examples

**New files:**

- `docs/client-examples/README.md` - API documentation and overview
- `docs/client-examples/curl.sh` - cURL command examples
- `docs/client-examples/php-client.php` - PHP client class with examples
- `docs/client-examples/python-client.py` - Python client class with examples
- `docs/client-examples/javascript-client.js` - JavaScript/Node.js client class
- `docs/client-examples/csharp-client.cs` - C# client class with examples

**Technical notes:**

- All client examples include error handling for rate limiting (HTTP 429)
- Examples demonstrate all three API endpoints: validate, status, activate
- JavaScript client works in both browser and Node.js environments
- Python client uses dataclasses for type-safe responses
- C# client uses async/await patterns and System.Text.Json

### 2026-01-21 - Bug Fixes (pre-v0.0.10)

**Fixed bugs:**

- Fixed: No licenses generated when order is marked as done
- Fixed: No domain field in WooCommerce Checkout Blocks

**New files:**

- `src/Checkout/CheckoutBlocksIntegration.php` - WooCommerce Blocks checkout integration
- `src/Checkout/StoreApiExtension.php` - Store API extension for domain field handling
- `assets/js/checkout-blocks.js` - Frontend JavaScript for checkout block domain field

**Modified files:**

- `src/Plugin.php` - Added checkout blocks registration and multiple order status hooks
- `src/License/LicenseManager.php` - Fixed product type check in `generateLicense()`

**Technical notes:**

- Added support for WooCommerce Checkout Blocks (default since WC 8.3+)
- `CheckoutBlocksIntegration` implements `IntegrationInterface` for block checkout
- `StoreApiExtension` handles server-side domain data via Store API
- License generation now triggers on `completed`, `processing`, and `payment_complete` hooks
- Fixed `LicenseManager::generateLicense()` to properly check product type with `is_type()`
- Classic checkout (`woocommerce_after_order_notes`) still works for stores using classic checkout

**Additional bug fix:**

- Fixed: Version uploads not appearing in list after creation

**Modified files:**

- `src/Product/VersionManager.php` - Fixed null `attachment_id` handling in `createVersion()`
- `src/Admin/VersionAdminController.php` - Added product validation and error logging

**Technical notes:**

- `$wpdb->insert()` now only includes `attachment_id` field when it has a valid value
- Added error logging for version creation failures to aid debugging
- Improved meta box visibility logic for new products

### 2026-01-21 - Version 0.0.10 Features

**Implemented:**

- License meta box on WooCommerce order edit pages
- Editable order domain field with AJAX-based inline editing
- Editable license domains directly from the order page
- Licenses table showing all licenses associated with an order
- Support for both classic orders and HPOS (High-Performance Order Storage)

**New files:**

- `src/Admin/OrderLicenseController.php` - Order page license integration
- `assets/js/order-licenses.js` - JavaScript for inline domain editing

**New methods in LicenseManager:**

- `getLicensesByOrder()` - Get all licenses for a specific order

**Technical notes:**

- Meta box automatically detects HPOS vs classic order storage
- AJAX handlers for updating both order domain and individual license domains
- Domain validation with normalization (strips protocol, www prefix)
- Inline edit UI with save/cancel for license domains
- Links to full licenses management page for advanced actions

**Additional features added in this session:**

- Inline editing for license fields (status, expiry date, domain) in admin licenses overview
- Copy license key button with clipboard API and fallback for older browsers
- Live search for licenses in admin overview with AJAX-powered results dropdown
- Settings link added to plugin action links in Plugins list
- Fixed 404 error on licenses menu item in customer account
- Fixed Twig template cache issues with `auto_reload` option

**New files:**

- `assets/js/admin-licenses.js` - JavaScript for live search, inline editing, and copy functionality

**New methods in LicenseManager:**

- `updateLicenseExpiry()` - Update license expiry date with auto-reactivation for expired licenses

**AJAX handlers added to AdminController:**

- `handleAjaxStatusUpdate()` - Update license status via AJAX
- `handleAjaxExpiryUpdate()` - Update license expiry date via AJAX
- `handleAjaxDomainUpdate()` - Update license domain via AJAX
- `handleAjaxRevoke()` - Revoke license via AJAX

**Technical notes:**

- Live search uses 300ms debounce and keyboard navigation (arrows, enter, escape)
- Inline editing shows edit icons on hover, supports enter to save and escape to cancel
- Copy button uses Clipboard API with textarea fallback for older browsers
- All AJAX handlers use nonce verification (`wclp_inline_edit` nonce)
- Twig configured with `auto_reload => true` for development to always check template changes

**Bug fix:**

- Fixed: Licenses menu item in customer account page resulted in 404 error
- Root cause: WooCommerce My Account endpoints require both `add_rewrite_endpoint()` AND registration with `woocommerce_get_query_vars` filter
- Fix: Added `addLicensesQueryVar()` method to register the endpoint query var with WooCommerce

**Release v0.0.10:**

- Created release package: `releases/wc-licensed-product-0.0.10.zip` (472 KB)
- SHA256: `3f4a093f6d4d02389082c3a88c00542f477ab3ad4d4a0c65079e524ef0739620`
- Tagged as `v0.0.10` and pushed to `main` branch

### 2026-01-22 - Version 0.0.11 Features

**Implemented:**

- Created date column added to admin license overview showing when each license was generated

**Modified files:**

- `templates/admin/licenses.html.twig` - Added "Created" column to table header and data cells
- `src/Admin/AdminController.php` - Added "Created" column to PHP fallback rendering
- `src/Plugin.php` - Added `getInstance()` alias for singleton access

**Technical notes:**

- New column displays license creation date in Y-m-d format
- Both Twig template and PHP fallback updated for consistency
- WooCommerce Analytics integration was attempted but removed due to WordPress permission issues with submenu pages

**Release v0.0.11:**

- Created release package: `releases/wc-licensed-product-0.0.11.zip` (473 KB)
- SHA256: `c3f66c4ac54741053f87ce1a63b4ddb49ad9707d5c194a271311bb95518ab13c`
- Tagged as `v0.0.11` and pushed to `main` branch

### 2026-01-22 - Version 0.1.0 - First Stable Minor Release

**Overview:**

First stable minor release after comprehensive code review for WordPress/WooCommerce best practices and security.

**Code Review Findings:**

Security practices verified:

- Input sanitization with `sanitize_text_field()`, `absint()`, `esc_attr()`, `esc_html()`, `esc_url()`
- Nonce verification on all forms and AJAX handlers
- Capability checks with `current_user_can('manage_woocommerce')`
- SQL injection prevention using `$wpdb->prepare()` throughout
- Secure download URLs with hash verification using `hash_equals()`
- Rate limiting on REST API (30 requests/minute)
- Cryptographically secure license key generation with `random_int()`

**Bug Fixes:**

- Fixed `VersionManager::updateVersion()` null format handling for attachment ID updates
- Improved input sanitization in `AdminController::enqueueAdminAssets()` for page context checks

**Documentation Updates:**

- Updated README.md with complete feature documentation
- Added new features: Live Search, Inline Editing, Order Integration, WooCommerce HPOS compatibility, Checkout Blocks support
- Removed outdated "Current Version" field from usage instructions

**Translation Updates:**

- Regenerated .pot template with all current strings
- Updated German (de_CH) translation with new strings
- Compiled .mo file for production use

**Modified files:**

- `src/Product/VersionManager.php` - Fixed null format handling in attachment update
- `src/Admin/AdminController.php` - Improved $_GET sanitization for page context
- `README.md` - Updated feature documentation
- `CHANGELOG.md` - Added 0.1.0 release notes
- `wc-licensed-product.php` - Version bump to 0.1.0
- `languages/*` - Updated all translation files

**Release v0.1.0:**

- Created release package: `releases/wc-licensed-product-0.1.0.zip` (478 KB)
- SHA256: `62638e240315107098be4cb40faff8395e9e1b719d79b73d80e69d680b305e87`
- Tagged as `v0.1.0` and pushed to `main` branch

### 2026-01-22 - Version 0.2.0 - Security & Integrity Features

**Overview:**

Added response signing for REST API security and SHA256 checksum validation for uploaded version files.

**Implemented:**

- REST API response signing using HMAC-SHA256 for tamper-proof responses
- SHA256 hash field for product version uploads with server-side validation
- Per-license key derivation using HKDF-like approach
- Automatic signature headers on license API endpoints

**Removed:**

- External download URL field from product version form
- Direct URL support in version uploads (Media Library only now)

**New files:**

- `src/Api/ResponseSigner.php` - HMAC-SHA256 response signing class

**Modified files:**

- `src/Installer.php` - Added `file_hash` column to versions table schema
- `src/Product/ProductVersion.php` - Added `fileHash` property and getter
- `src/Product/VersionManager.php` - Removed `$downloadUrl` parameter, added `$fileHash` with validation
- `src/Admin/VersionAdminController.php` - Removed URL field, added SHA256 hash field
- `assets/js/versions.js` - Updated form handling for hash field
- `src/Plugin.php` - Initialize ResponseSigner when server secret is configured

**Technical notes:**

- Response signing only activates when `WC_LICENSE_SERVER_SECRET` constant is defined
- Signature algorithm: `HMAC-SHA256(derived_key, timestamp + ':' + canonical_json)`
- Key derivation: `HMAC-SHA256(HMAC-SHA256(license_key, server_secret) + "\x01", server_secret)`
- Hash validation throws `InvalidArgumentException` on mismatch
- Compatible with `magdev/wc-licensed-product-client` SecureLicenseClient
- Database migration handled by WordPress `dbDelta()` function

**Configuration:**

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()`

### 2026-01-23 - Version 0.3.5 - Download List UI Improvement

**Overview:**

Improved the download list layout in customer account licenses page with a two-row format.

**Implemented:**

- Downloads now displayed in two rows per entry
- First row: File download link
- Second row: Metadata (version, date, checksum)
- Better visual separation and readability

**Modified files:**

- `templates/frontend/licenses.html.twig` - Restructured download list with two-row layout
- `assets/css/frontend.css` - Added `.download-item`, `.download-row-file`, `.download-row-meta` styles

**Technical notes:**

- Changed `<li>` from single-row flex to column flex layout
- Metadata row indented with left padding for visual hierarchy
- Updated responsive CSS for mobile devices