wc-tier-and-package-prices/CHANGELOG.md

# Changelog

All notable changes to WooCommerce Tier and Package Prices will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [1.1.19] - 2025-12-22

### Fixed

- Settings page still appearing twice despite instance caching
- Duplicate detection using strict instance comparison failing for different object instances

### Changed

- Enhanced duplicate detection to check by class type and ID instead of instance
- Added `instanceof WC_TPP_Settings` check
- Added ID-based duplicate detection via `get_id()` method and direct property access
- Multiple fallback checks to catch duplicates regardless of instance identity

### Technical Details

- Previous strict comparison (`===`) failed when different instances of same class existed
- New approach checks: instanceof, get_id() method, and id property
- Returns early if any settings page with ID 'tier_package_prices' found
- Prevents duplicates even if settings instance recreated or serialized

## [1.1.18] - 2025-12-22

### Fixed

- **ROOT CAUSE IDENTIFIED**: Settings page rendering twice due to automatic instantiation in settings file
- Settings file being included multiple times via Composer autoloader creating duplicate instances

### Changed

- Removed `return new WC_TPP_Settings();` from bottom of settings file
- Changed admin class to explicitly instantiate settings with `new WC_TPP_Settings()`
- Changed from `include` to `require_once` for settings file to prevent multiple loads

### Technical Details

- Settings file (class-wc-tpp-settings.php) was creating instance automatically on include
- File is in Composer's classmap, so when autoloaded it executed instantiation again
- Each include/autoload created new instance even with singleton pattern in admin class
- Solution: Remove automatic instantiation, use `require_once` + explicit `new` in admin class
- Now settings instance only created once, explicitly, when needed by filter
- Composer autoload can load class definition without side effects

## [1.1.17] - 2025-12-22

### Fixed

- Settings page still rendering twice despite singleton pattern in v1.1.16
- Filter adding settings instance to array multiple times when called repeatedly

### Changed

- Added duplicate detection in `add_settings_page()` filter method
- Filter now checks if settings instance already exists in array before adding

### Technical Details

- Added foreach loop to check existing settings pages in array
- Uses strict comparison (`===`) to detect if exact instance already present
- Returns early if settings instance found, preventing duplicate array entries
- Complements singleton pattern from v1.1.16 with array-level duplicate prevention
- Handles edge case where WooCommerce calls filter multiple times

## [1.1.16] - 2025-12-22

### Fixed

- Settings page still rendering twice in WooCommerce backend despite v1.1.15 fix
- Multiple instantiation of WC_TPP_Admin and WC_TPP_Settings classes

### Changed

- Implemented singleton pattern for WC_TPP_Admin class with `get_instance()` method
- Made WC_TPP_Admin constructor private to prevent direct instantiation
- Added static caching of WC_TPP_Settings instance to prevent duplicate creation
- Changed class instantiation from `new WC_TPP_Admin()` to `WC_TPP_Admin::get_instance()`

### Technical Details

- Added `private static $instance` property to WC_TPP_Admin class
- Added `private static $settings_instance` property to cache settings page instance
- Modified `add_settings_page()` to check and reuse cached settings instance
- Ensures only one instance of each class exists throughout plugin lifecycle
- Prevents duplicate filter registrations even if called multiple times

## [1.1.15] - 2025-12-22

### Fixed

- Settings page rendering twice in WooCommerce settings
- Duplicate instantiation of WC_TPP_Settings class causing double rendering

### Technical Details

- Removed conditional `if (class_exists('WC_TPP_Settings'))` wrapper from settings return statement
- Settings class now only instantiated via `return new WC_TPP_Settings();` when included by admin class
- Matches v1.1.2 pattern where settings file returns instance without automatic instantiation
- Prevents double registration in WooCommerce settings pages array

## [1.1.14] - 2025-12-22

### Fixed

- **CRITICAL:** Plugin completely non-functional in v1.1.8-1.1.13 - no settings, no frontend, no backend
- Classes never instantiated due to incorrect initialization pattern introduced in v1.1.8
- Restored v1.1.2 pattern: classes auto-instantiate when files are included
- All plugin functionality now working: settings page, product meta boxes, frontend display, cart integration

### Changed

- Reverted to direct class instantiation pattern from v1.1.2 (last known working version)
- Removed `init_classes()` method and `woocommerce_loaded` hook approach from v1.1.8
- Each class file now instantiates itself with `new ClassName()` at end of file
- Simplified plugin initialization for better reliability

### Technical Details

- Restored class instantiation in all 5 component files:
  - `class-wc-tpp-admin.php`: Added `new WC_TPP_Admin();` after class declaration
  - `class-wc-tpp-product-meta.php`: Added `new WC_TPP_Product_Meta();` after class declaration
  - `class-wc-tpp-frontend.php`: Added `new WC_TPP_Frontend();` after class declaration
  - `class-wc-tpp-cart.php`: Added `new WC_TPP_Cart();` after class declaration
  - `class-wc-tpp-settings.php`: Already has instantiation via return statement
- Removed `init_classes()` method from main plugin class
- Removed `woocommerce_loaded` hook that delayed class instantiation
- Classes now instantiate immediately when `require_once` loads them
- All `class_exists()` guards remain in place for redeclaration protection

## [1.1.13] - 2025-12-22

### Fixed

- **CRITICAL:** Class redeclaration errors for all plugin component classes affecting version 1.1.12
- Fatal errors "Cannot redeclare class WC_TPP_Admin", "Cannot redeclare class WC_TPP_Product_Meta", "Cannot redeclare class WC_TPP_Frontend", "Cannot redeclare class WC_TPP_Cart", "Cannot redeclare class WC_TPP_Settings"
- Plugin functionality completely broken in v1.1.12 - no settings page, no frontend display, no backend controls
- All plugin features now working correctly after adding class guards

### Technical Details

- Wrapped all 5 plugin component class declarations in `class_exists()` checks:
  - `WC_TPP_Admin` (includes/class-wc-tpp-admin.php)
  - `WC_TPP_Product_Meta` (includes/class-wc-tpp-product-meta.php)
  - `WC_TPP_Frontend` (includes/class-wc-tpp-frontend.php)
  - `WC_TPP_Cart` (includes/class-wc-tpp-cart.php)
  - `WC_TPP_Settings` (includes/class-wc-tpp-settings.php)
- Completes comprehensive redeclaration protection started in v1.1.9-1.1.12
- All functions, constants, and classes now fully protected against redeclaration
- Plugin now activates and functions correctly without fatal errors

## [1.1.12] - 2025-12-22

### Fixed

- **CRITICAL:** Class redeclaration error for `WC_Tier_Package_Prices` affecting version 1.1.11
- Fatal error "Cannot redeclare class WC_Tier_Package_Prices" when plugin file loaded multiple times
- Plugin activation failures caused by class redeclaration

### Technical Details

- Wrapped `WC_Tier_Package_Prices` class declaration in `class_exists()` check
- Completes comprehensive redeclaration protection for all plugin components
- Prevents fatal errors during WordPress plugin activation/deactivation cycles
- All functions, constants, and classes now safely guarded against redeclaration

## [1.1.11] - 2025-12-22

### Fixed

- **CRITICAL:** Constant redeclaration warnings/errors for plugin constants affecting versions 1.1.3-1.1.10
- Potential errors when plugin constants (WC_TPP_VERSION, WC_TPP_PLUGIN_DIR, etc.) already defined
- Plugin initialization failures caused by constant redeclaration

### Technical Details

- Wrapped all `define()` calls in `defined()` checks for WC_TPP_VERSION, WC_TPP_PLUGIN_DIR, WC_TPP_PLUGIN_URL, WC_TPP_PLUGIN_BASENAME
- Prevents warnings/errors during WordPress plugin activation/deactivation cycles
- Completes comprehensive protection against all redeclaration issues
- All global functions and constants now safely guarded

## [1.1.10] - 2025-12-22

### Fixed

- **CRITICAL:** Function redeclaration error for `wc_tpp_init()` affecting version 1.1.9
- Fatal error "Cannot redeclare function wc_tpp_init()" when plugin file loaded multiple times
- Plugin activation failures caused by function redeclaration

### Technical Details

- Wrapped `wc_tpp_init()` function in `function_exists()` check
- Completes the fix started in v1.1.9 by protecting all global functions
- Prevents fatal errors during WordPress plugin activation cycles
- Both `wc_tpp_woocommerce_missing_notice()` and `wc_tpp_init()` now safely guarded

## [1.1.9] - 2025-12-22

### Fixed

- **CRITICAL:** Function redeclaration error for `wc_tpp_woocommerce_missing_notice()` affecting versions 1.1.3-1.1.8
- Fatal error "Cannot redeclare function wc_tpp_woocommerce_missing_notice()" when plugin file loaded multiple times
- Plugin activation and deactivation failures caused by function redeclaration

### Technical Details

- Wrapped `wc_tpp_woocommerce_missing_notice()` function in `function_exists()` check
- Prevents fatal error during WordPress plugin activation/deactivation cycles
- Ensures function can safely be declared even if file is included multiple times
- Moved function declaration before WooCommerce check for better code organization

## [1.1.8] - 2025-12-22

### Fixed

- **CRITICAL:** Plugin activation fatal error introduced in v1.1.3-v1.1.7
- Fixed premature class instantiation of `WC_TPP_Admin` and `WC_TPP_Product_Meta`
- Both classes now instantiated via `woocommerce_loaded` hook after WooCommerce is available
- Resolves WordPress 6.9.x and WooCommerce 10.x compatibility issues

### Technical Details

- Removed `new WC_TPP_Admin();` from bottom of class-wc-tpp-admin.php
- Removed `new WC_TPP_Product_Meta();` from bottom of class-wc-tpp-product-meta.php
- Added both classes to `init_classes()` method in main plugin file
- All four main classes (Admin, Product Meta, Frontend, Cart) now follow same initialization pattern
- Ensures WooCommerce hooks are available before registration

## [1.1.7] - 2025-12-22

### Added

- Optional text labels for tier pricing (similar to package labels)
- Clickable tier pricing rows that auto-populate quantity field
- Add to Cart button auto-disable when quantity is 0 or less

### Enhanced

- Tier pricing table rows now clickable with visual hover feedback
- Clicking a tier row sets quantity to that tier's minimum quantity
- Smooth scroll animation to quantity field when tier is clicked
- Add to Cart button disabled state with visual feedback (opacity, cursor)
- Tier labels display below quantity in frontend table (italic, gray text)

### Technical Details

- Added optional `label` field to tier pricing meta box (admin/tier-row.twig)
- Updated tier save logic to store label field (class-wc-tpp-product-meta.php)
- Enhanced tier pricing template to display labels (frontend/tier-pricing-table.twig)
- Added click handler for tier rows (assets/js/frontend.js)
- Added `updateAddToCartButton()` function to manage button state
- CSS: `.wc-tpp-tier-label` styling for tier labels
- CSS: Clickable cursor and hover animation for tier rows
- CSS: Disabled button styling (`.single_add_to_cart_button:disabled`)

## [1.1.6] - 2025-12-21

### Fixed
- **CRITICAL:** Plugin activation fatal error in v1.1.3, v1.1.4, and v1.1.5
- Fatal error caused by premature class instantiation before WooCommerce is loaded
- Removed immediate class instantiation from `class-wc-tpp-cart.php` and `class-wc-tpp-frontend.php`

### Technical
- Moved `WC_TPP_Cart` and `WC_TPP_Frontend` instantiation to `woocommerce_loaded` hook
- Added `init_classes()` method to main plugin class for controlled class initialization
- Ensures WooCommerce is fully loaded before registering hooks that depend on WC functions
- Fixed hook registration timing to prevent accessing WooCommerce before it's available

## [1.1.5] - 2025-12-21

### Fixed
- **CRITICAL:** Plugin activation error in v1.1.3 and v1.1.4 caused by `add_cart_quantity_css()` method
- Fatal error when WooCommerce cart object not available during plugin initialization
- Frontend errors on admin pages and during activation

### Technical
- Added `function_exists('WC')` check before accessing WooCommerce functions
- Added `is_admin()` check to prevent CSS injection on admin pages
- Enhanced error prevention in `add_cart_quantity_css()` method

## [1.1.4] - 2025-12-21

### Added
- WooCommerce Blocks support for quantity restrictions
- `woocommerce_store_api_product_quantity_editable` filter for block-based carts
- `block_quantity_editable()` method in WC_TPP_Cart class
- CSS targeting for `.wc-block-components-quantity-selector` elements

### Enhanced
- "View Options" button styling to match standard WooCommerce "Add to Cart" buttons
- Button padding, font weight, and border radius for better visual consistency
- Hover effects with smooth transitions

### Fixed
- WooCommerce blocks cart quantity selector visibility for restricted products
- WooCommerce blocks mini-cart quantity selector visibility

### Technical
- Added Store API integration for block-based cart/mini-cart
- Enhanced CSS for block cart items with product-specific selectors
- Improved button styling with WooCommerce standard values (0.618em × 1em padding)
- Added transition effects for better UX

## [1.1.3] - 2025-12-21

### Fixed
- Cart quantity input visibility issue in cart and cart sidebar for restricted products
- Enhanced filter priority (999) to ensure quantity hiding runs after other plugins
- Mini-cart quantity input now properly hidden for restricted products

### Added
- `woocommerce_widget_cart_item_quantity` filter support for mini-cart
- `add_cart_quantity_css()` method for dynamic CSS injection
- `data-product-id` attribute to quantity spans for targeted CSS selectors
- CSS class `wc-tpp-restricted-qty` for improved targeting

### Technical
- Increased filter priority from 10 to 999 for `woocommerce_cart_item_quantity`
- Added `maybe_hide_mini_cart_quantity_input()` method in WC_TPP_Cart class
- Dynamic CSS injection via `wp_head` action as fallback
- Used both sibling (+) and general sibling (~) CSS selectors for DOM variations

## [1.1.2] - 2025-12-21

### Added
- Catalog "View Options" button for products with quantity restrictions
- Automatic button replacement in shop/category/archive pages
- Eye icon (Dashicons) for "View Options" button styling

### Changed
- "Add to Cart" button replaced with "View Options" link on catalog pages for restricted products
- CSS now loads on all WooCommerce pages (shop, cart, checkout, product)
- Catalog buttons now direct to product page instead of adding to cart

### Technical
- Added `has_quantity_restriction()` static method in WC_TPP_Frontend class
- Added `modify_catalog_add_to_cart_button()` method in WC_TPP_Frontend class
- Extended `woocommerce_loop_add_to_cart_link` filter hook
- CSS classes: `wc-tpp-view-options`, `wc-tpp-cart-quantity`, `wc-tpp-restriction-notice`
- Updated `enqueue_scripts()` to load CSS on all WooCommerce pages

### Translations
- Added 2 new translatable strings
- Updated all translations (en_US, de_DE, de_CH_informal)
- Compiled all .mo files with new strings

## [1.1.1] - 2025-12-21

### Added
- Cart quantity field hiding when package restriction is enabled
- Automatic read-only quantity display in cart for restricted products

### Changed
- Cart quantity input replaced with plain text when restrictions apply
- Enhanced cart display to prevent quantity modification for restricted products

### Fixed
- Cart quantity bypass vulnerability for package-restricted products

### Technical
- Added `maybe_hide_cart_quantity_input()` method in WC_TPP_Cart class
- Extended `woocommerce_cart_item_quantity` filter hook
- CSS class `wc-tpp-cart-quantity` for styled quantity display

## [1.1.0] - 2025-12-21

### Added
- Package quantity restriction feature
- Global setting to restrict quantities to defined package sizes
- Per-product setting to restrict quantities to defined package sizes
- Frontend validation preventing non-package quantities
- Server-side cart validation for package quantities
- User-friendly error messages showing available package sizes
- Automatic quantity field hiding when restriction is enabled
- Package selection UI with highlighted states

### Changed
- Enhanced package pricing display template with restriction mode support
- Improved JavaScript to handle restricted mode package selection
- Updated frontend to show "Choose a package size below" notice in restricted mode

### Technical
- Added `validate_package_quantity()` method in WC_TPP_Cart class
- Added `maybe_hide_quantity_input()` method in WC_TPP_Frontend class
- Extended `woocommerce_add_to_cart_validation` filter hook
- Added `wc-tpp-restricted-mode` CSS class for styling
- New product meta: `_wc_tpp_restrict_to_packages`
- New global option: `wc_tpp_restrict_package_quantities`

### Translations
- Added 7 new translatable strings
- Updated all translations (en_US, de_DE, de_CH_informal)
- Compiled all .mo files with new strings

## [1.0.2] - 2025-12-21

### Changed
- Migrated settings to WooCommerce Settings page as dedicated tab
- Settings now appear under WooCommerce > Settings > Tier & Package Prices
- Improved integration with WooCommerce native settings API

### Added
- WC_TPP_Settings class extending WC_Settings_Page
- Better integration with WooCommerce settings system
- Consistent UI with other WooCommerce settings tabs

### Removed
- Standalone settings submenu (WooCommerce > Tier & Package Prices)
- Custom settings template (templates/admin/settings-page.twig)

### Technical
- Implemented WooCommerce settings filter hook (woocommerce_get_settings_pages)
- Uses WC_Admin_Settings for rendering and saving
- Automatic settings persistence via WooCommerce API

## [1.0.1] - 2025-12-21

### Added
- Twig template engine integration for all templates
- Template loader class with WordPress integration
- German (Switzerland, Informal) translation (de_CH_informal)
- Composer dependency management
- Comprehensive translation support in Twig templates
- Template caching support (disabled in debug mode)

### Changed
- Migrated all PHP templates to Twig format (.twig)
- Improved template organization and separation of concerns
- Enhanced security with automatic HTML escaping in templates
- Updated composer.json with complete package metadata

### Removed
- Old PHP template files (replaced with Twig)

### Technical
- Added Twig v3.22.2 dependency
- Created WC_TPP_Template_Loader class for centralized template rendering
- Integrated WordPress functions (__(), _e(), esc_*, wc_price()) into Twig
- Added Swiss German localization with informal address form
- Organized templates into admin/ and frontend/ directories

## [1.0.0] - 2025-12-21

### Added
- Initial release
- Tier pricing functionality (quantity-based discounts)
- Package pricing functionality (fixed-price bundles)
- Admin settings page for plugin configuration
- Product meta boxes for configuring tier and package prices
- Frontend pricing tables display
- Cart integration for automatic price calculation
- WooCommerce HPOS compatibility
- Multilingual support with text domain
- German (Germany) translation (de_DE)
- English (US) translation (en_US)

### Features
- Volume discounts based on quantity thresholds
- Fixed-price packages with custom labels
- Configurable display positions (before/after cart button, after price)
- Real-time price updates in cart
- Responsive pricing tables
- Admin-friendly interface for price management