wc-tier-and-package-prices/includes/class-wc-tpp-product-meta.php

<?php
/**
 * Product meta boxes for tier and package pricing
 */

if (!defined('ABSPATH')) {
    exit;
}

class WC_TPP_Product_Meta {

    public function __construct() {
        add_action('woocommerce_product_options_pricing', array($this, 'add_tier_pricing_fields'));
        add_action('woocommerce_product_options_pricing', array($this, 'add_package_pricing_fields'));
        add_action('woocommerce_process_product_meta', array($this, 'save_tier_package_fields'));
    }

    public function add_tier_pricing_fields() {
        global $post;
        ?>
        <div class="options_group wc-tpp-tier-pricing">
            <p class="form-field">
                <label><?php _e('Tier Pricing', 'wc-tier-package-prices'); ?></label>
                <span class="description"><?php _e('Set quantity-based pricing tiers. Customers get discounted prices when buying in larger quantities.', 'wc-tier-package-prices'); ?></span>
            </p>

            <div class="wc-tpp-tiers-container">
                <?php
                $tiers = get_post_meta($post->ID, '_wc_tpp_tiers', true);
                if (!is_array($tiers)) {
                    $tiers = array();
                }

                foreach ($tiers as $index => $tier) {
                    $this->render_tier_row($index, $tier);
                }
                ?>
            </div>

            <p class="form-field">
                <button type="button" class="button wc-tpp-add-tier"><?php _e('Add Tier', 'wc-tier-package-prices'); ?></button>
            </p>
        </div>
        <?php
    }

    public function add_package_pricing_fields() {
        global $post;
        ?>
        <div class="options_group wc-tpp-package-pricing">
            <p class="form-field">
                <label><?php _e('Package Pricing', 'wc-tier-package-prices'); ?></label>
                <span class="description"><?php _e('Set fixed-price packages with specific quantities. For example: 10 pieces for $50, 25 pieces for $100.', 'wc-tier-package-prices'); ?></span>
            </p>

            <div class="wc-tpp-packages-container">
                <?php
                $packages = get_post_meta($post->ID, '_wc_tpp_packages', true);
                if (!is_array($packages)) {
                    $packages = array();
                }

                foreach ($packages as $index => $package) {
                    $this->render_package_row($index, $package);
                }
                ?>
            </div>

            <p class="form-field">
                <button type="button" class="button wc-tpp-add-package"><?php _e('Add Package', 'wc-tier-package-prices'); ?></button>
            </p>

            <?php
            woocommerce_wp_checkbox(array(
                'id'          => '_wc_tpp_restrict_to_packages',
                'label'       => __('Restrict to Package Quantities', 'wc-tier-package-prices'),
                'description' => __('Only allow quantities defined in packages above', 'wc-tier-package-prices'),
                'desc_tip'    => true,
            ));
            ?>
        </div>

        <script type="text/html" id="wc-tpp-tier-row-template">
            <?php $this->render_tier_row('{{INDEX}}', array('min_qty' => '', 'price' => '', 'label' => '')); ?>
        </script>

        <script type="text/html" id="wc-tpp-package-row-template">
            <?php $this->render_package_row('{{INDEX}}', array('qty' => '', 'price' => '', 'label' => '')); ?>
        </script>
        <?php
    }

    private function render_tier_row($index, $tier) {
        WC_TPP_Template_Loader::get_instance()->display('admin/tier-row.twig', array(
            'index' => $index,
            'tier' => $tier
        ));
    }

    private function render_package_row($index, $package) {
        WC_TPP_Template_Loader::get_instance()->display('admin/package-row.twig', array(
            'index' => $index,
            'package' => $package
        ));
    }

    public function save_tier_package_fields($post_id) {
        // Verify nonce for security
        if (!isset($_POST['woocommerce_meta_nonce']) || !wp_verify_nonce($_POST['woocommerce_meta_nonce'], 'woocommerce_save_data')) {
            return;
        }

        // Check user permissions
        if (!current_user_can('edit_post', $post_id)) {
            return;
        }

        // Avoid auto-save
        if (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) {
            return;
        }

        // Save tier pricing
        if (isset($_POST['_wc_tpp_tiers'])) {
            $tiers = array();
            foreach ($_POST['_wc_tpp_tiers'] as $tier) {
                if (!empty($tier['min_qty']) && !empty($tier['price'])) {
                    $tiers[] = array(
                        'min_qty' => absint($tier['min_qty']),
                        'price' => wc_format_decimal($tier['price']),
                        'label' => sanitize_text_field($tier['label'] ?? '')
                    );
                }
            }
            // Sort by minimum quantity
            usort($tiers, function($a, $b) {
                return $a['min_qty'] - $b['min_qty'];
            });
            update_post_meta($post_id, '_wc_tpp_tiers', $tiers);
        } else {
            delete_post_meta($post_id, '_wc_tpp_tiers');
        }

        // Save package pricing
        if (isset($_POST['_wc_tpp_packages'])) {
            $packages = array();
            foreach ($_POST['_wc_tpp_packages'] as $package) {
                if (!empty($package['qty']) && !empty($package['price'])) {
                    $packages[] = array(
                        'qty' => absint($package['qty']),
                        'price' => wc_format_decimal($package['price']),
                        'label' => sanitize_text_field($package['label'])
                    );
                }
            }
            // Sort by quantity
            usort($packages, function($a, $b) {
                return $a['qty'] - $b['qty'];
            });
            update_post_meta($post_id, '_wc_tpp_packages', $packages);
        } else {
            delete_post_meta($post_id, '_wc_tpp_packages');
        }

        // Save package quantity restriction setting
        $restrict_to_packages = isset($_POST['_wc_tpp_restrict_to_packages']) ? 'yes' : 'no';
        update_post_meta($post_id, '_wc_tpp_restrict_to_packages', $restrict_to_packages);
    }
}