<?php
namespace ToDownload\Discounts;

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

use ToDownload\Data\Orders;
use ToDownload\Hosted\HostedClient;
use ToDownload\PostTypes\DownloadPostType;
use ToDownload\Sellers\Sellers;

final class Discounts {
	// IMPORTANT: WordPress post type keys are normalized to lowercase.
	public const POST_TYPE = 'todownload_discount';

	public static function register(): void {
		add_action('init', [self::class, 'register_post_type']);
		add_action('add_meta_boxes', [self::class, 'register_metaboxes']);
		add_action('save_post_' . self::POST_TYPE, [self::class, 'save_metabox'], 10, 2);
		add_action('admin_enqueue_scripts', [self::class, 'enqueue_admin_styles']);
		add_action('transition_post_status', [self::class, 'on_transition_post_status'], 10, 3);
		add_action('wp_trash_post', [self::class, 'on_trash_post'], 10, 1);
		add_action('before_delete_post', [self::class, 'on_before_delete_post'], 10, 1);

		add_action('ToDownload_after_order_complete', [self::class, 'on_order_complete'], 10, 1);
	}

	public static function on_transition_post_status(string $new_status, string $old_status, $post): void {
		if (!($post instanceof \WP_Post)) {
			return;
		}
		if ($post->post_type !== self::POST_TYPE) {
			return;
		}
		if ($new_status === $old_status) {
			return;
		}
		if (wp_is_post_revision((int) $post->ID)) {
			return;
		}

		// Keep hosted canonical status in sync with publish state.
		$force = ($new_status === 'publish') ? 'active' : 'inactive';
		self::sync_discount_to_hosted((int) $post->ID, $post, null, $force);
	}

	public static function on_trash_post(int $post_id): void {
		$post_id = (int) $post_id;
		if ($post_id <= 0) {
			return;
		}
		$post = get_post($post_id);
		if (!($post instanceof \WP_Post) || $post->post_type !== self::POST_TYPE) {
			return;
		}
		self::sync_discount_to_hosted((int) $post->ID, $post, null, 'inactive');
	}

	public static function on_before_delete_post(int $post_id): void {
		$post_id = (int) $post_id;
		if ($post_id <= 0) {
			return;
		}
		$post = get_post($post_id);
		if (!($post instanceof \WP_Post) || $post->post_type !== self::POST_TYPE) {
			return;
		}
		self::sync_discount_to_hosted((int) $post->ID, $post, null, 'inactive');
	}

	public static function enqueue_admin_styles(): void {
		$screen = get_current_screen();
		if ($screen && $screen->post_type === self::POST_TYPE) {
			$css_ver = ToDownload_VERSION;
			$css_path = ToDownload_PLUGIN_DIR . 'assets/admin-datepicker.css';
			if (is_readable($css_path)) {
				$mtime = filemtime($css_path);
				if ($mtime) {
					$css_ver = (string) $mtime;
				}
			}

			wp_enqueue_style(
				'todownload-admin-datepicker',
				ToDownload_PLUGIN_URL . 'assets/admin-datepicker.css',
				['wp-jquery-ui-dialog'],
				$css_ver
			);

			$js_ver = ToDownload_VERSION;
			$js_path = ToDownload_PLUGIN_DIR . 'assets/admin-discounts-metabox.js';
			if (is_readable($js_path)) {
				$mtime = filemtime($js_path);
				if ($mtime) {
					$js_ver = (string) $mtime;
				}
			}
			wp_enqueue_script(
				'todownload-admin-discounts-metabox',
				ToDownload_PLUGIN_URL . 'assets/admin-discounts-metabox.js',
				[],
				$js_ver,
				true
			);
		}
	}

	public static function register_post_type(): void {
		register_post_type(self::POST_TYPE, [
			'labels' => [
				'name' => __('Discount Codes', '2download-connector'),
				'singular_name' => __('Discount', '2download-connector'),
				'menu_name' => __('Discount Code', '2download-connector'),
				'add_new' => __('Add Discount', '2download-connector'),
				'add_new_item' => __('Add Discount', '2download-connector'),
				'edit_item' => __('Edit Discount', '2download-connector'),
				'new_item' => __('New Discount', '2download-connector'),
				'view_item' => __('View Discount', '2download-connector'),
				'search_items' => __('Search Discounts', '2download-connector'),
				'not_found' => __('No discounts found.', '2download-connector'),
				'not_found_in_trash' => __('No discounts found in Trash.', '2download-connector'),
				'all_items' => __('Discount Codes', '2download-connector'),
			],
			'public' => false,
			'show_ui' => true,
			'show_in_menu' => 'ToDownload_seller',
			'supports' => ['title', 'author'],
			'capability_type' => 'todownload_discount',
			'map_meta_cap' => true,
			'show_in_rest' => true,
			'menu_position' => 58,
		]);
	}

	public static function register_metaboxes(): void {
		add_meta_box(
			'ToDownload_discount_settings',
			__('Discount Settings', '2download-connector'),
			[self::class, 'render_metabox'],
			self::POST_TYPE,
			'normal',
			'default'
		);
	}

	private static function meta_int(int $post_id, string $key): int {
		return (int) get_post_meta($post_id, $key, true);
	}

	private static function meta_str(int $post_id, string $key): string {
		return (string) get_post_meta($post_id, $key, true);
	}

	public static function render_metabox($post): void {
		wp_nonce_field('ToDownload_discount_save', 'ToDownload_discount_nonce');

		$code = self::meta_str($post->ID, '_ToDownload_discount_code');
		$apply_mode = self::meta_str($post->ID, '_ToDownload_discount_apply_mode') ?: 'code';
		$type = self::meta_str($post->ID, '_ToDownload_discount_type') ?: 'percent';
		$amount = self::meta_str($post->ID, '_ToDownload_discount_amount');
		$min_subtotal = self::meta_str($post->ID, '_ToDownload_discount_min_subtotal');
		$min_quantity = self::meta_int($post->ID, '_ToDownload_discount_min_quantity');
		$max_discount = self::meta_str($post->ID, '_ToDownload_discount_max_discount');
		$cart_rule = self::meta_str($post->ID, '_ToDownload_discount_cart_rule');
		$rule_quantity_basis = self::meta_str($post->ID, '_ToDownload_discount_rule_quantity_basis') ?: 'eligible';
		$tier_rules_text = self::meta_str($post->ID, '_ToDownload_discount_tier_rules_text');
		$cheapest_item_quantity = self::meta_int($post->ID, '_ToDownload_discount_cheapest_item_quantity');
		$cheapest_item_percent_off = self::meta_str($post->ID, '_ToDownload_discount_cheapest_item_percent_off');
		$bundle_set_quantity = self::meta_int($post->ID, '_ToDownload_discount_bundle_set_quantity');
		$bogo_buy_quantity = self::meta_int($post->ID, '_ToDownload_discount_bogo_buy_quantity');
		$bogo_get_quantity = self::meta_int($post->ID, '_ToDownload_discount_bogo_get_quantity');
		$bogo_get_percent_off = self::meta_str($post->ID, '_ToDownload_discount_bogo_get_percent_off');
		$product_ids = self::meta_str($post->ID, '_ToDownload_discount_product_ids');
		$selected_ids = self::parse_ids_csv($product_ids);
		$excluded_product_ids = self::meta_str($post->ID, '_ToDownload_discount_excluded_product_ids');
		$selected_excluded_ids = self::parse_ids_csv($excluded_product_ids);
		$required_prior_product_ids = self::meta_str($post->ID, '_ToDownload_discount_required_prior_product_ids');
		$selected_required_prior_ids = self::parse_ids_csv($required_prior_product_ids);
		$allowed_customer_emails = self::meta_str($post->ID, '_ToDownload_discount_allowed_customer_emails');
		$usage_limit = self::meta_int($post->ID, '_ToDownload_discount_usage_limit');
		$usage_limit_per_customer = self::meta_int($post->ID, '_ToDownload_discount_usage_limit_per_customer');
		$usage_count = self::meta_int($post->ID, '_ToDownload_discount_usage_count');
		$expires = self::meta_str($post->ID, '_ToDownload_discount_expires');
		$returning_only = self::meta_int($post->ID, '_ToDownload_discount_returning_customers_only') === 1;
		$first_time_only = self::meta_int($post->ID, '_ToDownload_discount_first_time_customers_only') === 1;
		$eligibility = $returning_only ? 'returning' : ($first_time_only ? 'first_time' : 'any');

		?>
		<p>
			<label><strong><?php esc_html_e('Code', '2download-connector'); ?></strong></label><br />
			<input type="text" name="ToDownload_discount_code" value="<?php echo esc_attr($code); ?>" class="regular-text" placeholder="SAVE10" />
			<br /><small><?php esc_html_e('Customers enter this at checkout.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Type', '2download-connector'); ?></strong></label><br />
			<select name="ToDownload_discount_type" id="ToDownload_discount_type">
				<option value="percent" <?php selected($type, 'percent'); ?>><?php esc_html_e('Percent', '2download-connector'); ?></option>
				<option value="flat" <?php selected($type, 'flat'); ?>><?php esc_html_e('Flat amount', '2download-connector'); ?></option>
				<option value="fixed_price" <?php selected($type, 'fixed_price'); ?>><?php esc_html_e('Fixed price', '2download-connector'); ?></option>
				<option value="bogo" <?php selected($type, 'bogo'); ?>><?php esc_html_e('BOGO (buy X get Y)', '2download-connector'); ?></option>
			</select>
		</p>
		<p>
			<label><strong><?php esc_html_e('Apply mode', '2download-connector'); ?></strong></label><br />
			<select name="ToDownload_discount_apply_mode" id="ToDownload_discount_apply_mode">
				<option value="code" <?php selected($apply_mode, 'code'); ?>><?php esc_html_e('Code (requires entry)', '2download-connector'); ?></option>
				<option value="auto" <?php selected($apply_mode, 'auto'); ?>><?php esc_html_e('Auto-apply (best discount)', '2download-connector'); ?></option>
			</select>
		</p>
		<p id="ToDownload_discount_amount_wrap">
			<label><strong><span id="ToDownload_discount_amount_label"><?php echo esc_html($type === 'flat' ? __('Amount', '2download-connector') : ($type === 'fixed_price' ? __('Fixed price', '2download-connector') : __('Percentage', '2download-connector'))); ?></span></strong></label><br />
			<input type="number" step="0.01" min="0" name="ToDownload_discount_amount" value="<?php echo esc_attr($amount); ?>" />
			<br /><small id="ToDownload_discount_amount_help"><?php echo esc_html($type === 'flat' ? __('Flat amount in USD (e.g. 5).', '2download-connector') : ($type === 'fixed_price' ? __('Buyer pays this price in USD (e.g. 10).', '2download-connector') : __('Percent (e.g. 10 for 10%).', '2download-connector'))); ?></small>
		</p>
		<p id="ToDownload_discount_bogo_fields" style="display:none;">
			<label><strong><?php esc_html_e('BOGO settings', '2download-connector'); ?></strong></label><br />
			<input type="number" min="1" step="1" name="ToDownload_discount_bogo_buy_quantity" value="<?php echo esc_attr((string) max(1, (int) $bogo_buy_quantity)); ?>" style="width:100px;" />
			<span><?php esc_html_e('buy', '2download-connector'); ?></span>
			<input type="number" min="1" step="1" name="ToDownload_discount_bogo_get_quantity" value="<?php echo esc_attr((string) max(1, (int) $bogo_get_quantity)); ?>" style="width:100px; margin-left:8px;" />
			<span><?php esc_html_e('get', '2download-connector'); ?></span>
			<br />
			<label style="display:block; margin-top:8px;"><strong><?php esc_html_e('Get percent off', '2download-connector'); ?></strong></label>
			<input type="number" min="0" max="100" step="0.01" name="ToDownload_discount_bogo_get_percent_off" value="<?php echo esc_attr($bogo_get_percent_off !== '' ? $bogo_get_percent_off : '100'); ?>" style="width:120px;" />
			<br /><small><?php esc_html_e('Discount applies to the cheapest eligible items in each (buy+get) set.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Min subtotal (optional)', '2download-connector'); ?></strong></label><br />
			<input type="number" step="0.01" min="0" name="ToDownload_discount_min_subtotal" value="<?php echo esc_attr($min_subtotal); ?>" />
			<br /><small><?php esc_html_e('Minimum subtotal in USD (e.g. 20). Leave blank for no minimum.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Min quantity (optional)', '2download-connector'); ?></strong></label><br />
			<input type="number" step="1" min="1" name="ToDownload_discount_min_quantity" value="<?php echo esc_attr($min_quantity > 0 ? (string) $min_quantity : ''); ?>" />
			<br /><small><?php esc_html_e('Minimum number of eligible items required in cart. Leave blank for no minimum.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Max discount (optional)', '2download-connector'); ?></strong></label><br />
			<input type="number" step="0.01" min="0" name="ToDownload_discount_max_discount" value="<?php echo esc_attr($max_discount); ?>" />
			<br /><small><?php esc_html_e('Maximum discount in USD (e.g. 15). Leave blank for no cap.', '2download-connector'); ?></small>
		</p>
		<p id="ToDownload_discount_cart_rule_wrap">
			<label><strong><?php esc_html_e('Cart rule (optional)', '2download-connector'); ?></strong></label><br />
			<select name="ToDownload_discount_cart_rule" id="ToDownload_discount_cart_rule">
				<option value="" <?php selected($cart_rule, ''); ?>><?php esc_html_e('None', '2download-connector'); ?></option>
				<option value="tiered" <?php selected($cart_rule, 'tiered'); ?>><?php esc_html_e('Tiered / volume', '2download-connector'); ?></option>
				<option value="cheapest" <?php selected($cart_rule, 'cheapest'); ?>><?php esc_html_e('Cheapest item(s) % off', '2download-connector'); ?></option>
				<option value="bundle" <?php selected($cart_rule, 'bundle'); ?>><?php esc_html_e('Bundle / set price', '2download-connector'); ?></option>
			</select>
			<br /><small><?php esc_html_e('Adds cart-based rules (tiered, cheapest item, bundle pricing). Cannot be combined with BOGO.', '2download-connector'); ?></small>
		</p>
		<p id="ToDownload_discount_rule_basis_wrap" style="display:none;">
			<label><strong><?php esc_html_e('Rule quantity basis', '2download-connector'); ?></strong></label><br />
			<select name="ToDownload_discount_rule_quantity_basis" id="ToDownload_discount_rule_quantity_basis">
				<option value="eligible" <?php selected($rule_quantity_basis, 'eligible'); ?>><?php esc_html_e('Eligible items only', '2download-connector'); ?></option>
				<option value="total" <?php selected($rule_quantity_basis, 'total'); ?>><?php esc_html_e('Total cart items', '2download-connector'); ?></option>
			</select>
			<br /><small><?php esc_html_e('Controls how tier thresholds / bundle sets are counted. Discount still applies only to eligible items.', '2download-connector'); ?></small>
		</p>
		<div id="ToDownload_discount_tiered_fields" style="display:none;">
			<p>
				<label><strong><?php esc_html_e('Tier rules', '2download-connector'); ?></strong></label><br />
				<textarea name="ToDownload_discount_tier_rules_text" rows="5" style="width:100%; max-width:520px;" placeholder="2: 10\n5: 15"><?php echo esc_textarea($tier_rules_text); ?></textarea>
				<br /><small><?php esc_html_e('One tier per line: min_qty: value. For Percent, value is % (e.g. 10). For Flat amount, value is USD (e.g. 5).', '2download-connector'); ?></small>
			</p>
		</div>
		<div id="ToDownload_discount_cheapest_fields" style="display:none;">
			<p>
				<label><strong><?php esc_html_e('Cheapest item rule', '2download-connector'); ?></strong></label><br />
				<input type="number" min="1" step="1" name="ToDownload_discount_cheapest_item_quantity" value="<?php echo esc_attr($cheapest_item_quantity > 0 ? (string) $cheapest_item_quantity : ''); ?>" style="width:120px;" />
				<span><?php esc_html_e('cheapest items get', '2download-connector'); ?></span>
				<input type="number" min="0" max="100" step="0.01" name="ToDownload_discount_cheapest_item_percent_off" value="<?php echo esc_attr($cheapest_item_percent_off !== '' ? $cheapest_item_percent_off : ''); ?>" style="width:140px; margin-left:8px;" />
				<span>%</span>
				<br /><small><?php esc_html_e('Requires Type = Percent. Applies to the cheapest eligible units.', '2download-connector'); ?></small>
			</p>
		</div>
		<div id="ToDownload_discount_bundle_fields" style="display:none;">
			<p>
				<label><strong><?php esc_html_e('Bundle rule', '2download-connector'); ?></strong></label><br />
				<input type="number" min="1" step="1" name="ToDownload_discount_bundle_set_quantity" value="<?php echo esc_attr($bundle_set_quantity > 0 ? (string) $bundle_set_quantity : ''); ?>" style="width:140px;" />
				<span><?php esc_html_e('items per set', '2download-connector'); ?></span>
				<br /><small><?php esc_html_e('Requires Type = Fixed price. “Fixed price” above is the price per set.', '2download-connector'); ?></small>
			</p>
		</div>
		<p>
			<label><strong><?php esc_html_e('Applies to products (optional)', '2download-connector'); ?></strong></label><br />
			<input type="search" id="ToDownload_discount_product_search" class="regular-text" placeholder="<?php echo esc_attr__('Search products…', '2download-connector'); ?>" style="max-width:420px;" />
			<br />
			<select id="ToDownload_discount_product_select" name="ToDownload_discount_product_ids[]" multiple size="8" style="width:100%; max-width:420px;">
				<?php
				$products = get_posts([
					'post_type' => DownloadPostType::POST_TYPE,
					'post_status' => ['publish', 'draft', 'pending', 'private'],
					'posts_per_page' => 200,
					'orderby' => 'title',
					'order' => 'ASC',
					'fields' => 'ids',
				]);
				if (!is_array($products)) {
					$products = [];
				}
				if (empty($products)) {
					echo '<option disabled>' . esc_html__('No products found.', '2download-connector') . '</option>';
				} else {
					foreach ($products as $pid) {
						$pid = (int) $pid;
						$title = get_the_title($pid);
						$label = $title !== '' ? $title : ('#' . $pid);
						echo '<option value="' . esc_attr((string) $pid) . '" ' . selected(in_array($pid, $selected_ids, true), true, false) . '>'
							. esc_html($label)
							. '</option>';
					}
				}
				?>
			</select>
			<br /><small><?php esc_html_e('Leave blank to apply to any product in the cart. Hold ⌘/Ctrl to select multiple.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Exclude products (optional)', '2download-connector'); ?></strong></label><br />
			<input type="search" id="ToDownload_discount_excluded_product_search" class="regular-text" placeholder="<?php echo esc_attr__('Search products…', '2download-connector'); ?>" style="max-width:420px;" />
			<br />
			<select id="ToDownload_discount_excluded_product_select" name="ToDownload_discount_excluded_product_ids[]" multiple size="8" style="width:100%; max-width:420px;">
				<?php
				if (empty($products)) {
					echo '<option disabled>' . esc_html__('No products found.', '2download-connector') . '</option>';
				} else {
					foreach ($products as $pid) {
						$pid = (int) $pid;
						$title = get_the_title($pid);
						$label = $title !== '' ? $title : ('#' . $pid);
						echo '<option value="' . esc_attr((string) $pid) . '" ' . selected(in_array($pid, $selected_excluded_ids, true), true, false) . '>'
							. esc_html($label)
							. '</option>';
					}
				}
				?>
			</select>
			<br /><small><?php esc_html_e('If the discount would otherwise apply, these products are excluded.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Requires prior purchase of products (optional)', '2download-connector'); ?></strong></label><br />
			<input type="search" id="ToDownload_discount_required_prior_product_search" class="regular-text" placeholder="<?php echo esc_attr__('Search products…', '2download-connector'); ?>" style="max-width:420px;" />
			<br />
			<select id="ToDownload_discount_required_prior_product_select" name="ToDownload_discount_required_prior_product_ids[]" multiple size="8" style="width:100%; max-width:420px;">
				<?php
				if (empty($products)) {
					echo '<option disabled>' . esc_html__('No products found.', '2download-connector') . '</option>';
				} else {
					foreach ($products as $pid) {
						$pid = (int) $pid;
						$title = get_the_title($pid);
						$label = $title !== '' ? $title : ('#' . $pid);
						echo '<option value="' . esc_attr((string) $pid) . '" ' . selected(in_array($pid, $selected_required_prior_ids, true), true, false) . '>'
							. esc_html($label)
							. '</option>';
					}
				}
				?>
			</select>
			<br /><small><?php esc_html_e('Buyer must have a prior paid order for at least one selected product. This requires a buyer email.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Allowed customers (optional)', '2download-connector'); ?></strong></label><br />
			<textarea name="ToDownload_discount_allowed_customer_emails" rows="5" class="large-text" placeholder="one@email.com\nother@email.com"><?php echo esc_textarea($allowed_customer_emails); ?></textarea>
			<br /><small><?php esc_html_e('One email per line (or comma-separated). If set, buyer email is required.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Usage limit (optional)', '2download-connector'); ?></strong></label><br />
			<input type="number" min="0" name="ToDownload_discount_usage_limit" value="<?php echo esc_attr((string) $usage_limit); ?>" />
			<br /><small><?php esc_html_e('0 means unlimited.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Per-customer usage limit (optional)', '2download-connector'); ?></strong></label><br />
			<input type="number" min="0" name="ToDownload_discount_usage_limit_per_customer" value="<?php echo esc_attr((string) $usage_limit_per_customer); ?>" />
			<br /><small><?php esc_html_e('0 means unlimited per customer.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Customer eligibility (optional)', '2download-connector'); ?></strong></label><br />
			<select name="ToDownload_discount_customer_eligibility" id="ToDownload_discount_customer_eligibility">
				<option value="any" <?php selected($eligibility, 'any'); ?>><?php esc_html_e('Any customer', '2download-connector'); ?></option>
				<option value="returning" <?php selected($eligibility, 'returning'); ?>><?php esc_html_e('Returning customers only', '2download-connector'); ?></option>
				<option value="first_time" <?php selected($eligibility, 'first_time'); ?>><?php esc_html_e('First-time customers only', '2download-connector'); ?></option>
			</select>
			<br /><small><?php esc_html_e('These rules require a buyer email at checkout.', '2download-connector'); ?></small>
		</p>
		<p>
			<label><strong><?php esc_html_e('Expires (optional)', '2download-connector'); ?></strong></label><br />
			<span class="todownload-datepicker-wrap">
				<input type="text" name="ToDownload_discount_expires" class="todownload-datepicker" value="<?php echo esc_attr($expires); ?>" placeholder="YYYY-MM-DD" autocomplete="off" />
				<button type="button" class="button todownload-datepicker-trigger" aria-label="<?php echo esc_attr__('Pick a date', '2download-connector'); ?>">
					<span class="dashicons dashicons-calendar-alt" aria-hidden="true"></span>
				</button>
			</span>
		</p>
		<p>
			<strong><?php esc_html_e('Usage count', '2download-connector'); ?></strong>: <?php echo esc_html((string) $usage_count); ?>
		</p>
		<?php
	}

	public static function save_metabox(int $post_id, \WP_Post $post): void {
		$post_data = wp_unslash($_POST);
		$nonce = isset($post_data['ToDownload_discount_nonce']) ? sanitize_text_field((string) $post_data['ToDownload_discount_nonce']) : '';
		if (!$nonce || !wp_verify_nonce($nonce, 'ToDownload_discount_save')) {
			return;
		}
		if (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) {
			return;
		}
		if (wp_is_post_revision($post_id)) {
			return;
		}
		if (!current_user_can('edit_post', $post_id)) {
			return;
		}

		$code = strtoupper(sanitize_text_field((string) ($post_data['ToDownload_discount_code'] ?? '')));
		$apply_mode = sanitize_text_field((string) ($post_data['ToDownload_discount_apply_mode'] ?? 'code'));
		$type = sanitize_text_field((string) ($post_data['ToDownload_discount_type'] ?? 'percent'));
		$amount = sanitize_text_field((string) ($post_data['ToDownload_discount_amount'] ?? '0'));
		$min_subtotal = sanitize_text_field((string) ($post_data['ToDownload_discount_min_subtotal'] ?? ''));
		$min_quantity = isset($post_data['ToDownload_discount_min_quantity']) ? absint($post_data['ToDownload_discount_min_quantity']) : 0;
		$max_discount = sanitize_text_field((string) ($post_data['ToDownload_discount_max_discount'] ?? ''));
		$bogo_buy_quantity = isset($post_data['ToDownload_discount_bogo_buy_quantity']) ? absint($post_data['ToDownload_discount_bogo_buy_quantity']) : 0;
		$bogo_get_quantity = isset($post_data['ToDownload_discount_bogo_get_quantity']) ? absint($post_data['ToDownload_discount_bogo_get_quantity']) : 0;
		$bogo_get_percent_off = sanitize_text_field((string) ($post_data['ToDownload_discount_bogo_get_percent_off'] ?? ''));
		$cart_rule = sanitize_text_field((string) ($post_data['ToDownload_discount_cart_rule'] ?? ''));
		$rule_quantity_basis = sanitize_text_field((string) ($post_data['ToDownload_discount_rule_quantity_basis'] ?? 'eligible'));
		$tier_rules_text = isset($post_data['ToDownload_discount_tier_rules_text'])
			? sanitize_textarea_field((string) $post_data['ToDownload_discount_tier_rules_text'])
			: '';
		$cheapest_item_quantity = isset($post_data['ToDownload_discount_cheapest_item_quantity']) ? absint($post_data['ToDownload_discount_cheapest_item_quantity']) : 0;
		$cheapest_item_percent_off = sanitize_text_field((string) ($post_data['ToDownload_discount_cheapest_item_percent_off'] ?? ''));
		$bundle_set_quantity = isset($post_data['ToDownload_discount_bundle_set_quantity']) ? absint($post_data['ToDownload_discount_bundle_set_quantity']) : 0;
		$product_ids_raw = $post_data['ToDownload_discount_product_ids'] ?? '';
		$product_ids = '';
		if (is_array($product_ids_raw)) {
			$ids = array_values(array_filter(array_map('intval', $product_ids_raw)));
			$ids = array_values(array_unique(array_filter($ids, fn($id) => $id > 0)));
			$product_ids = implode(',', $ids);
		} else {
			$product_ids = sanitize_text_field((string) $product_ids_raw);
		}
		$usage_limit = isset($post_data['ToDownload_discount_usage_limit']) ? absint($post_data['ToDownload_discount_usage_limit']) : 0;
		$usage_limit_per_customer = isset($post_data['ToDownload_discount_usage_limit_per_customer']) ? absint($post_data['ToDownload_discount_usage_limit_per_customer']) : 0;
		$eligibility = sanitize_text_field((string) ($post_data['ToDownload_discount_customer_eligibility'] ?? 'any'));
		$expires = sanitize_text_field((string) ($post_data['ToDownload_discount_expires'] ?? ''));

		$excluded_product_ids_raw = $post_data['ToDownload_discount_excluded_product_ids'] ?? '';
		$excluded_product_ids = '';
		if (is_array($excluded_product_ids_raw)) {
			$ids = array_values(array_filter(array_map('intval', $excluded_product_ids_raw)));
			$ids = array_values(array_unique(array_filter($ids, fn($id) => $id > 0)));
			$excluded_product_ids = implode(',', $ids);
		} else {
			$excluded_product_ids = sanitize_text_field((string) $excluded_product_ids_raw);
		}

		$required_prior_product_ids_raw = $post_data['ToDownload_discount_required_prior_product_ids'] ?? '';
		$required_prior_product_ids = '';
		if (is_array($required_prior_product_ids_raw)) {
			$ids = array_values(array_filter(array_map('intval', $required_prior_product_ids_raw)));
			$ids = array_values(array_unique(array_filter($ids, fn($id) => $id > 0)));
			$required_prior_product_ids = implode(',', $ids);
		} else {
			$required_prior_product_ids = sanitize_text_field((string) $required_prior_product_ids_raw);
		}

		$allowed_customer_emails = isset($post_data['ToDownload_discount_allowed_customer_emails'])
			? sanitize_textarea_field((string) $post_data['ToDownload_discount_allowed_customer_emails'])
			: '';

		update_post_meta($post_id, '_ToDownload_discount_code', $code);
		update_post_meta($post_id, '_ToDownload_discount_apply_mode', in_array($apply_mode, ['code', 'auto'], true) ? $apply_mode : 'code');
		update_post_meta($post_id, '_ToDownload_discount_type', in_array($type, ['percent', 'flat', 'fixed_price', 'bogo'], true) ? $type : 'percent');
		update_post_meta($post_id, '_ToDownload_discount_amount', $amount);
		update_post_meta($post_id, '_ToDownload_discount_min_subtotal', $min_subtotal);
		update_post_meta($post_id, '_ToDownload_discount_min_quantity', $min_quantity);
		update_post_meta($post_id, '_ToDownload_discount_max_discount', $max_discount);
		update_post_meta($post_id, '_ToDownload_discount_bogo_buy_quantity', $bogo_buy_quantity);
		update_post_meta($post_id, '_ToDownload_discount_bogo_get_quantity', $bogo_get_quantity);
		update_post_meta($post_id, '_ToDownload_discount_bogo_get_percent_off', $bogo_get_percent_off);
		update_post_meta($post_id, '_ToDownload_discount_cart_rule', in_array($cart_rule, ['tiered', 'cheapest', 'bundle'], true) ? $cart_rule : '');
		update_post_meta($post_id, '_ToDownload_discount_rule_quantity_basis', in_array($rule_quantity_basis, ['eligible', 'total'], true) ? $rule_quantity_basis : 'eligible');
		update_post_meta($post_id, '_ToDownload_discount_tier_rules_text', $tier_rules_text);
		update_post_meta($post_id, '_ToDownload_discount_cheapest_item_quantity', $cheapest_item_quantity);
		update_post_meta($post_id, '_ToDownload_discount_cheapest_item_percent_off', $cheapest_item_percent_off);
		update_post_meta($post_id, '_ToDownload_discount_bundle_set_quantity', $bundle_set_quantity);
		update_post_meta($post_id, '_ToDownload_discount_product_ids', $product_ids);
		update_post_meta($post_id, '_ToDownload_discount_excluded_product_ids', $excluded_product_ids);
		update_post_meta($post_id, '_ToDownload_discount_required_prior_product_ids', $required_prior_product_ids);
		update_post_meta($post_id, '_ToDownload_discount_allowed_customer_emails', $allowed_customer_emails);
		update_post_meta($post_id, '_ToDownload_discount_usage_limit', $usage_limit);
		update_post_meta($post_id, '_ToDownload_discount_usage_limit_per_customer', $usage_limit_per_customer);
		update_post_meta($post_id, '_ToDownload_discount_returning_customers_only', $eligibility === 'returning' ? 1 : 0);
		update_post_meta($post_id, '_ToDownload_discount_first_time_customers_only', $eligibility === 'first_time' ? 1 : 0);
		update_post_meta($post_id, '_ToDownload_discount_expires', $expires);

		// Sync to hosted platform so 2dl.app is the canonical discount system.
		self::sync_discount_to_hosted((int) $post_id, $post, [
			'code' => $code,
			'apply_mode' => $apply_mode,
			'type' => $type,
			'amount' => $amount,
			'min_subtotal' => $min_subtotal,
			'min_quantity' => (string) $min_quantity,
			'max_discount' => $max_discount,
			'bogo_buy_quantity' => (string) $bogo_buy_quantity,
			'bogo_get_quantity' => (string) $bogo_get_quantity,
			'bogo_get_percent_off' => $bogo_get_percent_off,
			'cart_rule' => $cart_rule,
			'rule_quantity_basis' => $rule_quantity_basis,
			'tier_rules_text' => $tier_rules_text,
			'cheapest_item_quantity' => $cheapest_item_quantity,
			'cheapest_item_percent_off' => $cheapest_item_percent_off,
			'bundle_set_quantity' => $bundle_set_quantity,
			'usage_limit' => $usage_limit,
			'usage_limit_per_customer' => $usage_limit_per_customer,
			'customer_eligibility' => $eligibility,
			'expires' => $expires,
		], null);
	}

	private static function parse_emails_text(string $raw): array {
		$raw = trim($raw);
		if ($raw === '') {
			return [];
		}
		$raw = str_replace("\r", "\n", $raw);
		$parts = preg_split('/\n|,/', $raw);
		if (!is_array($parts)) {
			return [];
		}
		$out = [];
		$seen = [];
		foreach ($parts as $p) {
			$e = strtolower(trim((string) $p));
			if ($e === '' || !is_email($e)) {
				continue;
			}
			if (isset($seen[$e])) {
				continue;
			}
			$seen[$e] = true;
			$out[] = $e;
			if (count($out) >= 500) {
				break;
			}
		}
		return $out;
	}

	/**
	 * @param int[] $wp_download_ids
	 * @return array<int,string> Map of wp_download_id => hosted product publicId
	 */
	private static function hosted_public_id_map_for_wp_download_ids(string $hosted_base, string $store_public_id, string $api_key, string $request_id, array $wp_download_ids): array {
		$wp_download_ids = array_values(array_unique(array_filter(array_map('intval', $wp_download_ids), fn($id) => $id > 0)));
		if (empty($wp_download_ids)) {
			return [];
		}

		$hosted_products = [];
		$products_res = HostedClient::get_json(
			$hosted_base,
			'/api/v1/stores/' . rawurlencode($store_public_id) . '/products',
			$api_key,
			$request_id
		);
		if (!empty($products_res['ok']) && isset($products_res['data']) && is_array($products_res['data'])) {
			$hosted_products = is_array($products_res['data']['products'] ?? null) ? (array) $products_res['data']['products'] : [];
		}

		$external_to_public = [];
		foreach ($hosted_products as $p) {
			if (!is_array($p)) {
				continue;
			}
			$ext = isset($p['externalId']) ? (string) $p['externalId'] : '';
			$pub = isset($p['publicId']) ? (string) $p['publicId'] : '';
			$ext = trim($ext);
			$pub = trim($pub);
			if ($ext !== '' && $pub !== '') {
				$external_to_public[$ext] = $pub;
			}
		}

		$out = [];
		foreach ($wp_download_ids as $wp_download_id) {
			$wp_download_id = (int) $wp_download_id;
			$external_id = 'wp_download_' . (string) $wp_download_id;
			if (isset($external_to_public[$external_id])) {
				$out[$wp_download_id] = (string) $external_to_public[$external_id];
				continue;
			}

			$title = get_the_title($wp_download_id);
			$name = is_string($title) && trim($title) !== '' ? trim($title) : ('WP Download #' . (string) $wp_download_id);
			$price_raw = (string) get_post_meta($wp_download_id, '_ToDownload_price', true);
			$price = (float) $price_raw;
			$amount_minor = (int) round(max(0.0, $price) * 100);
			if ($amount_minor <= 0) {
				continue;
			}

			$create_res = HostedClient::post_json(
				$hosted_base,
				'/api/v1/stores/' . rawurlencode($store_public_id) . '/products',
				[
					'external_id' => $external_id,
					'name' => $name,
					'currency' => 'usd',
					'amount_minor' => $amount_minor,
					'status' => 'active',
				],
				$api_key,
				$request_id
			);
			if (!empty($create_res['ok']) && isset($create_res['product']) && is_array($create_res['product'])) {
				$created = (array) $create_res['product'];
				$pub = isset($created['public_id']) ? trim((string) $created['public_id']) : '';
				if ($pub !== '') {
					$out[$wp_download_id] = $pub;
					$external_to_public[$external_id] = $pub;
				}
			}
		}

		return $out;
	}

	/**
	 * @param array{code:string,apply_mode?:string,type:string,amount:string,min_subtotal?:string,min_quantity?:string,max_discount?:string,bogo_buy_quantity?:string,bogo_get_quantity?:string,bogo_get_percent_off?:string,cart_rule?:string,rule_quantity_basis?:string,tier_rules_text?:string,cheapest_item_quantity?:int,cheapest_item_percent_off?:string,bundle_set_quantity?:int,usage_limit:int,usage_limit_per_customer?:int,customer_eligibility?:string,expires:string}|null $data
	 */
	private static function sync_discount_to_hosted(int $post_id, \WP_Post $post, ?array $data, ?string $force_status): void {
		$code = '';
		if (is_array($data) && isset($data['code'])) {
			$code = strtoupper(trim((string) $data['code']));
		}
		if ($code === '') {
			$code = (string) get_post_meta($post_id, '_ToDownload_discount_code', true);
			$code = strtoupper(trim($code));
		}
		if ($code === '') {
			return;
		}

		$seller_user_id = (int) ($post->post_author ?? 0);
		if ($seller_user_id <= 0) {
			return;
		}

		$hosted = Sellers::hosted_credentials($seller_user_id);
		if (empty($hosted['connected']) || empty($hosted['store_public_id']) || empty($hosted['api_key'])) {
			return;
		}

		$hosted_base = (string) ($hosted['hosted_base'] ?? 'https://2dl.app');
		$hosted_base = $hosted_base !== '' ? rtrim($hosted_base, '/') : 'https://2dl.app';
		$store_public_id = trim((string) ($hosted['store_public_id'] ?? ''));
		$api_key = trim((string) ($hosted['api_key'] ?? ''));
		if ($store_public_id === '' || $api_key === '') {
			return;
		}

		$apply_mode = is_array($data) ? (string) ($data['apply_mode'] ?? '') : '';
		$type = is_array($data) ? (string) ($data['type'] ?? '') : '';
		$amount = is_array($data) ? (string) ($data['amount'] ?? '') : '';
		$min_subtotal = is_array($data) ? (string) ($data['min_subtotal'] ?? '') : '';
		$min_quantity = is_array($data) ? (string) ($data['min_quantity'] ?? '') : '';
		$max_discount = is_array($data) ? (string) ($data['max_discount'] ?? '') : '';
		$bogo_buy_quantity = is_array($data) ? (string) ($data['bogo_buy_quantity'] ?? '') : '';
		$bogo_get_quantity = is_array($data) ? (string) ($data['bogo_get_quantity'] ?? '') : '';
		$bogo_get_percent_off = is_array($data) ? (string) ($data['bogo_get_percent_off'] ?? '') : '';
		$cart_rule = is_array($data) ? (string) ($data['cart_rule'] ?? '') : '';
		$rule_quantity_basis = is_array($data) ? (string) ($data['rule_quantity_basis'] ?? '') : '';
		$tier_rules_text = is_array($data) ? (string) ($data['tier_rules_text'] ?? '') : '';
		$cheapest_item_quantity = is_array($data) ? (int) ($data['cheapest_item_quantity'] ?? 0) : 0;
		$cheapest_item_percent_off = is_array($data) ? (string) ($data['cheapest_item_percent_off'] ?? '') : '';
		$bundle_set_quantity = is_array($data) ? (int) ($data['bundle_set_quantity'] ?? 0) : 0;
		$usage_limit = is_array($data) ? (int) ($data['usage_limit'] ?? 0) : 0;
		$usage_limit_per_customer = is_array($data) ? (int) ($data['usage_limit_per_customer'] ?? 0) : 0;
		$customer_eligibility = is_array($data) ? (string) ($data['customer_eligibility'] ?? '') : '';
		$expires = is_array($data) ? trim((string) ($data['expires'] ?? '')) : '';
		if ($type === '' || $amount === '') {
			$apply_mode = (string) get_post_meta($post_id, '_ToDownload_discount_apply_mode', true);
			$type = (string) get_post_meta($post_id, '_ToDownload_discount_type', true);
			$amount = (string) get_post_meta($post_id, '_ToDownload_discount_amount', true);
			$min_subtotal = (string) get_post_meta($post_id, '_ToDownload_discount_min_subtotal', true);
			$min_quantity = (string) get_post_meta($post_id, '_ToDownload_discount_min_quantity', true);
			$max_discount = (string) get_post_meta($post_id, '_ToDownload_discount_max_discount', true);
			$bogo_buy_quantity = (string) get_post_meta($post_id, '_ToDownload_discount_bogo_buy_quantity', true);
			$bogo_get_quantity = (string) get_post_meta($post_id, '_ToDownload_discount_bogo_get_quantity', true);
			$bogo_get_percent_off = (string) get_post_meta($post_id, '_ToDownload_discount_bogo_get_percent_off', true);
			$cart_rule = (string) get_post_meta($post_id, '_ToDownload_discount_cart_rule', true);
			$rule_quantity_basis = (string) get_post_meta($post_id, '_ToDownload_discount_rule_quantity_basis', true);
			$tier_rules_text = (string) get_post_meta($post_id, '_ToDownload_discount_tier_rules_text', true);
			$cheapest_item_quantity = (int) get_post_meta($post_id, '_ToDownload_discount_cheapest_item_quantity', true);
			$cheapest_item_percent_off = (string) get_post_meta($post_id, '_ToDownload_discount_cheapest_item_percent_off', true);
			$bundle_set_quantity = (int) get_post_meta($post_id, '_ToDownload_discount_bundle_set_quantity', true);
			$usage_limit = (int) get_post_meta($post_id, '_ToDownload_discount_usage_limit', true);
			$usage_limit_per_customer = (int) get_post_meta($post_id, '_ToDownload_discount_usage_limit_per_customer', true);
			$customer_eligibility = (string) get_post_meta($post_id, '_ToDownload_discount_returning_customers_only', true) === '1'
				? 'returning'
				: (((string) get_post_meta($post_id, '_ToDownload_discount_first_time_customers_only', true) === '1') ? 'first_time' : 'any');
			$expires = (string) get_post_meta($post_id, '_ToDownload_discount_expires', true);
		}
		if (!in_array($apply_mode, ['code', 'auto'], true)) {
			$apply_mode = 'code';
		}
		if (!in_array($type, ['percent', 'flat', 'fixed_price', 'bogo'], true)) {
			$type = 'percent';
		}
		$amount_f = (float) $amount;
		$min_subtotal_f = (float) $min_subtotal;
		$min_quantity_i = (int) $min_quantity;
		$max_discount_f = (float) $max_discount;
		$bogo_buy_i = (int) $bogo_buy_quantity;
		$bogo_get_i = (int) $bogo_get_quantity;
		$bogo_pct_f = (float) $bogo_get_percent_off;

		$request_id = function_exists('wp_generate_uuid4') ? (string) wp_generate_uuid4() : (string) uniqid('2dl_', true);

		$payload = [
			'code' => $code,
			'status' => ($force_status === 'active' || $force_status === 'inactive')
				? $force_status
				: (($post->post_status === 'publish') ? 'active' : 'inactive'),
			'apply_mode' => $apply_mode,
		];

		// Product targeting: sync WP download selections to hosted product_public_ids.
		// We mirror WP downloads as hosted Products keyed by external_id = wp_download_{POST_ID}.
		$include_ids = self::parse_ids_csv((string) get_post_meta($post_id, '_ToDownload_discount_product_ids', true));
		$exclude_ids = self::parse_ids_csv((string) get_post_meta($post_id, '_ToDownload_discount_excluded_product_ids', true));
		$required_prior_ids = self::parse_ids_csv((string) get_post_meta($post_id, '_ToDownload_discount_required_prior_product_ids', true));
		$all = array_values(array_unique(array_merge($include_ids, $exclude_ids, $required_prior_ids)));
		$map = !empty($all) ? self::hosted_public_id_map_for_wp_download_ids($hosted_base, $store_public_id, $api_key, $request_id, $all) : [];

		$payload['product_public_ids'] = array_values(array_unique(array_values(array_filter(array_map(fn($id) => $map[(int) $id] ?? '', $include_ids)))));
		$payload['excluded_product_public_ids'] = array_values(array_unique(array_values(array_filter(array_map(fn($id) => $map[(int) $id] ?? '', $exclude_ids)))));
		$payload['required_prior_product_public_ids'] = array_values(array_unique(array_values(array_filter(array_map(fn($id) => $map[(int) $id] ?? '', $required_prior_ids)))));

		if ($type === 'bogo') {
			$payload['type'] = 'bogo';
			$payload['bogo_buy_quantity'] = max(1, $bogo_buy_i);
			$payload['bogo_get_quantity'] = max(1, $bogo_get_i);
			$payload['bogo_get_percent_off_bps'] = (int) round(max(0.0, min(100.0, $bogo_pct_f > 0 ? $bogo_pct_f : 100.0)) * 100);
		} else if ($type === 'flat') {
			$payload['type'] = 'amount';
			$payload['amount_off_minor'] = max(0, (int) round(max(0.0, $amount_f) * 100));
		} else if ($type === 'fixed_price') {
			$payload['type'] = 'fixed_price';
			$payload['fixed_price_minor'] = max(0, (int) round(max(0.0, $amount_f) * 100));
		} else {
			$payload['type'] = 'percent';
			$percent = max(0.0, min(100.0, $amount_f));
			$payload['percent_off_bps'] = (int) round($percent * 100);
		}

		if ($min_subtotal !== '') {
			$payload['min_subtotal_minor'] = max(0, (int) round(max(0.0, $min_subtotal_f) * 100));
		}

		if ($min_quantity_i > 0) {
			$payload['min_quantity'] = $min_quantity_i;
		}

		if ($max_discount !== '') {
			$payload['max_discount_minor'] = max(0, (int) round(max(0.0, $max_discount_f) * 100));
		}

		if ($usage_limit > 0) {
			$payload['usage_limit_total'] = $usage_limit;
		}

		if ($usage_limit_per_customer > 0) {
			$payload['usage_limit_per_customer'] = $usage_limit_per_customer;
		}

		if ($customer_eligibility === 'returning') {
			$payload['returning_customers_only'] = true;
			$payload['first_time_customers_only'] = false;
		} else if ($customer_eligibility === 'first_time') {
			$payload['returning_customers_only'] = false;
			$payload['first_time_customers_only'] = true;
		}

		if ($expires !== '') {
			try {
				$dt = new \DateTimeImmutable($expires . ' 23:59:59', new \DateTimeZone('UTC'));
				$payload['ends_at'] = $dt->format('c');
			} catch (\Exception $e) {
				// ignore invalid date
			}
		}

		// Cart rules (tiered / cheapest / bundle). These are optional and cannot be combined with BOGO.
		$cart_rule = trim((string) $cart_rule);
		if (!in_array($cart_rule, ['tiered', 'cheapest', 'bundle'], true)) {
			$cart_rule = '';
		}
		$rule_quantity_basis = trim((string) $rule_quantity_basis);
		if (!in_array($rule_quantity_basis, ['eligible', 'total'], true)) {
			$rule_quantity_basis = 'eligible';
		}

		if ($cart_rule !== '' && ($payload['type'] ?? '') !== 'bogo') {
			if ($cart_rule === 'tiered' && in_array((string) ($payload['type'] ?? ''), ['percent', 'amount'], true)) {
				$tiers = self::parse_tier_rules_text($tier_rules_text, (string) ($payload['type'] ?? ''));
				if (!empty($tiers)) {
					$payload['cart_rule'] = 'tiered';
					$payload['rule_quantity_basis'] = $rule_quantity_basis;
					$payload['tier_rules'] = $tiers;
				}
			} else if ($cart_rule === 'cheapest' && (string) ($payload['type'] ?? '') === 'percent') {
				$qty = max(0, (int) $cheapest_item_quantity);
				$pct = (float) $cheapest_item_percent_off;
				$bps = (int) round(max(0.0, min(100.0, $pct)) * 100);
				if ($qty > 0 && $bps > 0) {
					$payload['cart_rule'] = 'cheapest';
					$payload['rule_quantity_basis'] = $rule_quantity_basis;
					$payload['cheapest_item_quantity'] = $qty;
					$payload['cheapest_item_percent_off_bps'] = $bps;
				}
			} else if ($cart_rule === 'bundle' && (string) ($payload['type'] ?? '') === 'fixed_price') {
				$set_qty = max(0, (int) $bundle_set_quantity);
				if ($set_qty > 0) {
					$payload['cart_rule'] = 'bundle';
					$payload['rule_quantity_basis'] = $rule_quantity_basis;
					$payload['bundle_set_quantity'] = $set_qty;
				}
			}
		}

		$emails_raw = (string) get_post_meta($post_id, '_ToDownload_discount_allowed_customer_emails', true);
		$emails = self::parse_emails_text($emails_raw);
		if (!empty($emails)) {
			$payload['allowed_customer_emails'] = $emails;
		}

		$res = HostedClient::post_json(
			$hosted_base,
			'/api/v1/stores/' . rawurlencode($store_public_id) . '/discounts',
			$payload,
			$api_key,
			$request_id
		);

		if (!empty($res['ok']) && isset($res['data']) && is_array($res['data'])) {
			$d = (array) ($res['data']['discount'] ?? []);
			$public_id = isset($d['publicId']) ? sanitize_text_field((string) $d['publicId']) : '';
			if ($public_id !== '') {
				update_post_meta($post_id, '_ToDownload_hosted_discount_public_id', $public_id);
			}
			delete_post_meta($post_id, '_ToDownload_hosted_discount_sync_error');
			return;
		}

		$msg = isset($res['message']) ? (string) $res['message'] : '';
		if ($msg === '' && isset($res['error']) && is_array($res['error'])) {
			$msg = isset($res['error']['message']) ? (string) $res['error']['message'] : '';
		}
		if ($msg !== '') {
			update_post_meta($post_id, '_ToDownload_hosted_discount_sync_error', sanitize_text_field($msg));
		}
	}

	/**
	 * @return array<int,array{min_quantity:int,percent_off_bps?:int,amount_off_minor?:int}>
	 */
	private static function parse_tier_rules_text(string $raw, string $hosted_type): array {
		$raw = trim((string) $raw);
		if ($raw === '') {
			return [];
		}
		$hosted_type = trim((string) $hosted_type);
		if (!in_array($hosted_type, ['percent', 'amount'], true)) {
			return [];
		}

		$raw = str_replace("\r", "\n", $raw);
		$lines = explode("\n", $raw);
		$by_qty = [];
		foreach ($lines as $line) {
			$line = trim((string) $line);
			if ($line === '') {
				continue;
			}
			// Format: "min_qty: value" (e.g. "2: 10")
			if (!preg_match('/^\s*(\d+)\s*:\s*([0-9]+(?:\.[0-9]+)?)\s*$/', $line, $m)) {
				continue;
			}
			$min_qty = max(0, (int) $m[1]);
			$val = (float) $m[2];
			if ($min_qty <= 0) {
				continue;
			}

			if ($hosted_type === 'percent') {
				$bps = (int) round(max(0.0, min(100.0, $val)) * 100);
				if ($bps <= 0) {
					continue;
				}
				$by_qty[$min_qty] = ['min_quantity' => $min_qty, 'percent_off_bps' => $bps];
			} else {
				$minor = (int) round(max(0.0, $val) * 100);
				if ($minor <= 0) {
					continue;
				}
				$by_qty[$min_qty] = ['min_quantity' => $min_qty, 'amount_off_minor' => $minor];
			}
		}

		if (empty($by_qty)) {
			return [];
		}
		ksort($by_qty);
		return array_values($by_qty);
	}

	public static function apply_discount_code(string $code, array $cart_items, float $subtotal, int $seller_user_id = 0, ?string $buyer_email = null): array {
		$code = strtoupper(trim($code));
		if ($code === '') {
			return ['ok' => true, 'discount' => 0.0, 'code' => ''];
		}

		$seller_user_id = (int) $seller_user_id;
		if ($seller_user_id <= 0) {
			foreach ($cart_items as $it) {
				$download_id = (int) ($it['download_id'] ?? 0);
				if ($download_id > 0) {
					$seller_user_id = (int) get_post_field('post_author', $download_id);
					break;
				}
			}
		}

		$discount_post_id = self::find_discount_post_id($code, $seller_user_id);
		if (!$discount_post_id) {
			return ['ok' => false, 'message' => __('Invalid discount code.', '2download-connector')];
		}

		$expires = (string) get_post_meta($discount_post_id, '_ToDownload_discount_expires', true);
		if ($expires !== '') {
			$ts = strtotime($expires . ' 23:59:59');
			if ($ts && time() > $ts) {
				return ['ok' => false, 'message' => __('This discount code has expired.', '2download-connector')];
			}
		}

		$usage_limit = (int) get_post_meta($discount_post_id, '_ToDownload_discount_usage_limit', true);
		$usage_count = (int) get_post_meta($discount_post_id, '_ToDownload_discount_usage_count', true);
		if ($usage_limit > 0 && $usage_count >= $usage_limit) {
			return ['ok' => false, 'message' => __('This discount code has reached its usage limit.', '2download-connector')];
		}

		$buyer_email = sanitize_email((string) $buyer_email);
		$usage_limit_per_customer = (int) get_post_meta($discount_post_id, '_ToDownload_discount_usage_limit_per_customer', true);
		$returning_only = (string) get_post_meta($discount_post_id, '_ToDownload_discount_returning_customers_only', true) === '1';
		$first_time_only = (string) get_post_meta($discount_post_id, '_ToDownload_discount_first_time_customers_only', true) === '1';

		if (($usage_limit_per_customer > 0 || $returning_only || $first_time_only) && ($buyer_email === '' || !is_email($buyer_email))) {
			return ['ok' => false, 'message' => __('Please enter a valid email to use this discount code.', '2download-connector')];
		}

		if ($buyer_email !== '' && is_email($buyer_email)) {
			$prior_complete_for_seller = 0;
			$prior_complete_with_code = 0;
			$orders = Orders::find_orders_by_email($buyer_email);
			foreach ($orders as $o) {
				if (!is_array($o)) {
					continue;
				}
				if ((string) ($o['status'] ?? '') !== 'complete') {
					continue;
				}
				if ((int) ($o['seller_user_id'] ?? 0) !== (int) $seller_user_id) {
					continue;
				}
				$prior_complete_for_seller++;

				$notes = (string) ($o['notes'] ?? '');
				if ($notes !== '' && strpos($notes, 'ToDownload_discount_code: ' . $code) !== false) {
					$prior_complete_with_code++;
				}
			}

			if ($returning_only && $prior_complete_for_seller <= 0) {
				return ['ok' => false, 'message' => __('This discount code is only for returning customers.', '2download-connector')];
			}
			if ($first_time_only && $prior_complete_for_seller > 0) {
				return ['ok' => false, 'message' => __('This discount code is only for first-time customers.', '2download-connector')];
			}
			if ($usage_limit_per_customer > 0 && $prior_complete_with_code >= $usage_limit_per_customer) {
				return ['ok' => false, 'message' => __('This discount code has reached its per-customer limit.', '2download-connector')];
			}
		}

		$product_ids_raw = (string) get_post_meta($discount_post_id, '_ToDownload_discount_product_ids', true);
		$allowed_ids = self::parse_ids_csv($product_ids_raw);
		if (!empty($allowed_ids)) {
			$cart_ids = array_map(fn($it) => (int) ($it['download_id'] ?? 0), $cart_items);
			$matches = array_intersect($allowed_ids, $cart_ids);
			if (empty($matches)) {
				return ['ok' => false, 'message' => __('This discount code does not apply to items in your cart.', '2download-connector')];
			}
		}

		$type = (string) get_post_meta($discount_post_id, '_ToDownload_discount_type', true);
		$amount = (float) get_post_meta($discount_post_id, '_ToDownload_discount_amount', true);
		$min_quantity = (int) get_post_meta($discount_post_id, '_ToDownload_discount_min_quantity', true);
		$max_discount = (string) get_post_meta($discount_post_id, '_ToDownload_discount_max_discount', true);
		$cart_rule = (string) get_post_meta($discount_post_id, '_ToDownload_discount_cart_rule', true);
		$rule_quantity_basis = (string) get_post_meta($discount_post_id, '_ToDownload_discount_rule_quantity_basis', true);
		$tier_rules_text = (string) get_post_meta($discount_post_id, '_ToDownload_discount_tier_rules_text', true);
		$cheapest_item_quantity = (int) get_post_meta($discount_post_id, '_ToDownload_discount_cheapest_item_quantity', true);
		$cheapest_item_percent_off = (float) get_post_meta($discount_post_id, '_ToDownload_discount_cheapest_item_percent_off', true);
		$bundle_set_quantity = (int) get_post_meta($discount_post_id, '_ToDownload_discount_bundle_set_quantity', true);
		$excluded_ids_raw = (string) get_post_meta($discount_post_id, '_ToDownload_discount_excluded_product_ids', true);
		$excluded_ids = self::parse_ids_csv($excluded_ids_raw);

		$total_unit_amounts_minor = [];
		$eligible_unit_amounts_minor = [];
		foreach ($cart_items as $it) {
			$download_id = (int) ($it['download_id'] ?? 0);
			if ($download_id <= 0) {
				continue;
			}
			$price = isset($it['price']) ? (float) $it['price'] : 0.0;
			$minor = (int) round(max(0.0, $price) * 100);
			if ($minor <= 0) {
				continue;
			}
			$total_unit_amounts_minor[] = $minor;
			if (!empty($excluded_ids) && in_array($download_id, $excluded_ids, true)) {
				continue;
			}
			if (!empty($allowed_ids) && !in_array($download_id, $allowed_ids, true)) {
				continue;
			}
			$eligible_unit_amounts_minor[] = $minor;
		}
		$eligible_subtotal_minor = array_sum($eligible_unit_amounts_minor);
		$total_count = count($total_unit_amounts_minor);
		$eligible_count = count($eligible_unit_amounts_minor);
		$basis = in_array($rule_quantity_basis, ['eligible', 'total'], true) ? $rule_quantity_basis : 'eligible';
		$basis_count = $basis === 'total' ? $total_count : $eligible_count;

		if ($min_quantity > 0 && $eligible_count < $min_quantity) {
			return ['ok' => false, 'message' => __('Your cart does not meet the minimum quantity for this discount code.', '2download-connector')];
		}

		$discount = 0.0;
		$cart_rule = in_array($cart_rule, ['tiered', 'cheapest', 'bundle'], true) ? $cart_rule : '';
		if ($type === 'bogo') {
			$buy_qty = (int) get_post_meta($discount_post_id, '_ToDownload_discount_bogo_buy_quantity', true);
			$get_qty = (int) get_post_meta($discount_post_id, '_ToDownload_discount_bogo_get_quantity', true);
			$pct = (float) get_post_meta($discount_post_id, '_ToDownload_discount_bogo_get_percent_off', true);
			$buy_qty = max(1, $buy_qty);
			$get_qty = max(1, $get_qty);
			$set_size = $buy_qty + $get_qty;
			$sets = (int) floor(count($eligible_unit_amounts_minor) / $set_size);
			$discount_units = $sets * $get_qty;
			if ($discount_units <= 0) {
				return ['ok' => false, 'message' => __('This discount code does not apply to items in your cart.', '2download-connector')];
			}
			$pct = max(0.0, min(100.0, $pct > 0 ? $pct : 100.0));
			$bps = (int) round($pct * 100);
			sort($eligible_unit_amounts_minor);
			$chosen = array_slice($eligible_unit_amounts_minor, 0, $discount_units);
			$discount_minor = 0;
			foreach ($chosen as $unit_minor) {
				$discount_minor += (int) floor(((int) $unit_minor * $bps) / 10000);
			}
			$discount = min($subtotal, max(0.0, ((float) $discount_minor) / 100.0));
		} else if ($cart_rule === 'tiered' && ($type === 'percent' || $type === 'flat')) {
			$hosted_type = $type === 'flat' ? 'amount' : 'percent';
			$tiers = self::parse_tier_rules_text($tier_rules_text, $hosted_type);
			if (empty($tiers)) {
				return ['ok' => false, 'message' => __('This discount code does not apply to items in your cart.', '2download-connector')];
			}
			$chosen = null;
			foreach ($tiers as $tr) {
				$minq = (int) ($tr['min_quantity'] ?? 0);
				if ($minq > 0 && $minq <= $basis_count) {
					$chosen = $tr;
				}
			}
			if (!$chosen) {
				return ['ok' => false, 'message' => __('This discount code does not apply to items in your cart.', '2download-connector')];
			}
			if ($hosted_type === 'percent') {
				$bps = (int) ($chosen['percent_off_bps'] ?? 0);
				$discount_minor = (int) floor(((int) $eligible_subtotal_minor * $bps) / 10000);
				$discount = min($subtotal, max(0.0, ((float) $discount_minor) / 100.0));
			} else {
				$minor = (int) ($chosen['amount_off_minor'] ?? 0);
				$discount = min($subtotal, max(0.0, min(((float) $eligible_subtotal_minor) / 100.0, ((float) $minor) / 100.0)));
			}
		} else if ($cart_rule === 'cheapest' && $type === 'percent') {
			$qty = max(0, (int) $cheapest_item_quantity);
			$bps = (int) round(max(0.0, min(100.0, $cheapest_item_percent_off)) * 100);
			if ($qty <= 0 || $bps <= 0 || $eligible_count < $qty) {
				return ['ok' => false, 'message' => __('This discount code does not apply to items in your cart.', '2download-connector')];
			}
			sort($eligible_unit_amounts_minor);
			$chosen_units = array_slice($eligible_unit_amounts_minor, 0, $qty);
			$discount_minor = 0;
			foreach ($chosen_units as $unit_minor) {
				$discount_minor += (int) floor(((int) $unit_minor * $bps) / 10000);
			}
			$discount = min($subtotal, max(0.0, ((float) $discount_minor) / 100.0));
		} else if ($cart_rule === 'bundle' && $type === 'fixed_price') {
			$set_qty = max(0, (int) $bundle_set_quantity);
			$sets = $set_qty > 0 ? (int) floor($basis_count / $set_qty) : 0;
			if ($set_qty <= 0 || $sets <= 0 || $eligible_count < ($sets * $set_qty)) {
				return ['ok' => false, 'message' => __('This discount code does not apply to items in your cart.', '2download-connector')];
			}
			$fixed_price_minor = (int) round(max(0.0, $amount) * 100);
			rsort($eligible_unit_amounts_minor);
			$take = $sets * $set_qty;
			$bundle_units = array_slice($eligible_unit_amounts_minor, 0, $take);
			$bundle_subtotal_minor = array_sum($bundle_units);
			$discount_minor = max(0, $bundle_subtotal_minor - ($sets * $fixed_price_minor));
			$discount = min($subtotal, max(0.0, ((float) $discount_minor) / 100.0));
		} else if ($type === 'flat') {
			$discount = min($subtotal, max(0.0, min(((float) $eligible_subtotal_minor) / 100.0, $amount)));
		} else if ($type === 'fixed_price') {
			$fixed_price_minor = (int) round(max(0.0, $amount) * 100);
			$discount_minor = max(0, $eligible_subtotal_minor - $fixed_price_minor);
			$discount = min($subtotal, max(0.0, ((float) $discount_minor) / 100.0));
		} else {
			$percent = max(0.0, min(100.0, $amount));
			$discount = (((float) $eligible_subtotal_minor) / 100.0) * ($percent / 100.0);
			$discount = min($subtotal, max(0.0, $discount));
		}

		if ($max_discount !== '') {
			$cap = (float) $max_discount;
			if ($cap > 0) {
				$discount = min($discount, $cap);
			}
		}

		return [
			'ok' => true,
			'code' => $code,
			'discount' => (float) round($discount, 2),
			'discount_post_id' => $discount_post_id,
		];
	}

	private static function parse_ids_csv(string $csv): array {
		$csv = trim($csv);
		if ($csv === '') {
			return [];
		}
		$parts = array_filter(array_map('trim', explode(',', $csv)));
		$out = [];
		foreach ($parts as $p) {
			$id = (int) $p;
			if ($id > 0) {
				$out[] = $id;
			}
		}
		return array_values(array_unique($out));
	}

	private static function find_discount_post_id(string $code, int $seller_user_id = 0): int {
		$args = [
			'post_type' => self::POST_TYPE,
			'post_status' => 'publish',
			'numberposts' => 1,
			'fields' => 'ids',
			'no_found_rows' => true,
			// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query -- Required lookup by discount code.
			'meta_query' => [
				[
					'key' => '_ToDownload_discount_code',
					'value' => $code,
					'compare' => '=',
				],
			],
		];
		$seller_user_id = (int) $seller_user_id;
		if ($seller_user_id > 0) {
			$args['author'] = $seller_user_id;
		}

		$posts = get_posts($args);

		return !empty($posts) ? (int) $posts[0] : 0;
	}

	public static function on_order_complete(int $order_id): void {
		$order = Orders::get_order($order_id);
		if (!$order) {
			return;
		}
		$notes = (string) ($order['notes'] ?? '');
		if ($notes === '') {
			return;
		}

		// Look for marker like: "ToDownload_discount_code: SAVE10"
		if (!preg_match('/ToDownload_discount_code:\s*([A-Z0-9_-]+)/', $notes, $m)) {
			return;
		}
		$code = strtoupper(trim((string) $m[1]));
		if ($code === '') {
			return;
		}

		$seller_user_id = (int) ($order['seller_user_id'] ?? 0);
		$discount_post_id = self::find_discount_post_id($code, $seller_user_id);
		if (!$discount_post_id) {
			return;
		}

		$usage_count = (int) get_post_meta($discount_post_id, '_ToDownload_discount_usage_count', true);
		update_post_meta($discount_post_id, '_ToDownload_discount_usage_count', $usage_count + 1);
	}
}