Add custom walker for section hierarchy display and sync products from section term meta

Author: ajaydsouza

includes/admin/class-product-section-selector.php

@@ -43,6 +43,8 @@ class Product_Section_Selector {
 	 * Constructor.
 	 */
 	public function __construct() {
+		Hook_Registry::add_filter( 'wp_terms_checklist_args', array( $this, 'use_hierarchical_section_walker' ), 10, 2 );
+
 		if ( 0 === (int) wzkb_get_option( 'multi_product', 0 ) ) {
 			return;
 		}
@@ -361,6 +363,7 @@ public function sync_sections_after_rest_save( \WP_Post $post, \WP_REST_Request
 			$this->assign_section_terms( $post->ID, $request['meta']['_wzkb_section_ids'] );
 		}
 
+		$this->sync_products_from_sections( $post->ID );
 		$this->sync_product_meta( $post->ID );
 		$this->sync_section_product_meta( $post->ID );
 	}
@@ -382,18 +385,33 @@ public function maybe_sync_sections_during_save( $post_id, $post ) {
 
 		$this->is_syncing = true;
 
-		$section_ids = get_post_meta( $post_id, '_wzkb_section_ids', true );
+		// Quick Edit saves taxonomy terms directly without updating post meta.
+		// Read back what WordPress just saved so meta stays in sync, then let
+		// sync_products_from_sections derive product assignments from sections.
+		// phpcs:ignore WordPress.Security.NonceVerification.Missing -- action detection only, no data used.
+		$is_quick_edit = isset( $_POST['action'] ) && 'inline-save' === $_POST['action']; // phpcs:ignore WordPress.Security.NonceVerification.Missing
 
-		if ( empty( $section_ids ) ) {
+		if ( $is_quick_edit ) {
 			$current_terms = get_the_terms( $post_id, 'wzkb_category' );
-			if ( ! empty( $current_terms ) && ! is_wp_error( $current_terms ) ) {
-				$section_ids = array_map( 'absint', wp_list_pluck( $current_terms, 'term_id' ) );
-				update_post_meta( $post_id, '_wzkb_section_ids', $section_ids );
+			$section_ids   = ( ! empty( $current_terms ) && ! is_wp_error( $current_terms ) )
+				? array_map( 'absint', wp_list_pluck( $current_terms, 'term_id' ) )
+				: array();
+			update_post_meta( $post_id, '_wzkb_section_ids', $section_ids );
+		} else {
+			$section_ids = get_post_meta( $post_id, '_wzkb_section_ids', true );
+
+			if ( empty( $section_ids ) ) {
+				$current_terms = get_the_terms( $post_id, 'wzkb_category' );
+				if ( ! empty( $current_terms ) && ! is_wp_error( $current_terms ) ) {
+					$section_ids = array_map( 'absint', wp_list_pluck( $current_terms, 'term_id' ) );
+					update_post_meta( $post_id, '_wzkb_section_ids', $section_ids );
+				}
 			}
 		}
 
 		try {
 			$this->assign_section_terms( $post_id, $section_ids );
+			$this->sync_products_from_sections( $post_id );
 			$this->sync_product_meta( $post_id );
 			$this->sync_section_product_meta( $post_id );
 		} finally {
@@ -473,6 +491,47 @@ private function sync_product_meta( $post_id ) {
 		update_post_meta( $post_id, '_wzkb_product_ids', array_values( $product_ids ) );
 	}
 
+	/**
+	 * Merge product assignments derived from assigned sections.
+	 *
+	 * Each section can carry a `product_id` term meta. Any product referenced
+	 * this way is added to the post's wzkb_product taxonomy so the article is
+	 * always discoverable from its product. Existing product assignments are
+	 * preserved — this only ever adds, never removes.
+	 *
+	 * @param int $post_id Post ID.
+	 */
+	private function sync_products_from_sections( int $post_id ): void {
+		$section_terms = get_the_terms( $post_id, 'wzkb_category' );
+		if ( empty( $section_terms ) || is_wp_error( $section_terms ) ) {
+			return;
+		}
+
+		$derived_ids = array();
+		foreach ( $section_terms as $section ) {
+			$product_id = (int) get_term_meta( $section->term_id, 'product_id', true );
+			if ( $product_id > 0 ) {
+				$derived_ids[] = $product_id;
+			}
+		}
+
+		if ( empty( $derived_ids ) ) {
+			return;
+		}
+
+		$current_terms = get_the_terms( $post_id, 'wzkb_product' );
+		$current_ids   = ( ! empty( $current_terms ) && ! is_wp_error( $current_terms ) )
+			? array_map( 'absint', wp_list_pluck( $current_terms, 'term_id' ) )
+			: array();
+
+		$to_add = array_diff( $derived_ids, $current_ids );
+		if ( empty( $to_add ) ) {
+			return;
+		}
+
+		wp_set_post_terms( $post_id, array_values( array_unique( array_merge( $current_ids, $derived_ids ) ) ), 'wzkb_product', false );
+	}
+
 	/**
 	 * Backfill product_id term meta on sections that have none.
 	 *
@@ -500,8 +559,7 @@ private function sync_section_product_meta( int $post_id ): void {
 		$product_id = (int) $product_terms[0]->term_id;
 
 		foreach ( $section_terms as $section ) {
-			$existing_product_id = get_term_meta( $section->term_id, 'product_id', true );
-			if ( '' === $existing_product_id ) {
+			if ( 0 === (int) get_term_meta( $section->term_id, 'product_id', true ) ) {
 				update_term_meta( $section->term_id, 'product_id', $product_id );
 			}
 		}
@@ -622,4 +680,21 @@ private function get_ui_strings(): array {
 			'productOverflow'   => esc_html__( 'Showing first %1$s products out of %2$s. Refine your search.', 'knowledgebase' ),
 		);
 	}
+
+	/**
+	 * Inject Walker_Section_Checklist for the wzkb_category checklist (Quick Edit and post editor).
+	 *
+	 * @param array $args    wp_terms_checklist() arguments.
+	 * @param int   $post_id Post ID (unused).
+	 * @return array
+	 */
+	public function use_hierarchical_section_walker( array $args, $post_id ): array {
+		if ( ! isset( $args['taxonomy'] ) || 'wzkb_category' !== $args['taxonomy'] ) {
+			return $args;
+		}
+
+		$args['walker'] = new Walker_Section_Checklist();
+
+		return $args;
+	}
 }

includes/admin/class-walker-section-checklist.php

@@ -0,0 +1,60 @@
+<?php
+/**
+ * Custom walker for wzkb_category checkbox lists with hierarchical labels.
+ *
+ * @since 3.0.0
+ *
+ * @package WebberZone\\Knowledge_Base\\Admin
+ */
+
+namespace WebberZone\Knowledge_Base\Admin;
+
+// If this file is called directly, abort.
+if ( ! defined( 'WPINC' ) ) {
+	die;
+}
+
+/**
+ * Custom walker for wzkb_category checkbox lists (Quick Edit, term metaboxes).
+ *
+ * Mirrors the label format used by Walker_Category_Dropdown: shows the full
+ * product > section hierarchy path via wzkb_get_term_hierarchy_path() so
+ * child terms are unambiguously identified without relying on visual context.
+ *
+ * @since 3.0.0
+ */
+class Walker_Section_Checklist extends \Walker_Category_Checklist {
+
+	/**
+	 * Start element output.
+	 *
+	 * @param string $output            Passed by reference.
+	 * @param object $data_object       Term object.
+	 * @param int    $depth             Depth of term in tree.
+	 * @param array  $args              Walker args.
+	 * @param int    $current_object_id Current post/object ID.
+	 */
+	public function start_el( &$output, $data_object, $depth = 0, $args = array(), $current_object_id = 0 ) {
+		$term     = $data_object;
+		$taxonomy = ! empty( $args['taxonomy'] ) ? $args['taxonomy'] : 'category';
+		$name     = 'tax_input[' . $taxonomy . ']';
+
+		$args['popular_cats']  = ! empty( $args['popular_cats'] ) ? array_map( 'intval', $args['popular_cats'] ) : array();
+		$class                 = in_array( $term->term_id, $args['popular_cats'], true ) ? ' class="popular-category"' : '';
+		$args['selected_cats'] = ! empty( $args['selected_cats'] ) ? array_map( 'intval', $args['selected_cats'] ) : array();
+
+		$is_selected   = in_array( $term->term_id, $args['selected_cats'], true );
+		$li_attributes = $is_selected ? ' aria-checked="true"' : '';
+		$checked       = checked( $is_selected, true, false );
+		$disabled      = ! empty( $args['disabled'] ) ? ' disabled="disabled"' : '';
+		$checkbox_id   = 'in-' . $taxonomy . '-' . $term->term_id;
+		$pad           = str_repeat( '&nbsp;', $depth * 3 );
+		$label         = esc_html( wzkb_get_term_hierarchy_path( $term, true, ' > ' ) );
+
+		$output .= "\n<li id='{$taxonomy}-{$term->term_id}'{$class}{$li_attributes}>" .
+			"<label class='selectit' for='{$checkbox_id}'>" .
+			"<input value='{$term->term_id}' type='checkbox' name='{$name}[]' id='{$checkbox_id}'{$disabled}{$checked} /> " .
+			$pad . $label .
+			'</label>';
+	}
+}

includes/admin/css/editor-sections-panel-rtl.css

@@ -54,10 +54,6 @@
 	margin: 3px 0;
 }
 
-.wzkb-editor-sections__node--child {
-	margin-top: 6px;
-}
-
 .wzkb-editor-sections__empty {
 	font-style: italic;
 	margin: 0;

includes/admin/css/editor-sections-panel-rtl.min.css

@@ -54,10 +54,6 @@
 	margin: 3px 0;
 }
 
-.wzkb-editor-sections__node--child {
-	margin-top: 6px;
-}
-
 .wzkb-editor-sections__empty {
 	font-style: italic;
 	margin: 0;

includes/admin/css/editor-sections-panel.css

@@ -293,9 +293,9 @@
 	};
 
 	const appendTree = (container, nodes, level) => {
+		const prefix = level > 0 ? '\u00a0'.repeat( ( level - 1 ) * 3 ) + '\u21b3\u00a0' : '';
 		nodes.forEach((node) => {
 			const row = createElement('div', 'wzkb-classic-sections__node');
-			row.style.marginLeft = `${level * 16}px`;
 
 			const checkbox = createElement('input');
 			checkbox.type = 'checkbox';
@@ -310,7 +310,7 @@
 				updateHiddenInputs();
 			});
 
-			const label = createElement('span', 'wzkb-classic-sections__node-label', node.name);
+			const label = createElement('span', 'wzkb-classic-sections__node-label', prefix + node.name);
 			row.appendChild(checkbox);
 			row.appendChild(label);
 			container.appendChild(row);