// --------- Help Center Brands Menu (functions.php) ---------
// Add this to your Astra child theme's functions.php (append at end)

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

/**
 * Shortcode: [help_brands_menu]
 * Outputs a nested UL of top-level 'model' terms (brands) and their child terms (models).
 * Adds "Other" when posts are assigned directly to the brand (exclude children).
 */

add_shortcode( 'help_brands_menu', 'hw_help_brands_menu_shortcode' );
function hw_help_brands_menu_shortcode( $atts ) {
	// Basic environment checks
	if ( ! taxonomy_exists( 'model' ) || ! post_type_exists( 'help' ) ) {
		return '<div class="help-brands-error">Help menu: required CPT <code>help</code> or taxonomy <code>model</code> not found.</div>';
	}

	// Get top-level terms = brands
	$brands = get_terms( array(
		'taxonomy'   => 'model',
		'hide_empty' => false,
		'parent'     => 0,
		'orderby'    => 'name',
	) );

	if ( is_wp_error( $brands ) || empty( $brands ) ) {
		return '<div class="help-brands-empty">No brands found.</div>';
	}

	// Determine current queried term (if any) to mark active and expand branch
	$current_term_id = 0;
	if ( is_tax( 'model' ) ) {
		$queried = get_queried_object();
		if ( isset( $queried->term_id ) ) {
			$current_term_id = (int) $queried->term_id;
		}
	}

	$menu_id = 'help-brands-menu-' . uniqid();
	$html = '<nav id="' . esc_attr( $menu_id ) . '" class="help-brands-menu" aria-label="Help Brands Menu">';
	$html .= '<ul class="help-brands-root">';

	foreach ( $brands as $brand ) {
		// Brand link and classes
		$brand_link = get_term_link( $brand );
		if ( is_wp_error( $brand_link ) ) {
			continue;
		}

		// Get child models for this brand
		$children = get_terms( array(
			'taxonomy'   => 'model',
			'hide_empty' => false,
			'parent'     => $brand->term_id,
			'orderby'    => 'name',
		) );

		// Determine if current term is this brand or a child (to expand)
		$brand_is_active = ( $current_term_id === (int) $brand->term_id );
		$child_contains_current = false;
		if ( ! empty( $children ) && $current_term_id ) {
			foreach ( $children as $c ) {
				if ( (int) $c->term_id === $current_term_id ) {
					$child_contains_current = true;
					break;
				}
			}
		}

		// Brand <li> open
		$expanded_attr = ( $brand_is_active || $child_contains_current ) ? 'true' : 'false';
		$expanded_class = ( $brand_is_active || $child_contains_current ) ? ' expanded' : '';
		$html .= '<li class="brand-item' . esc_attr( $expanded_class ) . '">';

		// Brand anchor (we'll toggle on click via JS — set a data-target)
		$html .= '<a href="' . esc_url( $brand_link ) . '" class="brand-link" aria-expanded="' . esc_attr( $expanded_attr ) . '" data-term-id="' . esc_attr( $brand->term_id ) . '">';
		$html .= esc_html( $brand->name );
		// optional: counts (comment out if you prefer)
		$html .= ' <span class="count">(' . intval( $brand->count ) . ')</span>';
		$html .= '</a>';

		// Children list (models)
		$html .= '<ul class="children" data-parent-id="' . esc_attr( $brand->term_id ) . '"';
		// collapse by default unless expanded
		$html .= ( $expanded_attr === 'true' ) ? ' aria-hidden="false">' : ' aria-hidden="true">';
		if ( ! empty( $children ) ) {
			foreach ( $children as $child ) {
				$child_link = get_term_link( $child );
				if ( is_wp_error( $child_link ) ) {
					continue;
				}
				$child_class = ( $current_term_id === (int) $child->term_id ) ? ' class="current-term"' : '';
				$html .= '<li class="model-item"><a href="' . esc_url( $child_link ) . '"' . $child_class . '>' . esc_html( $child->name ) . ' <span class="count">(' . intval( $child->count ) . ')</span></a></li>';
			}
		}

		// "Other" logic: show only when there are posts assigned directly to brand (exclude children)
		$other_count = hw_get_brand_direct_post_count( $brand->term_id );
		if ( $other_count > 0 ) {
			// build brand archive link with ?brand_other=1
			$brand_other_link = add_query_arg( 'brand_other', 1, $brand_link );
			$html .= '<li class="model-item other-item"><a href="' . esc_url( $brand_other_link ) . '">' . esc_html__( 'Other', 'your-textdomain' ) . ' <span class="count">(' . intval( $other_count ) . ')</span></a></li>';
		}

		$html .= '</ul>'; // .children
		$html .= '</li>'; // .brand-item
	}

	$html .= '</ul>';
	$html .= '</nav>';

	return $html;
}

/**
 * Helper: return number of posts of post_type 'help' assigned DIRECTLY to a term (exclude children)
 */
function hw_get_brand_direct_post_count( $brand_term_id ) {
	// Quick check
	if ( empty( $brand_term_id ) ) {
		return 0;
	}

	$q = new WP_Query( array(
		'post_type'      => 'help',
		'tax_query'      => array(
			array(
				'taxonomy'         => 'model',
				'terms'            => intval( $brand_term_id ),
				'field'            => 'term_id',
				'include_children' => false,
			),
		),
		'posts_per_page' => 1, // we only need to know if any exist, but to show count we need actual count
		'no_found_rows'  => true,
		'fields'         => 'ids',
	) );

	// Because we used posts_per_page=1 & no_found_rows=true, we don't have total. For accurate count, use get_objects_in_term fallback:
	if ( $q->have_posts() ) {
		// We need accurate count for the UI; use get_objects_in_term which returns object IDs assigned exactly to the term (does not include children)
		$objects = get_objects_in_term( intval( $brand_term_id ), 'model' );
		if ( is_array( $objects ) ) {
			// filter by post_type 'help'
			$count = 0;
			foreach ( $objects as $post_id ) {
				$post = get_post( $post_id );
				if ( $post && $post->post_type === 'help' && $post->post_status === 'publish' ) {
					$count++;
				}
			}
			return $count;
		}
		return 0;
	}

	// No posts found quickly
	return 0;
}

/**
 * Add query var 'brand_other' so WP recognizes it.
 */
add_filter( 'query_vars', 'hw_add_brand_other_query_var' );
function hw_add_brand_other_query_var( $vars ) {
	$vars[] = 'brand_other';
	return $vars;
}

/**
 * pre_get_posts handler: if brand_other=1 on a model archive, restrict main query to posts directly assigned to that brand term.
 */
add_action( 'pre_get_posts', 'hw_filter_brand_other_pre_get_posts' );
function hw_filter_brand_other_pre_get_posts( $query ) {
	// Only affect front end main query
	if ( is_admin() || ! $query->is_main_query() ) {
		return;
	}

	// Check if on model taxonomy archive and brand_other flag is present
	if ( is_tax( 'model' ) && get_query_var( 'brand_other', 0 ) ) {
		$term = get_queried_object();
		if ( ! $term || empty( $term->term_id ) ) {
			return;
		}

		// Force post_type to 'help' (only for this archive)
		$query->set( 'post_type', 'help' );

		// Build tax_query: only posts directly in the brand term (exclude children)
		$tax_query = array(
			array(
				'taxonomy'         => 'model',
				'terms'            => intval( $term->term_id ),
				'field'            => 'term_id',
				'include_children' => false,
			),
		);
		$query->set( 'tax_query', $tax_query );

		// Optional: ensure posts are published
		$query->set( 'post_status', 'publish' );
	}
}
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