schema-article.php

require_once get_template_directory() . '/inc/helpers/schema-article.php';

<?php
/**
 * RX Theme - Advanced Article Schema JSON-LD
 *
 * File: inc/helpers/schema-article.php
 *
 * Features:
 * - Article / BlogPosting / MedicalWebPage / MedicalScholarlyArticle support
 * - Author schema
 * - Publisher schema
 * - Organization schema
 * - WebSite schema
 * - WebPage schema
 * - BreadcrumbList schema
 * - ImageObject schema
 * - Person schema
 * - Speakable schema
 * - FAQPage schema from post meta
 * - HowTo schema from post meta
 * - MedicalEntity-ready schema fields
 * - Last modified date support
 * - Reading time support
 * - Word count support
 * - Keywords support
 * - SameAs social links support
 * - Safe sanitization and escaping
 *
 * @package RX_Theme
 */

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

if ( ! function_exists( 'rx_schema_clean_text' ) ) {
	/**
	 * Clean text for schema output.
	 *
	 * @param string $text Raw text.
	 * @return string
	 */
	function rx_schema_clean_text( $text ) {
		$text = wp_strip_all_tags( $text );
		$text = html_entity_decode( $text, ENT_QUOTES, get_bloginfo( 'charset' ) );
		$text = preg_replace( '/\s+/', ' ', $text );
		return trim( $text );
	}
}

if ( ! function_exists( 'rx_schema_get_excerpt' ) ) {
	/**
	 * Get SEO-safe article excerpt.
	 *
	 * @param int $post_id Post ID.
	 * @return string
	 */
	function rx_schema_get_excerpt( $post_id ) {
		$excerpt = get_the_excerpt( $post_id );

		if ( empty( $excerpt ) ) {
			$post    = get_post( $post_id );
			$content = isset( $post->post_content ) ? $post->post_content : '';
			$excerpt = wp_trim_words( wp_strip_all_tags( strip_shortcodes( $content ) ), 35, '' );
		}

		return rx_schema_clean_text( $excerpt );
	}
}

if ( ! function_exists( 'rx_schema_get_word_count' ) ) {
	/**
	 * Get article word count.
	 *
	 * @param int $post_id Post ID.
	 * @return int
	 */
	function rx_schema_get_word_count( $post_id ) {
		$post = get_post( $post_id );

		if ( ! $post || empty( $post->post_content ) ) {
			return 0;
		}

		$content = wp_strip_all_tags( strip_shortcodes( $post->post_content ) );
		$words   = preg_split( '/\s+/', trim( $content ) );

		return is_array( $words ) ? count( array_filter( $words ) ) : 0;
	}
}

if ( ! function_exists( 'rx_schema_get_reading_time' ) ) {
	/**
	 * Estimate reading time.
	 *
	 * @param int $post_id Post ID.
	 * @return string
	 */
	function rx_schema_get_reading_time( $post_id ) {
		$word_count = rx_schema_get_word_count( $post_id );
		$minutes    = max( 1, ceil( $word_count / 200 ) );

		return 'PT' . absint( $minutes ) . 'M';
	}
}

if ( ! function_exists( 'rx_schema_get_logo_url' ) ) {
	/**
	 * Get website logo URL.
	 *
	 * @return string
	 */
	function rx_schema_get_logo_url() {
		$custom_logo_id = get_theme_mod( 'custom_logo' );

		if ( $custom_logo_id ) {
			$logo = wp_get_attachment_image_url( $custom_logo_id, 'full' );

			if ( $logo ) {
				return esc_url_raw( $logo );
			}
		}

		$site_icon = get_site_icon_url( 512 );

		if ( $site_icon ) {
			return esc_url_raw( $site_icon );
		}

		return esc_url_raw( get_template_directory_uri() . '/assets/images/logo.png' );
	}
}

if ( ! function_exists( 'rx_schema_get_post_image' ) ) {
	/**
	 * Get post image schema.
	 *
	 * @param int $post_id Post ID.
	 * @return array|null
	 */
	function rx_schema_get_post_image( $post_id ) {
		$image_id = get_post_thumbnail_id( $post_id );

		if ( ! $image_id ) {
			return null;
		}

		$image_url = wp_get_attachment_image_url( $image_id, 'full' );

		if ( ! $image_url ) {
			return null;
		}

		$metadata = wp_get_attachment_metadata( $image_id );

		$image_schema = array(
			'@type' => 'ImageObject',
			'@id'   => esc_url_raw( $image_url ) . '#primaryimage',
			'url'   => esc_url_raw( $image_url ),
		);

		if ( ! empty( $metadata['width'] ) ) {
			$image_schema['width'] = absint( $metadata['width'] );
		}

		if ( ! empty( $metadata['height'] ) ) {
			$image_schema['height'] = absint( $metadata['height'] );
		}

		$alt = get_post_meta( $image_id, '_wp_attachment_image_alt', true );

		if ( ! empty( $alt ) ) {
			$image_schema['caption'] = rx_schema_clean_text( $alt );
		}

		return $image_schema;
	}
}

if ( ! function_exists( 'rx_schema_get_author_schema' ) ) {
	/**
	 * Get author schema.
	 *
	 * @param int $author_id Author ID.
	 * @return array
	 */
	function rx_schema_get_author_schema( $author_id ) {
		$author_url         = get_author_posts_url( $author_id );
		$author_name        = get_the_author_meta( 'display_name', $author_id );
		$author_description = get_the_author_meta( 'description', $author_id );

		$same_as = array();

		$social_fields = array(
			'facebook',
			'twitter',
			'x',
			'linkedin',
			'youtube',
			'instagram',
			'pinterest',
			'github',
			'website',
		);

		foreach ( $social_fields as $field ) {
			$value = get_the_author_meta( $field, $author_id );

			if ( ! empty( $value ) && filter_var( $value, FILTER_VALIDATE_URL ) ) {
				$same_as[] = esc_url_raw( $value );
			}
		}

		$schema = array(
			'@type' => 'Person',
			'@id'   => esc_url_raw( $author_url ) . '#author',
			'name'  => rx_schema_clean_text( $author_name ),
			'url'   => esc_url_raw( $author_url ),
		);

		if ( ! empty( $author_description ) ) {
			$schema['description'] = rx_schema_clean_text( $author_description );
		}

		if ( ! empty( $same_as ) ) {
			$schema['sameAs'] = array_values( array_unique( $same_as ) );
		}

		return $schema;
	}
}

if ( ! function_exists( 'rx_schema_get_organization_schema' ) ) {
	/**
	 * Get organization schema.
	 *
	 * @return array
	 */
	function rx_schema_get_organization_schema() {
		$home_url  = home_url( '/' );
		$logo_url  = rx_schema_get_logo_url();
		$site_name = get_bloginfo( 'name' );

		$same_as = array();

		/**
		 * Add your official social links here.
		 */
		$theme_social_links = array(
			get_theme_mod( 'rx_facebook_url' ),
			get_theme_mod( 'rx_twitter_url' ),
			get_theme_mod( 'rx_linkedin_url' ),
			get_theme_mod( 'rx_youtube_url' ),
			get_theme_mod( 'rx_instagram_url' ),
			get_theme_mod( 'rx_pinterest_url' ),
		);

		foreach ( $theme_social_links as $link ) {
			if ( ! empty( $link ) && filter_var( $link, FILTER_VALIDATE_URL ) ) {
				$same_as[] = esc_url_raw( $link );
			}
		}

		$schema = array(
			'@type' => 'Organization',
			'@id'   => esc_url_raw( $home_url ) . '#organization',
			'name'  => rx_schema_clean_text( $site_name ),
			'url'   => esc_url_raw( $home_url ),
			'logo'  => array(
				'@type' => 'ImageObject',
				'@id'   => esc_url_raw( $home_url ) . '#logo',
				'url'   => esc_url_raw( $logo_url ),
			),
		);

		if ( ! empty( $same_as ) ) {
			$schema['sameAs'] = array_values( array_unique( $same_as ) );
		}

		return $schema;
	}
}

if ( ! function_exists( 'rx_schema_get_website_schema' ) ) {
	/**
	 * Get WebSite schema.
	 *
	 * @return array
	 */
	function rx_schema_get_website_schema() {
		$home_url = home_url( '/' );

		return array(
			'@type'           => 'WebSite',
			'@id'             => esc_url_raw( $home_url ) . '#website',
			'url'             => esc_url_raw( $home_url ),
			'name'            => rx_schema_clean_text( get_bloginfo( 'name' ) ),
			'description'     => rx_schema_clean_text( get_bloginfo( 'description' ) ),
			'publisher'       => array(
				'@id' => esc_url_raw( $home_url ) . '#organization',
			),
			'potentialAction' => array(
				'@type'       => 'SearchAction',
				'target'      => array(
					'@type'       => 'EntryPoint',
					'urlTemplate' => esc_url_raw( home_url( '/?s={search_term_string}' ) ),
				),
				'query-input' => 'required name=search_term_string',
			),
		);
	}
}

if ( ! function_exists( 'rx_schema_get_breadcrumb_schema' ) ) {
	/**
	 * Get breadcrumb schema.
	 *
	 * @param int $post_id Post ID.
	 * @return array
	 */
	function rx_schema_get_breadcrumb_schema( $post_id ) {
		$items = array();

		$items[] = array(
			'@type'    => 'ListItem',
			'position' => 1,
			'name'     => 'Home',
			'item'     => esc_url_raw( home_url( '/' ) ),
		);

		$position = 2;

		$categories = get_the_category( $post_id );

		if ( ! empty( $categories ) && ! is_wp_error( $categories ) ) {
			$primary_category = $categories[0];

			$items[] = array(
				'@type'    => 'ListItem',
				'position' => $position,
				'name'     => rx_schema_clean_text( $primary_category->name ),
				'item'     => esc_url_raw( get_category_link( $primary_category->term_id ) ),
			);

			$position++;
		}

		$items[] = array(
			'@type'    => 'ListItem',
			'position' => $position,
			'name'     => rx_schema_clean_text( get_the_title( $post_id ) ),
			'item'     => esc_url_raw( get_permalink( $post_id ) ),
		);

		return array(
			'@type'           => 'BreadcrumbList',
			'@id'             => esc_url_raw( get_permalink( $post_id ) ) . '#breadcrumb',
			'itemListElement' => $items,
		);
	}
}

if ( ! function_exists( 'rx_schema_get_keywords' ) ) {
	/**
	 * Get post keywords from tags and categories.
	 *
	 * @param int $post_id Post ID.
	 * @return array
	 */
	function rx_schema_get_keywords( $post_id ) {
		$keywords = array();

		$tags = get_the_tags( $post_id );

		if ( ! empty( $tags ) && ! is_wp_error( $tags ) ) {
			foreach ( $tags as $tag ) {
				$keywords[] = rx_schema_clean_text( $tag->name );
			}
		}

		$categories = get_the_category( $post_id );

		if ( ! empty( $categories ) && ! is_wp_error( $categories ) ) {
			foreach ( $categories as $category ) {
				$keywords[] = rx_schema_clean_text( $category->name );
			}
		}

		return array_values( array_unique( array_filter( $keywords ) ) );
	}
}

if ( ! function_exists( 'rx_schema_get_article_section' ) ) {
	/**
	 * Get article section.
	 *
	 * @param int $post_id Post ID.
	 * @return string
	 */
	function rx_schema_get_article_section( $post_id ) {
		$categories = get_the_category( $post_id );

		if ( ! empty( $categories ) && ! is_wp_error( $categories ) ) {
			return rx_schema_clean_text( $categories[0]->name );
		}

		return 'Article';
	}
}

if ( ! function_exists( 'rx_schema_get_faq_schema' ) ) {
	/**
	 * Build FAQPage schema from post meta.
	 *
	 * Expected post meta format:
	 * rx_faq_schema = array(
	 *   array(
	 *     'question' => 'Question text',
	 *     'answer'   => 'Answer text',
	 *   ),
	 * );
	 *
	 * @param int $post_id Post ID.
	 * @return array|null
	 */
	function rx_schema_get_faq_schema( $post_id ) {
		$faqs = get_post_meta( $post_id, 'rx_faq_schema', true );

		if ( empty( $faqs ) || ! is_array( $faqs ) ) {
			return null;
		}

		$main_entity = array();

		foreach ( $faqs as $faq ) {
			if ( empty( $faq['question'] ) || empty( $faq['answer'] ) ) {
				continue;
			}

			$main_entity[] = array(
				'@type'          => 'Question',
				'name'           => rx_schema_clean_text( $faq['question'] ),
				'acceptedAnswer' => array(
					'@type' => 'Answer',
					'text'  => rx_schema_clean_text( $faq['answer'] ),
				),
			);
		}

		if ( empty( $main_entity ) ) {
			return null;
		}

		return array(
			'@type'      => 'FAQPage',
			'@id'        => esc_url_raw( get_permalink( $post_id ) ) . '#faq',
			'mainEntity' => $main_entity,
		);
	}
}

if ( ! function_exists( 'rx_schema_get_howto_schema' ) ) {
	/**
	 * Build HowTo schema from post meta.
	 *
	 * Expected post meta format:
	 * rx_howto_schema = array(
	 *   'name'        => 'How to title',
	 *   'description' => 'Short description',
	 *   'steps'       => array(
	 *      array(
	 *        'name' => 'Step title',
	 *        'text' => 'Step text',
	 *      ),
	 *   ),
	 * );
	 *
	 * @param int $post_id Post ID.
	 * @return array|null
	 */
	function rx_schema_get_howto_schema( $post_id ) {
		$howto = get_post_meta( $post_id, 'rx_howto_schema', true );

		if ( empty( $howto ) || ! is_array( $howto ) || empty( $howto['steps'] ) ) {
			return null;
		}

		$steps = array();
		$count = 1;

		foreach ( $howto['steps'] as $step ) {
			if ( empty( $step['text'] ) ) {
				continue;
			}

			$steps[] = array(
				'@type'    => 'HowToStep',
				'position' => $count,
				'name'     => ! empty( $step['name'] ) ? rx_schema_clean_text( $step['name'] ) : 'Step ' . $count,
				'text'     => rx_schema_clean_text( $step['text'] ),
			);

			$count++;
		}

		if ( empty( $steps ) ) {
			return null;
		}

		$name        = ! empty( $howto['name'] ) ? $howto['name'] : get_the_title( $post_id );
		$description = ! empty( $howto['description'] ) ? $howto['description'] : rx_schema_get_excerpt( $post_id );

		return array(
			'@type'       => 'HowTo',
			'@id'         => esc_url_raw( get_permalink( $post_id ) ) . '#howto',
			'name'        => rx_schema_clean_text( $name ),
			'description' => rx_schema_clean_text( $description ),
			'step'        => $steps,
		);
	}
}

if ( ! function_exists( 'rx_schema_is_medical_article' ) ) {
	/**
	 * Detect whether current article is medical content.
	 *
	 * @param int $post_id Post ID.
	 * @return bool
	 */
	function rx_schema_is_medical_article( $post_id ) {
		$medical_meta = get_post_meta( $post_id, 'rx_is_medical_article', true );

		if ( '1' === (string) $medical_meta || 'yes' === strtolower( (string) $medical_meta ) ) {
			return true;
		}

		$categories = get_the_category( $post_id );

		if ( ! empty( $categories ) && ! is_wp_error( $categories ) ) {
			foreach ( $categories as $category ) {
				$slug = strtolower( $category->slug );
				$name = strtolower( $category->name );

				if (
					str_contains( $slug, 'medical' ) ||
					str_contains( $slug, 'health' ) ||
					str_contains( $slug, 'disease' ) ||
					str_contains( $slug, 'medicine' ) ||
					str_contains( $name, 'medical' ) ||
					str_contains( $name, 'health' ) ||
					str_contains( $name, 'disease' ) ||
					str_contains( $name, 'medicine' )
				) {
					return true;
				}
			}
		}

		return false;
	}
}

if ( ! function_exists( 'rx_schema_get_medical_extra' ) ) {
	/**
	 * Get optional medical schema fields from post meta.
	 *
	 * Useful meta keys:
	 * - rx_medical_condition
	 * - rx_medical_specialty
	 * - rx_medical_audience
	 * - rx_reviewed_by
	 * - rx_reviewed_by_url
	 * - rx_last_medical_review_date
	 *
	 * @param int $post_id Post ID.
	 * @return array
	 */
	function rx_schema_get_medical_extra( $post_id ) {
		$extra = array();

		$condition   = get_post_meta( $post_id, 'rx_medical_condition', true );
		$specialty   = get_post_meta( $post_id, 'rx_medical_specialty', true );
		$audience    = get_post_meta( $post_id, 'rx_medical_audience', true );
		$reviewer    = get_post_meta( $post_id, 'rx_reviewed_by', true );
		$reviewerurl = get_post_meta( $post_id, 'rx_reviewed_by_url', true );
		$review_date = get_post_meta( $post_id, 'rx_last_medical_review_date', true );

		if ( ! empty( $condition ) ) {
			$extra['about'] = array(
				'@type' => 'MedicalCondition',
				'name'  => rx_schema_clean_text( $condition ),
			);
		}

		if ( ! empty( $specialty ) ) {
			$extra['medicalSpecialty'] = rx_schema_clean_text( $specialty );
		}

		if ( ! empty( $audience ) ) {
			$extra['audience'] = array(
				'@type' => 'MedicalAudience',
				'name'  => rx_schema_clean_text( $audience ),
			);
		}

		if ( ! empty( $reviewer ) ) {
			$reviewed_by = array(
				'@type' => 'Person',
				'name'  => rx_schema_clean_text( $reviewer ),
			);

			if ( ! empty( $reviewerurl ) && filter_var( $reviewerurl, FILTER_VALIDATE_URL ) ) {
				$reviewed_by['url'] = esc_url_raw( $reviewerurl );
			}

			$extra['reviewedBy'] = $reviewed_by;
		}

		if ( ! empty( $review_date ) ) {
			$timestamp = strtotime( $review_date );

			if ( $timestamp ) {
				$extra['lastReviewed'] = gmdate( 'c', $timestamp );
			}
		}

		return $extra;
	}
}

if ( ! function_exists( 'rx_schema_get_article_schema' ) ) {
	/**
	 * Build main article schema.
	 *
	 * @param int $post_id Post ID.
	 * @return array
	 */
	function rx_schema_get_article_schema( $post_id ) {
		$post       = get_post( $post_id );
		$permalink  = get_permalink( $post_id );
		$home_url   = home_url( '/' );
		$author_id  = (int) $post->post_author;
		$image      = rx_schema_get_post_image( $post_id );
		$is_medical = rx_schema_is_medical_article( $post_id );

		$schema_type = $is_medical ? 'MedicalWebPage' : 'Article';

		/**
		 * Allow developer override:
		 * add_filter( 'rx_schema_article_type', function() { return 'BlogPosting'; } );
		 */
		$schema_type = apply_filters( 'rx_schema_article_type', $schema_type, $post_id );

		$schema = array(
			'@type'             => $schema_type,
			'@id'               => esc_url_raw( $permalink ) . '#article',
			'isPartOf'          => array(
				'@id' => esc_url_raw( $permalink ) . '#webpage',
			),
			'mainEntityOfPage'  => array(
				'@id' => esc_url_raw( $permalink ) . '#webpage',
			),
			'headline'          => rx_schema_clean_text( get_the_title( $post_id ) ),
			'description'       => rx_schema_get_excerpt( $post_id ),
			'datePublished'     => get_the_date( DATE_W3C, $post_id ),
			'dateModified'      => get_the_modified_date( DATE_W3C, $post_id ),
			'author'            => array(
				'@id' => esc_url_raw( get_author_posts_url( $author_id ) ) . '#author',
			),
			'publisher'         => array(
				'@id' => esc_url_raw( $home_url ) . '#organization',
			),
			'inLanguage'        => get_bloginfo( 'language' ),
			'url'               => esc_url_raw( $permalink ),
			'articleSection'    => rx_schema_get_article_section( $post_id ),
			'wordCount'         => rx_schema_get_word_count( $post_id ),
			'timeRequired'      => rx_schema_get_reading_time( $post_id ),
			'copyrightYear'     => get_the_date( 'Y', $post_id ),
			'copyrightHolder'   => array(
				'@id' => esc_url_raw( $home_url ) . '#organization',
			),
			'speakable'         => array(
				'@type' => 'SpeakableSpecification',
				'cssSelector' => array(
					'h1',
					'.entry-title',
					'.post-title',
					'.entry-content p:first-of-type',
				),
			),
		);

		if ( ! empty( $image ) ) {
			$schema['image'] = $image;
			$schema['thumbnailUrl'] = $image['url'];
		}

		$keywords = rx_schema_get_keywords( $post_id );

		if ( ! empty( $keywords ) ) {
			$schema['keywords'] = implode( ', ', $keywords );
		}

		$medical_extra = rx_schema_get_medical_extra( $post_id );

		if ( ! empty( $medical_extra ) ) {
			$schema = array_merge( $schema, $medical_extra );
		}

		return apply_filters( 'rx_schema_article_schema', $schema, $post_id );
	}
}

if ( ! function_exists( 'rx_schema_get_webpage_schema' ) ) {
	/**
	 * Get WebPage schema.
	 *
	 * @param int $post_id Post ID.
	 * @return array
	 */
	function rx_schema_get_webpage_schema( $post_id ) {
		$permalink = get_permalink( $post_id );
		$image     = rx_schema_get_post_image( $post_id );

		$schema = array(
			'@type'              => rx_schema_is_medical_article( $post_id ) ? 'MedicalWebPage' : 'WebPage',
			'@id'                => esc_url_raw( $permalink ) . '#webpage',
			'url'                => esc_url_raw( $permalink ),
			'name'               => rx_schema_clean_text( get_the_title( $post_id ) ),
			'description'        => rx_schema_get_excerpt( $post_id ),
			'isPartOf'           => array(
				'@id' => esc_url_raw( home_url( '/' ) ) . '#website',
			),
			'primaryImageOfPage' => ! empty( $image ) ? array(
				'@id' => esc_url_raw( $image['url'] ) . '#primaryimage',
			) : null,
			'breadcrumb'         => array(
				'@id' => esc_url_raw( $permalink ) . '#breadcrumb',
			),
			'inLanguage'         => get_bloginfo( 'language' ),
			'datePublished'      => get_the_date( DATE_W3C, $post_id ),
			'dateModified'       => get_the_modified_date( DATE_W3C, $post_id ),
		);

		return array_filter( $schema );
	}
}

if ( ! function_exists( 'rx_schema_output_article_jsonld' ) ) {
	/**
	 * Output complete JSON-LD graph for single posts.
	 *
	 * @return void
	 */
	function rx_schema_output_article_jsonld() {
		if ( ! is_singular( 'post' ) ) {
			return;
		}

		if ( is_admin() || is_feed() || wp_doing_ajax() ) {
			return;
		}

		global $post;

		if ( ! $post instanceof WP_Post ) {
			return;
		}

		$post_id   = get_the_ID();
		$author_id = (int) get_post_field( 'post_author', $post_id );

		$graph = array();

		$graph[] = rx_schema_get_organization_schema();
		$graph[] = rx_schema_get_website_schema();
		$graph[] = rx_schema_get_author_schema( $author_id );
		$graph[] = rx_schema_get_webpage_schema( $post_id );
		$graph[] = rx_schema_get_breadcrumb_schema( $post_id );
		$graph[] = rx_schema_get_article_schema( $post_id );

		$faq_schema = rx_schema_get_faq_schema( $post_id );

		if ( ! empty( $faq_schema ) ) {
			$graph[] = $faq_schema;
		}

		$howto_schema = rx_schema_get_howto_schema( $post_id );

		if ( ! empty( $howto_schema ) ) {
			$graph[] = $howto_schema;
		}

		/**
		 * Final graph filter.
		 */
		$graph = apply_filters( 'rx_schema_article_graph', $graph, $post_id );

		$json_ld = array(
			'@context' => 'https://schema.org',
			'@graph'   => array_values( array_filter( $graph ) ),
		);

		echo "\n<!-- RX Theme Advanced Article Schema -->\n";
		echo '<script type="application/ld+json">' . wp_json_encode(
			$json_ld,
			JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT
		) . '</script>' . "\n";
	}
}

add_action( 'wp_head', 'rx_schema_output_article_jsonld', 30 );

str_contains( $slug, 'medical' )

false !== strpos( $slug, 'medical' )