<?php

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

/**
 * Handle Frontend Schema Injection.
 * Outputs JSON-LD with partner relationships for AI search engines.
 */
class AISH_Frontend {
	/**
	 * Whether partner data was injected through SEO plugin filters.
	 *
	 * @var bool
	 */
	private $seo_filter_injected = false;

	/**
	 * Constructor.
	 */
	public function __construct() {
		add_action( 'wp_head', array( $this, 'inject_schema' ), 99 );
		add_filter( 'wpseo_schema_graph', array( $this, 'filter_yoast_schema' ) );
		add_filter( 'rank_math/json_ld', array( $this, 'filter_rank_math_schema' ) );
	}

	/**
	 * Check if schema should be output on the current page.
	 *
	 * @return bool
	 */
	private function should_output() {
		$scope = carbon_get_theme_option( 'aish_output_scope' );

		if ( 'front_page' === $scope ) {
			return is_front_page();
		}

		// 'all_pages' - output everywhere.
		return true;
	}

	/**
	 * Get the configured schema entity type.
	 *
	 * @return string 'Organization' or 'Person'.
	 */
	private function get_schema_type() {
		$type = carbon_get_theme_option( 'aish_schema_type' );
		return $type ? $type : 'Organization';
	}

	/**
	 * Whether the optional developer support schema is enabled.
	 *
	 * @return bool
	 */
	public static function is_protocol_support_enabled() {
		return function_exists( 'carbon_get_theme_option' ) && (bool) carbon_get_theme_option( 'aish_support_schema_enabled' );
	}

	/**
	 * Whether the site consented to future public listing usage.
	 *
	 * @return bool
	 */
	public static function has_protocol_public_listing_consent() {
		return function_exists( 'carbon_get_theme_option' ) && (bool) carbon_get_theme_option( 'aish_support_public_listing_consent' );
	}

	/**
	 * Get a reusable payload for future protocol-directory integrations.
	 *
	 * @return array
	 */
	public static function get_protocol_support_payload() {
		$site_url = get_site_url();
		$name     = trim( (string) carbon_get_theme_option( 'aish_my_business_name' ) );
		$industry = trim( (string) carbon_get_theme_option( 'aish_my_industry' ) );
		$type     = carbon_get_theme_option( 'aish_schema_type' );
		$secret   = get_option( 'aish_site_secret', '' );
		$public_id = $secret ? substr( hash( 'sha256', $secret ), 0, 16 ) : '';

		if ( '' === $name ) {
			$parsed_name = wp_parse_url( $site_url, PHP_URL_HOST );
			$name        = is_string( $parsed_name ) && '' !== $parsed_name ? $parsed_name : get_bloginfo( 'name' );
		}

		return array(
			'enabled'                => self::is_protocol_support_enabled(),
			'public_listing_consent' => self::has_protocol_public_listing_consent(),
			'site_url'               => $site_url,
			'site_name'              => $name,
			'industry'               => $industry,
			'schema_type'            => 'Person' === $type ? 'Person' : 'Organization',
			'public_id'              => $public_id,
			'protocol_url'           => AISH_REST::get_protocol_support_target_url(),
			'protocol_name'          => AISH_REST::get_protocol_support_target_name(),
		);
	}

	/**
	 * Get active partners as Schema.org entities.
	 *
	 * @return array
	 */
	private function get_partners_data() {
		$partners        = AISH_Partner_Store::get_all();
		$active_partners = array();

		if ( ! empty( $partners ) ) {
			foreach ( $partners as $partner ) {
				if ( isset( $partner['status'] ) && 'active' === $partner['status'] ) {
					$relation_type = isset( $partner['my_relation_to_partner'] )
						? AISH_REST::sanitize_relation_type( $partner['my_relation_to_partner'] )
						: 'collaboration';
					$relation_prop = $this->map_relation_to_schema_property( $relation_type );
					$entry_type    = ( ! empty( $partner['partner_type'] ) && 'Person' === $partner['partner_type'] ) ? 'Person' : 'Organization';
					$entry         = array(
						'@type' => $entry_type,
						'url'   => esc_url( $partner['url'] ),
					);

					if ( ! empty( $partner['partner_name'] ) ) {
						$entry['name'] = sanitize_text_field( $partner['partner_name'] );
					}

					if ( ! isset( $active_partners[ $relation_prop ] ) ) {
						$active_partners[ $relation_prop ] = array();
					}

					$active_partners[ $relation_prop ][] = $entry;
				}
			}
		}

		return $active_partners;
	}

	/**
	 * Get my identity data as a Schema.org entity.
	 *
	 * @return array
	 */
	private function get_my_identity() {
		$name = trim( (string) carbon_get_theme_option( 'aish_my_business_name' ) );
		if ( '' === $name ) {
			$name = get_bloginfo( 'name' );
		}

		$identity = array(
			'@context' => 'https://schema.org',
			'@type'    => $this->get_schema_type(),
			'name'     => $name,
			'url'      => get_site_url(),
		);

		$industry = carbon_get_theme_option( 'aish_my_industry' );
		if ( ! empty( $industry ) ) {
			$identity['description'] = $industry;
		}

		// Generate dynamic proofs as identifiers for active partners only.
		$proofs = $this->get_identity_proofs();
		if ( ! empty( $proofs ) ) {
			$identity['identifier'] = $proofs;
		}
		return $identity;
	}

	/**
	 * Inject standalone Schema into wp_head.
	 * Falls back to standalone output when SEO plugin filters didn't inject partner data.
	 */
	public function inject_schema() {
		if ( ! $this->should_output() ) {
			return;
		}

		$seo_active = defined( 'WPSEO_VERSION' ) || defined( 'RANK_MATH_VERSION' );
		if ( ! ( $seo_active && $this->seo_filter_injected ) ) {
			$identity = $this->get_my_identity();
			$partners = $this->get_partners_data();

			if ( ! empty( $partners ) ) {
				foreach ( $partners as $relation_prop => $entries ) {
					$identity[ $relation_prop ] = $entries;
				}
			}

			$this->render_json_ld_script( $identity );
		}

		$support_schema = $this->get_protocol_support_schema();
		if ( ! empty( $support_schema ) ) {
			$this->render_json_ld_script( $support_schema );
		}
	}

	/**
	 * Build the independent protocol support Schema node.
	 *
	 * @return array
	 */
	private function get_protocol_support_schema() {
		if ( ! self::is_protocol_support_enabled() ) {
			return array();
		}

		$payload = self::get_protocol_support_payload();

		return array(
			'@context'  => 'https://schema.org',
			'@type'     => 'CreativeWork',
			'@id'       => trailingslashit( $payload['site_url'] ) . '#aish-protocol-support',
			'name'      => __( 'AI Semantic Handshake Protocol Support', 'ai-semantic-handshake' ),
			'publisher' => array(
				'@type' => $payload['schema_type'],
				'name'  => $payload['site_name'],
				'url'   => $payload['site_url'],
			),
			'isBasedOn' => array(
				'@type' => 'CreativeWork',
				'name'  => __( 'AI Semantic Handshake Protocol', 'ai-semantic-handshake' ),
				'url'   => $payload['protocol_url'],
			),
			'mentions'  => array(
				array(
					'@type' => 'WebSite',
					'name'  => $payload['protocol_name'],
					'url'   => $payload['protocol_url'],
				),
			),
		);
	}

	/**
	 * Render a JSON-LD script block.
	 *
	 * @param array $data JSON-LD payload.
	 * @return void
	 */
	private function render_json_ld_script( $data ) {
		if ( empty( $data ) || ! is_array( $data ) ) {
			return;
		}

		$json = wp_json_encode(
			$data,
			JSON_HEX_TAG | JSON_HEX_AMP | JSON_HEX_APOS | JSON_HEX_QUOT
		);
		if ( ! $json ) {
			return;
		}

		// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- Safe JSON generated for application/ld+json script context.
		echo "\n<script type=\"application/ld+json\">{$json}</script>\n";
	}

	/**
	 * Filter Yoast SEO Schema graph.
	 *
	 * @param array $data Schema graph pieces.
	 * @return array
	 */
	public function filter_yoast_schema( $data ) {
		if ( ! $this->should_output() ) {
			return $data;
		}

		$partners = $this->get_partners_data();
		$proofs   = $this->get_identity_proofs();

		foreach ( $data as &$node ) {
			if ( ! isset( $node['@type'] ) ) {
				continue;
			}

			$type   = $node['@type'];
			$is_org = ( is_array( $type ) && ( in_array( 'Organization', $type, true ) || in_array( 'Person', $type, true ) ) )
			       || 'Organization' === $type
			       || 'Person' === $type;

			if ( $is_org ) {
				// Inject identifier proofs.
				if ( ! empty( $proofs ) ) {
					$node['identifier'] = $proofs;
				}

				// Inject partner relationships.
				if ( ! empty( $partners ) ) {
					foreach ( $partners as $relation_prop => $entries ) {
						$node[ $relation_prop ] = $entries;
					}
				}
				$this->seo_filter_injected = true;
				break;
			}
		}

		return $data;
	}

	/**
	 * Filter Rank Math Schema.
	 *
	 * @param array $data Schema data.
	 * @return array
	 */
	public function filter_rank_math_schema( $data ) {
		if ( ! $this->should_output() ) {
			return $data;
		}

		$partners = $this->get_partners_data();
		$proofs   = $this->get_identity_proofs();

		// Rank Math may use 'Organization' or 'Person' as top-level keys.
		$entity_types = array( 'Organization', 'Person' );

		foreach ( $entity_types as $type ) {
			if ( isset( $data[ $type ] ) ) {
				if ( ! empty( $proofs ) ) {
					$data[ $type ]['identifier'] = $proofs;
				}
				if ( ! empty( $partners ) ) {
					foreach ( $partners as $relation_prop => $entries ) {
						$data[ $type ][ $relation_prop ] = $entries;
					}
				}
				$this->seo_filter_injected = true;
				break;
			}
		}

		return $data;
	}

	/**
	 * Map relation type to schema property.
	 *
	 * @param string $relation_type Internal relation type.
	 * @return string
	 */
	private function map_relation_to_schema_property( $relation_type ) {
		$map = array(
			'sister_site'             => 'sameAs',
			'media_mention'           => 'mentions',
			'friendly_recommendation' => 'mentions',
			'collaboration'           => 'knowsAbout',
			'client'                  => 'knowsAbout',
			'vendor'                  => 'knowsAbout',
			'strategic_partner'       => 'knowsAbout',
			'community_peer'          => 'knowsAbout',
		);

		$relation_type = AISH_REST::sanitize_relation_type( $relation_type );
		return isset( $map[ $relation_type ] ) ? $map[ $relation_type ] : 'knowsAbout';
	}

	/**
	 * Get identity proofs for active partners only.
	 *
	 * @return array Array of SHA-256 proof hashes.
	 */
	private function get_identity_proofs() {
		$partners = AISH_Partner_Store::get_all();
		$proofs   = array();

		if ( ! empty( $partners ) ) {
			foreach ( $partners as $partner ) {
				if ( ! empty( $partner['url'] ) && isset( $partner['status'] ) && 'active' === $partner['status'] ) {
					$proofs[] = AISH_REST::generate_proof( $partner['url'] );
				}
			}
		}

		return $proofs;
	}
}