<?php

namespace RoosterLMS\Display;

use RoosterLMS\Content\CourseVisibility;
use RoosterLMS\Content\PostTypes;
use RoosterLMS\Core\Settings;
use RoosterLMS\Domain\Services;
use RoosterLMS\Faq\FaqTarget;

defined( 'ABSPATH' ) || exit;

final class CourseJsonLd {

	public static function head(): void {
		$ld = self::ld_for_query();
		if ( array() !== $ld ) {
			wp_print_inline_script_tag( wp_json_encode( $ld, JSON_HEX_TAG | JSON_HEX_AMP | JSON_HEX_APOS | JSON_HEX_QUOT ), array( 'type' => 'application/ld+json' ) );
		}
	}

	public static function ld_for_query(): array {
		if ( ! Settings::get( 'course_jsonld_faq' ) && ! Settings::get( 'course_jsonld_rating' ) ) {
			return array();
		}
		if ( ! is_singular( PostTypes::COURSE ) ) {
			return array();
		}
		$post = get_queried_object();
		return $post instanceof \WP_Post ? self::ld( $post ) : array();
	}

	public static function ld( \WP_Post $post ): array {
		if ( 'publish' !== $post->post_status || '' !== $post->post_password ) {
			return array();
		}
		$course_id = Services::courses()->resolve_post( (int) $post->ID );
		$page      = CoursePage::for( $course_id );
		if ( null === $page || ! $page->course->is_active() || CourseVisibility::PUBLIC !== $page->course->visibility ) {
			return array();
		}
		$graph = array();
		$url   = (string) get_permalink( $post );
		if ( Settings::get( 'course_jsonld_rating' ) && $page->reviews_on() && $page->rating_count > 0 && null !== $page->rating_avg && ! $page->coming_soon() ) {
			$graph[] = array(
				'@type'           => 'Course',
				'@id'             => $url . '#course',
				'name'            => wp_strip_all_tags( get_the_title( $post ) ),
				'description'     => self::plain( '' !== trim( $post->post_excerpt ) ? $post->post_excerpt : wp_trim_words( excerpt_remove_blocks( strip_shortcodes( $post->post_content ) ), 40 ) ),
				'url'             => $url,
				'provider'        => array(
					'@type'  => 'Organization',
					'name'   => wp_strip_all_tags( (string) get_bloginfo( 'name' ) ),
					'sameAs' => home_url( '/' ),
				),
				'aggregateRating' => array(
					'@type'       => 'AggregateRating',
					'ratingValue' => round( $page->rating_avg, 2 ),
					'ratingCount' => $page->rating_count,
					'bestRating'  => 5,
					'worstRating' => 1,
				),
			);
		}
		if ( Settings::get( 'course_jsonld_faq' ) && $page->faq_links > 0 && ! $page->hides_details( 0 ) ) {
			$faqs  = FaqQuery::for_target( FaqTarget::COURSE, $course_id );
			$texts = Services::faqs()->texts( $faqs );
			$main  = array();
			foreach ( $faqs as $faq ) {
				$question = self::plain( (string) ( $texts[ $faq->id ]['question'] ?? $faq->question ) );
				$answer   = self::plain( (string) ( $texts[ $faq->id ]['answer'] ?? $faq->answer ) );
				if ( '' !== $question && '' !== $answer ) {
					$main[] = array(
						'@type'          => 'Question',
						'name'           => $question,
						'acceptedAnswer' => array(
							'@type' => 'Answer',
							'text'  => $answer,
						),
					);
				}
			}
			if ( array() !== $main ) {
				$graph[] = array(
					'@type'      => 'FAQPage',
					'@id'        => $url . '#faq',
					'mainEntity' => $main,
				);
			}
		}
		if ( array() === $graph ) {
			return array();
		}
		return array(
			'@context' => 'https://schema.org',
			'@graph'   => $graph,
		);
	}

	private static function plain( string $html ): string {
		return trim( (string) preg_replace( '/\s+/u', ' ', html_entity_decode( wp_strip_all_tags( $html ), ENT_QUOTES, 'UTF-8' ) ) );
	}
}