<?php

namespace RoosterLMS\Blocks;

use RoosterLMS\Content\PostTypes;
use RoosterLMS\Domain\Services;
use RoosterLMS\Routing\RouteContext;

defined( 'ABSPATH' ) || exit;

final class LiveContent {

	private static bool $registered = false;

	public function register(): void {
		if ( self::$registered ) {
			return;
		}
		self::$registered = true;
		add_filter( 'the_content', array( self::class, 'content' ), 8, 1 );
		add_action( 'rooster_lms_live_sessions_changed', array( LiveData::class, 'invalidate_units' ), 10, 0 );
	}

	public static function content( $content ) {
		if ( ! is_string( $content ) || ! is_singular( array( PostTypes::LESSON, PostTypes::QUIZ ) ) ) {
			return $content;
		}
		$post = get_post();
		if ( ! $post instanceof \WP_Post || (int) get_queried_object_id() !== (int) $post->ID || doing_filter( 'get_the_excerpt' ) || doing_filter( 'wp_trim_excerpt' ) || doing_action( 'wp_head' ) ) {
			return $content;
		}
		if ( has_block( 'rooster-lms/live-session', $content ) || has_shortcode( $content, 'rooster_lms_live_session' ) ) {
			return $content;
		}
		$live = LiveData::live_units();
		if ( array() === $live ) {
			return $content;
		}
		$course_id = RouteContext::course_id();
		$unit_id   = RouteContext::unit_id();
		if ( $unit_id > 0 && ! isset( $live[ $unit_id ] ) ) {
			return $content;
		}
		if ( $course_id <= 0 || $unit_id <= 0 ) {
			$item      = Context::single_placement( (int) $post->ID );
			$course_id = null === $item ? 0 : $item->course_id;
			$unit_id   = null === $item ? 0 : $item->unit_id;
		}
		if ( $course_id <= 0 || ! isset( $live[ $unit_id ] ) || array() === ( LiveData::for_course( $course_id )[ $unit_id ] ?? array() ) ) {
			return $content;
		}
		if ( ! Services::gate()->can_open_post( get_current_user_id(), (int) $post->ID )->allowed ) {
			return $content;
		}
		return $content . ( BlockRegistry::is_registered( 'live-session' )
			? "\n<!-- wp:rooster-lms/live-session /-->\n"
			: Render\LiveSession::render( array() ) );
	}
}