<?php
/**
 * The Singular Class
 *
 * @since      1.0.22
 * @package    RankMath
 * @subpackage RankMath\Paper
 * @author     Rank Math <support@rankmath.com>
 */

namespace RankMath\Paper;

use RankMath\Post;
use RankMath\Helper;
use RankMath\Helpers\Security;
use RankMath\Helpers\Str;

defined( 'ABSPATH' ) || exit;

/**
 * Singular class.
 */
class Singular implements IPaper {

	/**
	 * Post object.
	 *
	 * @var WP_Post
	 */
	private $object;

	/**
	 * Retrieves the SEO title.
	 *
	 * @return string
	 */
	public function title() {
		return $this->get_post_title( $this->object );
	}

	/**
	 * Retrieves the SEO description.
	 *
	 * @return string
	 */
	public function description() {
		return $this->get_post_description( $this->object );
	}

	/**
	 * Retrieves the robots.
	 *
	 * @return string
	 */
	public function robots() {
		return $this->get_post_robots( $this->object );
	}

	/**
	 * Retrieves the advanced robots.
	 *
	 * @return array
	 */
	public function advanced_robots() {
		return $this->get_post_advanced_robots( $this->object );
	}

	/**
	 * Retrieves the canonical URL.
	 *
	 * @return array
	 */
	public function canonical() {
		$object_id          = Post::get_page_id();
		$canonical          = get_permalink( $object_id );
		$canonical_unpaged  = $canonical;
		$canonical_override = Post::get_meta( 'canonical_url', $object_id );

		/**
		 * Fix paginated pages canonical, but only if the page is truly paginated.
		 *
		 * @copyright Copyright (C) 2008-2019, Yoast BV
		 * The following code is a derivative work of the code from the Yoast(https://github.com/Yoast/wordpress-seo/), which is licensed under GPL v3.
		 */
		if ( is_singular() && get_query_var( 'page' ) > 1 ) {
			$num_pages = ( substr_count( get_queried_object()->post_content, '<!--nextpage-->' ) + 1 );
			if ( $num_pages && get_query_var( 'page' ) <= $num_pages ) {
				global $wp_rewrite;
				$canonical = ! $wp_rewrite->using_permalinks() ? Security::add_query_arg_raw( 'page', get_query_var( 'page' ), $canonical ) :
					user_trailingslashit( trailingslashit( $canonical ) . get_query_var( 'page' ) );
			}
		}

		return [
			'canonical'          => $canonical,
			'canonical_unpaged'  => $canonical,
			'canonical_override' => $canonical_override,
		];
	}

	/**
	 * Retrieves meta keywords.
	 *
	 * @return string The focus keywords.
	 */
	public function keywords() {
		return Post::get_meta( 'focus_keyword', $this->object->ID );
	}

	/**
	 * Set post object.
	 *
	 * @param WP_Post $post Current post object.
	 */
	public function set_object( $post ) {
		$this->object = $post;
	}

	/**
	 * Get the SEO title set in the post metabox.
	 *
	 * @param object|null $post Post object to retrieve the title for.
	 *
	 * @return string
	 */
	protected function get_post_title( $post = null ) {
		if ( ! is_object( $post ) ) {
			return Paper::get_from_options( '404_title', [], esc_html__( 'Page not found', 'rank-math' ) );
		}

		$title = Post::get_meta( 'title', $post->ID );
		if ( '' !== $title ) {
			return $title;
		}

		$post_type = isset( $post->post_type ) ? $post->post_type : $post->query_var;
		return Paper::get_from_options( "pt_{$post_type}_title", $post, '%title% %sep% %sitename%' );
	}

	/**
	 * Retrieves the SEO description set in the post metabox.
	 *
	 * Retrieve in this order:
	 *     1. Custom meta description set for the post in SERP field
	 *     2. Excerpt
	 *     3. Description template set in the Titles & Meta
	 *     4. Paragraph with the focus keyword
	 *     5. The First paragraph of the content
	 *
	 * @param object|null $post Object to retrieve the description from.
	 *
	 * @return string The SEO description for the specified object, or queried object if not supplied.
	 */
	protected function get_post_description( $post = null ) {
		if ( ! is_object( $post ) ) {
			return '';
		}

		// 1. Custom meta description set for the post in SERP field.
		$description = Post::get_meta( 'description', $post->ID );
		if ( '' !== $description ) {
			return $description;
		}

		// 2. Excerpt
		if ( ! empty( $post->post_excerpt ) ) {
			return $post->post_excerpt;
		}

		// 3. Description template set in the Titles & Meta.
		$post_type = isset( $post->post_type ) ? $post->post_type : $post->query_var;

		return Str::truncate( Paper::get_from_options( "pt_{$post_type}_description", $post ), 160 );
	}

	/**
	 * Retrieves the robots set in the post metabox.
	 *
	 * @param object|null $post Object to retrieve the robots data from.
	 *
	 * @return string The robots for the specified object, or queried object if not supplied.
	 */
	protected function get_post_robots( $post = null ) {
		if ( ! is_object( $post ) ) {
			return [];
		}

		$post_type = $post->post_type;
		$robots    = Paper::robots_combine( Post::get_meta( 'robots', $post->ID ) );
		if ( empty( $robots ) && Helper::get_settings( "titles.pt_{$post_type}_custom_robots" ) ) {
			$robots = Paper::robots_combine( Helper::get_settings( "titles.pt_{$post_type}_robots" ), true );
		}

		// `noindex` these conditions.
		$noindex_private            = 'private' === $post->post_status;
		$no_index_subpages          = is_paged() && Helper::get_settings( 'titles.noindex_paginated_pages' );
		$noindex_password_protected = ! empty( $post->post_password ) && Helper::get_settings( 'titles.noindex_password_protected' );

		if ( $noindex_private || $noindex_password_protected || $no_index_subpages ) {
			$robots['index'] = 'noindex';
		}

		return $robots;
	}

	/**
	 * Retrieves the advanced robots set in the post metabox.
	 *
	 * @param object|null $post Object to retrieve the robots data from.
	 *
	 * @return string The robots for the specified object, or queried object if not supplied.
	 */
	protected function get_post_advanced_robots( $post = null ) {
		if ( ! is_object( $this->object ) ) {
			return [];
		}

		$post_type = $this->object->post_type;
		$robots    = Paper::advanced_robots_combine( Post::get_meta( 'advanced_robots', $this->object->ID ) );
		if ( ! is_array( $robots ) && Helper::get_settings( "titles.pt_{$post_type}_custom_robots" ) ) {
			$robots = Paper::advanced_robots_combine( Helper::get_settings( "titles.pt_{$post_type}_advanced_robots" ), true );
		}

		return $robots;
	}
}
