<?php
/**
 * Works out, for whatever the visitor is looking at, the effective SEO values:
 * a custom value if someone set one, otherwise the automatic one.
 */

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

class SXSEO_Context {

	private static $cache = null;

	public static function reset() {
		self::$cache = null;
	}

	/** Context for the main query. */
	public static function current() {
		if ( null === self::$cache ) {
			self::$cache = self::build();
		}
		return self::$cache;
	}

	// ------------------------------------------------------------------ posts

	/** Effective values for a post, usable in the front end, admin audit and REST. */
	public static function for_post( $post ) {
		$post = get_post( $post );
		if ( ! $post ) {
			return array();
		}
		$id      = $post->ID;
		$content = $post->post_content;
		$f       = SXSEO_Fields::all_custom( $id );
		$terms   = self::term_names( $post );
		$is_home = ( 'page' === get_option( 'show_on_front' ) && (int) get_option( 'page_on_front' ) === $id );

		$title_plain = sxseo_title_text( $post );
		$focus       = '' !== $f['focus'] ? $f['focus'] : SXSEO_Auto::focus( $title_plain );

		$pt   = 'page' === $post->post_type ? 'page' : 'post';
		$tpl  = $is_home ? sxseo_opt( 'title_home' ) : sxseo_opt( 'title_' . $pt );
		$vars = array(
			'title'    => $title_plain,
			'category' => $terms['primary'],
			'author'   => get_the_author_meta( 'display_name', $post->post_author ),
			'date'     => get_the_date( '', $post ),
			'focus'    => $focus,
		);
		$title = '' !== $f['title'] ? SXSEO_Auto::render_template( $f['title'], $vars ) : SXSEO_Auto::render_template( $tpl, $vars );

		$desc_auto = SXSEO_Auto::description( $content, has_excerpt( $post ) ? $post->post_excerpt : '' );
		if ( $is_home && '' !== (string) sxseo_opt( 'home_description' ) ) {
			$desc_auto = (string) sxseo_opt( 'home_description' );
		}
		if ( '' === trim( $desc_auto ) ) {
			// Template-driven pages have no editor content: describe them with their title and the site's own summary.
			$site_desc = (string) sxseo_opt( 'home_description' ) ?: get_bloginfo( 'description' );
			$desc_auto = sxseo_trim( trim( $title_plain . ( '' !== $site_desc ? ' — ' . $site_desc : '' ) ), (int) sxseo_opt( 'description_len', 155 ) );
		}
		$desc = '' !== $f['desc'] ? SXSEO_Auto::render_template( $f['desc'], $vars ) : $desc_auto;

		$keywords = '' !== $f['keywords']
			? array_values( array_filter( array_map( 'trim', explode( ',', sxseo_lower( $f['keywords'] ) ) ) ) )
			: SXSEO_Auto::keywords( $title_plain, $content, $terms['all'], $focus );

		$image = '' !== $f['og_image'] ? $f['og_image'] : self::post_image( $post );

		$url = '' !== $f['canonical'] ? $f['canonical'] : get_permalink( $post );

		$robots = array();
		if ( '1' === $f['noindex'] || post_password_required( $post ) || 'publish' !== $post->post_status ) {
			$robots[] = 'noindex';
		}
		if ( '1' === $f['nofollow'] ) {
			$robots[] = 'nofollow';
		}
		foreach ( array( 'noarchive', 'nosnippet', 'noimageindex' ) as $adv ) {
			if ( '1' === $f[ $adv ] ) {
				$robots[] = $adv;
			}
		}

		return array(
			'id'        => $id,
			'title'     => $title,
			'title_auto'=> '' === $f['title'],
			'desc'      => $desc,
			'desc_auto' => '' === $f['desc'],
			'focus'     => $focus,
			'focus_auto'=> '' === $f['focus'],
			'keywords'  => $keywords,
			'image'     => $image,
			'url'       => $url,
			'robots'    => $robots,
			'og_title'  => '' !== $f['og_title'] ? $f['og_title'] : ( '' !== $f['title'] ? $title : $title_plain ),
			'og_desc'   => '' !== $f['og_desc'] ? $f['og_desc'] : $desc,
			'custom'    => $f,
			'terms'     => $terms,
		);
	}

	public static function term_names( $post ) {
		$all     = array();
		$primary = '';
		foreach ( get_object_taxonomies( $post->post_type, 'objects' ) as $tax ) {
			if ( ! $tax->public ) {
				continue;
			}
			$terms = get_the_terms( $post, $tax->name );
			if ( ! $terms || is_wp_error( $terms ) ) {
				continue;
			}
			foreach ( $terms as $t ) {
				if ( 'uncategorized' === $t->slug ) {
					continue;
				}
				$all[] = $t->name;
				if ( '' === $primary && 'category' === $tax->name ) {
					$primary = $t->name;
				}
			}
		}
		return array( 'all' => array_values( array_unique( $all ) ), 'primary' => $primary );
	}

	public static function post_image( $post ) {
		$thumb = get_post_thumbnail_id( $post );
		if ( $thumb ) {
			$src = wp_get_attachment_image_url( $thumb, 'full' );
			if ( $src ) {
				return $src;
			}
		}
		$first = SXSEO_Auto::first_image( $post->post_content );
		if ( $first ) {
			return $first;
		}
		return (string) sxseo_opt( 'default_image', '' ) ?: (string) sxseo_opt( 'org_logo', '' );
	}

	// ---------------------------------------------------------------- request

	private static function build() {
		$c = array(
			'type'      => 'other',
			'object'    => null,
			'title'     => '',
			'desc'      => '',
			'url'       => '',
			'robots'    => array(),
			'image'     => '',
			'keywords'  => array(),
			'og_type'   => 'website',
			'og_title'  => '',
			'og_desc'   => '',
			'post'      => null,
			'ctx'       => array(),
		);
		$paged = max( 1, (int) get_query_var( 'paged' ), (int) get_query_var( 'page' ) );
		$page_suffix = $paged > 1 ? ' ' . sprintf( /* translators: %d: page number */ __( 'Page %d', 'sentrixa-seo' ), $paged ) : '';
		$site = array( 'sitename' => get_bloginfo( 'name' ), 'tagline' => get_bloginfo( 'description' ) );

		if ( is_singular() ) {
			$post = get_queried_object();
			if ( $post instanceof WP_Post ) {
				$ctx = self::for_post( $post );
				$c   = array_merge(
					$c,
					array(
						'type'     => is_front_page() ? 'front' : ( 'page' === $post->post_type ? 'page' : 'post' ),
						'object'   => $post,
						'post'     => $post,
						'ctx'      => $ctx,
						'title'    => $ctx['title'],
						'desc'     => $ctx['desc'],
						'url'      => $ctx['url'],
						'robots'   => $ctx['robots'],
						'image'    => $ctx['image'],
						'keywords' => $ctx['keywords'],
						'og_type'  => 'post' === $post->post_type || 'article' === $post->post_type ? 'article' : 'website',
						'og_title' => $ctx['og_title'],
						'og_desc'  => $ctx['og_desc'],
					)
				);
				if ( is_attachment() ) {
					$c['robots'][] = 'noindex';
				}
				$page = (int) get_query_var( 'page' );
				if ( $page > 1 && '' === $ctx['custom']['canonical'] ) {
					$c['url'] = trailingslashit( get_permalink( $post ) ) . user_trailingslashit( (string) $page, 'single_paged' );
				}
				return $c;
			}
		}

		if ( is_front_page() || is_home() ) {
			$posts_page = 'page' === get_option( 'show_on_front' ) ? (int) get_option( 'page_for_posts' ) : 0;
			if ( is_home() && $posts_page ) {
				$post  = get_post( $posts_page );
				$ctx   = self::for_post( $post );
				$title = $ctx['title'];
				$desc  = $ctx['desc'];
			} else {
				$title = SXSEO_Auto::render_template( sxseo_opt( 'title_home' ), $site );
				$desc  = (string) sxseo_opt( 'home_description' );
				if ( '' === $desc ) {
					$desc = get_bloginfo( 'description' );
				}
			}
			$c['type']     = 'home';
			$c['title']    = $title . $page_suffix;
			$c['desc']     = $desc;
			$c['url']      = $paged > 1 ? get_pagenum_link( $paged ) : ( ( is_home() && $posts_page ) ? get_permalink( $posts_page ) : home_url( '/' ) );
			$c['image']    = (string) sxseo_opt( 'default_image', '' ) ?: (string) sxseo_opt( 'org_logo', '' );
			$c['keywords'] = SXSEO_Auto::keywords( get_bloginfo( 'name' ), get_bloginfo( 'description' ), array(), '', 8 );
			$c['og_title'] = $title;
			$c['og_desc']  = $desc;
			return $c;
		}

		if ( is_category() || is_tag() || is_tax() ) {
			$term = get_queried_object();
			if ( $term instanceof WP_Term ) {
				$custom_t = (string) get_term_meta( $term->term_id, 'sxseo_title', true );
				$custom_d = (string) get_term_meta( $term->term_id, 'sxseo_desc', true );
				$title    = SXSEO_Auto::render_template( '' !== $custom_t ? $custom_t : sxseo_opt( 'title_term' ), array( 'term' => $term->name ) );
				$desc     = '' !== $custom_d ? $custom_d : sxseo_trim( sxseo_plain( term_description( $term->term_id ) ), (int) sxseo_opt( 'description_len', 155 ) );
				if ( '' === $desc ) {
					/* translators: 1: term name, 2: site name */
					$desc = sprintf( __( 'Everything on %2$s filed under %1$s.', 'sentrixa-seo' ), $term->name, get_bloginfo( 'name' ) );
				}
				$c['type']     = 'term';
				$c['object']   = $term;
				$c['title']    = $title . $page_suffix;
				$c['desc']     = $desc;
				$c['url']      = get_pagenum_link( $paged );
				$c['keywords'] = array_slice( array_unique( array_filter( array( sxseo_lower( $term->name ), sxseo_lower( get_bloginfo( 'name' ) ) ) ) ), 0, 8 );
				$c['og_title'] = $title;
				$c['og_desc']  = $desc;
				$c['image']    = (string) sxseo_opt( 'default_image', '' ) ?: (string) sxseo_opt( 'org_logo', '' );
				if ( ! sxseo_term_indexable( $term ) ) {
					$c['robots'][] = 'noindex';
				}
				return $c;
			}
		}

		if ( is_author() ) {
			$user = get_queried_object();
			$name = $user ? $user->display_name : '';
			$bio  = $user ? sxseo_plain( get_the_author_meta( 'description', $user->ID ) ) : '';
			$c['type']     = 'author';
			$c['object']   = $user;
			$c['title']    = SXSEO_Auto::render_template( sxseo_opt( 'title_author' ), array( 'author' => $name ) ) . $page_suffix;
			$c['desc']     = '' !== $bio ? sxseo_trim( $bio, 155 ) : sprintf( /* translators: %s: author */ __( 'Articles written by %s.', 'sentrixa-seo' ), $name );
			$c['url']      = get_pagenum_link( $paged );
			$c['og_title'] = $c['title'];
			$c['og_desc']  = $c['desc'];
			$c['image']    = (string) sxseo_opt( 'default_image', '' );
			$mode          = sxseo_opt( 'noindex_author', 'auto' );
			if ( '1' === (string) $mode || ( 'auto' === $mode && count( get_users( array( 'who' => 'authors', 'fields' => 'ID', 'number' => 2 ) ) ) < 2 ) ) {
				$c['robots'][] = 'noindex';
			}
			return $c;
		}

		if ( is_search() ) {
			$c['type']     = 'search';
			$c['title']    = SXSEO_Auto::render_template( sxseo_opt( 'title_search' ), array( 'searchphrase' => get_search_query( false ) ) );
			$c['url']      = home_url( '/' );
			$c['robots'][] = 'noindex';
			return $c;
		}

		if ( is_404() ) {
			$c['type']     = '404';
			$c['title']    = SXSEO_Auto::render_template( sxseo_opt( 'title_404' ), array() );
			$c['robots'][] = 'noindex';
			return $c;
		}

		if ( is_date() ) {
			$c['type']  = 'date';
			$c['title'] = SXSEO_Auto::render_template( sxseo_opt( 'title_archive' ), array( 'archive' => wp_strip_all_tags( get_the_archive_title() ) ) ) . $page_suffix;
			$c['url']   = get_pagenum_link( $paged );
			if ( sxseo_opt( 'noindex_date' ) ) {
				$c['robots'][] = 'noindex';
			}
			return $c;
		}

		if ( is_post_type_archive() ) {
			$pt             = get_queried_object();
			$name           = $pt ? $pt->labels->name : '';
			$c['type']      = 'archive';
			$c['title']     = SXSEO_Auto::render_template( sxseo_opt( 'title_archive' ), array( 'archive' => $name ) ) . $page_suffix;
			$c['desc']      = $pt && ! empty( $pt->description ) ? $pt->description : sprintf( /* translators: 1: type, 2: site */ __( '%1$s from %2$s.', 'sentrixa-seo' ), $name, get_bloginfo( 'name' ) );
			$c['url']       = get_pagenum_link( $paged );
			$c['og_title']  = $c['title'];
			$c['og_desc']   = $c['desc'];
			return $c;
		}

		return $c;
	}
}