<?php
/**
 * Everything printed in <head>: title, description, keywords, robots, canonical, social cards, legacy meta,
 * verification codes, hreflang and the JSON-LD graph.
 */

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

class SXSEO_Head {

	public static function hook() {
		add_action( 'after_setup_theme', function () {
			add_theme_support( 'title-tag' );
		}, 99 );
		add_filter( 'pre_get_document_title', array( __CLASS__, 'title' ), 20 );
		add_filter( 'wp_robots', array( __CLASS__, 'robots' ), 20 );
		add_action( 'wp_head', array( __CLASS__, 'output' ), 1 );
		add_action( 'wp', array( __CLASS__, 'late' ) );
		add_action( 'template_redirect', array( __CLASS__, 'feed_headers' ), 1 );
		remove_action( 'wp_head', 'rel_canonical' );
		if ( sxseo_opt( 'cleanup_head' ) ) {
			remove_action( 'wp_head', 'wp_generator' );
			remove_action( 'wp_head', 'rsd_link' );
			remove_action( 'wp_head', 'wlwmanifest_link' );
			remove_action( 'wp_head', 'wp_shortlink_wp_head', 10 );
			add_filter( 'the_generator', '__return_empty_string' );
		}
		// Other SEO plugins' own output would duplicate ours; Sentrixa SEO is the single source.
		add_filter( 'wpseo_canonical', '__return_false' );
	}

	public static function late() {
		SXSEO_Context::reset();
	}

	public static function title( $title ) {
		$c = SXSEO_Context::current();
		return '' !== $c['title'] ? wptexturize( $c['title'] ) : $title;
	}

	public static function robots( $robots ) {
		$c = SXSEO_Context::current();
		if ( ! get_option( 'blog_public' ) ) {
			return $robots;
		}
		unset( $robots['noindex'], $robots['follow'], $robots['index'], $robots['nofollow'] );
		$flags = $c['robots'];
		$robots[ in_array( 'noindex', $flags, true ) ? 'noindex' : 'index' ]   = true;
		$robots[ in_array( 'nofollow', $flags, true ) ? 'nofollow' : 'follow' ] = true;
		foreach ( array( 'noarchive', 'nosnippet', 'noimageindex' ) as $adv ) {
			if ( in_array( $adv, $flags, true ) ) {
				$robots[ $adv ] = true;
			}
		}
		if ( sxseo_opt( 'robots_max' ) && ! in_array( 'noindex', $flags, true ) ) {
			unset( $robots['max-image-preview'] );
			$robots['max-image-preview'] = 'large';
			if ( ! in_array( 'nosnippet', $flags, true ) ) {
				$robots['max-snippet']       = '-1';
				$robots['max-video-preview'] = '-1';
			}
		}
		return $robots;
	}

	public static function feed_headers() {
		if ( sxseo_opt( 'feeds_noindex' ) && is_feed() ) {
			header( 'X-Robots-Tag: noindex, follow', true );
		}
	}

	private static function tag( $name, $content, $attr = 'name' ) {
		if ( '' === (string) $content ) {
			return;
		}
		echo '<meta ' . $attr . '="' . esc_attr( $name ) . '" content="' . esc_attr( $content ) . '" />' . "\n"; // phpcs:ignore WordPress.Security.EscapeOutput
	}

	public static function output() {
		$c = SXSEO_Context::current();
		if ( is_admin() || is_feed() ) {
			return;
		}
		echo "<!-- Sentrixa SEO " . esc_html( SXSEO_VERSION ) . " -->\n";

		$noindex = in_array( 'noindex', $c['robots'], true );
		self::tag( 'description', $c['desc'] );

		if ( sxseo_opt( 'meta_keywords' ) && $c['keywords'] && ! $noindex ) {
			self::tag( 'keywords', implode( ', ', $c['keywords'] ) );
		}

		// Canonical.
		if ( '' !== $c['url'] && ! is_404() && ! is_search() ) {
			echo '<link rel="canonical" href="' . esc_url( $c['url'] ) . '" />' . "\n";
		}

		self::legacy( $c );
		self::verification();
		if ( sxseo_opt( 'og' ) ) {
			self::social( $c );
		}
		if ( sxseo_opt( 'hreflang' ) && '' !== $c['url'] && ! $noindex ) {
			$lang = str_replace( '_', '-', get_locale() );
			echo '<link rel="alternate" hreflang="' . esc_attr( $lang ) . '" href="' . esc_url( $c['url'] ) . '" />' . "\n";
			echo '<link rel="alternate" hreflang="x-default" href="' . esc_url( $c['url'] ) . '" />' . "\n";
		}
		if ( ! $noindex ) {
			SXSEO_Schema::output( $c );
		}
		echo "<!-- /Sentrixa SEO -->\n";
	}

	private static function legacy( array $c ) {
		$s    = SXSEO_Settings::all();
		$name = $s['org_name'] ?: get_bloginfo( 'name' );

		if ( $s['meta_author'] ) {
			$author = '';
			if ( $c['post'] instanceof WP_Post && 'post' === $c['post']->post_type ) {
				$author = get_the_author_meta( 'display_name', $c['post']->post_author );
			}
			self::tag( 'author', $author ?: $name );
		}
		if ( $s['meta_copyright'] ) {
			self::tag( 'copyright', '© ' . gmdate( 'Y' ) . ' ' . $name );
		}
		if ( $s['meta_language'] ) {
			self::tag( 'language', str_replace( '_', '-', get_locale() ) );
			self::tag( 'content-language', str_replace( '_', '-', get_locale() ), 'http-equiv' );
		}
		if ( $s['meta_legacy'] ) {
			self::tag( 'revisit-after', '7 days' );
			self::tag( 'rating', 'general' );
			self::tag( 'distribution', 'global' );
			self::tag( 'resource-type', 'document' );
			self::tag( 'format-detection', 'telephone=yes' );
			self::tag( 'application-name', get_bloginfo( 'name' ) );
		}
		if ( $s['geo_meta'] && $s['org_lat'] && $s['org_lng'] ) {
			if ( $s['org_country'] ) {
				self::tag( 'geo.region', $s['org_country'] . ( $s['org_region'] ? '-' . $s['org_region'] : '' ) );
			}
			if ( $s['org_city'] ) {
				self::tag( 'geo.placename', $s['org_city'] );
			}
			self::tag( 'geo.position', $s['org_lat'] . ';' . $s['org_lng'] );
			self::tag( 'ICBM', $s['org_lat'] . ', ' . $s['org_lng'] );
		}
		if ( $s['dublin_core'] ) {
			self::tag( 'DC.title', $c['og_title'] ?: $c['title'] );
			self::tag( 'DC.description', $c['desc'] );
			self::tag( 'DC.language', str_replace( '_', '-', get_locale() ) );
			self::tag( 'DC.publisher', $name );
			if ( $c['post'] instanceof WP_Post ) {
				self::tag( 'DC.date', get_post_modified_time( 'c', true, $c['post'] ) );
				self::tag( 'DC.type', 'Text' );
			}
			if ( $c['keywords'] ) {
				self::tag( 'DC.subject', implode( ', ', $c['keywords'] ) );
			}
		}
	}

	private static function verification() {
		$map = array(
			'v_google'    => 'google-site-verification',
			'v_bing'      => 'msvalidate.01',
			'v_yandex'    => 'yandex-verification',
			'v_baidu'     => 'baidu-site-verification',
			'v_pinterest' => 'p:domain_verify',
			'v_facebook'  => 'facebook-domain-verification',
		);
		foreach ( $map as $opt => $name ) {
			self::tag( $name, trim( (string) sxseo_opt( $opt ) ) );
		}
	}

	private static function social( array $c ) {
		$s     = SXSEO_Settings::all();
		$title = $c['og_title'] ?: $c['title'];
		$desc  = $c['og_desc'] ?: $c['desc'];
		self::tag( 'og:locale', get_locale(), 'property' );
		self::tag( 'og:type', 'home' === $c['type'] || 'front' === $c['type'] ? 'website' : $c['og_type'], 'property' );
		self::tag( 'og:title', $title, 'property' );
		self::tag( 'og:description', $desc, 'property' );
		self::tag( 'og:url', $c['url'], 'property' );
		self::tag( 'og:site_name', get_bloginfo( 'name' ), 'property' );
		if ( $s['fb_app_id'] ) {
			self::tag( 'fb:app_id', $s['fb_app_id'], 'property' );
		}
		if ( $c['image'] ) {
			self::tag( 'og:image', $c['image'], 'property' );
			if ( 0 === strpos( $c['image'], 'https://' ) ) {
				self::tag( 'og:image:secure_url', $c['image'], 'property' );
			}
			$att = attachment_url_to_postid( $c['image'] );
			if ( $att ) {
				$meta = wp_get_attachment_metadata( $att );
				if ( ! empty( $meta['width'] ) ) {
					self::tag( 'og:image:width', (string) $meta['width'], 'property' );
					self::tag( 'og:image:height', (string) $meta['height'], 'property' );
				}
				$alt = get_post_meta( $att, '_wp_attachment_image_alt', true );
				self::tag( 'og:image:alt', $alt ?: $title, 'property' );
				$mime = get_post_mime_type( $att );
				self::tag( 'og:image:type', (string) $mime, 'property' );
			}
		}
		if ( 'article' === $c['og_type'] && $c['post'] instanceof WP_Post ) {
			self::tag( 'article:published_time', get_post_time( 'c', true, $c['post'] ), 'property' );
			self::tag( 'article:modified_time', get_post_modified_time( 'c', true, $c['post'] ), 'property' );
			self::tag( 'article:author', get_the_author_meta( 'display_name', $c['post']->post_author ), 'property' );
			if ( ! empty( $c['ctx']['terms']['primary'] ) ) {
				self::tag( 'article:section', $c['ctx']['terms']['primary'], 'property' );
			}
			foreach ( (array) get_the_tags( $c['post'] ) as $t ) {
				if ( $t instanceof WP_Term ) {
					self::tag( 'article:tag', $t->name, 'property' );
				}
			}
		}
		if ( 'none' !== $s['twitter_card'] ) {
			self::tag( 'twitter:card', $c['image'] ? $s['twitter_card'] : 'summary' );
			self::tag( 'twitter:title', $title );
			self::tag( 'twitter:description', $desc );
			if ( $c['image'] ) {
				self::tag( 'twitter:image', $c['image'] );
			}
			if ( $s['twitter_site'] ) {
				$h = '@' . ltrim( $s['twitter_site'], '@' );
				self::tag( 'twitter:site', $h );
				self::tag( 'twitter:creator', $h );
			}
		}
	}
}