<?php
if ( ! defined( 'ABSPATH' ) ) exit;

/**
 * Detects other plugins that manage schema / robots / llms.txt so we can
 * "play nice" by default and avoid duplicate structured data.
 */
class Semantic_Compat {

    /**
     * @return array<string,string> slug => display name of active SEO/schema plugins
     */
    public static function detect_seo_plugins() {
        $found = [];
        if ( defined( 'WPSEO_VERSION' ) )                       $found['yoast']     = 'Yoast SEO';
        if ( class_exists( 'RankMath' ) )                        $found['rankmath']  = 'Rank Math';
        if ( defined( 'AIOSEO_VERSION' ) || function_exists( 'aioseo' ) ) $found['aioseo'] = 'All in One SEO';
        if ( defined( 'SEOPRESS_VERSION' ) )                     $found['seopress']  = 'SEOPress';
        if ( class_exists( 'The_SEO_Framework\\Load' ) || function_exists( 'the_seo_framework' ) ) $found['tsf'] = 'The SEO Framework';
        if ( defined( 'SCHEMA_PRO_VERSION' ) || class_exists( 'Schema_Pro' ) ) $found['schemapro'] = 'Schema Pro';
        return $found;
    }

    public static function seo_plugin_active() {
        return ! empty( self::detect_seo_plugins() );
    }

    /**
     * Should we emit the WebPage + BreadcrumbList nodes?
     * In 'auto' mode we defer these to an active SEO plugin (which already emits them)
     * and only output our unique value (entity about[] + FAQPage).
     */
    public static function should_emit_page_schema() {
        $mode = Semantic_Settings::schema_compat_mode(); // auto | full
        if ( $mode === 'full' ) return true;
        return ! self::seo_plugin_active();
    }

    /**
     * Detect whether another plugin already serves /llms.txt, either as a
     * physical file or by a known AI/SEO plugin that registers the route.
     */
    public static function llms_txt_owned_elsewhere() {
        // Physical file on disk takes precedence over any rewrite rule
        if ( file_exists( ABSPATH . 'llms.txt' ) ) return 'file';
        // Known plugins that also output llms.txt
        if ( defined( 'RANKMATH_VERSION' ) && class_exists( 'RankMath\\Llms_Txt' ) ) return 'Rank Math';
        return false;
    }
}