<?php

declare( strict_types=1 );

namespace AcezSeo\Support;

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

/**
 * Detects other active SEO plugins so Acez SEO can avoid printing duplicate meta tags.
 */
final class SeoPluginDetector
{
	private const KNOWN_PLUGINS = array(
		'Yoast SEO'      => 'WPSEO_VERSION',
		'Rank Math'      => 'RANK_MATH_VERSION',
		'All in One SEO' => 'AIOSEO_VERSION',
		'SEOPress'       => 'SEOPRESS_VERSION',
		'Slim SEO'       => 'SLIM_SEO_VERSION',
	);

	public static function detect(): ?string
	{
		foreach ( self::known_plugins() as $name => $constant )
		{
			if ( defined( $constant ) )
			{
				return $name;
			}
		}

		return null;
	}

	public static function has_conflict(): bool
	{
		return null !== self::detect();
	}

	/**
	 * @return array<string, string>
	 */
	private static function known_plugins(): array
	{
		/**
		 * Filters the list of "plugin name => defined constant" pairs used to detect
		 * other active SEO plugins that would conflict with Acez SEO's own output.
		 *
		 * @param array<string, string> $known_plugins
		 */
		return (array) apply_filters( 'acez_seo_known_seo_plugins', self::KNOWN_PLUGINS );
	}
}