<?php
/**
 * SEO plugin conflict detector and suppressor.
 *
 * Detects active third-party SEO plugins (Yoast SEO, RankMath, AIOSEO)
 * that generate their own Product schema and suppresses their output
 * to prevent duplicate/conflicting structured data.
 *
 * @package AICommerce\Schema
 */

declare(strict_types=1);

namespace AICommerce\Schema;

/**
 * Detects and suppresses duplicate schema from SEO plugins.
 */
class ConflictDetector {

	/**
	 * Known SEO plugins and the hooks/filters they use for schema output.
	 *
	 * @var array<string, array<string, mixed>>
	 */
	private const KNOWN_PLUGINS = array(
		'yoast'    => array(
			'detection_class'  => 'WPSEO_Schema',
			'detection_filter' => 'wpseo_schema_graph',
			'label'            => 'Yoast SEO',
		),
		'rankmath' => array(
			'detection_class'  => 'RankMath\\JsonLD',
			'detection_filter' => 'rank_math/json_ld',
			'label'            => 'Rank Math',
		),
		'aioseo'   => array(
			'detection_class'  => 'AIOSEO\\Plugin\\Schema\\Schema',
			'detection_filter' => 'aioseo_schema_output',
			'label'            => 'All in One SEO',
		),
	);

	/**
	 * Detected active SEO plugins.
	 *
	 * @var array<string, string> Plugin key => label.
	 */
	private array $detected = array();

	/**
	 * Detect which SEO plugins are active.
	 *
	 * Should be called early (e.g., on plugins_loaded or init) before
	 * the suppression hooks are registered.
	 *
	 * @return array<string, string> Detected plugin key => label pairs.
	 */
	public function detect(): array {
		$this->detected = array();

		foreach ( self::KNOWN_PLUGINS as $key => $config ) {
			if ( class_exists( $config['detection_class'] ) ) {
				$this->detected[ $key ] = $config['label'];
			}
		}

		/**
		 * Filters the detected SEO plugins.
		 *
		 * Third-party integrations can add their own detected plugins.
		 *
		 * @param array<string, string> $detected Plugin key => label pairs.
		 */
		$this->detected = apply_filters( 'aicommerce_detected_seo_plugins', $this->detected );

		return $this->detected;
	}

	/**
	 * Suppress schema output from detected SEO plugins.
	 *
	 * Only suppresses Product-related schema — leaves general website/organization
	 * schema from SEO plugins intact when possible.
	 *
	 * @return void
	 */
	public function suppress(): void {
		$should_suppress = get_option( 'aicommerce_conflict_suppress', true );

		if ( ! $should_suppress ) {
			return;
		}

		if ( empty( $this->detected ) ) {
			$this->detect();
		}

		foreach ( $this->detected as $key => $label ) {
			$method = "suppress_{$key}";
			if ( method_exists( $this, $method ) ) {
				$this->{$method}();
			}
		}
	}

	/**
	 * Suppress Yoast SEO Product schema.
	 *
	 * Removes the Product piece from Yoast's schema graph while preserving
	 * WebSite, Organization, and other pieces.
	 *
	 * @return void
	 */
	private function suppress_yoast(): void {
		add_filter(
			'wpseo_schema_graph_pieces',
			static function ( array $pieces ): array {
				if ( ! is_product() ) {
					return $pieces;
				}

				return array_filter(
					$pieces,
					static function ( $piece ): bool {
						$class_name = get_class( $piece );
						// Remove Yoast's Product and Offer schema pieces.
						return ! str_contains( $class_name, 'Product' )
							&& ! str_contains( $class_name, 'Offer' );
					}
				);
			},
			100
		);
	}

	/**
	 * Suppress Rank Math Product schema.
	 *
	 * @return void
	 */
	private function suppress_rankmath(): void {
		add_filter(
			'rank_math/json_ld',
			static function ( array $data ): array {
				if ( ! is_product() ) {
					return $data;
				}

				// Remove Product-type entries from RankMath's JSON-LD.
				foreach ( $data as $key => $entry ) {
					if (
						isset( $entry['@type'] ) &&
						(
							'Product' === $entry['@type'] ||
							( is_array( $entry['@type'] ) && in_array( 'Product', $entry['@type'], true ) )
						)
					) {
						unset( $data[ $key ] );
					}
				}

				return $data;
			},
			100
		);
	}

	/**
	 * Suppress All in One SEO Product schema.
	 *
	 * @return void
	 */
	private function suppress_aioseo(): void {
		add_filter(
			'aioseo_schema_output',
			static function ( array $graphs ): array {
				if ( ! is_product() ) {
					return $graphs;
				}

				return array_filter(
					$graphs,
					static function ( array $graph ): bool {
						return ! isset( $graph['@type'] ) || 'Product' !== $graph['@type'];
					}
				);
			},
			100
		);
	}

	/**
	 * Get list of detected SEO plugins.
	 *
	 * @return array<string, string> Plugin key => label pairs.
	 */
	public function get_detected(): array {
		if ( empty( $this->detected ) ) {
			$this->detect();
		}

		return $this->detected;
	}

	/**
	 * Check if any conflicting SEO plugins are detected.
	 *
	 * @return bool
	 */
	public function has_conflicts(): bool {
		if ( empty( $this->detected ) ) {
			$this->detect();
		}

		return ! empty( $this->detected );
	}
}