<?php
/**
 * REST API endpoint for AI Search settings.
 *
 * Exposes plugin configuration as JSON for debugging purposes.
 *
 * @package AI_Search
 * @since 1.18.0
 */

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

class AI_Search_REST_API {

	/**
	 * REST API namespace.
	 */
	const NAMESPACE = 'ai-search/v1';

	/**
	 * Register hooks.
	 */
	public function __construct() {
		add_action( 'rest_api_init', [ $this, 'register_routes' ] );
	}

	/**
	 * Register REST API routes.
	 */
	public function register_routes() {
		register_rest_route( self::NAMESPACE, '/settings', [
			'methods'             => 'GET',
			'callback'            => [ $this, 'get_settings' ],
			'permission_callback' => '__return_true',
		] );
	}

	/**
	 * Get all plugin settings.
	 *
	 * @return WP_REST_Response
	 */
	public function get_settings() {
		global $wpdb;

		$provider = get_option( 'ai_search_provider', 'ai_service' );

		// Count posts with embeddings
		$embedding_count = (int) $wpdb->get_var(
			"SELECT COUNT(*) FROM {$wpdb->postmeta} WHERE meta_key = '_ai_search_embedding'"
		);

		// Get public post types
		$post_types = get_post_types( [ 'public' => true ], 'names' );
		unset( $post_types['attachment'] );

		// Get custom fields per post type
		$custom_fields = [];
		foreach ( $post_types as $post_type ) {
			$fields = get_option( 'ai_search_custom_fields_' . $post_type, [] );
			if ( ! empty( $fields ) ) {
				$custom_fields[ $post_type ] = $fields;
			}
		}

		$settings = [
			'plugin_version'       => AI_SEARCH_VERSION,
			'wordpress_version'    => get_bloginfo( 'version' ),
			'php_version'          => phpversion(),
			'woocommerce_active'   => class_exists( 'WooCommerce' ),
			'provider'             => $provider,
			'has_api_key'          => ! empty( get_option( 'ai_search_api_key', '' ) ),
			'has_service_token'    => ! empty( get_option( 'ai_search_service_token', '' ) ),
			'openai_model'         => get_option( 'ai_search_openai_model', 'text-embedding-3-small' ),
			'similarity_threshold' => (float) get_option( 'ai_search_similarity_threshold', 0.30 ),
			'badge_public'         => (bool) get_option( 'ai_search_badge_public', false ),
			'setup_completed'      => (bool) get_option( 'ai_search_setup_completed', false ),
			'woocommerce_fields'   => get_option( 'ai_search_woocommerce_fields', [] ),
			'custom_fields'        => $custom_fields,
			'total_embeddings'     => $embedding_count,
			'post_types'           => array_values( $post_types ),
		];

		return rest_ensure_response( $settings );
	}
}