<?php
/**
 * POST /storebridge/v1/products/{id}/status: sync result pushed by Storebridge Cloud.
 *
 * @package Storebridge
 */

declare( strict_types=1 );

namespace Storebridge\Inbound;

defined( 'ABSPATH' ) || exit;

use Storebridge\Contract\ProductSyncStatus;
use Storebridge\Sync\ProductMeta;
use WP_Error;
use WP_REST_Request;
use WP_REST_Response;

/**
 * Stores the TikTok status, ids and errors of a product as product meta.
 */
final class ProductStatusController {

	public const NAMESPACE = 'storebridge/v1';

	/**
	 * Constructor.
	 *
	 * @param RequestVerifier $verifier Signature verifier.
	 */
	public function __construct( private readonly RequestVerifier $verifier ) {}

	/**
	 * Register the route (on rest_api_init).
	 */
	public function register_routes(): void {
		register_rest_route(
			self::NAMESPACE,
			'/products/(?P<woo_product_id>\d+)/status',
			array(
				'methods'             => 'POST',
				'callback'            => array( $this, 'handle' ),
				'permission_callback' => array( $this->verifier, 'verify' ),
			)
		);
	}

	/**
	 * Store the status.
	 *
	 * @param WP_REST_Request $request Signed request from the cloud.
	 * @return WP_REST_Response|WP_Error
	 */
	public function handle( WP_REST_Request $request ) {
		// get_param() prefers the JSON body over the URL; the id must come from the signed path.
		$product_id = (int) ( $request->get_url_params()['woo_product_id'] ?? 0 );
		$data       = json_decode( $request->get_body(), true );
		try {
			$status = ProductSyncStatus::from_array( is_array( $data ) ? $data : array() );
		} catch ( \Throwable $e ) {
			return new WP_Error( 'storebridge_invalid_body', 'The product status is invalid.', array( 'status' => 400 ) );
		}
		if ( $status->woo_product_id !== $product_id ) {
			return new WP_Error( 'storebridge_invalid_body', 'The product id in the body does not match the URL.', array( 'status' => 400 ) );
		}
		if ( 'product' !== get_post_type( $product_id ) ) {
			return new WP_Error( 'storebridge_not_found', 'Unknown product.', array( 'status' => 404 ) );
		}

		$stored_at = (string) get_post_meta( $product_id, ProductMeta::STATUS_AT, true );
		if ( null !== $status->occurred_at && '' !== $stored_at && strtotime( $stored_at ) > strtotime( $status->occurred_at ) ) {
			return new WP_REST_Response( null, 204 );
		}

		update_post_meta( $product_id, ProductMeta::STATUS, $status->sync_state->value );
		$this->set_or_delete( $product_id, ProductMeta::TIKTOK_STATUS, $status->tiktok_status );
		$this->set_or_delete( $product_id, ProductMeta::PRODUCT_ID, $status->tiktok_product_id );
		$this->set_or_delete( $product_id, ProductMeta::SYNCED_AT, $status->last_synced_at );
		$this->set_or_delete( $product_id, ProductMeta::STATUS_AT, $status->occurred_at );

		$errors = array_map( static fn ( $error ) => $error->to_array(), $status->errors );
		if ( array() === $errors && null !== $status->last_error ) {
			$errors = array( $status->last_error->to_array() );
		}
		$this->set_or_delete( $product_id, ProductMeta::ERRORS, array() === $errors ? null : (string) wp_json_encode( $errors ) );

		foreach ( $status->skus as $sku ) {
			$target = 0 === $sku->woo_variation_id ? $product_id : $sku->woo_variation_id;
			if ( $target === $product_id || wp_get_post_parent_id( $target ) === $product_id ) {
				update_post_meta( $target, ProductMeta::SKU_ID, $sku->tiktok_sku_id );
			}
		}

		return new WP_REST_Response( null, 204 );
	}

	/**
	 * Update a meta value, or delete it when null.
	 *
	 * @param int         $product_id Product id.
	 * @param string      $key        Meta key.
	 * @param string|null $value      Value.
	 */
	private function set_or_delete( int $product_id, string $key, ?string $value ): void {
		if ( null === $value ) {
			delete_post_meta( $product_id, $key );
			return;
		}
		update_post_meta( $product_id, $key, $value );
	}
}