<?php

namespace Akantio\Woo\Rest;

use Akantio\Woo\Stock\StockSyncBuilder;
use Akantio\Woo\Stock\StockSyncPayload;
use Akantio\Woo\Stock\StockSyncRepository;
use Akantio\Woo\Support\ActivityLog;
use InvalidArgumentException;
use RuntimeException;
use WP_Error;
use WP_REST_Request;
use WP_REST_Response;

defined( 'ABSPATH' ) || exit;

/**
 * POST /stock-sync — applies a POS order's stock deltas to WooCommerce
 * exactly once. Companion to OrderController but for "Stock-only Sync" mode
 * (see WooPosSyncOrderStockLevelsService on the akantio_pos side), which
 * never creates a WooCommerce order — see StockSyncBuilder for how
 * idempotency is tracked without one.
 *
 * Authenticated the same way OrderController is — see Rest/NativeAuth.php.
 */
class StockSyncController {

	private const NAMESPACE = 'akantio-pos/v1';

	private StockSyncBuilder $builder;
	private StockSyncRepository $repository;
	private ActivityLog $activityLog;

	public function __construct( StockSyncBuilder $builder, StockSyncRepository $repository, ActivityLog $activityLog ) {
		$this->builder     = $builder;
		$this->repository  = $repository;
		$this->activityLog = $activityLog;
	}

	public function registerRoutes(): void {
		register_rest_route( self::NAMESPACE, '/stock-sync', [
			'methods'             => 'POST',
			'callback'            => [ $this, 'create' ],
			'permission_callback' => [ $this, 'authorize' ],
		] );

		register_rest_route( self::NAMESPACE, '/stock-sync', [
			'methods'             => 'GET',
			'callback'            => [ $this, 'lookup' ],
			'permission_callback' => [ $this, 'authorize' ],
			'args'                => [
				'pos_order_id' => [ 'required' => true ],
			],
		] );
	}

	public function authorize(): bool {
		return current_user_can( 'manage_woocommerce' );
	}

	/**
	 * GET /stock-sync?pos_order_id=X — lets akantio_pos check whether this
	 * POS order's stock delta was already applied before attempting to push
	 * it again, so a broken local sync record doesn't double-decrement
	 * WooCommerce's stock (POST is idempotent by itself too, see
	 * StockSyncBuilder::build(), but this lets the caller skip the push
	 * entirely and just reconcile its own state).
	 */
	public function lookup( WP_REST_Request $request ) {
		$posOrderId = (string) $request->get_param( 'pos_order_id' );

		if ( '' === $posOrderId ) {
			return new WP_Error( 'akantio_woo_missing_pos_order_id', 'pos_order_id is required.', [ 'status' => 400 ] );
		}

		$existing = $this->repository->findByPosOrderId( $posOrderId );

		if ( null === $existing ) {
			return new WP_Error( 'akantio_woo_stock_sync_not_found', 'No stock sync found for this pos_order_id.', [ 'status' => 404 ] );
		}

		return new WP_REST_Response( [
			'pos_order_id' => $posOrderId,
			'synced_at'    => $existing['synced_at'],
		], 200 );
	}

	public function create( WP_REST_Request $request ) {
		$data = $request->get_json_params();

		if ( ! is_array( $data ) ) {
			return new WP_Error( 'akantio_woo_invalid_body', 'Request body must be a JSON object.', [ 'status' => 400 ] );
		}

		try {
			$payload = StockSyncPayload::fromArray( $data );
		} catch ( InvalidArgumentException $e ) {
			return new WP_Error( 'akantio_woo_invalid_payload', $e->getMessage(), [ 'status' => 400 ] );
		}

		try {
			$result = $this->builder->build( $payload );
		} catch ( RuntimeException $e ) {
			return new WP_Error( 'akantio_woo_stock_sync_failed', $e->getMessage(), [ 'status' => 500 ] );
		}

		if ( $result['applied'] ) {
			$this->activityLog->record( 'stock_synced', [
				'pos_order_id' => $payload->posOrderId(),
				'product_ids'  => array_column( $payload->productUpdates(), 'product_id' ),
			] );
		}

		return new WP_REST_Response( $result, $result['applied'] ? 201 : 200 );
	}
}