<?php

namespace Aikanen\Modules\CategoryImport;

defined('ABSPATH') || exit;

class CategoryImportMapper
{
   const META_AIKANEN_ID = '_aikanen_group_id';

   public function upsert(array $group): string
   {
      $aikanenId = (string) ($group['id'] ?? '');
      $name = $group['name'] ?? '';
      $description = $group['description'] ?? '';
      $isPrivate = $group['is_private'] ?? false;
      $isUnavailable = $group['is_unavailable'] ?? false;

      if ($aikanenId === '' || !$name) {
         return 'skipped';
      }

      $existing = $this->findCategoryByAikanenId($aikanenId);

      if ($existing) {
         $termId = $existing;
         wp_update_term($termId, 'product_cat', [
            'name' => $name,
            'description' => $description ?? '',
         ]);

         return 'updated';
      }

      $result = wp_insert_term($name, 'product_cat', [
         'description' => $description ?? '',
      ]);

      if (is_wp_error($result)) {
         // Term with this name may already exist - try to claim it if unlinked
         if ($result->get_error_code() === 'term_exists') {
            $termId = (int) $result->get_error_data();
            $linked = get_term_meta($termId, self::META_AIKANEN_ID, true);

            if (!$linked) { // Unlinked term - claim it
               update_term_meta($termId, self::META_AIKANEN_ID, $aikanenId);
               return 'linked';
            }
         }

         return 'skipped';
      }

      $termId = (int) $result['term_id'];
      update_term_meta($termId, self::META_AIKANEN_ID, $aikanenId);

      return 'created';
   }

   // Assign product to categories
   private function syncCategories(array $service): void
   {
      $groups = $service['serviceGroups'] ?? [];
      $productId = $this->productMapper->findProductByAikanenId((string) ($service['id'] ?? ''));

      if (!$productId || empty($groups)) {
         return;
      }

      $termIds = [];
      foreach ($groups as $group) {
         $groupId = (string) ($group['id'] ?? '');
         if ($groupId === '') continue;

         $termId = $this->categoryMapper->findCategoryByAikanenId($groupId);
         if ($termId) {
            $termIds[] = $termId;
         }
      }

      if (!empty($termIds)) {
         wp_set_object_terms($productId, $termIds, 'product_cat', true);
      }
   }

   // Find category matching service group ID from Aikanen (if exists)
   public function findCategoryByAikanenId(string $aikanenId): ?int
   {
      $terms = get_terms([
         'taxonomy' => 'product_cat',
         'hide_empty' => false,
         'meta_query' => [
            [
               'key' => self::META_AIKANEN_ID,
               'value' => $aikanenId,
            ],
         ],
         'fields' => 'ids',
         'number' => 1,
      ]);

      if (is_wp_error($terms) || empty($terms)) {
         return null;
      }

      return (int) $terms[0];
   } 
}