<?php

namespace Aikanen\Modules\ProductImport;

defined('ABSPATH') || exit;

// Map Aikanen product data to WooCommerce product data
class ProductImportMapper
{
   const META_AIKANEN_ID = '_aikanen_service_id';

   const OPTION_VAT_MAP = 'aikanen_vat_map';

   const DEFAULT_VAT_MAP = [
      '1' => '', // Standard
      '2' => 'reduced-rate',
      '3' => 'reduced-rate',
      '4' => 'zero-rate',
   ];

   const VAT_LABELS = [
      '1' => 'Standard',
      '2' => 'Reduced',
      '3' => 'Reduced',
      '4' => 'Zero VAT',
   ];

   private string $assetBaseUrl = AIKANEN_S3_ASSET_URL;

   // Save/update imported product at WooCommerce
   public function upsert(array $service): string
   {
      $aikanenId = (string) ($service['id'] ?? '');
      $name = $service['name'] ?? '';
      $sku = $service['sku'] ?? '';
      $amount = $service['amount'] ?? 0;
      $description = $service['description'] ?? '';
      $shortDescription = $service['short_description'] ?? '';
      $barcode = $service['barcode'] ?? '';
      $stock = $service['stock'] ?? null;
      $unitCost = $service['unit_cost'] ?? null;
      $vatId = $service['vat_id'] ?? null;

      if ($aikanenId === '' || !$name) { // No Aikanen ID or name given - skip
         return 'skipped';
      }

      $price = number_format((int) $amount / 100, 2, '.', '');
      $discounted = $service['discounted'] ?? null;
      $salePrice = $discounted !== null ? number_format((int) $discounted / 100, 2, '.', '') : null;

      // Check if product already exists in WooCommerce
      $existing = get_posts([
         'post_type' => 'product',
         'post_status' => ['any'],
         'meta_key' => self::META_AIKANEN_ID,
         'meta_value' => $aikanenId,
         'numberposts' => 1,
         'fields' => 'ids',
      ]);

      $productId = $existing[0] ?? null;
      $isNew = !$productId;

      if ($isNew) { // New product
         $product = new \WC_Product_Simple();
         $product->update_meta_data(self::META_AIKANEN_ID, $aikanenId);
      } else { // Existing - update
         $product = wc_get_product($productId);

         if (!$product) { // No product found - skip
            return 'skipped';
         }
      }

      $product->set_name($name);
      $product->set_description($description);
      $product->set_short_description($shortDescription);
      $product->set_status('publish');
      $product->set_regular_price($price);
      $product->set_sale_price($salePrice ?? '');
      $product->set_price($salePrice ?? $price);
      $product->set_virtual(false);
      $product->update_meta_data('_aikanen_last_synced', time());

      if (!empty($sku)) { // If has a SKU
         try {
            $product->set_sku($sku);
         } catch (\WC_Data_Exception $e) { // Catch duplicate SKU
            return 'skipped';
         }
      }

      if (!empty($barcode)) { // If has a barcode
         try {
            $product->set_global_unique_id($barcode);
         } catch (\WC_Data_Exception $e) { // Catch duplicate EAN
            return 'skipped';
         }
      }

      if ($stock !== null) { // Enable stock management if data contains stock
         $product->set_manage_stock(true);
         $product->set_stock_quantity((int) $stock);
         $product->set_stock_status((int) $stock > 0 ? 'instock' : 'outofstock');
      } else {
         $product->set_manage_stock(false);
         $product->set_stock_status('instock');
      }

      if (wc_get_container()->get(\Automattic\WooCommerce\Internal\Features\FeaturesController::class)->feature_is_enabled('cost_of_goods_sold')) { // If cost of goods sold is enabled on WooCommerce
         $product->set_cogs_value($unitCost !== null ? round((int) $unitCost / 100, 2) : null);
      }

      // Resolve VAT
      $taxClass = $this->resolveTaxClass((string) $vatId);
      $product->set_tax_status('taxable');
      $product->set_tax_class($taxClass);

      try { // Save product
         $product->save();
      } catch (\WC_Data_Exception $e) {
         return 'skipped';
      }
      
      if ($this->syncImage($product, $this->imageUrl($service))) { // Sync main product image if one was set in Aikanen and product doesn't yet have one in Woo
         $product->save();
      }   

      return $isNew ? 'created' : 'updated';
   }

   // Match tax rate to WooCommerce tax rate
   private function resolveTaxClass(string $vatId): string
   {
      $vatMap = $this->getVatMap();
      return $vatMap[$vatId] ?? '';
   }

   public function getVatMap(): array
   {
      return get_option(self::OPTION_VAT_MAP, self::DEFAULT_VAT_MAP);
   }

   // Build absolute URL for a service image path from Aikanen
   public function imageUrl(array $service): ?string
   {
      $path = $service['image_urls']['original'] ?? null;

      if (!$path || !$this->assetBaseUrl) {
         return null;
      }

      return esc_url_raw(trailingslashit($this->assetBaseUrl) . ltrim($path, '/'));
   }

   // Add image to imported product if one was added to it on Aikanen
   private function syncImage(\WC_Product $product, ?string $url): bool
   {
      if (empty($url) || $product->get_image_id()) { // Nothing to import, or product already has an image
         return false;
      }

      require_once ABSPATH . 'wp-admin/includes/file.php';
      require_once ABSPATH . 'wp-admin/includes/media.php';
      require_once ABSPATH . 'wp-admin/includes/image.php';

      $attachmentId = media_sideload_image($url, $product->get_id(), $product->get_name(), 'id');

      if (is_wp_error($attachmentId)) {
         return false;
      }

      $product->set_image_id($attachmentId);

      return true;
   }   

   // Find product matching service ID from Aikanen (if exists)
   public function findProductByAikanenId(string $serviceId): ?int
   {
      $posts = get_posts([
         'post_type'   => 'product',
         'post_status' => ['any'],
         'meta_key'    => self::META_AIKANEN_ID,
         'meta_value'  => $serviceId,
         'numberposts' => 1,
         'fields'      => 'ids',
      ]);

      return $posts[0] ?? null;
   }    
}