<?php

//------------------------------------------
// Function: Transform Catalog to Meta Feed
//------------------------------------------
function catalogToMetaFeed($catalog, $config) {
  $meta_feed = [];
  
  foreach ($catalog as $product) {
    // Extract product data
    $product_id = $product['productcode'] ?? '';
    $product_name = $product['productname'] ?? '';
    $original_description = cleanText($product['productdescription'] ?? '');
    
    // Get meta description based on product code (with fallback to original)
    $description = getMetaDescription($product_id, $original_description);
    
    $base_price = floatval($product['price'] ?? 0);
    $url_slug = $product['url_slug'] ?? '';
    $main_image = buildImageUrl($product['full_path'] ?? '', $config['image_base_url']);
    $product_url = buildProductUrl($url_slug, $config['base_url']);
    
    // Check if product has variants
    $has_variants = !empty($product['configurations']);
    
    if (!$has_variants) {
      // Simple product - no variants
      $meta_feed[] = buildMetaProduct([
        'id' => $product_id,
        'title' => $product_name,
        'description' => $description,
        'price' => $base_price,
        'link' => $product_url,
        'image_link' => $main_image,
      ], $config);
      
    } else {
      // Product with variants
      $variants = extractVariants($product, $base_price);
      
      foreach ($variants as $variant) {
        // Combine meta description with variant suffix
        $variant_description = $description . ' ' . $variant['description_suffix'];
        
        $meta_feed[] = buildMetaProduct([
          'id' => $variant['id'],
          'item_group_id' => $product_id,
          'title' => $variant['title'],
          'description' => $variant_description,
          'price' => $variant['price'],
          'link' => $product_url,
          'image_link' => $variant['image'],
          'additional_image_link' => $variant['additional_image'] ?? '',
        ], $config);
      }
    }
  }
  
  return $meta_feed;
}

//------------------------------------------
// Extract variants from configurations
//------------------------------------------
function extractVariants($product, $base_price) {
  $variants = [];
  $product_id = $product['productcode'];
  $product_name = $product['productname'];
  $image_base_url = $GLOBALS['meta_config']['image_base_url'];
  
  $configurations = $product['configurations'] ?? [];
  
  foreach ($configurations as $config) {
    if ($config['type'] === 'group') {
      $group_name = $config['assignment_name'] ?? 'Option';
      $attributes = $config['attributes'] ?? [];
      
      foreach ($attributes as $attr) {
        // Calculate price
        $attr_price = floatval($attr['price'] ?? 0);
        $attr_modifier = intval($attr['price_modifier'] ?? 1);
        $final_price = calculateVariantPrice($base_price, $attr_price, $attr_modifier);
        
        // Get images (using image_base_url for images)
        $variant_image = buildImageUrl($attr['alternative_media_full_path'] ?? '', $image_base_url);
        $additional_image = buildImageUrl($attr['full_path'] ?? '', $image_base_url);
        
        // Fallback to main product image if no variant image
        if (empty($variant_image)) {
          $variant_image = buildImageUrl($product['full_path'] ?? '', $image_base_url);
        }
        
        // Extract option name from item_name
        $item_name = $attr['item_name'] ?? '';
        $option_name = formatAttributeName($item_name);
        
        // Build variant
        $variants[] = [
          'id' => $product_id . '_' . ($attr['attribute_id'] ?? ''),
          'title' => $product_name . ' - ' . $option_name,
          'description_suffix' => 'Available with ' . $option_name . ' ' . strtolower($group_name) . '.',
          'price' => $final_price,
          'image' => $variant_image,
          'additional_image' => $additional_image,
        ];
      }
    }
  }
  
  return $variants;
}

//------------------------------------------
// Build Meta product row
//------------------------------------------
function buildMetaProduct($data, $config) {
  $product = [
    'id' => $data['id'],
    'title' => $data['title'],
    'description' => $data['description'],
    'availability' => $config['availability'],
    'condition' => $config['condition'],
    'price' => formatPrice($data['price'], $config['currency']),
    'link' => $data['link'],
    'image_link' => $data['image_link'],
    'brand' => $config['brand'],
    'google_product_category' => $config['google_product_category'],
  ];
  
  // Add optional fields if present
  if (!empty($data['item_group_id'])) {
    $product['item_group_id'] = $data['item_group_id'];
  }
  
  if (!empty($data['additional_image_link'])) {
    $product['additional_image_link'] = $data['additional_image_link'];
  }
  
  return $product;
}

//------------------------------------------
// Helper Functions
//------------------------------------------
function getMetaDescription($product_code, $fallback_description = '') {
  global $meta_descriptions;
  
  // First check for exact match
  if (isset($meta_descriptions[$product_code])) {
    return $meta_descriptions[$product_code];
  }
  
  // Then check for pattern match (starts with)
  foreach ($meta_descriptions as $pattern => $description) {
    if (strpos($product_code, $pattern) === 0) {
      return $description;
    }
  }
  
  // Return fallback if no match
  return $fallback_description;
}

function calculateVariantPrice($base_price, $modifier_price, $modifier_type) {
  if ($modifier_price <= 0) {
    return $base_price;
  }
  
  switch ($modifier_type) {
    case 1: // Addition
      return $base_price + $modifier_price;
    case 2: // Multiplication
      return $base_price * $modifier_price;
    default:
      return $base_price;
  }
}

function buildImageUrl($path, $base_url) {
  if (empty($path)) return '';
  return rtrim($base_url, '/') . '/' . ltrim($path, '/');
}

function buildProductUrl($slug, $base_url) {
  if (empty($slug)) return '';
  return rtrim($base_url, '/') . '/product/' . $slug;
}

function formatPrice($price, $currency) {
  return number_format($price, 2, '.', '') . ' ' . $currency;
}

function cleanText($text) {
  $text = strip_tags($text);
  $text = preg_replace('/\s+/', ' ', $text);
  return trim($text);
}

function formatAttributeName($name) {
  // Remove prefix like "bracelet_"
  $name = preg_replace('/^bracelet_/', '', $name);
  // Replace underscores with spaces
  $name = str_replace('_', ' ', $name);
  // Capitalize words
  return ucwords($name);
}

//------------------------------------------
// Output Functions
//------------------------------------------
function outputMetaFeedCSV($meta_feed) {
  header('Content-Type: text/csv; charset=utf-8');
  header('Content-Disposition: attachment; filename="meta_product_feed.csv"');
  
  $output = fopen('php://output', 'w');
  
  // Write headers
  if (!empty($meta_feed)) {
    fputcsv($output, array_keys($meta_feed[0]));
    
    // Write data
    foreach ($meta_feed as $row) {
      fputcsv($output, $row);
    }
  }
  
  fclose($output);
}

function outputMetaFeedXML($meta_feed) {
  header('Content-Type: application/xml; charset=utf-8');
  
  $xml = new SimpleXMLElement('<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:g="http://base.google.com/ns/1.0"></rss>');
  $channel = $xml->addChild('channel');
  $channel->addChild('title', 'Morval Product Feed');
  $channel->addChild('link', $GLOBALS['meta_config']['base_url']);
  $channel->addChild('description', 'Product feed for Meta catalog');
  
  foreach ($meta_feed as $product) {
    $item = $channel->addChild('item');
    
    foreach ($product as $key => $value) {
      $xml_key = 'g:' . $key;
      $item->addChild($xml_key, htmlspecialchars($value));
    }
  }
  
  echo $xml->asXML();
}

function outputMetaFeedJSON($meta_feed) {
  //header('Content-Type: application/json; charset=utf-8');
  echo json_encode($meta_feed, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
}

?>