feat: Affiliate program enrichment (Link Builder, Curated Collections, Smart Links)

includes/Modules/Affiliate/AffiliateTracker.php

@@ -102,9 +102,37 @@ class AffiliateTracker
             'samesite' => 'Lax'
         ];
 
-        // Capture referral code
+        $referral_code = '';
+
+        // 1. Capture from ?ref= parameter
         if (isset($_GET['ref']) && !empty($_GET['ref'])) {
             $referral_code = sanitize_text_field($_GET['ref']);
+        }
+
+        // 2. Or capture from collection slug in URL (e.g., /collection/my-slug)
+        if (empty($referral_code)) {
+            $request_uri = $_SERVER['REQUEST_URI'] ?? '/';
+            $path = parse_url($request_uri, PHP_URL_PATH);
+            
+            // Extract collection slug, accounting for possible subdirectories (e.g. /store/collection/slug)
+            if (preg_match('#/collection/([^/]+)#', $path, $matches)) {
+                $collection_slug = sanitize_text_field($matches[1]);
+                
+                global $wpdb;
+                $collections_table = $wpdb->prefix . 'woonoow_affiliate_collections';
+                $affiliates_table = $wpdb->prefix . 'woonoow_affiliates';
+                
+                $referral_code = $wpdb->get_var($wpdb->prepare("
+                    SELECT a.referral_code 
+                    FROM $collections_table c
+                    JOIN $affiliates_table a ON c.affiliate_id = a.id
+                    WHERE c.slug = %s
+                ", $collection_slug));
+            }
+        }
+
+        // Set the cookie if we found a referral code
+        if (!empty($referral_code)) {
             $result = setcookie(self::COOKIE_NAME, $referral_code, $options);
             $_COOKIE[self::COOKIE_NAME] = $referral_code;
             error_log('[AffiliateTracker] Set woonoow_ref cookie: ' . $referral_code . ', result=' . ($result ? 'true' : 'false'));