bug fix: PO Lines (#685)

* bug fix: PO Lines

- Correctly display part images for purchase order line items

* Refactor

* Code formatting

lib/api.dart

@@ -118,7 +118,6 @@ class InvenTreeFileService extends FileService {
 
     if (_client != null) {
       _client!.badCertificateCallback = (cert, host, port) {
-        print("BAD CERTIFICATE CALLBACK FOR IMAGE REQUEST");
         return !strictHttps;
       };
     }

lib/inventree/model.dart

@@ -732,6 +732,8 @@ class InvenTreeModel {
 
     var response = await api.get(URL, params: params);
 
+    print("paginated: ${URL}: ${params}");
+
     if (!response.isValid()) {
       return null;
     }

lib/inventree/orders.dart

@@ -114,7 +114,15 @@ class InvenTreeOrderLine extends InvenTreeModel {
 
   String get partName => getString("name", subKey: "part_detail");
 
-  String get partImage => getString("thumbnail", subKey: "part_detail");
+  String get partImage {
+    String img = getString("thumbnail", subKey: "part_detail");
+
+    if (img.isEmpty) {
+      img = getString("image", subKey: "part_detail");
+    }
+
+    return img;
+  }
 
   String get targetDate => getDateString("target_date");
 }

lib/widget/order/po_line_list.dart

@@ -67,7 +67,7 @@ class _PaginatedPOLineListState
     final page = await InvenTreePOLineItem().listPaginated(
       limit,
       offset,
-      filters: params,
+      filters: {...params},
     );
     return page;
   }
@@ -85,7 +85,7 @@ class _PaginatedPOLineListState
           item.progressString,
           color: item.isComplete ? COLOR_SUCCESS : COLOR_WARNING,
         ),
-        leading: InvenTreeAPI().getThumbnail(supplierPart.partImage),
+        leading: InvenTreeAPI().getThumbnail(item.partImage),
         onTap: () async {
           showLoadingOverlay();
           await item.reload();