bundle parent

bundle.php

<?php

function CUSTOMMODULE_commerce_cart_product_add($order, $product, $quantity, $line_item) {
  if (!empty($product->field_bundled_products)) {
    $ids = array();
    foreach($product->field_bundled_products[LANGUAGE_NONE] as $bundle) {
      $ids[] = $bundle['value'];
    }
    $line_item->data['bundled'] = array();
    $bundles = entity_load('field_collection_item', $ids);
    foreach ($bundles AS $entity) {
      if(!empty($entity->field_single_product)) {
        $product_id = $entity->field_single_product[LANGUAGE_NONE][0]['product_id'];
        $quantity = $entity->field_qty[LANGUAGE_NONE][0]['value'];
        $product = commerce_product_load($product_id);
        $product->commerce_price[LANGUAGE_NONE][0]['amount'] = 0;
        $product->field_cost[LANGUAGE_NONE][0]['amount'] = 0;
        $line = commerce_product_line_item_new($product, $quantity);
        $line->field_bundle_parent[LANGUAGE_NONE][0]['line_item_id '] = $line_item->line_item_id;
        $line->data['bundled'] = array();

        commerce_cart_product_add($order->uid, $line, FALSE);

        $line = entity_metadata_wrapper('commerce_line_item', $line);
        $line->field_bundle_parent->set($line_item->line_item_id);
        $line->save();

        $line_item->data['bundled'][$line->line_item_id->value()] = array(
          'product' => $entity->field_single_product['und'][0]['product_id'],
          'qty' => $entity->field_qty['und'][0]['value'],
        );
      }
    }
    commerce_line_item_save($line_item);
  }
}

function CUSTOMMODULE_commerce_cart_product_remove($order, $product, $quantity, $line_item) {
  if (isset($product->field_bundled_products)) {
    foreach($order->commerce_line_items[LANGUAGE_NONE] AS $item) {
      $line = commerce_line_item_load($item['line_item_id']);
      if ($line->field_bundle_parent[LANGUAGE_NONE][0]['line_item_id'] == $line_item->line_item_id) {
        commerce_cart_order_product_line_item_delete($order, $line->line_item_id, TRUE);
      }
    }
  }
}

function CUSTOMMODULE_form_alter(&$form, &$form_state, $form_id) {
  global $user;
  
  switch($form_id) {
    case 'views_form_commerce_cart_form_CUSTOMMODULE_default': // I used custom view for cart to tweak
      $order = commerce_cart_order_load($user->uid);
      $line_item_ids = array();
      foreach($order->commerce_line_items['und'] as $delta => $item) {
        $line_item_ids[] = $item['line_item_id'];
      }

      $items = commerce_line_item_load_multiple($line_item_ids);
      for($i = 0; $i < count($form['edit_quantity']); $i++) {
        $id = $form['edit_quantity'][$i]['#line_item_id'];
        if(!empty($items[$id]->field_bundle_parent)) {
          $form['edit_quantity'][$i]['#disabled'] = TRUE;
          $form['edit_delete'][$i]['#access'] = FALSE;
        }
      }
      break;
  }
}