public ResponseEntity pay()

in src/api-server/src/main/java/com/google/abmedge/apiserver/ApiServerController.java [201:254]
54 lines of code
8 McCabe index (conditional complexity)

  public ResponseEntity<String> pay(@RequestBody PayRequest payRequest) {
    BigDecimal totalCost = new BigDecimal(0);
    String responseStr;
    List<PurchaseItem> requestedItemList = payRequest.getItems();
    List<PurchaseItem> purchaseItems = new ArrayList<>();
    List<PaymentUnit> payUnits = new ArrayList<>();
    if (requestedItemList.isEmpty()) {
      return new ResponseEntity<>("", HttpStatus.OK);
    }
    Map<String, Long> itemIdsToCountMap =
        requestedItemList.stream()
            .collect(Collectors.toMap(pi -> pi.getItemId().toString(), PurchaseItem::getItemCount));
    try {
      Optional<List<Item>> optionalItemList = getItemDetails(itemIdsToCountMap);
      if (optionalItemList.isEmpty()) {
        return new ResponseEntity<>(
            "Failed to fetch items details", HttpStatus.INTERNAL_SERVER_ERROR);
      }
      List<Item> itemList = optionalItemList.get();
      int totalItemsRetrieved = itemList.size();
      int totalItemsRequested = itemIdsToCountMap.size();
      if (totalItemsRetrieved != totalItemsRequested) {
        LOGGER.warn(
            String.format(
                "There is a mismatch between number of items requested and retrieved - %s/%s",
                totalItemsRetrieved, totalItemsRequested));
      }
      for (Item item : itemList) {
        UUID id = item.getId();
        BigDecimal itemCount = new BigDecimal(itemIdsToCountMap.get(id.toString()));
        BigDecimal totalItemCost = item.getPrice().multiply(itemCount);
        totalCost = totalCost.add(totalItemCost);
        PurchaseItem purchaseItem = new PurchaseItem(id, itemIdsToCountMap.get(id.toString()));
        PaymentUnit paymentUnit = new PaymentUnit(id, item.getName(), itemCount, totalItemCost);
        purchaseItems.add(purchaseItem);
        payUnits.add(paymentUnit);
      }
      boolean updatedItemDetails = updateItemDetails(purchaseItems);
      if (!updatedItemDetails) {
        return new ResponseEntity<>(
            "Failed to update purchased item information", HttpStatus.INTERNAL_SERVER_ERROR);
      }
      Optional<String> optionalBill =
          makePayment(payRequest.getType(), payRequest.getPaidAmount(), totalCost, payUnits);
      if (optionalBill.isEmpty()) {
        return new ResponseEntity<>(
            "Failed to process payment for the order", HttpStatus.INTERNAL_SERVER_ERROR);
      }
      responseStr = optionalBill.get();
    } catch (IOException | InterruptedException e) {
      return new ResponseEntity<>("FAILED", HttpStatus.INTERNAL_SERVER_ERROR);
    }
    return new ResponseEntity<>(responseStr, HttpStatus.OK);
  }