private static String renderParameter(ValueParameterDescriptor parameter, boolean named) {
   StringBuilder builder = new StringBuilder();
   if (named) builder.append("[");
   if (parameter.getVarargElementType() != null) {
     builder.append("vararg ");
   }
   builder
       .append(parameter.getName())
       .append(": ")
       .append(
           DescriptorRenderer.SHORT_NAMES_IN_TYPES.renderType(getActualParameterType(parameter)));
   if (DescriptorUtilPackage.hasDefaultValue(parameter)) {
     PsiElement parameterDeclaration = DescriptorToSourceUtils.descriptorToDeclaration(parameter);
     builder.append(" = ").append(getDefaultExpressionString(parameterDeclaration));
   }
   if (named) builder.append("]");
   return builder.toString();
 }
  @Override
  public void updateUI(
      Pair<? extends FunctionDescriptor, ResolutionFacade> itemToShow,
      @NotNull ParameterInfoUIContext context) {
    // todo: when we will have ability to pass Array as vararg, implement such feature here too?
    if (context == null
        || context.getParameterOwner() == null
        || !context.getParameterOwner().isValid()) {
      context.setUIComponentEnabled(false);
      return;
    }

    PsiElement parameterOwner = context.getParameterOwner();
    if (!(parameterOwner instanceof JetValueArgumentList)) {
      context.setUIComponentEnabled(false);
      return;
    }

    JetValueArgumentList argumentList = (JetValueArgumentList) parameterOwner;

    FunctionDescriptor functionDescriptor = itemToShow.first;
    ResolutionFacade resolutionFacade = itemToShow.second;

    List<ValueParameterDescriptor> valueParameters = functionDescriptor.getValueParameters();
    List<JetValueArgument> valueArguments = argumentList.getArguments();

    int currentParameterIndex = context.getCurrentParameterIndex();
    int boldStartOffset = -1;
    int boldEndOffset = -1;
    boolean isGrey = false;
    boolean isDeprecated = KotlinBuiltIns.isDeprecated(functionDescriptor);

    boolean[] usedIndexes = new boolean[valueParameters.size()];
    Arrays.fill(usedIndexes, false);

    boolean namedMode = false;

    if (!isIndexValid(valueParameters, currentParameterIndex)) {
      isGrey = true;
    }

    StringBuilder builder = new StringBuilder();

    PsiElement owner = context.getParameterOwner();
    BindingContext bindingContext =
        resolutionFacade.analyze((JetElement) owner, BodyResolveMode.FULL);

    for (int i = 0; i < valueParameters.size(); ++i) {
      if (i != 0) {
        builder.append(", ");
      }

      boolean highlightParameter =
          i == currentParameterIndex
              || (!namedMode
                  && i < currentParameterIndex
                  && Iterables.getLast(valueParameters).getVarargElementType() != null);

      if (highlightParameter) {
        boldStartOffset = builder.length();
      }

      if (!namedMode) {
        if (valueArguments.size() > i) {
          JetValueArgument argument = valueArguments.get(i);
          if (argument.isNamed()) {
            namedMode = true;
          } else {
            ValueParameterDescriptor param = valueParameters.get(i);
            builder.append(renderParameter(param, false));
            if (i <= currentParameterIndex
                && !isArgumentTypeValid(bindingContext, argument, param)) {
              isGrey = true;
            }
            usedIndexes[i] = true;
          }
        } else {
          ValueParameterDescriptor param = valueParameters.get(i);
          builder.append(renderParameter(param, false));
        }
      }

      if (namedMode) {
        boolean takeAnyArgument = true;
        if (valueArguments.size() > i) {
          JetValueArgument argument = valueArguments.get(i);
          if (argument.isNamed()) {
            for (int j = 0; j < valueParameters.size(); ++j) {
              JetSimpleNameExpression referenceExpression =
                  argument.getArgumentName().getReferenceExpression();
              ValueParameterDescriptor param = valueParameters.get(j);
              if (referenceExpression != null
                  && !usedIndexes[j]
                  && param.getName().equals(referenceExpression.getReferencedNameAsName())) {
                takeAnyArgument = false;
                usedIndexes[j] = true;
                builder.append(renderParameter(param, true));
                if (i < currentParameterIndex
                    && !isArgumentTypeValid(bindingContext, argument, param)) {
                  isGrey = true;
                }
                break;
              }
            }
          }
        }

        if (takeAnyArgument) {
          if (i < currentParameterIndex) {
            isGrey = true;
          }

          for (int j = 0; j < valueParameters.size(); ++j) {
            ValueParameterDescriptor param = valueParameters.get(j);
            if (!usedIndexes[j]) {
              usedIndexes[j] = true;
              builder.append(renderParameter(param, true));
              break;
            }
          }
        }
      }

      if (highlightParameter) {
        boldEndOffset = builder.length();
      }
    }

    if (valueParameters.size() == 0) {
      builder.append(CodeInsightBundle.message("parameter.info.no.parameters"));
    }

    assert !builder.toString().isEmpty()
        : "A message about 'no parameters' or some parameters should be present: "
            + functionDescriptor;

    Color color =
        isResolvedToDescriptor(argumentList, functionDescriptor, bindingContext)
            ? GREEN_BACKGROUND
            : context.getDefaultParameterColor();
    context.setupUIComponentPresentation(
        builder.toString(), boldStartOffset, boldEndOffset, isGrey, isDeprecated, false, color);
  }