private static boolean compareParamTypes(
      @NotNull PsiManager manager, @NotNull PsiType type1, @NotNull PsiType type2) {
    if (type1 instanceof PsiArrayType) {
      return type2 instanceof PsiArrayType
          && compareParamTypes(
              manager,
              ((PsiArrayType) type1).getComponentType(),
              ((PsiArrayType) type2).getComponentType());
    }

    if (!(type1 instanceof PsiClassType) || !(type2 instanceof PsiClassType)) {
      return type1.equals(type2);
    }

    PsiClass class1 = ((PsiClassType) type1).resolve();
    PsiClass class2 = ((PsiClassType) type2).resolve();

    if (class1 instanceof PsiTypeParameter && class2 instanceof PsiTypeParameter) {
      return Comparing.equal(class1.getName(), class2.getName())
          && ((PsiTypeParameter) class1).getIndex() == ((PsiTypeParameter) class2).getIndex();
    }

    return manager.areElementsEquivalent(class1, class2);
  }
  public static boolean isMethodEquivalentTo(@NotNull PsiMethod method1, PsiElement another) {
    if (method1 == another) return true;
    if (!(another instanceof PsiMethod)) return false;
    PsiMethod method2 = (PsiMethod) another;
    if (!another.isValid()) return false;
    if (!method1.getName().equals(method2.getName())) return false;
    PsiClass aClass1 = method1.getContainingClass();
    PsiClass aClass2 = method2.getContainingClass();
    PsiManager manager = method1.getManager();
    if (!(aClass1 != null && aClass2 != null && manager.areElementsEquivalent(aClass1, aClass2)))
      return false;

    PsiParameter[] parameters1 = method1.getParameterList().getParameters();
    PsiParameter[] parameters2 = method2.getParameterList().getParameters();
    if (parameters1.length != parameters2.length) return false;
    for (int i = 0; i < parameters1.length; i++) {
      PsiParameter parameter1 = parameters1[i];
      PsiParameter parameter2 = parameters2[i];
      PsiType type1 = parameter1.getType();
      PsiType type2 = parameter2.getType();
      if (!compareParamTypes(manager, type1, type2)) return false;
    }
    return true;
  }
  public static int insertClassReference(
      PsiClass psiClass, PsiFile file, int startOffset, int endOffset) {
    final Project project = file.getProject();
    PsiDocumentManager documentManager = PsiDocumentManager.getInstance(project);
    documentManager.commitAllDocuments();

    final PsiManager manager = file.getManager();

    final Document document =
        FileDocumentManager.getInstance().getDocument(file.getViewProvider().getVirtualFile());

    final PsiReference reference = file.findReferenceAt(startOffset);
    if (reference != null) {
      final PsiElement resolved = reference.resolve();
      if (resolved instanceof PsiClass) {
        if (((PsiClass) resolved).getQualifiedName() == null
            || manager.areElementsEquivalent(psiClass, resolved)) {
          return endOffset;
        }
      }
    }

    String name = psiClass.getName();
    if (name == null) {
      return endOffset;
    }

    assert document != null;
    document.replaceString(startOffset, endOffset, name);

    int newEndOffset = startOffset + name.length();
    final RangeMarker toDelete = insertTemporary(newEndOffset, document, " ");

    documentManager.commitAllDocuments();

    PsiElement element = file.findElementAt(startOffset);
    if (element instanceof PsiIdentifier) {
      PsiElement parent = element.getParent();
      if (parent instanceof PsiJavaCodeReferenceElement
          && !((PsiJavaCodeReferenceElement) parent).isQualified()
          && !(parent.getParent() instanceof PsiPackageStatement)) {
        PsiJavaCodeReferenceElement ref = (PsiJavaCodeReferenceElement) parent;

        if (psiClass.isValid()
            && !psiClass.getManager().areElementsEquivalent(psiClass, resolveReference(ref))) {
          final boolean staticImport = ref instanceof PsiImportStaticReferenceElement;
          PsiElement newElement;
          try {
            newElement =
                staticImport
                    ? ((PsiImportStaticReferenceElement) ref).bindToTargetClass(psiClass)
                    : ref.bindToElement(psiClass);
          } catch (IncorrectOperationException e) {
            return endOffset; // can happen if fqn contains reserved words, for example
          }

          final RangeMarker rangeMarker = document.createRangeMarker(newElement.getTextRange());
          documentManager.doPostponedOperationsAndUnblockDocument(document);
          documentManager.commitDocument(document);

          newElement =
              CodeInsightUtilCore.findElementInRange(
                  file,
                  rangeMarker.getStartOffset(),
                  rangeMarker.getEndOffset(),
                  PsiJavaCodeReferenceElement.class,
                  JavaLanguage.INSTANCE);
          rangeMarker.dispose();
          if (newElement != null) {
            newEndOffset = newElement.getTextRange().getEndOffset();
            if (!(newElement instanceof PsiReferenceExpression)) {
              PsiReferenceParameterList parameterList =
                  ((PsiJavaCodeReferenceElement) newElement).getParameterList();
              if (parameterList != null) {
                newEndOffset = parameterList.getTextRange().getStartOffset();
              }
            }

            if (!staticImport
                && !psiClass
                    .getManager()
                    .areElementsEquivalent(psiClass, resolveReference((PsiReference) newElement))
                && !PsiUtil.isInnerClass(psiClass)) {
              final String qName = psiClass.getQualifiedName();
              if (qName != null) {
                document.replaceString(
                    newElement.getTextRange().getStartOffset(), newEndOffset, qName);
                newEndOffset = newElement.getTextRange().getStartOffset() + qName.length();
              }
            }
          }
        }
      }
    }

    if (toDelete.isValid()) {
      document.deleteString(toDelete.getStartOffset(), toDelete.getEndOffset());
    }

    return newEndOffset;
  }