/*
 * Copyright 2006-2012 Dave Griffith, Bas Leijdekkers
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.siyeh.ig.psiutils;

import com.intellij.codeInspection.reference.RefMethod;
import com.intellij.codeInspection.reference.RefOverridable;
import com.intellij.util.containers.Stack;

import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

public final class MethodInheritanceUtils {

  private MethodInheritanceUtils() {}

  public static Set<RefOverridable> calculateSiblingReferences(RefMethod method) {
    final Set<RefOverridable> siblingReferences = new HashSet<>();
    final Stack<RefOverridable> pendingReferences = new Stack<>();
    pendingReferences.add(method);
    while (!pendingReferences.isEmpty()) {
      final RefOverridable referenceToAnalyze = pendingReferences.pop();
      siblingReferences.add(referenceToAnalyze);
      final Collection<? extends RefOverridable> overridingReferences = referenceToAnalyze.getDerivedReferences();
      for (RefOverridable overridingReference : overridingReferences) {
        if (!siblingReferences.contains(overridingReference) &&
            !pendingReferences.contains(overridingReference)) {
          pendingReferences.add(overridingReference);
        }
      }
      if (referenceToAnalyze instanceof RefMethod) {
        final Collection<RefMethod> superMethods = ((RefMethod)referenceToAnalyze).getSuperMethods();
        for (RefMethod superMethod : superMethods) {
          if (!siblingReferences.contains(superMethod) &&
              !pendingReferences.contains(superMethod)) {
            pendingReferences.add(superMethod);
          }
        }
      }

    }
    return siblingReferences;
  }
}
