/*
 * Copyright 2000-2009 JetBrains s.r.o.
 *
 * 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.intellij.codeInsight.navigation;

import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFunctionalExpression;
import com.intellij.psi.PsiMethod;
import com.intellij.psi.search.SearchScope;
import com.intellij.psi.search.searches.DefinitionsScopedSearch;
import com.intellij.psi.search.searches.FunctionalExpressionSearch;
import com.intellij.psi.search.searches.OverridingMethodsSearch;
import com.intellij.util.Processor;
import com.intellij.util.QueryExecutor;
import com.intellij.util.containers.ContainerUtil;
import org.jetbrains.annotations.NotNull;

import java.util.ArrayList;

public class MethodImplementationsSearch implements QueryExecutor<PsiElement, DefinitionsScopedSearch.SearchParameters> {
  @Override
  public boolean execute(final @NotNull DefinitionsScopedSearch.SearchParameters queryParameters, final @NotNull Processor<PsiElement> consumer) {
    final PsiElement sourceElement = queryParameters.getElement();
    if (sourceElement instanceof PsiMethod) {
      return processImplementations((PsiMethod)sourceElement, consumer, queryParameters.getScope());
    }
    return true;
  }

  public static boolean processImplementations(final PsiMethod psiMethod, final Processor<PsiElement> consumer,
                                               final SearchScope searchScope) {
    if (!FunctionalExpressionSearch.search(psiMethod, searchScope).forEach(new Processor<PsiFunctionalExpression>() {
      @Override
      public boolean process(PsiFunctionalExpression expression) {
        return consumer.process(expression);
      }
    })) {
      return false;
    }
    final ArrayList<PsiMethod> methods = new ArrayList<PsiMethod>();
    getOverridingMethods(psiMethod, methods, searchScope);
    return ContainerUtil.process(methods, consumer);
  }

  public static void getOverridingMethods(PsiMethod method, ArrayList<PsiMethod> list, SearchScope scope) {
    for (PsiMethod psiMethod : OverridingMethodsSearch.search(method, scope, true)) {
      list.add(psiMethod);
    }
  }

  @SuppressWarnings("UnusedDeclaration")
  @Deprecated
  public static PsiMethod[] getMethodImplementations(final PsiMethod method, SearchScope scope) {
    ArrayList<PsiMethod> result = new ArrayList<PsiMethod>();

    getOverridingMethods(method, result, scope);
    return result.toArray(new PsiMethod[result.size()]);
  }
}