/*
 * Copyright 2000-2013 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.psi.search.searches;

import com.intellij.openapi.extensions.ExtensionPointName;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiReference;
import com.intellij.psi.search.*;
import com.intellij.util.*;
import com.intellij.util.containers.ContainerUtil;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * @author max
 */
public class ReferencesSearch extends ExtensibleQueryFactory<PsiReference, ReferencesSearch.SearchParameters> {
  public static ExtensionPointName<QueryExecutor> EP_NAME = ExtensionPointName.create("com.intellij.referencesSearch");
  private static final ReferencesSearch INSTANCE = new ReferencesSearch();

  private ReferencesSearch() {
  }

  public static class SearchParameters {
    private final PsiElement myElementToSearch;
    private final SearchScope myScope;
    private final boolean myIgnoreAccessScope;
    private final SearchRequestCollector myOptimizer;
    private final boolean isSharedOptimizer;

    public SearchParameters(@NotNull PsiElement elementToSearch, SearchScope scope, boolean ignoreAccessScope, @Nullable SearchRequestCollector optimizer) {
      myElementToSearch = elementToSearch;
      myScope = scope;
      myIgnoreAccessScope = ignoreAccessScope;
      isSharedOptimizer = optimizer != null;
      myOptimizer = optimizer == null ? new SearchRequestCollector(new SearchSession()) : optimizer;
    }

    public SearchParameters(@NotNull final PsiElement elementToSearch, final SearchScope scope, final boolean ignoreAccessScope) {
      this(elementToSearch, scope, ignoreAccessScope, null);
    }

    @NotNull
    public PsiElement getElementToSearch() {
      return myElementToSearch;
    }

    /**
     * Use {@link #getEffectiveSearchScope} instead
     */
    @Deprecated()
    public SearchScope getScope() {
      return myScope;
    }

    public boolean isIgnoreAccessScope() {
      return myIgnoreAccessScope;
    }

    @NotNull
    public SearchRequestCollector getOptimizer() {
      return myOptimizer;
    }

    @NotNull
    public SearchScope getEffectiveSearchScope () {
      if (myIgnoreAccessScope) {
        return myScope;
      }
      SearchScope accessScope = PsiSearchHelper.SERVICE.getInstance(myElementToSearch.getProject()).getUseScope(myElementToSearch);
      return myScope.intersectWith(accessScope);
    }
  }

  public static Query<PsiReference> search(@NotNull PsiElement element) {
    return search(element, GlobalSearchScope.allScope(element.getProject()), false);
  }

  public static Query<PsiReference> search(@NotNull PsiElement element, @NotNull SearchScope searchScope) {
    return search(element, searchScope, false);
  }

  public static Query<PsiReference> search(@NotNull PsiElement element, @NotNull SearchScope searchScope, boolean ignoreAccessScope) {
    return search(new SearchParameters(element, searchScope, ignoreAccessScope));
  }

  public static Query<PsiReference> search(@NotNull final SearchParameters parameters) {
    final Query<PsiReference> result = INSTANCE.createQuery(parameters);
    if (parameters.isSharedOptimizer) {
      return uniqueResults(result);
    }

    final SearchRequestCollector requests = parameters.getOptimizer();

    final PsiElement element = parameters.getElementToSearch();

    return uniqueResults(new MergeQuery<PsiReference>(result, new SearchRequestQuery(element.getProject(), requests)));
  }

  private static UniqueResultsQuery<PsiReference, ReferenceDescriptor> uniqueResults(Query<PsiReference> composite) {
    return new UniqueResultsQuery<PsiReference, ReferenceDescriptor>(composite, ContainerUtil.<ReferenceDescriptor>canonicalStrategy(), ReferenceDescriptor.MAPPER);
  }

  public static void searchOptimized(@NotNull PsiElement element,
                                     @NotNull SearchScope searchScope,
                                     boolean ignoreAccessScope,
                                     @NotNull SearchRequestCollector collector,
                                     @NotNull final Processor<PsiReference> processor) {
    searchOptimized(element, searchScope, ignoreAccessScope, collector, false, new PairProcessor<PsiReference, SearchRequestCollector>() {
      @Override
      public boolean process(PsiReference psiReference, SearchRequestCollector collector) {
        return processor.process(psiReference);
      }
    });
  }

  public static void searchOptimized(@NotNull PsiElement element,
                                     @NotNull SearchScope searchScope,
                                     boolean ignoreAccessScope,
                                     @NotNull SearchRequestCollector collector,
                                     final boolean inReadAction,
                                     @NotNull PairProcessor<PsiReference, SearchRequestCollector> processor) {
    final SearchRequestCollector nested = new SearchRequestCollector(collector.getSearchSession());
    Query<PsiReference> query = search(new SearchParameters(element, searchScope, ignoreAccessScope, nested));
    collector.searchQuery(new QuerySearchRequest(query, nested, inReadAction, processor));
  }
}