/*
 * Copyright 2003-2016 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 jetbrains.mps.workbench.choose;

import jetbrains.mps.smodel.ModelAccessHelper;
import jetbrains.mps.util.Computable;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.mps.openapi.model.SModel;
import org.jetbrains.mps.openapi.model.SModelReference;
import org.jetbrains.mps.openapi.module.SRepository;
import org.jetbrains.mps.openapi.module.SearchScope;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * Gives access to {@linkplain SearchScope scope's} models as iterable collection of {@link SModelReference},
 * to use in {@link ChooseByNameData#setScope(Iterable, Iterable)}.
 * @author Artem Tikhomirov
 * @since 3.4
 */
public final class ModelScopeIterable implements Iterable<SModelReference> {
  private final SearchScope myScope;
  private final SRepository myRepo;

  public ModelScopeIterable(@NotNull  SearchScope scope, @NotNull SRepository repo) {
    myScope = scope;
    myRepo = repo;
  }

  @Override
  public Iterator<SModelReference> iterator() {
    List<SModelReference> refs = new ModelAccessHelper(myRepo).runReadAction(new Computable<List<SModelReference>>() {
      @Override
      public List<SModelReference> compute() {
        ArrayList<SModelReference> rv = new ArrayList<SModelReference>(100); // if we got few models, it's unlikely we care to use choose by name functionality
        for (SModel m : myScope.getModels()) {
          rv.add(m.getReference());
        }
        return rv;
      }
    });
    return refs.iterator();
  }
}
