// Copyright (C) 2014 The Android Open Source Project
//
// 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.google.gerrit.server.restapi.change;

import com.google.gerrit.extensions.common.Input;
import com.google.gerrit.extensions.registration.DynamicMap;
import com.google.gerrit.extensions.restapi.AuthException;
import com.google.gerrit.extensions.restapi.ChildCollection;
import com.google.gerrit.extensions.restapi.IdString;
import com.google.gerrit.extensions.restapi.ResourceConflictException;
import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
import com.google.gerrit.extensions.restapi.Response;
import com.google.gerrit.extensions.restapi.RestView;
import com.google.gerrit.reviewdb.client.Project;
import com.google.gerrit.server.change.ChangeEditResource;
import com.google.gerrit.server.change.ChangeResource;
import com.google.gerrit.server.edit.ChangeEditModifier;
import com.google.gerrit.server.git.GitRepositoryManager;
import com.google.gerrit.server.permissions.PermissionBackendException;
import com.google.gerrit.server.project.InvalidChangeOperationException;
import com.google.gerrit.server.update.BatchUpdate;
import com.google.gerrit.server.update.RetryHelper;
import com.google.gerrit.server.update.RetryingRestCollectionView;
import com.google.gwtorm.server.OrmException;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import java.io.IOException;
import org.eclipse.jgit.lib.Repository;

@Singleton
public class RebaseChangeEdit
    implements ChildCollection<ChangeResource, ChangeEditResource.Rebase> {

  private final DynamicMap<RestView<ChangeEditResource.Rebase>> views;

  @Inject
  RebaseChangeEdit(DynamicMap<RestView<ChangeEditResource.Rebase>> views) {
    this.views = views;
  }

  @Override
  public DynamicMap<RestView<ChangeEditResource.Rebase>> views() {
    return views;
  }

  @Override
  public RestView<ChangeResource> list() throws ResourceNotFoundException {
    throw new ResourceNotFoundException();
  }

  @Override
  public ChangeEditResource.Rebase parse(ChangeResource parent, IdString id)
      throws ResourceNotFoundException {
    throw new ResourceNotFoundException();
  }

  @Singleton
  public static class Rebase
      extends RetryingRestCollectionView<
          ChangeResource, ChangeEditResource.Rebase, Input, Response<?>> {
    private final GitRepositoryManager repositoryManager;
    private final ChangeEditModifier editModifier;

    @Inject
    Rebase(
        RetryHelper retryHelper,
        GitRepositoryManager repositoryManager,
        ChangeEditModifier editModifier) {
      super(retryHelper);
      this.repositoryManager = repositoryManager;
      this.editModifier = editModifier;
    }

    @Override
    protected Response<?> applyImpl(
        BatchUpdate.Factory updateFactory, ChangeResource rsrc, Input in)
        throws AuthException, ResourceConflictException, IOException, OrmException,
            PermissionBackendException {
      Project.NameKey project = rsrc.getProject();
      try (Repository repository = repositoryManager.openRepository(project)) {
        editModifier.rebaseEdit(repository, rsrc.getNotes());
      } catch (InvalidChangeOperationException e) {
        throw new ResourceConflictException(e.getMessage());
      }
      return Response.none();
    }
  }
}