/*
 * Copyright 2000-2015 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.dvcs.ui;

import com.intellij.dvcs.repo.AbstractRepositoryManager;
import com.intellij.dvcs.repo.Repository;
import com.intellij.openapi.actionSystem.AnActionEvent;
import com.intellij.openapi.actionSystem.CommonDataKeys;
import com.intellij.openapi.project.DumbAwareAction;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.util.containers.ContainerUtil;
import com.intellij.vcs.log.CommitId;
import com.intellij.vcs.log.Hash;
import com.intellij.vcs.log.VcsLog;
import com.intellij.vcs.log.VcsLogDataKeys;
import com.intellij.vcs.log.data.LoadingDetails;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.List;

public abstract class VcsLogSingleCommitAction<Repo extends Repository> extends DumbAwareAction {

  @Override
  public void actionPerformed(@NotNull AnActionEvent e) {
    Project project = e.getRequiredData(CommonDataKeys.PROJECT);
    VcsLog log = e.getRequiredData(VcsLogDataKeys.VCS_LOG);

    CommitId commit = ContainerUtil.getFirstItem(log.getSelectedCommits());
    assert commit != null;
    Repo repository = getRepositoryForRoot(project, commit.getRoot());
    assert repository != null;

    actionPerformed(repository, commit.getHash());
  }

  @Override
  public void update(@NotNull AnActionEvent e) {
    Project project = e.getProject();
    VcsLog log = e.getData(VcsLogDataKeys.VCS_LOG);
    if (project == null || log == null) {
      e.getPresentation().setEnabledAndVisible(false);
      return;
    }

    List<CommitId> commits = log.getSelectedCommits();
    if (commits.isEmpty()) {
      e.getPresentation().setEnabledAndVisible(false);
    }
    else {
      CommitId commit = ContainerUtil.getFirstItem(commits);
      assert commit != null;
      Repo repository = getRepositoryForRoot(project, commit.getRoot());

      if (repository == null) {
        e.getPresentation().setEnabledAndVisible(false);
      }
      else {
        e.getPresentation().setVisible(isVisible(project, repository, commit.getHash()));
        e.getPresentation().setEnabled(commits.size() == 1 && isEnabled(repository, commit.getHash()));
      }
    }
  }

  protected abstract void actionPerformed(@NotNull Repo repository, @NotNull Hash commit);

  protected boolean isEnabled(@NotNull Repo repository, @NotNull Hash commit) {
    return true;
  }

  protected boolean isVisible(@NotNull final Project project, @NotNull Repo repository, @NotNull Hash hash) {
    return !getRepositoryManager(project).isExternal(repository);
  }

  @NotNull
  protected abstract AbstractRepositoryManager<Repo> getRepositoryManager(@NotNull Project project);

  @Nullable
  protected abstract Repo getRepositoryForRoot(@NotNull Project project, @NotNull VirtualFile root);
}

@@ -1187,57 +1187,8 @@
 ys;%0A
-import com.intellij.vcs.log.data.LoadingDetails;%0A
 impo
@@ -2266,23 +2266,25 @@
     
-%7D%0A    else %7B%0A  
+  return;%0A    %7D%0A%0A
     
@@ -2338,18 +2338,16 @@
 mmits);%0A
-  
     asse
@@ -2369,18 +2369,16 @@
 ll;%0A    
-  
 Repo rep
@@ -2437,18 +2437,16 @@
 ot());%0A%0A
-  
     if (
@@ -2465,34 +2465,32 @@
 = null) %7B%0A      
-  
 e.getPresentatio
@@ -2532,27 +2532,23 @@
     
-%7D%0A      else %7B
+return;
 %0A    
+%7D%0A%0A
     
@@ -2633,20 +2633,16 @@
 ));%0A    
- 
-   
 e.getPre
@@ -2733,22 +2733,8 @@
 ));%0A
-      %7D%0A    %7D%0A
   %7D%0A

remove else clauses, use return instead