/*
 * Copyright 2000-2014 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.openapi.vcs.history;

import com.intellij.openapi.application.ApplicationManager;
import com.intellij.openapi.ui.MessageType;
import com.intellij.openapi.vcs.AbstractVcs;
import com.intellij.openapi.vcs.FilePath;
import com.intellij.openapi.vcs.VcsBundle;
import com.intellij.openapi.vcs.VcsException;
import com.intellij.openapi.vcs.annotate.AnnotationProvider;
import com.intellij.openapi.vcs.ex.ProjectLevelVcsManagerEx;
import com.intellij.openapi.vcs.ui.VcsBalloonProblemNotifier;
import com.intellij.openapi.wm.ToolWindow;
import com.intellij.openapi.wm.ToolWindowId;
import com.intellij.openapi.wm.ToolWindowManager;
import com.intellij.ui.content.Content;
import com.intellij.ui.content.ContentFactory;
import com.intellij.ui.content.ContentManager;
import com.intellij.util.BufferedListConsumer;
import com.intellij.util.Consumer;
import com.intellij.util.ContentsUtil;

import java.util.List;

/**
 * @author irengrig
 */
public class FileHistorySessionPartner implements VcsAppendableHistorySessionPartner {
  private final LimitHistoryCheck myLimitHistoryCheck;
  private FileHistoryPanelImpl myFileHistoryPanel;
  private final VcsHistoryProvider myVcsHistoryProvider;
  private final AnnotationProvider myAnnotationProvider;
  private final FilePath myPath;
  private final String myRepositoryPath;
  private final AbstractVcs myVcs;
  private final FileHistoryRefresherI myRefresherI;
  private volatile VcsAbstractHistorySession mySession;
  private final BufferedListConsumer<VcsFileRevision> myBuffer;

  public FileHistorySessionPartner(final VcsHistoryProvider vcsHistoryProvider, final AnnotationProvider annotationProvider,
                                   final FilePath path,
                                   final String repositoryPath,
                                   final AbstractVcs vcs,
                                   final FileHistoryRefresherI refresherI) {
    myVcsHistoryProvider = vcsHistoryProvider;
    myAnnotationProvider = annotationProvider;
    myPath = path;
    myLimitHistoryCheck = new LimitHistoryCheck(vcs.getProject(), path.getPath());
    myRepositoryPath = repositoryPath;
    myVcs = vcs;
    myRefresherI = refresherI;
    myBuffer = new BufferedListConsumer<VcsFileRevision>(5, new Consumer<List<VcsFileRevision>>() {
      public void consume(List<VcsFileRevision> vcsFileRevisions) {
        mySession.getRevisionList().addAll(vcsFileRevisions);
        final VcsHistorySession copy = mySession.copyWithCachedRevision();
        ApplicationManager.getApplication().invokeLater(new Runnable() {
          public void run() {
            ensureHistoryPanelCreated().getHistoryPanelRefresh().consume(copy);
          }
        });
      }
    }, 1000);
  }

  public void acceptRevision(VcsFileRevision revision) {
    myLimitHistoryCheck.checkNumber();
    myBuffer.consumeOne(revision);
  }

  private FileHistoryPanelImpl ensureHistoryPanelCreated() {
    if (myFileHistoryPanel == null) {
      ContentManager contentManager = ProjectLevelVcsManagerEx.getInstanceEx(myVcs.getProject()).getContentManager();
      final VcsHistorySession copy = mySession.copyWithCachedRevision();
      myFileHistoryPanel = new FileHistoryPanelImpl(myVcs, myPath, copy, myVcsHistoryProvider,
                                                    contentManager, myRefresherI);
    }
    return myFileHistoryPanel;
  }

  private FileHistoryPanelImpl resetHistoryPanel() {
    final VcsHistorySession copy = mySession.copyWithCachedRevision();
    if (myFileHistoryPanel == null) {
      ContentManager contentManager = ProjectLevelVcsManagerEx.getInstanceEx(myVcs.getProject()).getContentManager();
      myFileHistoryPanel = new FileHistoryPanelImpl(myVcs, myPath, copy, myVcsHistoryProvider,
                                                    contentManager, myRefresherI);
    } else {
      myFileHistoryPanel.getHistoryPanelRefresh().consume(copy);
    }
    return myFileHistoryPanel;
  }

  public void reportCreatedEmptySession(final VcsAbstractHistorySession session) {
    if (mySession != null && session != null && mySession.getRevisionList().equals(session.getRevisionList())) return;
    mySession = session;
    if (mySession != null) {
      mySession.shouldBeRefreshed();  // to init current revision!
    }
    ApplicationManager.getApplication().invokeLater(new Runnable() {
      public void run() {
        String actionName = VcsBundle.message(myPath.isDirectory() ? "action.name.file.history.dir" : "action.name.file.history",
                                              myPath.getName());
        ContentManager contentManager = ProjectLevelVcsManagerEx.getInstanceEx(myVcs.getProject()).getContentManager();

        myFileHistoryPanel = resetHistoryPanel();
        Content content = ContentFactory.SERVICE.getInstance().createContent(myFileHistoryPanel, actionName, true);
        ContentsUtil.addOrReplaceContent(contentManager, content, true);

        ToolWindow toolWindow = ToolWindowManager.getInstance(myVcs.getProject()).getToolWindow(ToolWindowId.VCS);
        assert toolWindow != null : "Version Control ToolWindow should be available at this point.";
        if (myRefresherI.isFirstTime()) {
          toolWindow.activate(null);
        }
      }
    });
  }

  public void reportException(VcsException exception) {
    VcsBalloonProblemNotifier.showOverVersionControlView(myVcs.getProject(),
                                                         VcsBundle.message("message.title.could.not.load.file.history") + ": " +
                                                         exception.getMessage(), MessageType.ERROR);
  }

  @Override
  public void beforeRefresh() {
    myLimitHistoryCheck.reset();
  }

  public void finished() {
    myBuffer.flush();
    ApplicationManager.getApplication().invokeLater(new Runnable() {
      public void run() {
        if (mySession == null) {
          // nothing to be done, exit
          return;
        }
        ensureHistoryPanelCreated().getHistoryPanelRefresh().finished();
      }
    });
  }

  @Override
  public void forceRefresh() {
    ApplicationManager.getApplication().invokeLater(new Runnable() {
      public void run() {
        if (mySession == null) {
          // nothing to be done, exit
          return;
        }
        ensureHistoryPanelCreated().scheduleRefresh(false);
      }
    });
  }
}