/*
 * 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 org.jetbrains.idea.maven.utils;

import com.intellij.codeInsight.AttachSourcesProvider;
import com.intellij.notification.Notification;
import com.intellij.notification.NotificationType;
import com.intellij.notification.Notifications;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.roots.LibraryOrderEntry;
import com.intellij.openapi.roots.OrderEntry;
import com.intellij.openapi.roots.ProjectRootManager;
import com.intellij.openapi.util.ActionCallback;
import com.intellij.openapi.util.AsyncResult;
import com.intellij.psi.PsiFile;
import com.intellij.util.Consumer;
import gnu.trove.THashSet;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.idea.maven.importing.MavenRootModelAdapter;
import org.jetbrains.idea.maven.model.MavenArtifact;
import org.jetbrains.idea.maven.model.MavenId;
import org.jetbrains.idea.maven.project.MavenArtifactDownloader;
import org.jetbrains.idea.maven.project.MavenProject;
import org.jetbrains.idea.maven.project.MavenProjectsManager;
import org.jetbrains.idea.maven.project.ProjectBundle;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;

public class MavenAttachSourcesProvider implements AttachSourcesProvider {
  @Override
  @NotNull
  public Collection<AttachSourcesAction> getActions(final List<LibraryOrderEntry> orderEntries, final PsiFile psiFile) {
    Collection<MavenProject> projects = getMavenProjects(psiFile);
    if (projects.isEmpty()) return Collections.emptyList();
    if (findArtifacts(projects, orderEntries).isEmpty()) return Collections.emptyList();

    return Collections.singleton(new AttachSourcesAction() {
      @Override
      public String getName() {
        return ProjectBundle.message("maven.action.download.sources");
      }

      @Override
      public String getBusyText() {
        return ProjectBundle.message("maven.action.download.sources.busy.text");
      }

      @Override
      public ActionCallback perform(List<LibraryOrderEntry> orderEntries) {
        // may have been changed by this time...
        Collection<MavenProject> mavenProjects = getMavenProjects(psiFile);
        if (mavenProjects.isEmpty()) {
          return ActionCallback.REJECTED;
        }

        MavenProjectsManager manager = MavenProjectsManager.getInstance(psiFile.getProject());

        Collection<MavenArtifact> artifacts = findArtifacts(mavenProjects, orderEntries);
        if (artifacts.isEmpty()) return ActionCallback.REJECTED;

        final AsyncResult<MavenArtifactDownloader.DownloadResult> result = new AsyncResult<>();
        manager.scheduleArtifactsDownloading(mavenProjects, artifacts, true, false, result);

        final ActionCallback resultWrapper = new ActionCallback();

        result.doWhenDone((Consumer<MavenArtifactDownloader.DownloadResult>)downloadResult -> {
          if (!downloadResult.unresolvedSources.isEmpty()) {
            final StringBuilder message = new StringBuilder();

            message.append("<html>Sources not found for:");

            int count = 0;
            for (MavenId each : downloadResult.unresolvedSources) {
              if (count++ > 5) {
                message.append("<br>and more...");
                break;
              }
              message.append("<br>").append(each.getDisplayString());
            }
            message.append("</html>");

            Notifications.Bus.notify(new Notification(MavenUtil.MAVEN_NOTIFICATION_GROUP,
                                                      "Cannot download sources",
                                                      message.toString(),
                                                      NotificationType.WARNING),
                                     psiFile.getProject());
          }

          if (downloadResult.resolvedSources.isEmpty()) {
            resultWrapper.setRejected();
          }
          else {
            resultWrapper.setDone();
          }
        });

        return resultWrapper;
      }
    });
  }

  private static Collection<MavenArtifact> findArtifacts(Collection<MavenProject> mavenProjects, List<LibraryOrderEntry> orderEntries) {
    Collection<MavenArtifact> artifacts = new THashSet<>();
    for (MavenProject each : mavenProjects) {
      for (LibraryOrderEntry entry : orderEntries) {
        final MavenArtifact artifact = MavenRootModelAdapter.findArtifact(each, entry.getLibrary());
        if (artifact != null && !"system".equals(artifact.getScope())) {
          artifacts.add(artifact);
        }
      }
    }
    return artifacts;
  }

  private static Collection<MavenProject> getMavenProjects(PsiFile psiFile) {
    Project project = psiFile.getProject();
    Collection<MavenProject> result = new ArrayList<>();
    for (OrderEntry each : ProjectRootManager.getInstance(project).getFileIndex().getOrderEntriesForFile(psiFile.getVirtualFile())) {
      MavenProject mavenProject = MavenProjectsManager.getInstance(project).findProject(each.getOwnerModule());
      if (mavenProject != null) result.add(mavenProject);
    }
    return result;
  }
}