/*
 * Copyright 2016 The Bazel Authors. All rights reserved.
 *
 * 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.idea.blaze.base.ide;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;
import com.google.idea.blaze.base.actions.BlazeProjectAction;
import com.google.idea.blaze.base.buildmodifier.BuildFileModifier;
import com.google.idea.blaze.base.buildmodifier.FileSystemModifier;
import com.google.idea.blaze.base.model.primitives.Kind;
import com.google.idea.blaze.base.model.primitives.Label;
import com.google.idea.blaze.base.model.primitives.WorkspacePath;
import com.google.idea.blaze.base.model.primitives.WorkspaceRoot;
import com.google.idea.blaze.base.projectview.ProjectViewManager;
import com.google.idea.blaze.base.projectview.ProjectViewSet;
import com.google.idea.blaze.base.scope.BlazeContext;
import com.google.idea.blaze.base.scope.Scope;
import com.google.idea.blaze.base.scope.ScopedOperation;
import com.google.idea.blaze.base.scope.output.PrintOutput;
import com.google.idea.blaze.base.scope.output.StatusOutput;
import com.google.idea.blaze.base.settings.Blaze;
import com.google.idea.blaze.base.sync.projectview.ImportRoots;
import com.google.idea.blaze.base.util.WorkspacePathUtil;
import com.intellij.history.LocalHistory;
import com.intellij.history.LocalHistoryAction;
import com.intellij.ide.IdeView;
import com.intellij.ide.util.DirectoryChooserUtil;
import com.intellij.openapi.actionSystem.AnActionEvent;
import com.intellij.openapi.actionSystem.LangDataKeys;
import com.intellij.openapi.actionSystem.Presentation;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.project.DumbAware;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.vfs.VfsUtil;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.psi.PsiDirectory;
import com.intellij.psi.PsiFile;
import com.intellij.psi.PsiManager;
import com.intellij.util.PlatformIcons;
import java.io.File;
import java.util.List;
import java.util.stream.Collectors;
import javax.annotation.Nullable;
import org.jetbrains.annotations.NotNull;

class NewBlazePackageAction extends BlazeProjectAction implements DumbAware {
  private static final Logger logger = Logger.getInstance(NewBlazePackageAction.class);

  private static final String BUILD_FILE_NAME = "BUILD";

  public NewBlazePackageAction() {
    super();
  }

  @Override
  protected void actionPerformedInBlazeProject(Project project, AnActionEvent event) {
    final IdeView view = event.getData(LangDataKeys.IDE_VIEW);
    Scope.root(
        new ScopedOperation() {
          @Override
          public void execute(@NotNull final BlazeContext context) {
            if (view == null || project == null) {
              return;
            }
            PsiDirectory directory = getOrChooseDirectory(project, view);

            if (directory == null) {
              return;
            }

            NewBlazePackageDialog newBlazePackageDialog =
                new NewBlazePackageDialog(project, directory);
            boolean isOk = newBlazePackageDialog.showAndGet();
            if (!isOk) {
              return;
            }

            final Label newRule = newBlazePackageDialog.getNewRule();
            final Kind newRuleKind = newBlazePackageDialog.getNewRuleKind();
            // If we returned OK, we should have a non null result
            logger.assertTrue(newRule != null);
            logger.assertTrue(newRuleKind != null);

            context.output(
                new StatusOutput(
                    String.format("Setting up a new %s package", Blaze.buildSystemName(project))));

            boolean success = createPackageOnDisk(project, context, newRule, newRuleKind);

            if (!success) {
              return;
            }

            File newDirectory =
                WorkspaceRoot.fromProject(project).fileForPath(newRule.blazePackage());
            VirtualFile virtualFile = VfsUtil.findFileByIoFile(newDirectory, true);
            // We just created this file, it should exist
            logger.assertTrue(virtualFile != null);
            PsiFile psiFile = PsiManager.getInstance(project).findFile(virtualFile);
            view.selectElement(psiFile);
          }
        });
  }

  private static Boolean createPackageOnDisk(
      @NotNull Project project,
      @NotNull BlazeContext context,
      @NotNull Label newRule,
      @NotNull Kind ruleKind) {
    LocalHistoryAction action;

    String actionName =
        String.format(
            "Creating %s package: %s", Blaze.buildSystemName(project), newRule.toString());
    LocalHistory localHistory = LocalHistory.getInstance();
    action = localHistory.startAction(actionName);

    // Create the package + BUILD file + rule
    FileSystemModifier fileSystemModifier = FileSystemModifier.getInstance(project);
    WorkspacePath newWorkspacePath = newRule.blazePackage();
    File newDirectory = fileSystemModifier.makeWorkspacePathDirs(newWorkspacePath);
    if (newDirectory == null) {
      String errorMessage =
          "Could not create new package directory: " + newWorkspacePath.toString();
      context.output(PrintOutput.error(errorMessage));
      return false;
    }
    File buildFile = fileSystemModifier.createFile(newWorkspacePath, BUILD_FILE_NAME);
    if (buildFile == null) {
      String errorMessage =
          "Could not create new BUILD file in package: " + newWorkspacePath.toString();
      context.output(PrintOutput.error(errorMessage));
      return false;
    }
    BuildFileModifier buildFileModifier = BuildFileModifier.getInstance();
    buildFileModifier.addRule(project, context, newRule, ruleKind);
    action.finish();

    return true;
  }

  @Override
  protected void updateForBlazeProject(Project project, @NotNull AnActionEvent event) {
    Presentation presentation = event.getPresentation();
    if (isEnabled(event)) {
      String text = String.format("New %s Package", Blaze.buildSystemName(project));
      presentation.setEnabledAndVisible(true);
      presentation.setText(text);
      presentation.setDescription(text);
      presentation.setIcon(PlatformIcons.PACKAGE_ICON);
    } else {
      presentation.setEnabledAndVisible(false);
    }
  }

  private boolean isEnabled(AnActionEvent event) {
    Project project = event.getProject();
    IdeView view = event.getData(LangDataKeys.IDE_VIEW);
    if (project == null || view == null) {
      return false;
    }

    List<PsiDirectory> directories = filterDirectories(project, view.getDirectories());
    if (directories.isEmpty()) {
      return false;
    }

    return true;
  }

  /** Filter out directories that do not live under the project's directories. */
  private static List<PsiDirectory> filterDirectories(Project project, PsiDirectory[] directories) {
    if (directories.length == 0) {
      return ImmutableList.of();
    }
    ProjectViewSet projectViewSet = ProjectViewManager.getInstance(project).getProjectViewSet();
    if (projectViewSet == null) {
      return ImmutableList.of();
    }
    WorkspaceRoot workspaceRoot = WorkspaceRoot.fromProject(project);
    ImportRoots importRoots =
        ImportRoots.builder(workspaceRoot, Blaze.getBuildSystem(project))
            .add(projectViewSet)
            .build();
    return Lists.newArrayList(directories)
        .stream()
        .filter(directory -> isUnderProjectViewDirectory(workspaceRoot, importRoots, directory))
        .collect(Collectors.toList());
  }

  private static boolean isUnderProjectViewDirectory(
      WorkspaceRoot workspaceRoot, ImportRoots importRoots, PsiDirectory directory) {
    VirtualFile virtualFile = directory.getVirtualFile();
    // Ignore jars, etc. and their contents, which are in an ArchiveFileSystem.
    if (!(virtualFile.isInLocalFileSystem())) {
      return false;
    }
    if (!workspaceRoot.isInWorkspace(virtualFile)) {
      return false;
    }
    WorkspacePath workspacePath = workspaceRoot.workspacePathFor(virtualFile);
    return WorkspacePathUtil.isUnderAnyWorkspacePath(importRoots.rootDirectories(), workspacePath);
  }

  @Nullable
  private static PsiDirectory getOrChooseDirectory(Project project, IdeView view) {
    List<PsiDirectory> dirs = filterDirectories(project, view.getDirectories());
    if (dirs.size() == 0) {
      return null;
    }
    if (dirs.size() == 1) {
      return dirs.get(0);
    } else {
      return DirectoryChooserUtil.selectDirectory(
          project, dirs.toArray(new PsiDirectory[dirs.size()]), null, "");
    }
  }
}