/*
 * Copyright (c) 2012, 2015 Eike Stepper (Berlin, Germany) and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Eike Stepper - initial API and implementation
 */
package org.eclipse.emf.cdo.security.presentation;

import org.eclipse.emf.common.ui.viewer.IViewerProvider;
import org.eclipse.emf.edit.domain.EditingDomain;
import org.eclipse.emf.edit.domain.IEditingDomainProvider;
import org.eclipse.emf.edit.ui.action.ControlAction;
import org.eclipse.emf.edit.ui.action.CreateChildAction;
import org.eclipse.emf.edit.ui.action.CreateSiblingAction;
import org.eclipse.emf.edit.ui.action.EditingDomainActionBarContributor;
import org.eclipse.emf.edit.ui.action.LoadResourceAction;
import org.eclipse.emf.edit.ui.action.ValidateAction;

import org.eclipse.jface.action.Action;
import org.eclipse.jface.action.ActionContributionItem;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.action.IContributionItem;
import org.eclipse.jface.action.IContributionManager;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.IToolBarManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.jface.action.SubContributionItem;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.PartInitException;

import java.util.ArrayList;
import java.util.Collection;

/**
 * This is the action bar contributor for the Security model editor.
 * <!-- begin-user-doc -->
 * <!-- end-user-doc -->
 * @generated
 */
public class SecurityActionBarContributor extends EditingDomainActionBarContributor implements ISelectionChangedListener
{
  /**
   * This keeps track of the active editor.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
  protected IEditorPart activeEditorPart;

  /**
   * This keeps track of the current selection provider.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
  protected ISelectionProvider selectionProvider;

  /**
   * This action opens the Properties view.
   * <!-- begin-user-doc -->
   * <!-- end-user-doc -->
   * @generated
   */
  protected IAction showPropertiesViewAction = new Action(
      SecurityEditorPlugin.INSTANCE.getString("_UI_ShowPropertiesView_menu_item"))//$NON-NLS-1$
      {
    @Override
    public void run()
    {
      try
      {
        getPage().showView("org.eclipse.ui.views.PropertySheet"); //$NON-NLS-1$
      }
      catch (PartInitException exception)
      {
        SecurityEditorPlugin.INSTANCE.log(exception);
      }
    }
      };

      /**
       * This action refreshes the viewer of the current editor if the editor
       * implements {@link org.eclipse.emf.common.ui.viewer.IViewerProvider}.
       * <!-- begin-user-doc -->
       * <!-- end-user-doc -->
       * @generated
       */
      protected IAction refreshViewerAction = new Action(
          SecurityEditorPlugin.INSTANCE.getString("_UI_RefreshViewer_menu_item"))//$NON-NLS-1$
          {
        @Override
        public boolean isEnabled()
        {
          return activeEditorPart instanceof IViewerProvider;
        }

        @Override
        public void run()
        {
          if (activeEditorPart instanceof IViewerProvider)
          {
            Viewer viewer = ((IViewerProvider)activeEditorPart).getViewer();
            if (viewer != null)
            {
              viewer.refresh();
            }
          }
        }
          };

          /**
           * This will contain one {@link org.eclipse.emf.edit.ui.action.CreateChildAction} corresponding to each descriptor
           * generated for the current selection by the item provider.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected Collection<IAction> createChildActions;

          /**
           * This is the menu manager into which menu contribution items should be added for CreateChild actions.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected IMenuManager createChildMenuManager;

          /**
           * This will contain one {@link org.eclipse.emf.edit.ui.action.CreateSiblingAction} corresponding to each descriptor
           * generated for the current selection by the item provider.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected Collection<IAction> createSiblingActions;

          /**
           * This is the menu manager into which menu contribution items should be added for CreateSibling actions.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected IMenuManager createSiblingMenuManager;

          /**
           * This creates an instance of the contributor.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          public SecurityActionBarContributor()
          {
            super(ADDITIONS_LAST_STYLE);
            loadResourceAction = new LoadResourceAction();
            validateAction = new ValidateAction();
            controlAction = new ControlAction();
          }

          /**
           * This adds Separators for editor additions to the tool bar.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          @Override
          public void contributeToToolBar(IToolBarManager toolBarManager)
          {
            toolBarManager.add(new Separator("security-settings")); //$NON-NLS-1$
            toolBarManager.add(new Separator("security-additions")); //$NON-NLS-1$
          }

          /**
           * This adds to the menu bar a menu and some separators for editor additions,
           * as well as the sub-menus for object creation items.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          @Override
          public void contributeToMenu(IMenuManager menuManager)
          {
            super.contributeToMenu(menuManager);

            IMenuManager submenuManager = new MenuManager(SecurityEditorPlugin.INSTANCE.getString("_UI_SecurityEditor_menu"), //$NON-NLS-1$
        "org.eclipse.emf.cdo.securityMenuID"); //$NON-NLS-1$
            menuManager.insertAfter("additions", submenuManager); //$NON-NLS-1$
            submenuManager.add(new Separator("settings")); //$NON-NLS-1$
            submenuManager.add(new Separator("actions")); //$NON-NLS-1$
            submenuManager.add(new Separator("additions")); //$NON-NLS-1$
            submenuManager.add(new Separator("additions-end")); //$NON-NLS-1$

            // Prepare for CreateChild item addition or removal.
            //
            createChildMenuManager = new MenuManager(SecurityEditorPlugin.INSTANCE.getString("_UI_CreateChild_menu_item")); //$NON-NLS-1$
            submenuManager.insertBefore("additions", createChildMenuManager); //$NON-NLS-1$

            // Prepare for CreateSibling item addition or removal.
            //
            createSiblingMenuManager = new MenuManager(SecurityEditorPlugin.INSTANCE.getString("_UI_CreateSibling_menu_item")); //$NON-NLS-1$
            submenuManager.insertBefore("additions", createSiblingMenuManager); //$NON-NLS-1$

            // Force an update because Eclipse hides empty menus now.
            //
            submenuManager.addMenuListener(new IMenuListener()
            {
              public void menuAboutToShow(IMenuManager menuManager)
              {
                menuManager.updateAll(true);
              }
            });

            addGlobalActions(submenuManager);
          }

          /**
           * When the active editor changes, this remembers the change and registers with it as a selection provider.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          @Override
          public void setActiveEditor(IEditorPart part)
          {
            super.setActiveEditor(part);
            activeEditorPart = part;

            // Switch to the new selection provider.
            //
            if (selectionProvider != null)
            {
              selectionProvider.removeSelectionChangedListener(this);
            }
            if (part == null)
            {
              selectionProvider = null;
            }
            else
            {
              selectionProvider = part.getSite().getSelectionProvider();
              selectionProvider.addSelectionChangedListener(this);

              // Fake a selection changed event to update the menus.
              //
              if (selectionProvider.getSelection() != null)
              {
                selectionChanged(new SelectionChangedEvent(selectionProvider, selectionProvider.getSelection()));
              }
            }
          }

          /**
           * This implements {@link org.eclipse.jface.viewers.ISelectionChangedListener},
           * handling {@link org.eclipse.jface.viewers.SelectionChangedEvent}s by querying for the children and siblings
           * that can be added to the selected object and updating the menus accordingly.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          public void selectionChanged(SelectionChangedEvent event)
          {
            // Remove any menu items for old selection.
            //
            if (createChildMenuManager != null)
            {
              depopulateManager(createChildMenuManager, createChildActions);
            }
            if (createSiblingMenuManager != null)
            {
              depopulateManager(createSiblingMenuManager, createSiblingActions);
            }

            // Query the new selection for appropriate new child/sibling descriptors
            //
            Collection<?> newChildDescriptors = null;
            Collection<?> newSiblingDescriptors = null;

            ISelection selection = event.getSelection();
            if (selection instanceof IStructuredSelection && ((IStructuredSelection)selection).size() == 1)
            {
              Object object = ((IStructuredSelection)selection).getFirstElement();

              EditingDomain domain = ((IEditingDomainProvider)activeEditorPart).getEditingDomain();

              newChildDescriptors = domain.getNewChildDescriptors(object, null);
              newSiblingDescriptors = domain.getNewChildDescriptors(null, object);
            }

            // Generate actions for selection; populate and redraw the menus.
            //
            createChildActions = generateCreateChildActions(newChildDescriptors, selection);
            createSiblingActions = generateCreateSiblingActions(newSiblingDescriptors, selection);

            if (createChildMenuManager != null)
            {
              populateManager(createChildMenuManager, createChildActions, null);
              createChildMenuManager.update(true);
            }
            if (createSiblingMenuManager != null)
            {
              populateManager(createSiblingMenuManager, createSiblingActions, null);
              createSiblingMenuManager.update(true);
            }
          }

          /**
           * This generates a {@link org.eclipse.emf.edit.ui.action.CreateChildAction} for each object in <code>descriptors</code>,
           * and returns the collection of these actions.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected Collection<IAction> generateCreateChildActions(Collection<?> descriptors, ISelection selection)
          {
            Collection<IAction> actions = new ArrayList<IAction>();
            if (descriptors != null)
            {
              for (Object descriptor : descriptors)
              {
                actions.add(new CreateChildAction(activeEditorPart, selection, descriptor));
              }
            }
            return actions;
          }

          /**
           * This generates a {@link org.eclipse.emf.edit.ui.action.CreateSiblingAction} for each object in <code>descriptors</code>,
           * and returns the collection of these actions.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected Collection<IAction> generateCreateSiblingActions(Collection<?> descriptors, ISelection selection)
          {
            Collection<IAction> actions = new ArrayList<IAction>();
            if (descriptors != null)
            {
              for (Object descriptor : descriptors)
              {
                actions.add(new CreateSiblingAction(activeEditorPart, selection, descriptor));
              }
            }
            return actions;
          }

          /**
           * This populates the specified <code>manager</code> with {@link org.eclipse.jface.action.ActionContributionItem}s
           * based on the {@link org.eclipse.jface.action.IAction}s contained in the <code>actions</code> collection,
           * by inserting them before the specified contribution item <code>contributionID</code>.
           * If <code>contributionID</code> is <code>null</code>, they are simply added.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected void populateManager(IContributionManager manager, Collection<? extends IAction> actions,
              String contributionID)
          {
            if (actions != null)
            {
              for (IAction action : actions)
              {
                if (contributionID != null)
                {
                  manager.insertBefore(contributionID, action);
                }
                else
                {
                  manager.add(action);
                }
              }
            }
          }

          /**
           * This removes from the specified <code>manager</code> all {@link org.eclipse.jface.action.ActionContributionItem}s
           * based on the {@link org.eclipse.jface.action.IAction}s contained in the <code>actions</code> collection.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          protected void depopulateManager(IContributionManager manager, Collection<? extends IAction> actions)
          {
            if (actions != null)
            {
              IContributionItem[] items = manager.getItems();
              for (int i = 0; i < items.length; i++)
              {
                // Look into SubContributionItems
                //
                IContributionItem contributionItem = items[i];
                while (contributionItem instanceof SubContributionItem)
                {
                  contributionItem = ((SubContributionItem)contributionItem).getInnerItem();
                }

                // Delete the ActionContributionItems with matching action.
                //
                if (contributionItem instanceof ActionContributionItem)
                {
                  IAction action = ((ActionContributionItem)contributionItem).getAction();
                  if (actions.contains(action))
                  {
                    manager.remove(contributionItem);
                  }
                }
              }
            }
          }

          /**
           * This populates the pop-up menu before it appears.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          @Override
          public void menuAboutToShow(IMenuManager menuManager)
          {
            super.menuAboutToShow(menuManager);
            MenuManager submenuManager = null;

            submenuManager = new MenuManager(SecurityEditorPlugin.INSTANCE.getString("_UI_CreateChild_menu_item")); //$NON-NLS-1$
            populateManager(submenuManager, createChildActions, null);
            menuManager.insertBefore("edit", submenuManager); //$NON-NLS-1$

            submenuManager = new MenuManager(SecurityEditorPlugin.INSTANCE.getString("_UI_CreateSibling_menu_item")); //$NON-NLS-1$
            populateManager(submenuManager, createSiblingActions, null);
            menuManager.insertBefore("edit", submenuManager); //$NON-NLS-1$
          }

          /**
           * This inserts global actions before the "additions-end" separator.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          @Override
          protected void addGlobalActions(IMenuManager menuManager)
          {
            menuManager.insertAfter("additions-end", new Separator("ui-actions")); //$NON-NLS-1$ //$NON-NLS-2$
            menuManager.insertAfter("ui-actions", showPropertiesViewAction); //$NON-NLS-1$

            refreshViewerAction.setEnabled(refreshViewerAction.isEnabled());
            menuManager.insertAfter("ui-actions", refreshViewerAction); //$NON-NLS-1$

            super.addGlobalActions(menuManager);
          }

          /**
           * This ensures that a delete action will clean up all references to deleted objects.
           * <!-- begin-user-doc -->
           * <!-- end-user-doc -->
           * @generated
           */
          @Override
          protected boolean removeAllReferencesOnDelete()
          {
            return true;
          }

}