/*
 * This library is part of OpenCms -
 * the Open Source Content Management System
 *
 * Copyright (c) Alkacon Software GmbH & Co. KG (https://www.alkacon.com)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * For further information about Alkacon Software, please see the
 * company website: https://www.alkacon.com
 *
 * For further information about OpenCms, please see the
 * project website: https://www.opencms.org
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.opencms.ade.contenteditor.client;

import org.opencms.acacia.client.CmsAttributeHandler;
import org.opencms.acacia.client.CmsEditorBase;
import org.opencms.acacia.client.CmsUndoRedoHandler;
import org.opencms.acacia.client.CmsUndoRedoHandler.UndoRedoState;
import org.opencms.acacia.client.CmsValidationContext;
import org.opencms.acacia.client.CmsValidationHandler;
import org.opencms.acacia.client.CmsValueFocusHandler;
import org.opencms.acacia.client.I_CmsEntityRenderer;
import org.opencms.acacia.client.I_CmsInlineFormParent;
import org.opencms.acacia.client.I_CmsWidgetService;
import org.opencms.acacia.client.entity.CmsEntityBackend;
import org.opencms.acacia.shared.CmsEntity;
import org.opencms.acacia.shared.CmsEntityAttribute;
import org.opencms.acacia.shared.CmsEntityChangeEvent;
import org.opencms.acacia.shared.CmsEntityChangeEvent.ChangeType;
import org.opencms.acacia.shared.CmsTabInfo;
import org.opencms.acacia.shared.CmsType;
import org.opencms.acacia.shared.CmsValidationResult;
import org.opencms.ade.containerpage.client.CmsContainerpageController;
import org.opencms.ade.containerpage.client.CmsContentEditorHandler;
import org.opencms.ade.contenteditor.client.css.I_CmsLayoutBundle;
import org.opencms.ade.contenteditor.shared.CmsComplexWidgetData;
import org.opencms.ade.contenteditor.shared.CmsContentDefinition;
import org.opencms.ade.contenteditor.shared.CmsEditHandlerData;
import org.opencms.ade.contenteditor.shared.CmsSaveResult;
import org.opencms.ade.contenteditor.shared.rpc.I_CmsContentService;
import org.opencms.ade.contenteditor.shared.rpc.I_CmsContentServiceAsync;
import org.opencms.ade.contenteditor.widgetregistry.client.WidgetRegistry;
import org.opencms.ade.publish.client.CmsPublishDialog;
import org.opencms.ade.publish.shared.CmsPublishOptions;
import org.opencms.gwt.client.CmsCoreProvider;
import org.opencms.gwt.client.I_CmsEditableData;
import org.opencms.gwt.client.rpc.CmsRpcAction;
import org.opencms.gwt.client.rpc.CmsRpcPrefetcher;
import org.opencms.gwt.client.ui.CmsConfirmDialog;
import org.opencms.gwt.client.ui.CmsErrorDialog;
import org.opencms.gwt.client.ui.CmsInfoHeader;
import org.opencms.gwt.client.ui.CmsModelSelectDialog;
import org.opencms.gwt.client.ui.CmsNotification;
import org.opencms.gwt.client.ui.CmsNotification.Type;
import org.opencms.gwt.client.ui.CmsPushButton;
import org.opencms.gwt.client.ui.CmsToggleButton;
import org.opencms.gwt.client.ui.CmsToolbar;
import org.opencms.gwt.client.ui.I_CmsButton;
import org.opencms.gwt.client.ui.I_CmsButton.ButtonStyle;
import org.opencms.gwt.client.ui.I_CmsButton.Size;
import org.opencms.gwt.client.ui.I_CmsConfirmDialogHandler;
import org.opencms.gwt.client.ui.I_CmsModelSelectHandler;
import org.opencms.gwt.client.ui.input.CmsSelectBox;
import org.opencms.gwt.client.util.CmsDebugLog;
import org.opencms.gwt.client.util.CmsDomUtil;
import org.opencms.gwt.client.util.I_CmsSimpleCallback;
import org.opencms.gwt.shared.CmsGwtConstants;
import org.opencms.gwt.shared.CmsGwtLog;
import org.opencms.gwt.shared.CmsListInfoBean;
import org.opencms.util.CmsPair;
import org.opencms.util.CmsStringUtil;
import org.opencms.util.CmsUUID;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.TreeMap;

import com.google.gwt.core.client.GWT;
import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.core.client.Scheduler;
import com.google.gwt.core.client.Scheduler.ScheduledCommand;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.NodeList;
import com.google.gwt.dom.client.Style;
import com.google.gwt.dom.client.Style.Overflow;
import com.google.gwt.dom.client.Style.Position;
import com.google.gwt.dom.client.Style.Unit;
import com.google.gwt.dom.client.Style.VerticalAlign;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.logical.shared.CloseEvent;
import com.google.gwt.event.logical.shared.CloseHandler;
import com.google.gwt.event.logical.shared.SelectionEvent;
import com.google.gwt.event.logical.shared.SelectionHandler;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.Event.NativePreviewEvent;
import com.google.gwt.user.client.Event.NativePreviewHandler;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.Window.ClosingEvent;
import com.google.gwt.user.client.Window.ClosingHandler;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.rpc.SerializationException;
import com.google.gwt.user.client.rpc.ServiceDefTarget;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.PopupPanel;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.TextBox;

import elemental2.dom.DomGlobal;
import jsinterop.base.Js;
import jsinterop.base.JsPropertyMap;

/**
 * The content editor.<p>
 */
public final class CmsContentEditor extends CmsEditorBase {

    /**
     * CmsEntity change handler to watch for changes within given scopes and call the editor change handlers accordingly.<p>
     */
    class EditorChangeHandler implements ValueChangeHandler<CmsEntity> {

        /** The scope values. */
        Map<String, String> m_scopeValues;

        private Set<String> m_changedScopes = new HashSet<>();

        /** The change handler registration. */
        private HandlerRegistration m_handlerRegistration;

        /** The observed entity. */
        private CmsEntity m_observerdEntity;

        /**
         * Constructor.<p>
         *
         * @param entity the entity to observe
         * @param changeScopes the value scopes to watch for changes
         */
        public EditorChangeHandler(CmsEntity entity, Collection<String> changeScopes) {

            m_observerdEntity = entity;
            m_handlerRegistration = entity.addValueChangeHandler(this);
            m_scopeValues = new HashMap<String, String>();
            for (String scope : changeScopes) {
                m_scopeValues.put(scope, CmsContentDefinition.getValueForPath(m_observerdEntity, scope));
            }
        }

        /**
         * Removes this observer from the entities change handler registration and clears registered listeners.<p>
         */
        public void clear() {

            if (m_handlerRegistration != null) {
                m_handlerRegistration.removeHandler();
                m_handlerRegistration = null;
            }
            m_scopeValues.clear();
            m_observerdEntity = null;
        }

        /**
         * @see com.google.gwt.event.logical.shared.ValueChangeHandler#onValueChange(com.google.gwt.event.logical.shared.ValueChangeEvent)
         */
        public void onValueChange(ValueChangeEvent<CmsEntity> event) {

            final CmsEntity entity = event.getValue();
            if (event instanceof CmsEntityChangeEvent) {

                CmsEntityChangeEvent.ChangeType type = ((CmsEntityChangeEvent)event).getChangeType();
                for (String scope : m_scopeValues.keySet()) {
                    String scopeValue = CmsContentDefinition.getValueForPath(entity, scope);
                    String previousValue = m_scopeValues.get(scope);
                    if (((scopeValue != null) && !scopeValue.equals(previousValue))
                        || ((scopeValue == null) && (previousValue != null))) {
                        if (type == ChangeType.change) {
                            m_changedScopes.add(scope);
                        }
                        m_scopeValues.put(scope, scopeValue);
                    }
                }

            }
            Scheduler.get().scheduleFinally(new ScheduledCommand() {

                public void execute() {

                    if (m_changedScopes.size() > 0) {
                        Set<String> changedScopesCopy = new HashSet<>(m_changedScopes);
                        m_changedScopes.clear();
                        if (!changedScopesCopy.isEmpty()) {
                            callEditorChangeHandlers(changedScopesCopy);
                        }
                    }
                }
            });
        }
    }

    /** CSS marker class added to the html element when  the editor is active. */
    public static final String EDITOR_MARKER_CLASS = "opencms-editor-active";

    /** The add change listener method name. */
    private static final String ADD_CHANGE_LISTENER_METHOD = "cmsAddEntityChangeListener";

    /** The entity id selector prefix. */
    private static final String ENTITY_ID_SELECTOR_PREFIX = "[" + CmsGwtConstants.ATTR_DATA_ID + "*=\"";

    /** The entity id selector suffix. */
    private static final String ENTITY_ID_SELECTOR_SUFFIX = "\"]";

    /** The editable field selector. */
    private static final String FIELD_SELECTOR = "[" + CmsGwtConstants.ATTR_DATA_FIELD + "*=\"opencms://\"]";

    /** The get current entity method name. */
    private static final String GET_CURRENT_ENTITY_METHOD = "cmsGetCurrentEntity";

    /** The in-line editor instance. */
    private static CmsContentEditor INSTANCE;

    /** Flag indicating that an AJAX call for the editor change handler is running. */
    protected boolean m_callingChangeHandlers;

    /** The current content locale. */
    protected String m_locale;

    /** The on close call back. */
    protected I_CmsEditorCloseHandler m_onClose;

    /** The edit tool-bar. */
    protected CmsToolbar m_toolbar;

    /** The container element client id if available. */
    String m_clientId;

    /** The editor context. */
    CmsEditorContext m_context;

    /** Indicates if any settings attributes have been changed. */
    boolean m_hasChangedSettings;

    /** Value of the auto-unlock option from the configuration. */
    private boolean m_autoUnlock;

    /** The available locales. */
    private Map<String, String> m_availableLocales;

    /** The form editing base panel. */
    private FlowPanel m_basePanel;

    /** The cancel button. */
    private CmsPushButton m_cancelButton;

    /** The id's of the changed entities. */
    private Set<String> m_changedEntityIds;

    /** Changed scopes which still haven't been sent to the editor change handlers. */
    private Set<String> m_changedScopes = new HashSet<String>();

    /** The window closing handler registration. */
    private HandlerRegistration m_closingHandlerRegistration;

    /** The content info panel. */
    private CmsInfoHeader m_contentInfoHeader;

    /** The locales present within the edited content. */
    private Set<String> m_contentLocales;

    /** The copy locale button. */
    private CmsPushButton m_copyLocaleButton;

    /** The loaded content definitions by locale. */
    private Map<String, CmsContentDefinition> m_definitions;

    /** The entities to delete. */
    private Set<String> m_deletedEntities;

    /** The delete locale button. */
    private CmsPushButton m_deleteLocaleButton;

    /** Flag indicating the resource needs to removed on cancel. */
    private boolean m_deleteOnCancel;

    /** The entity value change handler calling configured editor change handlers. */
    private EditorChangeHandler m_editorChangeHandler;

    /** The entity observer instance. */
    private CmsEntityObserver m_entityObserver;

    /** Flag, indicating if save is enabled */
    private boolean m_hasChanges;

    /** Flag, indicating if there are errors */
    private boolean m_hasErrors;

    /** Flag, indicating if there are warnings */
    private boolean m_hasWarnings;

    /** The hide help bubbles button. */
    private CmsToggleButton m_hideHelpBubblesButton;

    /** The resource icon classes. */
    private String m_iconClasses;

    /** Flag which indicate whether the directedit parameter was set to true when loading the editor. */
    private boolean m_isDirectEdit;

    /** Flag, indicating if save is enabled */
    private boolean m_isSaveDisabled;

    /** Flag indicating the editor was opened as the stand alone version, not from within any other module. */
    private boolean m_isStandAlone;

    /** The locale select box. */
    private CmsSelectBox m_localeSelect;

    /** The open form button. */
    private CmsPushButton m_openFormButton;

    /** The page info panel. */
    private CmsInfoHeader m_pageInfoHeader;

    /** The event preview handler registration. */
    private HandlerRegistration m_previewHandlerRegistration;

    /** The publish button. */
    private CmsPushButton m_publishButton;

    /** The redo button. */
    private CmsPushButton m_redoButton;

    /** The registered entity id's. */
    private Set<String> m_registeredEntities;

    /** The resource type name. */
    private String m_resourceTypeName;

    /** The save button. */
    private CmsPushButton m_saveButton;

    /** The save and exit button. */
    private CmsPushButton m_saveExitButton;

    /** The content service. */
    private I_CmsContentServiceAsync m_service;

    /** The resource site path. */
    private String m_sitePath;

    /** The tab informations for this form. */
    private List<CmsTabInfo> m_tabInfos;

    /** The resource title. */
    private String m_title;

    /** The undo button. */
    private CmsPushButton m_undoButton;

    /** The undo redo event handler registration. */
    private HandlerRegistration m_undoRedoHandlerRegistration;

    /**
     * Constructor.<p>
     */
    private CmsContentEditor() {

        super((I_CmsContentServiceAsync)GWT.create(I_CmsContentService.class), new CmsDefaultWidgetService());
        m_service = (I_CmsContentServiceAsync)super.getService();
        String serviceUrl = CmsCoreProvider.get().link("org.opencms.ade.contenteditor.CmsContentService.gwt");
        ((ServiceDefTarget)m_service).setServiceEntryPoint(serviceUrl);
        getWidgetService().setWidgetFactories(WidgetRegistry.getInstance().getWidgetFactories());
        for (I_CmsEntityRenderer renderer : WidgetRegistry.getInstance().getRenderers()) {
            getWidgetService().addRenderer(renderer);
        }
        // set the acacia editor message bundle
        setDictionary(Messages.get().getDictionary());
        I_CmsLayoutBundle.INSTANCE.editorCss().ensureInjected();
        m_changedEntityIds = new HashSet<String>();
        m_registeredEntities = new HashSet<String>();
        m_availableLocales = new LinkedHashMap<String, String>();
        m_contentLocales = new HashSet<String>();
        m_deletedEntities = new HashSet<String>();
        m_definitions = new HashMap<String, CmsContentDefinition>();
        addValidationChangeHandler(new ValueChangeHandler<CmsValidationContext>() {

            public void onValueChange(ValueChangeEvent<CmsValidationContext> event) {

                handleValidationChange(event.getValue());
            }
        });
    }

    /**
     * Adds an entity change listener.<p>
     *
     * @param changeListener the change listener
     * @param changeScope the change scope
     */
    public static void addEntityChangeListener(I_CmsEntityChangeListener changeListener, String changeScope) {

        CmsDebugLog.getInstance().printLine("trying to ad change listener for scope: " + changeScope);
        if ((INSTANCE == null) || (INSTANCE.m_entityObserver == null)) {
            CmsDebugLog.getInstance().printLine("handling external registration");
            if (isObserverExported()) {
                CmsDebugLog.getInstance().printLine("registration is available");
                try {
                    addNativeListener(changeListener, changeScope);
                } catch (Exception e) {

                    CmsDebugLog.getInstance().printLine(
                        "Exception occured during listener registration" + e.getMessage());
                }
            } else {
                throw new RuntimeException("Editor is not initialized yet.");
            }
        } else {
            INSTANCE.m_entityObserver.addEntityChangeListener(changeListener, changeScope);
        }
    }

    /**
     * Gets the client id for the editable element.<p>
     *
     * @param editableData the editable element
     *
     * @return the client id for the editable element
     */
    public static String getClientIdForEditable(final I_CmsEditableData editableData) {

        return ((editableData.getElementName() != null)
            && editableData.getElementName().startsWith(editableData.getStructureId().toString()))
            ? editableData.getElementName()
            : editableData.getStructureId().toString();
    }

    /**
     * Returns the currently edited entity.<p>
     *
     * @return the currently edited entity
     */
    public static CmsEntity getEntity() {

        if ((INSTANCE == null) || (INSTANCE.m_entityObserver == null)) {
            CmsDebugLog.getInstance().printLine("handling external registration");
            if (isObserverExported()) {
                return CmsEntityBackend.createFromNativeWrapper(nativeGetEntity());
            } else {
                throw new RuntimeException("Editor is not initialized yet.");
            }
        } else {
            return INSTANCE.getCurrentEntity();
        }
    }

    /**
     * Returns the in-line editor instance.<p>
     *
     * @return the in-line editor instance
     */
    public static CmsContentEditor getInstance() {

        if (INSTANCE == null) {
            INSTANCE = new CmsContentEditor();
        }
        return INSTANCE;
    }

    /**
     * Returns if the given element or it's descendants are inline editable.<p>
     *
     * @param element the element
     *
     * @return <code>true</code> if the element has editable descendants
     */
    public static boolean hasEditable(Element element) {

        NodeList<Element> children = CmsDomUtil.querySelectorAll(FIELD_SELECTOR, element);
        return (children != null) && (children.getLength() > 0);
    }

    /**
     * Checks whether the given element is annotated for inline editing.<p>
     *
     * @param element the element to check
     *
     * @return <code>true</code> if the given element is annotated for inline editing
     */
    public static boolean isEditable(Element element) {

        String field = element.getAttribute(CmsGwtConstants.ATTR_DATA_FIELD);
        return (field != null) && field.contains("opencms://");
    }

    /**
     * Replaces the id's within data-oc-id attributes of the given element and all it's children.<p>
     *
     * @param element the element
     * @param oldId the old id
     * @param newId the new id
     */
    public static void replaceResourceIds(Element element, String oldId, String newId) {

        NodeList<Element> children = CmsDomUtil.querySelectorAll(
            FIELD_SELECTOR + ENTITY_ID_SELECTOR_PREFIX + oldId + ENTITY_ID_SELECTOR_SUFFIX,
            element);
        if (children.getLength() > 0) {
            for (int i = 0; i < children.getLength(); i++) {
                Element child = children.getItem(i);
                String idData = child.getAttribute(CmsGwtConstants.ATTR_DATA_ID);
                idData = idData.replace(oldId, newId);
                child.setAttribute(CmsGwtConstants.ATTR_DATA_ID, idData);
            }
        }
    }

    /**
     * Sets all annotated child elements editable.<p>
     *
     * @param element the element
     * @param serverId the editable resource structure id
     * @param editable <code>true</code> to enable editing
     *
     * @return <code>true</code> if the element had editable elements
     */
    public static boolean setEditable(Element element, String serverId, boolean editable) {

        I_CmsLayoutBundle.INSTANCE.editorCss().ensureInjected();
        NodeList<Element> children = CmsDomUtil.querySelectorAll(
            FIELD_SELECTOR + ENTITY_ID_SELECTOR_PREFIX + serverId + ENTITY_ID_SELECTOR_SUFFIX,
            element);
        if (children.getLength() > 0) {
            for (int i = 0; i < children.getLength(); i++) {
                Element child = children.getItem(i);
                if (editable) {
                    child.addClassName(I_CmsLayoutBundle.INSTANCE.editorCss().inlineEditable());
                } else {
                    child.removeClassName(I_CmsLayoutBundle.INSTANCE.editorCss().inlineEditable());
                }
            }
            return true;
        }
        return false;
    }

    /**
     * Adds the change listener.<p>
     *
     * @param changeListener the change listener
     * @param changeScope the change scope
     */
    static native void addNativeListener(I_CmsEntityChangeListener changeListener, String changeScope)/*-{
        var instance = changeListener;
        var nat = {
            onChange : function(entity) {
                var cmsEntity = @org.opencms.acacia.client.entity.CmsEntityBackend::createFromNativeWrapper(Lcom/google/gwt/core/client/JavaScriptObject;)(entity);
                instance.@org.opencms.ade.contenteditor.client.I_CmsEntityChangeListener::onEntityChange(Lorg/opencms/acacia/shared/CmsEntity;)(cmsEntity);
            }
        }
        var method = $wnd[@org.opencms.ade.contenteditor.client.CmsContentEditor::ADD_CHANGE_LISTENER_METHOD];
        if (typeof method == 'function') {
            method(nat, changeScope);
        }
    }-*/;

    /**
     * Checks whether the add entity change listener method has been exported.<p>
     *
     * @return <code>true</code> if the add entity change listener method has been exported
     */
    private static native boolean isObserverExported()/*-{
        var method = $wnd[@org.opencms.ade.contenteditor.client.CmsContentEditor::ADD_CHANGE_LISTENER_METHOD];
        if (typeof method == 'function') {
            return true;
        } else {
            return false;
        }
    }-*/;

    /**
     * Returns the current entity.<p>
     *
     * @return the current entity
     */
    private static native JavaScriptObject nativeGetEntity()/*-{
        return $wnd[@org.opencms.ade.contenteditor.client.CmsContentEditor::GET_CURRENT_ENTITY_METHOD]
                ();
    }-*/;

    /**
     * Closes the editor.<p>
     * May be used from outside the editor module.<p>
     */
    public void closeEditor() {

        if (m_saveButton != null) {
            if (m_saveButton.isEnabled()) {
                CmsConfirmDialog dialog = new CmsConfirmDialog(
                    org.opencms.gwt.client.Messages.get().key(org.opencms.gwt.client.Messages.GUI_DIALOG_RESET_TITLE_0),
                    Messages.get().key(Messages.GUI_CONFIRM_LEAVING_EDITOR_0));
                dialog.setHandler(new I_CmsConfirmDialogHandler() {

                    public void onClose() {

                        cancelEdit();
                    }

                    public void onOk() {

                        saveAndExit();
                    }
                });
                dialog.center();
            } else {
                cancelEdit();
            }
        }
    }

    /**
     * Bypasses a focus bug in IE which can happen if the user opens the HTML code editor from the WYSIWYG editor.<p>
     *
     * The next time they open the editor form from the same container page, the user may be unable to focus on any input
     * fields. To prevent this, we create a dummy input field outside the visible screen region and focus it when opening
     * the editor.
     */
    public void fixFocus() {

        TextBox invisibleTextBox = new TextBox();
        Style style = invisibleTextBox.getElement().getStyle();
        style.setPosition(Position.FIXED);
        style.setLeft(-99999, Unit.PX);
        style.setTop(-99999, Unit.PX);
        m_basePanel.add(invisibleTextBox);
        // base panel is already attached at this point, so we can just set the focus
        invisibleTextBox.setFocus(true);
    }

    /**
     * @see org.opencms.acacia.client.CmsEditorBase#getService()
     */
    @Override
    public I_CmsContentServiceAsync getService() {

        return m_service;
    }

    /**
     * Loads the content definition for the given entity and executes the callback on success.<p>
     *
     * @param entityId the entity id
     * @param editedEntity the currently edited entity
     * @param callback the callback
     */
    public void loadDefinition(
        final String entityId,
        final CmsEntity editedEntity,
        final I_CmsSimpleCallback<CmsContentDefinition> callback) {

        CmsRpcAction<CmsContentDefinition> action = new CmsRpcAction<CmsContentDefinition>() {

            @Override
            public void execute() {

                start(0, true);
                getService().loadDefinition(
                    entityId,
                    m_clientId,
                    editedEntity,
                    getSkipPaths(),
                    m_context.getSettingPresets(),
                    this);
            }

            @Override
            protected void onResponse(final CmsContentDefinition result) {

                registerContentDefinition(result);
                WidgetRegistry.getInstance().registerExternalWidgets(
                    result.getExternalWidgetConfigurations(),
                    new Command() {

                        public void execute() {

                            stop(false);
                            callback.execute(result);
                        }
                    });
            }
        };
        action.execute();
    }

    /**
     * Loads the content definition for the given entity and executes the callback on success.<p>
     *
     * @param entityId the entity id
     * @param newLink the new link
     * @param modelFileId  the model file id
     * @param postCreateHandler the post-create handler class name (optional)
     * @param mode the content creation mode
     * @param mainLocale the main language to copy in case the element language node does not exist yet
     * @param editHandlerData the data for the edit handler, if one is used to create a new content; null otherwise
     * @param settingPresets the presets for container element settings
     * @param editorStylesheet the path for the editor style sheet (may be null)
     * @param callback the callback
     */
    public void loadInitialDefinition(
        final String entityId,
        final String newLink,
        final CmsUUID modelFileId,
        final String postCreateHandler,
        final String mode,
        final String mainLocale,
        final CmsEditHandlerData editHandlerData,
        Map<String, String> settingPresets,
        String editorStylesheet,
        final I_CmsSimpleCallback<CmsContentDefinition> callback) {

        CmsRpcAction<CmsContentDefinition> action = new CmsRpcAction<CmsContentDefinition>() {

            @Override
            public void execute() {

                start(0, true);
                getService().loadInitialDefinition(
                    entityId,
                    m_clientId,
                    newLink,
                    modelFileId,
                    CmsCoreProvider.get().getUri(),
                    mainLocale,
                    postCreateHandler,
                    mode,
                    editHandlerData,
                    settingPresets,
                    editorStylesheet,
                    this);
            }

            @Override
            protected void onResponse(final CmsContentDefinition result) {

                if (result.isModelInfo()) {
                    stop(false);
                    callback.execute(result);
                } else {
                    registerContentDefinition(result);
                    WidgetRegistry.getInstance().registerExternalWidgets(
                        result.getExternalWidgetConfigurations(),
                        new Command() {

                            public void execute() {

                                stop(false);
                                callback.execute(result);
                            }
                        });
                }
            }
        };
        action.execute();
    }

    /**
     * Loads the content definition for the given entity and executes the callback on success.<p>
     *
     * @param entityId the entity id
     * @param editedEntity the currently edited entity
     * @param callback the callback
     */
    public void loadNewDefinition(
        final String entityId,
        final CmsEntity editedEntity,
        final I_CmsSimpleCallback<CmsContentDefinition> callback) {

        final Map<String, String> presets = new HashMap<>();
        if ((m_context != null) && (m_context.getSettingPresets() != null)) {
            presets.putAll(m_context.getSettingPresets());
        }
        CmsRpcAction<CmsContentDefinition> action = new CmsRpcAction<CmsContentDefinition>() {

            @Override
            public void execute() {

                start(0, true);
                getService().loadNewDefinition(entityId, m_clientId, editedEntity, getSkipPaths(), presets, this);
            }

            @Override
            protected void onResponse(final CmsContentDefinition result) {

                registerContentDefinition(result);
                WidgetRegistry.getInstance().registerExternalWidgets(
                    result.getExternalWidgetConfigurations(),
                    new Command() {

                        public void execute() {

                            stop(false);
                            callback.execute(result);
                        }
                    });
            }
        };
        action.execute();
    }

    /**
     * Opens the content editor dialog.<p>
     *
     * @param context the editor context
     * @param locale the content locale
     * @param elementId the element id
     * @param clientId the container element client id if available
     * @param newLink the new link
     * @param modelFileId the model file id
     * @param postCreateHandler the post-create handler class (optional)
     * @param mode the content creation mode
     * @param mainLocale the main language to copy in case the element language node does not exist yet
     * @param editHandlerData the edit handler data, if we are using an edit handler to create a new element; null otherwise
     * @param onClose the command executed on dialog close
     */
    public void openFormEditor(
        final CmsEditorContext context,
        final String locale,
        String elementId,
        String clientId,
        final String newLink,
        final CmsUUID modelFileId,
        final String postCreateHandler,
        final String mode,
        final String mainLocale,
        final CmsEditHandlerData editHandlerData,
        final I_CmsEditorCloseHandler onClose) {

        m_onClose = onClose;
        m_clientId = clientId;
        initEventPreviewHandler();
        final CmsUUID structureId = new CmsUUID(elementId);
        m_context = context;

        I_CmsSimpleCallback<Boolean> callback = new I_CmsSimpleCallback<Boolean>() {

            public void execute(Boolean arg) {

                if (arg.booleanValue()) {
                    loadInitialDefinition(
                        CmsContentDefinition.uuidToEntityId(structureId, locale),
                        newLink,
                        modelFileId,
                        mode,
                        postCreateHandler,
                        mainLocale,
                        editHandlerData,
                        context.getSettingPresets(),
                        context.getEditorStylesheet(),
                        new I_CmsSimpleCallback<CmsContentDefinition>() {

                            public void execute(CmsContentDefinition contentDefinition) {

                                if (contentDefinition.isModelInfo()) {
                                    openModelSelectDialog(context, contentDefinition);
                                } else {
                                    initEditor(context, contentDefinition, null, false, null);
                                }
                            }
                        });
                } else {
                    showLockedResourceMessage();
                }

            }
        };
        // make sure the resource is locked, if we are not creating a new one
        if (CmsStringUtil.isNotEmptyOrWhitespaceOnly(newLink)) {
            callback.execute(Boolean.TRUE);
        } else {
            CmsCoreProvider.get().lock(structureId, callback);
        }
    }

    /**
     * Renders the in-line editor for the given element.<p>
     *
     * @param context the editor context
     * @param elementId the element id
     * @param locale the content locale
     * @param panel the element panel
     * @param mainLocale the main language to copy in case the element language node does not exist yet
     * @param loadTime the time when the requested resource was loaded
     * @param onClose the command to execute on close
     */
    public void openInlineEditor(
        final CmsEditorContext context,
        CmsUUID elementId,
        String locale,
        final I_CmsInlineFormParent panel,
        final String mainLocale,
        long loadTime,
        I_CmsEditorCloseHandler onClose) {

        initEventPreviewHandler();
        m_context = context;
        final String entityId = CmsContentDefinition.uuidToEntityId(elementId, locale);
        internalSetLocale(locale);
        m_onClose = onClose;
        CmsCoreProvider.get().lock(elementId, loadTime, new I_CmsSimpleCallback<Boolean>() {

            public void execute(Boolean arg) {

                if (arg.booleanValue()) {
                    loadInitialDefinition(
                        entityId,
                        null,
                        null,
                        null,
                        null,
                        mainLocale,
                        null,
                        Collections.emptyMap(),
                        context.getEditorStylesheet(),
                        new I_CmsSimpleCallback<CmsContentDefinition>() {

                            public void execute(CmsContentDefinition contentDefinition) {

                                initEditor(context, contentDefinition, panel, true, mainLocale);
                            }
                        });
                } else {
                    showLockedResourceMessage();
                }
            }
        });
    }

    /**
     * Opens the form based editor. Used within the stand alone acacia/editor.jsp.<p>
     *
     * @param context the editor context
     */
    public void openStandAloneFormEditor(final CmsEditorContext context) {

        initEventPreviewHandler();
        final CmsContentDefinition definition;
        try {
            definition = (CmsContentDefinition)CmsRpcPrefetcher.getSerializedObjectFromDictionary(
                getService(),
                I_CmsContentService.DICT_CONTENT_DEFINITION);
        } catch (SerializationException e) {
            RootPanel.get().add(new Label(e.getMessage()));
            return;
        }
        context.setReusedElement(definition.isReusedElement());
        m_isStandAlone = true;
        if (definition.isModelInfo()) {
            openModelSelectDialog(context, definition);
        } else {
            CmsCoreProvider.get().lock(
                CmsContentDefinition.entityIdToUuid(definition.getEntityId()),
                new I_CmsSimpleCallback<Boolean>() {

                    public void execute(Boolean arg) {

                        if (arg.booleanValue()) {

                            registerContentDefinition(definition);
                            // register all external widgets
                            WidgetRegistry.getInstance().registerExternalWidgets(
                                definition.getExternalWidgetConfigurations(),
                                new Command() {

                                    public void execute() {

                                        initEditor(context, definition, null, false, null);
                                    }
                                });

                        } else {
                            showLockedResourceMessage();
                        }
                    }
                });
        }
    }

    /**
     * Registers a deep copy of the source entity with the given target entity id.<p>
     *
     * @param sourceEntityId the source entity id
     * @param targetEntityId the target entity id
     */
    public void registerClonedEntity(String sourceEntityId, String targetEntityId) {

        CmsEntityBackend.getInstance().getEntity(sourceEntityId).createDeepCopy(targetEntityId);
    }

    /**
     * Registers the given content definition.<p>
     *
     * @param definition the content definition
     */
    public void registerContentDefinition(CmsContentDefinition definition) {

        getWidgetService().addConfigurations(definition.getConfigurations());
        CmsType baseType = definition.getTypes().get(definition.getEntityTypeName());
        m_entityBackend.registerTypes(baseType, definition.getTypes());
        for (CmsEntity entity : definition.getEntities().values()) {
            CmsEntity previousValue = m_entityBackend.getEntity(entity.getId());
            if (previousValue != null) {
                m_entityBackend.changeEntityContentValues(previousValue, entity);
            } else {
                m_entityBackend.registerEntity(entity);
                m_registeredEntities.add(entity.getId());
            }
        }
        for (Map.Entry<String, CmsComplexWidgetData> entry : definition.getComplexWidgetData().entrySet()) {
            String attrName = entry.getKey();
            CmsComplexWidgetData widgetData = entry.getValue();
            getWidgetService().registerComplexWidgetAttribute(
                attrName,
                widgetData.getRendererName(),
                widgetData.getConfiguration());
        }
    }

    /**
     * Saves the given entities.<p>
     *
     * @param clearOnSuccess <code>true</code> to clear the VIE instance on success
     * @param callback the call back command
     */
    public void saveAndDeleteEntities(final boolean clearOnSuccess, final I_CmsSimpleCallback<Boolean> callback) {

        final CmsEntity entity = m_entityBackend.getEntity(m_entityId);
        saveAndDeleteEntities(entity, new ArrayList<>(m_deletedEntities), clearOnSuccess, true, callback);
    }

    /**
     * Saves the given entities.<p>
     *
     * @param lastEditedEntity the last edited entity
     * @param deletedEntites the deleted entity id's
     * @param clearOnSuccess <code>true</code> to clear the VIE instance on success
     * @param failOnWarnings <code>true</code> to prevent saving when warnings exist
     * @param callback the call back command
     */
    public void saveAndDeleteEntities(
        final CmsEntity lastEditedEntity,
        final List<String> deletedEntites,
        final boolean clearOnSuccess,
        final boolean failOnWarnings,
        final I_CmsSimpleCallback<Boolean> callback) {

        CmsRpcAction<CmsSaveResult> asyncCallback = new CmsRpcAction<CmsSaveResult>() {

            @Override
            public void execute() {

                start(200, true);
                getService().saveAndDeleteEntities(
                    lastEditedEntity,
                    m_clientId,
                    deletedEntites,
                    getSkipPaths(),
                    m_locale,
                    clearOnSuccess,
                    failOnWarnings,
                    this);
            }

            @Override
            protected void onResponse(CmsSaveResult result) {

                stop(false);
                if ((result != null) && result.hasErrors()) {
                    if (failOnWarnings && !result.getValidationResult().hasErrors()) {
                        CmsContentEditor.this.showSaveValidationWarningDialog(
                            result.getIssueInformation(),
                            new I_CmsSimpleCallback<Boolean>() {

                                @Override
                                public void execute(Boolean arg) {

                                    saveAndDeleteEntities(
                                        lastEditedEntity,
                                        deletedEntites,
                                        clearOnSuccess,
                                        false,
                                        callback);
                                }
                            });
                    } else {
                        showValidationErrorDialog(result.getIssueInformation());
                    }
                } else {
                    callback.execute(Boolean.valueOf((result != null) && result.isHasChangedSettings()));
                    if (clearOnSuccess) {
                        destroyForm(true);
                    }
                }
            }
        };
        asyncCallback.execute();
    }

    /**
     * Saves a value in an Xml content.<p>
     *
     * @param contentId the structure id of the content
     * @param contentPath the xpath for which to set the value
     * @param locale the locale for which to set the value
     * @param value the new value
     * @param asyncCallback the callback for the result
     */
    public void saveValue(
        final String contentId,
        final String contentPath,
        final String locale,
        final String value,
        final AsyncCallback<String> asyncCallback) {

        CmsRpcAction<String> action = new CmsRpcAction<String>() {

            @Override
            public void execute() {

                start(0, false);
                getService().saveValue(contentId, contentPath, locale, value, this);

            }

            @Override
            protected void onResponse(String result) {

                stop(false);
                asyncCallback.onSuccess(result);

            }
        };
        action.execute();
    }

    /**
     * Sets the show editor help flag to the user session.<p>
     *
     * @param show the show editor help flag
     */
    public void setShowEditorHelp(final boolean show) {

        CmsCoreProvider.get().setShowEditorHelp(show);
    }

    /**
     * Removes the given entity from the entity VIE store.<p>
     *
     * @param entityId the entity id
     */
    public void unregistereEntity(String entityId) {

        CmsEntityBackend.getInstance().removeEntity(entityId);
    }

    /**
     * @see org.opencms.acacia.client.CmsEditorBase#clearEditor()
     */
    @Override
    protected void clearEditor() {

        super.clearEditor();
        m_context = null;
        if (m_undoRedoHandlerRegistration != null) {
            m_undoRedoHandlerRegistration.removeHandler();
        }
        if (m_toolbar != null) {
            m_toolbar.removeFromParent();
            m_toolbar = null;
        }
        m_cancelButton = null;
        m_localeSelect = null;
        m_deleteLocaleButton = null;
        m_copyLocaleButton = null;
        m_openFormButton = null;
        m_saveButton = null;
        m_onClose = null;
        internalSetLocale(null);
        if (m_basePanel != null) {
            m_basePanel.removeFromParent();
            m_basePanel = null;
        }
        if (m_entityObserver != null) {
            m_entityObserver.clear();
            m_entityObserver = null;
        }
        m_changedEntityIds.clear();
        m_registeredEntities.clear();
        m_availableLocales.clear();
        m_contentLocales.clear();
        m_deletedEntities.clear();
        m_definitions.clear();
        m_title = null;
        m_sitePath = null;
        m_resourceTypeName = null;
        if (m_closingHandlerRegistration != null) {
            m_closingHandlerRegistration.removeHandler();
            m_closingHandlerRegistration = null;
        }
        if (m_isStandAlone) {
            closeEditorWidow();
        } else {
            RootPanel.getBodyElement().getParentElement().getStyle().clearOverflow();
        }
        if (m_previewHandlerRegistration != null) {
            m_previewHandlerRegistration.removeHandler();
            m_previewHandlerRegistration = null;
        }
        CmsDomUtil.getHtmlElement().removeClassName(EDITOR_MARKER_CLASS);
    }

    /**
     * Gets the editor context.<p>
     *
     * @return the editor context
     */
    protected CmsEditorContext getContext() {

        return m_context;
    }

    /**
     * @see org.opencms.acacia.client.CmsEditorBase#getContextUri()
     */
    @Override
    protected String getContextUri() {

        return CmsCoreProvider.get().getUri();
    }

    /**
     * Gets the entity id.<p>
     *
     * @return the entity id
     */
    protected String getEntityId() {

        return m_entityId;
    }

    /**
     * @see org.opencms.acacia.client.CmsEditorBase#getHtmlContextInfo()
     */
    @Override
    protected String getHtmlContextInfo() {

        return m_context.getHtmlContextInfo();
    }

    /**
     * Returns the paths to be skipped when synchronizing locale independent fields.<p>
     *
     * @return the paths to be skipped when synchronizing locale independent fields
     */
    protected Collection<String> getSkipPaths() {

        return ((CmsDefaultWidgetService)getWidgetService()).getSkipPaths();
    }

    /**
     * Adds a content definition to the internal store.<p>
     *
     * @param definition the definition to add
     */
    void addContentDefinition(CmsContentDefinition definition) {

        m_definitions.put(definition.getLocale(), definition);
        m_contentLocales.add(definition.getLocale());
    }

    /**
     * Calls the editor change handlers.<p>
     *
     * @param changedScopes the changed content value scopes
     */
    void callEditorChangeHandlers(final Set<String> changedScopes) {

        m_changedScopes.addAll(changedScopes);
        if (!m_callingChangeHandlers && (m_changedScopes.size() > 0)) {
            m_callingChangeHandlers = true;
            final Set<String> scopesToSend = new HashSet<String>(m_changedScopes);
            m_changedScopes.clear();
            final CmsEntity entity = m_entityBackend.getEntity(m_entityId);
            final org.opencms.acacia.shared.CmsEntity currentState = entity.createDeepCopy(m_entityId);
            CmsRpcAction<CmsContentDefinition> action = new CmsRpcAction<CmsContentDefinition>() {

                @Override
                public void execute() {

                    start(200, true);
                    getService().callEditorChangeHandlers(
                        getEntityId(),
                        currentState,
                        getSkipPaths(),
                        scopesToSend,
                        this);
                }

                @Override
                public void onFailure(Throwable t) {

                    m_callingChangeHandlers = false;
                    super.onFailure(t);

                }

                @Override
                protected void onResponse(CmsContentDefinition result) {

                    m_callingChangeHandlers = false;
                    stop(false);
                    updateEditorValues(currentState, result.getEntity());
                    callEditorChangeHandlers(new HashSet<String>());
                }
            };
            action.execute();
        }
    }

    /**
     * Cancels the editing process.<p>
     */
    void cancelEdit() {

        // store the scroll position
        int scrollTop = RootPanel.getBodyElement().getOwnerDocument().getScrollTop();
        CmsContentEditorHandler.scrollPosition = Integer.valueOf(scrollTop);
        setEditorState(false);
        unlockResource();
        if (m_onClose != null) {
            m_onClose.onClose(m_hasChangedSettings, /*publishDialog=*/false);
        }
        destroyForm(true);
        clearEditor();
        // restore the scroll position
        RootPanel.getBodyElement().getOwnerDocument().setScrollTop(scrollTop);
    }

    /**
     * Checks if the content is valid and sends a notification if not.<p>
     * This will not trigger a validation run, but will use the latest state.<p>
     *
     * @return <code>true</code> in case there are no validation issues
     */
    boolean checkValidation() {

        boolean result;
        if (m_changedEntityIds.isEmpty()) {
            result = true;
        } else if (m_saveButton.isEnabled()) {
            result = true;
        } else {
            result = false;
            CmsNotification.get().send(Type.ERROR, m_saveButton.getDisabledReason());
        }
        return result;
    }

    /**
     * Asks the user to confirm resetting all changes.<p>
     */
    void confirmCancel() {

        if (m_hasChanges) {
            CmsConfirmDialog dialog = new CmsConfirmDialog(
                org.opencms.gwt.client.Messages.get().key(org.opencms.gwt.client.Messages.GUI_DIALOG_RESET_TITLE_0),
                org.opencms.gwt.client.Messages.get().key(org.opencms.gwt.client.Messages.GUI_DIALOG_RESET_TEXT_0));
            dialog.setHandler(new I_CmsConfirmDialogHandler() {

                public void onClose() {

                    // nothing to do
                }

                public void onOk() {

                    cancelEdit();
                }
            });
            dialog.center();
        } else {
            cancelEdit();
        }
    }

    /**
     * Opens the confirm delete locale dialog.<p>
     */
    void confirmDeleteLocale() {

        CmsConfirmDialog dialog = new CmsConfirmDialog(
            Messages.get().key(Messages.GUI_CONFIRM_DELETE_LOCALE_TITLE_0),
            Messages.get().key(Messages.GUI_CONFIRM_DELETE_LOCALE_TEXT_0));
        dialog.setHandler(new I_CmsConfirmDialogHandler() {

            public void onClose() {

                // nothing to do
            }

            public void onOk() {

                deleteCurrentLocale();
            }
        });
        dialog.center();
    }

    /**
     * Copies the current entity values to the given locales.<p>
     *
     * @param targetLocales the target locales
     */
    void copyLocales(final Set<String> targetLocales) {

        final CmsEntity entity = m_entityBackend.getEntity(m_entityId);
        CmsRpcAction<Void> action = new CmsRpcAction<Void>() {

            @Override
            public void execute() {

                start(200, true);
                getService().copyLocale(targetLocales, entity, this);
            }

            @Override
            protected void onResponse(Void result) {

                stop(false);
            }
        };
        action.execute();
        for (String targetLocale : targetLocales) {
            String targetId = getIdForLocale(targetLocale);
            if (!m_entityId.equals(targetId)) {
                if (m_registeredEntities.contains(targetId)) {
                    unregistereEntity(targetId);
                }
                registerClonedEntity(m_entityId, targetId);
                m_registeredEntities.add(targetId);
                m_changedEntityIds.add(targetId);
                m_contentLocales.add(targetLocale);
                m_deletedEntities.remove(targetId);
                m_hasChanges = true;
                enableSave();
            }
        }
        updateValidation();
        initLocaleSelect();
    }

    /**
     * Deferrers the save action to the end of the browser event queue.<p>
     */
    void deferSave() {

        Scheduler.get().scheduleDeferred(new ScheduledCommand() {

            public void execute() {

                save();
            }
        });
    }

    /**
     * Deferrers the save and exit action to the end of the browser event queue.<p>
     */
    void deferSaveAndExit() {

        Scheduler.get().scheduleDeferred(new ScheduledCommand() {

            public void execute() {

                saveAndExit();
            }
        });
    }

    /**
     * Deletes the current locale.<p>
     */
    void deleteCurrentLocale() {

        // there has to remain at least one content locale
        if (m_contentLocales.size() > 1) {
            String deletedLocale = m_locale;
            m_contentLocales.remove(deletedLocale);
            m_registeredEntities.remove(m_entityId);
            m_changedEntityIds.remove(m_entityId);
            m_deletedEntities.add(m_entityId);
            getValidationHandler().getValidationContext().removeEntityId(m_entityId);
            unregistereEntity(m_entityId);
            m_hasChanges = true;
            enableSave();
            String nextLocale = null;
            if (m_registeredEntities.isEmpty()) {
                nextLocale = m_contentLocales.iterator().next();
            } else {
                nextLocale = CmsContentDefinition.getLocaleFromId(m_registeredEntities.iterator().next());
            }
            switchLocale(nextLocale);
        }
    }

    /**
     * Disables the save buttons with the given message.<p>
     *
     * @param message the disabled message
     */
    void disableSave(String message) {

        // If there are warnings or errors, we keep the buttons enabled
        // to display a hint dialog on the warnings/errors on click.
        if (!(m_hasWarnings || m_hasErrors)) {
            m_saveButton.disable(message);
            m_saveExitButton.disable(message);
            m_isSaveDisabled = true;
        }
    }

    /**
     * Leaves the editor saving the content if necessary.<p>
     */
    void exitWithSaving() {

        if (checkValidation()) {
            if (m_saveExitButton.isEnabled()) {
                saveAndExit();
            } else {
                cancelEdit();
            }
        }
    }

    /**
     * Handles validation changes.<p>
     *
     * @param validationContext the changed validation context
     */
    void handleValidationChange(CmsValidationContext validationContext) {

        // adjust the css classes for the save buttons depending on the validation info.
        updateSaveButtons(validationContext.hasValidationErrors(), validationContext.hasValidationWarnings());
    }

    /**
     * Hides the editor help bubbles.<p>
     *
     * @param hide <code>true</code> to hide the help bubbles
     */
    void hideHelpBubbles(boolean hide) {

        setShowEditorHelp(!hide);
        CmsValueFocusHandler.getInstance().hideHelpBubbles(RootPanel.get(), hide);
        if (!hide) {
            m_hideHelpBubblesButton.setTitle(Messages.get().key(Messages.GUI_TOOLBAR_HELP_BUBBLES_SHOWN_0));
        } else {
            m_hideHelpBubblesButton.setTitle(Messages.get().key(Messages.GUI_TOOLBAR_HELP_BUBBLES_HIDDEN_0));
        }
    }

    /**
     * Initializes the editor.<p>
     *
     * @param context the editor context
     * @param contentDefinition the content definition
     * @param formParent the inline form parent panel, used for inline editing only
     * @param inline <code>true</code> to render the editor for inline editing
     * @param mainLocale the main language to copy in case the element language node does not exist yet
     */
    void initEditor(
        CmsEditorContext context,
        CmsContentDefinition contentDefinition,
        I_CmsInlineFormParent formParent,
        boolean inline,
        String mainLocale) {

        m_context = context;
        internalSetLocale(contentDefinition.getLocale());
        m_entityId = contentDefinition.getEntityId();
        m_deleteOnCancel = contentDefinition.isDeleteOnCancel();
        m_autoUnlock = contentDefinition.isAutoUnlock();
        m_isDirectEdit = contentDefinition.isDirectEdit();
        CmsDomUtil.getHtmlElement().addClassName(EDITOR_MARKER_CLASS);

        initClosingHandler();
        setContentDefinition(contentDefinition);
        initToolbar(inline);
        updateValidation();
        if (inline && (formParent != null)) {
            if ((mainLocale != null)
                && (CmsDomUtil.querySelector(
                    "[" + CmsGwtConstants.ATTR_DATA_ID + "^='" + m_entityId + "']",
                    formParent.getElement()) == null)) {
                // in case a main locale is given and there are not any HTML elements attributed to the current entity id,
                // check if the content was rendered for the main locale
                CmsUUID structureId = CmsContentDefinition.entityIdToUuid(m_entityId);
                String mainLocaleEntityId = CmsContentDefinition.uuidToEntityId(structureId, mainLocale);
                NodeList<Element> elements = CmsDomUtil.querySelectorAll(
                    "[" + CmsGwtConstants.ATTR_DATA_ID + "^='" + mainLocaleEntityId + "']",
                    formParent.getElement());
                if (elements.getLength() > 0) {
                    for (int i = 0; i < elements.getLength(); i++) {
                        Element element = elements.getItem(i);
                        element.setAttribute(
                            CmsGwtConstants.ATTR_DATA_ID,
                            element.getAttribute(CmsGwtConstants.ATTR_DATA_ID).replace(mainLocaleEntityId, m_entityId));
                    }
                }

            }
            initEditOverlay(formParent.getElement());
            addOverlayClickHandler(new ClickHandler() {

                public void onClick(ClickEvent event) {

                    exitWithSaving();
                }
            });
            m_hideHelpBubblesButton.setVisible(false);
            setNativeResourceInfo(m_sitePath, m_locale);
            initEntityObserver();
            if (m_definitions.get(m_locale).hasEditorChangeHandlers()) {
                initEditorChangeHandlers(m_definitions.get(m_locale).getEditorChangeScopes());
            }
            renderInlineEntity(m_entityId, formParent);
        } else {
            initFormPanel();
            renderFormContent();
            fixFocus();
        }
        getValidationHandler().setSynchronizedValues(m_definitions.get(m_locale).getSynchronizations());
        if (contentDefinition.isPerformedAutocorrection()) {
            CmsNotification.get().send(
                CmsNotification.Type.NORMAL,
                Messages.get().key(Messages.GUI_WARN_INVALID_XML_STRUCTURE_0));
            setChanged();
        }
    }

    /**
     * Initializes the editor change handler.<p>
     *
     * @param changeScopes the scopes to watch for changes
     */
    void initEditorChangeHandlers(Collection<String> changeScopes) {

        if (m_editorChangeHandler != null) {
            m_editorChangeHandler.clear();
        }
        m_editorChangeHandler = new EditorChangeHandler(getEntity(), changeScopes);
    }

    /**
     * Initializes the entity observer.<p>
     */
    void initEntityObserver() {

        if (m_entityObserver != null) {
            m_entityObserver.clear();
        }
        m_entityObserver = new CmsEntityObserver(getCurrentEntity());
        exportObserver();
    }

    /**
     * Opens the form based editor.<p>
     */
    void initFormPanel() {

        removeEditOverlays();
        m_openFormButton.setVisible(false);
        m_saveButton.setVisible(true);
        m_hideHelpBubblesButton.setVisible(true);
        m_undoButton.setVisible(true);
        m_redoButton.setVisible(true);
        m_basePanel = new FlowPanel();
        m_basePanel.addStyleName(I_CmsLayoutBundle.INSTANCE.editorCss().basePanel());
        m_basePanel.addStyleName(I_CmsLayoutBundle.INSTANCE.generalCss().opencms());
        // insert base panel before the tool bar to keep the tool bar visible
        RootPanel.get().add(m_basePanel);
        if (m_isStandAlone) {
            RootPanel.getBodyElement().addClassName(I_CmsLayoutBundle.INSTANCE.editorCss().standAloneEditor());
        } else {
            RootPanel.getBodyElement().getParentElement().getStyle().setOverflow(Overflow.HIDDEN);
        }
    }

    /**
     * Opens the copy locale dialog.<p>
     */
    void openCopyLocaleDialog() {

        CmsCopyLocaleDialog dialog = new CmsCopyLocaleDialog(
            m_availableLocales,
            m_contentLocales,
            m_locale,
            m_definitions.get(m_locale).hasSynchronizedElements(),
            this);
        dialog.center();
    }

    /**
     * Opens the model file select dialog.<p>
     *
     * @param context the editor context
     * @param definition the content definition
     */
    void openModelSelectDialog(final CmsEditorContext context, final CmsContentDefinition definition) {

        I_CmsModelSelectHandler handler = new I_CmsModelSelectHandler() {

            public void onModelSelect(CmsUUID modelStructureId) {

                if (modelStructureId == null) {
                    modelStructureId = CmsUUID.getNullUUID();
                }
                openFormEditor(
                    context,
                    definition.getLocale(),
                    definition.getReferenceResourceId().toString(),
                    m_clientId,
                    definition.getNewLink(),
                    modelStructureId,
                    null,
                    null,
                    null,

                    null,
                    m_onClose);
            }
        };
        String title = org.opencms.gwt.client.Messages.get().key(
            org.opencms.gwt.client.Messages.GUI_MODEL_SELECT_TITLE_0);
        String message = org.opencms.gwt.client.Messages.get().key(
            org.opencms.gwt.client.Messages.GUI_MODEL_SELECT_MESSAGE_0);
        CmsModelSelectDialog dialog = new CmsModelSelectDialog(handler, definition.getModelInfos(), title, message);
        dialog.center();
    }

    /**
     * Previews the native event to enable keyboard short cuts.<p>
     *
     * @param event the event
     */
    void previewNativeEvent(NativePreviewEvent event) {

        Event nativeEvent = Event.as(event.getNativeEvent());
        if (event.getTypeInt() == Event.ONKEYDOWN) {
            int keyCode = nativeEvent.getKeyCode();
            if (nativeEvent.getCtrlKey() || nativeEvent.getMetaKey()) {
                // look for short cuts
                if (nativeEvent.getShiftKey()) {
                    if (keyCode == KeyCodes.KEY_S) {

                        exitWithSaving();
                        nativeEvent.preventDefault();
                        nativeEvent.stopPropagation();
                    } else if (keyCode == KeyCodes.KEY_X) {
                        confirmCancel();
                        nativeEvent.preventDefault();
                        nativeEvent.stopPropagation();
                    }
                } else if (keyCode == KeyCodes.KEY_S) {
                    if (checkValidation()) {
                        save();
                    }
                    nativeEvent.preventDefault();
                    nativeEvent.stopPropagation();
                }

            }
        }
    }

    /**
     * Renders the form content.<p>
     */
    void renderFormContent() {

        m_contentInfoHeader = new CmsInfoHeader(m_title, null, m_sitePath, m_locale, m_iconClasses);
        initLocaleSelect();
        setNativeResourceInfo(m_sitePath, m_locale);

        m_basePanel.add(m_contentInfoHeader);
        if (m_context.isReusedElement()) {
            String message = Messages.get().key(Messages.GUI_CONTENT_EDITOR_REUSE_MARKER_0);
            Label label = new Label(message);
            label.addStyleName("oc-editor-reuse-marker");
            m_contentInfoHeader.addWidget(label);
        }
        FlowPanel localeButtons = m_contentInfoHeader.getPathButtons();
        localeButtons.addStyleName(I_CmsLayoutBundle.INSTANCE.editorCss().localeButtons());
        SimplePanel content = new SimplePanel();
        content.setStyleName(org.opencms.acacia.client.css.I_CmsLayoutBundle.INSTANCE.form().formParent());
        m_basePanel.add(content);
        initEntityObserver();
        if (m_definitions.get(m_locale).hasEditorChangeHandlers()) {
            initEditorChangeHandlers(m_definitions.get(m_locale).getEditorChangeScopes());
        }
        renderEntityForm(m_entityId, m_tabInfos, content, m_basePanel.getElement());
        if ((m_clientId != null) && (getFormTabs() != null)) {

            CmsListInfoBean pageInfo = CmsContainerpageController.get().getData().getPageInfo();
            m_pageInfoHeader = new CmsInfoHeader(
                pageInfo.getTitle(),
                null,
                pageInfo.getSubTitle(),
                CmsContainerpageController.get().getData().getLocale(),
                pageInfo.getBigIconClasses());
            updateInfoHeader(CmsContentDefinition.SETTINGS_TAB_ID.equals(getFormTabs().getSelectedId()));
            getFormTabs().addSelectionHandler(new SelectionHandler<Integer>() {

                public void onSelection(SelectionEvent<Integer> event) {

                    updateInfoHeader(CmsContentDefinition.SETTINGS_TAB_ID.equals(getFormTabs().getSelectedId()));
                }
            });
        }
    }

    /**
     * Saves the content and closes the editor.<p>
     */
    void save() {

        saveAndDeleteEntities(false, new I_CmsSimpleCallback<Boolean>() {

            public void execute(Boolean hasChangedSettings) {

                setSaved();
                setUnchanged();
                m_hasChangedSettings = m_hasChangedSettings || hasChangedSettings.booleanValue();
            }
        });
    }

    /**
     * Saves the content and closes the editor.<p>
     */
    void saveAndExit() {

        boolean unlock = shouldUnlockAutomatically();
        // store the scroll position
        final int scrollTop = RootPanel.getBodyElement().getOwnerDocument().getScrollTop();
        CmsContentEditorHandler.scrollPosition = Integer.valueOf(scrollTop);
        saveAndDeleteEntities(unlock, new I_CmsSimpleCallback<Boolean>() {

            public void execute(final Boolean hasChangedSettings) {

                setSaved();
                if (m_onClose != null) {
                    m_onClose.onClose(
                        m_hasChangedSettings || hasChangedSettings.booleanValue(),
                        /*publishDialog=*/false);
                }
                clearEditor();
                // restore the scroll position
                RootPanel.getBodyElement().getOwnerDocument().setScrollTop(scrollTop);
            }
        });
    }

    /**
     * Sets the has changed flag and enables the save button.<p>
     */
    void setChanged() {

        m_hasChanges = true;
        enableSave();
        m_changedEntityIds.add(m_entityId);
        m_deletedEntities.remove(m_entityId);
        updateOverlayPosition();
        setEditorState(true);
    }

    /**
     * Sets the content definition.<p>
     *
     * @param definition the content definition
     */
    void setContentDefinition(CmsContentDefinition definition) {

        if (m_availableLocales.isEmpty()) {
            // only set the locales when initially setting the content definition
            m_availableLocales.putAll(definition.getAvailableLocales());
            m_contentLocales.addAll(definition.getContentLocales());
        } else {
            m_contentLocales.add(definition.getLocale());
        }
        m_title = definition.getTitle();
        m_sitePath = definition.getSitePath();
        m_resourceTypeName = definition.getResourceType();
        m_registeredEntities.add(definition.getEntityId());
        m_tabInfos = definition.getTabInfos();
        m_iconClasses = definition.getIconClasses();
        addContentDefinition(definition);
        CmsDefaultWidgetService service = (CmsDefaultWidgetService)getWidgetService();
        service.addConfigurations(definition.getConfigurations());
        service.setSyncValues(definition.getSyncValues());
        service.setSkipPaths(definition.getSkipPaths());
        addEntityChangeHandler(definition.getEntityId(), new ValueChangeHandler<CmsEntity>() {

            public void onValueChange(ValueChangeEvent<CmsEntity> event) {

                setChanged();
            }
        });
    }

    /**
     * Removes the delete on cancel flag for new resources.<p>
     */
    void setSaved() {

        setEditorState(false);
        m_deleteOnCancel = false;
    }

    /**
     * Call after save.<p>
     */
    void setUnchanged() {

        m_changedEntityIds.clear();
        m_deletedEntities.clear();
        m_hasChanges = false;
        disableSave(Messages.get().key(Messages.GUI_TOOLBAR_NOTHING_CHANGED_0));
    }

    /**
     * Enables and disabler the undo redo buttons according to the state.<p>
     *
     * @param state the undo redo state
     */
    void setUndoRedoState(UndoRedoState state) {

        if (state.hasUndo()) {
            m_undoButton.enable();
        } else {
            m_undoButton.disable(Messages.get().key(Messages.GUI_TOOLBAR_UNDO_DISABLED_0));
        }
        if (state.hasRedo()) {
            m_redoButton.enable();
        } else {
            m_redoButton.disable(Messages.get().key(Messages.GUI_TOOLBAR_REDO_DISABLED_0));
        }
    }

    /**
     * Returns true if the edited resource should be unlocked automatically after pressing Save/Exit.<p>
     *
     * @return true if the edited resource should be unlocked automatically
     */
    boolean shouldUnlockAutomatically() {

        if (m_isStandAlone) {
            if (m_isDirectEdit) {
                // Classic direct edit case - always unlock
                return true;
            } else {
                // Workplace case - determined by configuration
                return m_autoUnlock;
            }
        }
        // Container page case - always unlock
        return true;
    }

    /**
     * Shows the locked resource error message.<p>
     */
    void showLockedResourceMessage() {

        CmsErrorDialog dialog = new CmsErrorDialog(
            Messages.get().key(Messages.ERR_RESOURCE_ALREADY_LOCKED_BY_OTHER_USER_0),
            null);
        dialog.addCloseHandler(new CloseHandler<PopupPanel>() {

            public void onClose(CloseEvent<PopupPanel> event) {

                cancelEdit();
            }
        });
        dialog.center();
    }

    /**
     * Show the validation warning dialog on save.
     * @param issueInformation the validation issues
     * @param callback the callback to trigger to save
     */
    void showSaveValidationWarningDialog(
        Map<String, List<CmsPair<List<CmsPair<String, Integer>>, String>>> issueInformation,
        I_CmsSimpleCallback<?> callback) {

        Map<String, List<String>> issues = createIssueMap(issueInformation);

        CmsConfirmSaveDialog dialog = new CmsConfirmSaveDialog(issues, true, m_contentLocales.size() == 1, callback);

        dialog.center();

    }

    /**
     * Shows the validation error dialog.<p>
     *
     * @param issueInformation the validation issues
     */
    void showValidationErrorDialog(
        Map<String, List<CmsPair<List<CmsPair<String, Integer>>, String>>> issueInformation) {

        Map<String, List<String>> issues = createIssueMap(issueInformation);

        CmsConfirmSaveDialog dialog = new CmsConfirmSaveDialog(issues, false, m_contentLocales.size() == 1, null);

        dialog.center();

    }

    /**
     * Switches to the selected locale. Will save changes first.<p>
     *
     * @param locale the locale to switch to
     */
    void switchLocale(final String locale) {

        if (locale.equals(m_locale)) {
            return;
        }
        final Integer oldTabIndex = getTabIndex();
        internalSetLocale(locale);

        m_basePanel.clear();
        destroyForm(false);
        final CmsEntity entity = m_entityBackend.getEntity(m_entityId);
        m_entityId = getIdForLocale(locale);
        // if the content does not contain the requested locale yet, a new node will be created
        final boolean addedNewLocale = !m_contentLocales.contains(locale);
        if (m_registeredEntities.contains(m_entityId)) {
            unregistereEntity(m_entityId);
        }
        if (addedNewLocale) {
            loadNewDefinition(m_entityId, entity, new I_CmsSimpleCallback<CmsContentDefinition>() {

                public void execute(final CmsContentDefinition contentDefinition) {

                    setContentDefinition(contentDefinition);
                    renderFormContent();
                    if (oldTabIndex != null) {
                        if (oldTabIndex.intValue() < getFormTabs().getTabCount()) {
                            getFormTabs().selectTab(oldTabIndex.intValue());
                        }
                    }
                    setChanged();

                }
            });
        } else {
            loadDefinition(m_entityId, entity, new I_CmsSimpleCallback<CmsContentDefinition>() {

                public void execute(CmsContentDefinition contentDefinition) {

                    setContentDefinition(contentDefinition);
                    renderFormContent();
                    if (oldTabIndex != null) {
                        if (oldTabIndex.intValue() < getFormTabs().getTabCount()) {
                            getFormTabs().selectTab(oldTabIndex.intValue());
                        }
                    }
                }

            });
        }
    }

    /**
     * Synchronizes the locale independent fields to the other locales.<p>
     */
    void synchronizeCurrentLocale() {

        m_basePanel.clear();
        destroyForm(false);
        CmsEntity entity = m_entityBackend.getEntity(m_entityId);
        m_entityId = getIdForLocale(m_locale);
        ((CmsDefaultWidgetService)getWidgetService()).setSkipPaths(Collections.<String> emptyList());
        loadDefinition(m_entityId, entity, new I_CmsSimpleCallback<CmsContentDefinition>() {

            public void execute(CmsContentDefinition contentDefinition) {

                setContentDefinition(contentDefinition);
                renderFormContent();
                setChanged();
            }
        });
    }

    /**
     * Unlocks the edited resource.<p>
     */
    void unlockResource() {

        if (!shouldUnlockAutomatically()) {
            return;
        }
        if (m_entityId != null) {
            final CmsUUID structureId = CmsContentDefinition.entityIdToUuid(m_entityId);
            if (m_deleteOnCancel) {
                CmsRpcAction<Void> action = new CmsRpcAction<Void>() {

                    @Override
                    public void execute() {

                        CmsCoreProvider.getVfsService().syncDeleteResource(structureId, this);
                    }

                    @Override
                    protected void onResponse(Void result) {

                        // nothing to do
                    }
                };
                action.executeSync();
            } else {
                CmsCoreProvider.get().unlock(structureId);
            }
        }
    }

    /**
     * Updates the editor values.<p>
     *
     * @param previous the previous entity state
     * @param updated the updated entity state
     */
    void updateEditorValues(CmsEntity previous, CmsEntity updated) {

        if (!m_isDirectEdit && updated.getId().equals(m_entityId)) {
            // only apply the changes to the same locale entity
            updateEditorValues(previous, updated, getEntity(), Collections.<String> emptyList());
        }
    }

    /**
     * Updates the info header.<p>
     *
     * @param isSettingsTabSelected <code>true</code> if the element settings tab is selected
     */
    void updateInfoHeader(boolean isSettingsTabSelected) {

        m_basePanel.remove(0);
        m_basePanel.insert(isSettingsTabSelected ? m_pageInfoHeader : m_contentInfoHeader, 0);
    }

    /**
     * Update the validation context completely.
     */
    void updateValidation() {

        final CmsEntity entity = m_entityBackend.getEntity(m_entityId);
        final CmsValidationHandler validationHandler = getValidationHandler();
        getService().validateEntities(
            entity,
            m_clientId,
            new ArrayList<>(m_deletedEntities),
            getSkipPaths(),
            m_locale,
            new AsyncCallback<CmsValidationResult>() {

                @Override
                public void onFailure(Throwable caught) {

                    // TODO Auto-generated method stub

                }

                @Override
                public void onSuccess(CmsValidationResult result) {

                    CmsDebugLog.consoleLog("Update validation success: " + result);
                    validationHandler.updateValidationContext(result);
                    updateSaveButtons(result.hasErrors(), result.hasWarnings());

                }

            });
    }

    /**
     * Adds the change listener to the observer.<p>
     *
     * @param changeListener the change listener
     * @param changeScope the change scope
     */
    private void addChangeListener(JavaScriptObject changeListener, String changeScope) {

        try {
            System.out.println("Adding native listener for scope " + changeScope);
            m_entityObserver.addEntityChangeListener(new CmsEntityChangeListenerWrapper(changeListener), changeScope);
        } catch (Exception e) {

            CmsDebugLog.getInstance().printLine("Exception occured during listener registration" + e.getMessage());
        }
    }

    /**
     * Changes a simple type entity value.<p>
     *
     * @param attributeName the attribute name
     * @param index the value index
     * @param value the value
     * @param parentPathElements the parent path elements
     */
    private void changeSimpleValue(String attributeName, int index, String value, List<String> parentPathElements) {

        CmsAttributeHandler handler = getAttributeHandler(attributeName, parentPathElements);
        handler.changeValue(value, index);
    }

    /**
     * Closes the editor.<p>
     */
    private native void closeEditorWidow() /*-{
        if ($wnd.top.cms_ade_closeEditorDialog) {
            $wnd.top.cms_ade_closeEditorDialog();
        } else if ($wnd.parent.parent.cms_ade_closeEditorDialog) {
            $wnd.parent.parent.cms_ade_closeEditorDialog();
        } else {
            var backlink = $wnd[@org.opencms.ade.contenteditor.shared.rpc.I_CmsContentService::PARAM_BACKLINK];
            if (backlink) {
                $wnd.top.location.href = backlink;
            }
        }
    }-*/;

    /**
     * Creates a push button for the edit tool-bar.<p>
     *
     * @param title the button title
     * @param imageClass the image class
     *
     * @return the button
     */
    private CmsPushButton createButton(String title, String imageClass) {

        CmsPushButton result = new CmsPushButton();
        result.setTitle(title);
        result.setImageClass(imageClass);
        result.setButtonStyle(ButtonStyle.FONT_ICON, null);
        result.setSize(Size.big);
        return result;
    }

    /**
     * Creates the map from languages to localized element path information for all errors/warnings.
     * @param issueInformation the information on the warnings/errors
     * @return the map from languages to localized element path information for all errors/warnings.
     */
    private Map<String, List<String>> createIssueMap(
        Map<String, List<CmsPair<List<CmsPair<String, Integer>>, String>>> issueInformation) {

        I_CmsWidgetService service = getWidgetService();
        Map<String, List<String>> resultMap = new TreeMap<>();
        for (Entry<String, List<CmsPair<List<CmsPair<String, Integer>>, String>>> e : issueInformation.entrySet()) {
            String localeName = e.getKey();
            List<CmsPair<List<CmsPair<String, Integer>>, String>> items = e.getValue();
            List<String> localeItems = new ArrayList<>(items.size());
            resultMap.put(localeName, localeItems);
            for (CmsPair<List<CmsPair<String, Integer>>, String> it : items) {
                String path = "";
                for (CmsPair<String, Integer> partInfo : it.getFirst()) {
                    String attribute = partInfo.getFirst();
                    Integer idx = partInfo.getSecond();
                    path += service.getAttributeLabel(attribute);
                    if (idx.intValue() > 1) {
                        path += " [" + (idx) + "]";
                    }
                    path += " > ";
                }
                String issueDisplay = "<strong>"
                    + path.substring(0, path.length() - 3)
                    + "</strong> - "
                    + it.getSecond();
                localeItems.add(issueDisplay);
            }
        }
        return resultMap;
    }

    /**
     * Enables the save buttons.<p>
     */
    private void enableSave() {

        m_saveButton.enable();
        m_saveExitButton.enable();
        m_publishButton.enable();
    }

    /**
     * Exports the add entity change listener method.<p>
     */
    private native void exportObserver()/*-{
        var self = this;
        $wnd[@org.opencms.ade.contenteditor.client.CmsContentEditor::ADD_CHANGE_LISTENER_METHOD] = function(
                listener, scope) {
            var wrapper = {
                onChange : listener.onChange
            }
            self.@org.opencms.ade.contenteditor.client.CmsContentEditor::addChangeListener(Lcom/google/gwt/core/client/JavaScriptObject;Ljava/lang/String;)(wrapper, scope);
        }
        $wnd[@org.opencms.ade.contenteditor.client.CmsContentEditor::GET_CURRENT_ENTITY_METHOD] = function() {
            return new $wnd.acacia.CmsEntityWrapper(
                    self.@org.opencms.ade.contenteditor.client.CmsContentEditor::getCurrentEntity()());
        }
    }-*/;

    /**
     * Returns the attribute handler for the given attribute.<p>
     *
     * @param attributeName the attribute name
     * @param parentPathElements the parent path elements
     *
     * @return the attribute handler
     */
    private CmsAttributeHandler getAttributeHandler(String attributeName, List<String> parentPathElements) {

        List<String> childPathElements = new ArrayList<String>(parentPathElements);
        childPathElements.add(attributeName);
        CmsAttributeHandler handler = getRootAttributeHandler().getHandlerByPath(
            childPathElements.toArray(new String[childPathElements.size()]));
        return handler;
    }

    /**
     * Returns the entity id for the given locale.<p>
     *
     * @param locale the locale
     *
     * @return the entity id
     */
    private String getIdForLocale(String locale) {

        return CmsContentDefinition.uuidToEntityId(CmsContentDefinition.entityIdToUuid(m_entityId), locale);
    }

    /**
     * Returns the selected tab index, or null if there are no tabs.
     *
     * @return the selected tab index or null
     */
    private Integer getTabIndex() {

        if (getFormTabs() != null) {
            return Integer.valueOf(getFormTabs().getSelectedIndex());
        }
        return null;
    }

    /**
     * Initializes the window closing handler to ensure the resource will be unlocked when leaving the editor.<p>
     */
    private void initClosingHandler() {

        m_closingHandlerRegistration = Window.addWindowClosingHandler(new ClosingHandler() {

            /**
             * @see com.google.gwt.user.client.Window.ClosingHandler#onWindowClosing(com.google.gwt.user.client.Window.ClosingEvent)
             */
            public void onWindowClosing(ClosingEvent event) {

                unlockResource();
            }
        });
    }

    /**
     * Initializes the event preview handler.<p>
     */
    private void initEventPreviewHandler() {

        m_previewHandlerRegistration = Event.addNativePreviewHandler(new NativePreviewHandler() {

            public void onPreviewNativeEvent(NativePreviewEvent event) {

                previewNativeEvent(event);
            }
        });
    }

    /**
     * Initializes the locale selector.<p>
     */
    private void initLocaleSelect() {

        if (m_availableLocales.size() < 2) {
            return;
        }
        FlowPanel localeButtons = m_contentInfoHeader.getPathButtons();
        localeButtons.clear();
        Map<String, String> selectOptions = new HashMap<String, String>();
        int buttonLimit = CmsCoreProvider.get().getMaxLocaleButtons();
        for (Entry<String, String> localeEntry : m_availableLocales.entrySet()) {
            if (m_contentLocales.contains(localeEntry.getKey())) {
                final String locale = localeEntry.getKey();
                selectOptions.put(locale, localeEntry.getValue());
                if ((localeButtons.getWidgetCount() < buttonLimit) && !locale.equals(m_locale)) {
                    Label button = new Label(locale.toUpperCase());
                    localeButtons.add(button);
                    button.addClickHandler(event -> {
                        switchLocale(locale);
                    });
                }
            } else {
                selectOptions.put(localeEntry.getKey(), localeEntry.getValue() + " [-]");
            }
        }
        if (localeButtons.getWidgetCount() > 0) {
            Label label = new Label(m_locale.toUpperCase());
            label.addStyleName(I_CmsLayoutBundle.INSTANCE.editorCss().currentLocaleLabel());
            localeButtons.add(label);
        }
        if (m_localeSelect == null) {
            m_localeSelect = new CmsSelectBox(selectOptions);
            m_toolbar.insertRight(m_localeSelect, 1);
            m_localeSelect.addStyleName(I_CmsLayoutBundle.INSTANCE.generalCss().inlineBlock());
            m_localeSelect.getElement().getStyle().setWidth(100, Unit.PX);
            m_localeSelect.getElement().getStyle().setVerticalAlign(VerticalAlign.MIDDLE);
            m_localeSelect.addValueChangeHandler(new ValueChangeHandler<String>() {

                public void onValueChange(ValueChangeEvent<String> event) {

                    switchLocale(event.getValue());
                }
            });
        } else {
            m_localeSelect.setItems(selectOptions);
        }
        m_localeSelect.setFormValueAsString(m_locale);
        if (m_deleteLocaleButton == null) {
            m_deleteLocaleButton = createButton(
                Messages.get().key(Messages.GUI_TOOLBAR_DELETE_LOCALE_0),
                "opencms-icon-remove-locale");
            m_deleteLocaleButton.addClickHandler(new ClickHandler() {

                public void onClick(ClickEvent event) {

                    confirmDeleteLocale();
                }
            });
            m_toolbar.insertRight(m_deleteLocaleButton, 2);
        }
        if (m_contentLocales.size() > 1) {
            m_deleteLocaleButton.enable();
        } else {
            m_deleteLocaleButton.disable(Messages.get().key(Messages.GUI_TOOLBAR_CANT_DELETE_LAST_LOCALE_0));
        }
        if (m_copyLocaleButton == null) {
            m_copyLocaleButton = createButton(
                I_CmsButton.ButtonData.COPY_LOCALE_BUTTON.getTitle(),
                I_CmsButton.ButtonData.COPY_LOCALE_BUTTON.getIconClass());
            m_copyLocaleButton.addClickHandler(new ClickHandler() {

                public void onClick(ClickEvent event) {

                    openCopyLocaleDialog();
                }
            });
            m_toolbar.insertRight(m_copyLocaleButton, 3);
        }

    }

    /**
     * Generates the button bar displayed beneath the editable fields.<p>
     *
     * @param inline true if we are in inline editing mode
     */
    private void initToolbar(boolean inline) {

        m_hasErrors = false;
        m_hasWarnings = false;
        m_toolbar = new CmsToolbar();
        if (!inline) {
            m_toolbar.setComplexTitle(
                Messages.get().key(Messages.GUI_CONTENT_EDITOR_TITLE_0),
                Messages.get().key(Messages.GUI_CONTENT_EDITOR_TITLE_BOTTOM_0));
        } else {
            m_toolbar.setComplexTitle(
                Messages.get().key(Messages.GUI_CONTENT_EDITOR_TITLE_0),
                Messages.get().key(Messages.GUI_CONTENT_EDITOR_TITLE_BOTTOM_PAGE_EDITOR_0));
        }
        m_publishButton = createButton(
            I_CmsButton.ButtonData.PUBLISH_BUTTON.getTitle(),
            I_CmsButton.ButtonData.PUBLISH_BUTTON.getIconClass());
        m_toolbar.addLeft(m_publishButton);
        m_publishButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                boolean unlock = shouldUnlockAutomatically();

                saveAndDeleteEntities(unlock, new I_CmsSimpleCallback<Boolean>() {

                    public void execute(final Boolean hasChangedSeetings) {

                        setSaved();
                        HashMap<String, String> params = new HashMap<String, String>(
                            getContext().getPublishParameters());
                        CmsUUID structureId = CmsContentDefinition.entityIdToUuid(getEntityId());
                        params.put(CmsPublishOptions.PARAM_CONTENT, "" + structureId);
                        params.put(CmsPublishOptions.PARAM_START_WITH_CURRENT_PAGE, "");
                        CmsPublishDialog.showPublishDialog(params, new CloseHandler<PopupPanel>() {

                            public void onClose(CloseEvent<PopupPanel> closeEvent) {

                                if (m_onClose != null) {
                                    m_onClose.onClose(
                                        m_hasChangedSettings || hasChangedSeetings.booleanValue(),
                                        /*publishDialog=*/true);
                                }
                                clearEditor();
                            }
                        }, new Runnable() {

                            public void run() {

                                // ignore
                            }

                        }, null);

                    }
                });

            }
        });
        m_saveExitButton = createButton(
            Messages.get().key(Messages.GUI_TOOLBAR_SAVE_AND_EXIT_0),
            "opencms-icon-save-exit");
        m_saveExitButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                deferSaveAndExit();
            }
        });
        m_toolbar.addLeft(m_saveExitButton);
        m_saveButton = createButton(
            Messages.get().key(Messages.GUI_TOOLBAR_SAVE_0),
            I_CmsButton.ButtonData.SAVE_BUTTON.getIconClass());
        m_saveButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                deferSave();
            }
        });
        m_saveButton.setVisible(false);
        m_toolbar.addLeft(m_saveButton);
        disableSave(Messages.get().key(Messages.GUI_TOOLBAR_NOTHING_CHANGED_0));
        m_hasChanges = false;
        m_undoButton = createButton(Messages.get().key(Messages.GUI_TOOLBAR_UNDO_0), "opencms-icon-undo");
        m_undoButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                if (CmsUndoRedoHandler.getInstance().isIntitalized()) {
                    CmsUndoRedoHandler.getInstance().undo();
                }
            }
        });
        m_undoButton.disable(Messages.get().key(Messages.GUI_TOOLBAR_UNDO_DISABLED_0));
        m_undoButton.setVisible(false);
        m_toolbar.addLeft(m_undoButton);
        m_redoButton = createButton(Messages.get().key(Messages.GUI_TOOLBAR_REDO_0), "opencms-icon-redo");
        m_redoButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                if (CmsUndoRedoHandler.getInstance().isIntitalized()) {
                    CmsUndoRedoHandler.getInstance().redo();
                }
            }
        });
        m_redoButton.disable(Messages.get().key(Messages.GUI_TOOLBAR_REDO_DISABLED_0));
        m_redoButton.setVisible(false);
        m_toolbar.addLeft(m_redoButton);

        m_undoRedoHandlerRegistration = CmsUndoRedoHandler.getInstance().addValueChangeHandler(
            new ValueChangeHandler<CmsUndoRedoHandler.UndoRedoState>() {

                public void onValueChange(ValueChangeEvent<UndoRedoState> event) {

                    setUndoRedoState(event.getValue());
                }
            });
        m_openFormButton = createButton(
            Messages.get().key(Messages.GUI_TOOLBAR_OPEN_FORM_0),
            I_CmsButton.ButtonData.EDIT.getIconClass());
        m_openFormButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                initFormPanel();
                renderFormContent();
            }
        });
        m_toolbar.addLeft(m_openFormButton);

        m_hideHelpBubblesButton = new CmsToggleButton();

        m_hideHelpBubblesButton.setImageClass(I_CmsButton.ButtonData.TOGGLE_HELP.getIconClass());
        m_hideHelpBubblesButton.setButtonStyle(ButtonStyle.FONT_ICON, null);
        m_hideHelpBubblesButton.setSize(Size.big);
        m_hideHelpBubblesButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                CmsToggleButton button = (CmsToggleButton)event.getSource();
                hideHelpBubbles(!button.isDown());
            }
        });
        m_hideHelpBubblesButton.setDown(CmsCoreProvider.get().isShowEditorHelp());
        CmsValueFocusHandler.getInstance().hideHelpBubbles(RootPanel.get(), !CmsCoreProvider.get().isShowEditorHelp());
        if (!CmsCoreProvider.get().isShowEditorHelp()) {
            m_hideHelpBubblesButton.setTitle(Messages.get().key(Messages.GUI_TOOLBAR_HELP_BUBBLES_HIDDEN_0));
        } else {
            m_hideHelpBubblesButton.setTitle(Messages.get().key(Messages.GUI_TOOLBAR_HELP_BUBBLES_SHOWN_0));
        }
        m_toolbar.addRight(m_hideHelpBubblesButton);

        m_cancelButton = createButton(
            Messages.get().key(Messages.GUI_TOOLBAR_RESET_0),
            I_CmsButton.ButtonData.RESET_BUTTON.getIconClass());
        m_cancelButton.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {

                confirmCancel();
            }
        });
        m_toolbar.addRight(m_cancelButton);
        RootPanel.get().add(m_toolbar);
    }

    /**
     * Sets both this object's locale field and a Javascript variable that can be used to access the locale from nested iframes.
     *
     * @param locale the locale to set
     */
    private void internalSetLocale(String locale) {

        m_locale = locale;
        JsPropertyMap<Object> window = Js.cast(DomGlobal.window);
        if (locale != null) {
            window.set(CmsGwtConstants.ATTR_CONTENT_EDITOR_LOCALE, locale);
        } else {
            window.delete(CmsGwtConstants.ATTR_CONTENT_EDITOR_LOCALE);
        }
    }

    /**
     * Sets the editor state.<p>
     *
     * @param changed if the content has been changed
     */
    private native void setEditorState(boolean changed)/*-{
        if (typeof $wnd.cmsSetEditorChangedState === 'function') {
            $wnd.cmsSetEditorChangedState(changed);
        }
    }-*/;

    /**
     * Sets the resource info to native window context variables.<p>
     *
     * @param sitePath the site path
     * @param locale the content locale
     */
    private native void setNativeResourceInfo(String sitePath, String locale)/*-{
        $wnd._editResource = sitePath;
        $wnd._editLanguage = locale;
    }-*/;

    /**
     * Updates the editor values according to the given entity.<p>
     *
     * @param previous the previous entity state
     * @param updated the updated entity state
     * @param target the target entity
     * @param parentPathElements the parent path elements
     */
    private void updateEditorValues(
        CmsEntity previous,
        CmsEntity updated,
        CmsEntity target,
        List<String> parentPathElements) {

        for (String attributeName : m_entityBackend.getType(target.getTypeName()).getAttributeNames()) {
            CmsAttributeHandler handler = getAttributeHandler(attributeName, parentPathElements);
            if (handler == null) {
                // non visible attribute, skip it
                continue;
            }
            if (previous.hasAttribute(attributeName)
                && updated.hasAttribute(attributeName)
                && target.hasAttribute(attributeName)) {
                CmsEntityAttribute updatedAttribute = updated.getAttribute(attributeName);
                CmsEntityAttribute previousAttribute = previous.getAttribute(attributeName);
                CmsEntityAttribute targetAttribute = target.getAttribute(attributeName);
                if (updatedAttribute.isSimpleValue()) {
                    if ((updatedAttribute.getValueCount() == previousAttribute.getValueCount())
                        && (updatedAttribute.getValueCount() == targetAttribute.getValueCount())) {
                        for (int i = 0; i < updatedAttribute.getValueCount(); i++) {
                            if (!updatedAttribute.getSimpleValues().get(i).equals(
                                previousAttribute.getSimpleValues().get(i))
                                && previousAttribute.getSimpleValues().get(i).equals(
                                    targetAttribute.getSimpleValues().get(i))) {

                                changeSimpleValue(
                                    attributeName,
                                    i,
                                    updatedAttribute.getSimpleValues().get(i),
                                    parentPathElements);
                            }
                        }
                    } else {
                        if (targetAttribute.getValueCount() == previousAttribute.getValueCount()) {
                            // only act, if the value count has not been altered while executing the server request
                            if (updatedAttribute.getValueCount() > previousAttribute.getValueCount()) {
                                // new values have been added
                                for (int i = 0; i < updatedAttribute.getValueCount(); i++) {
                                    if (i >= previousAttribute.getSimpleValues().size()) {
                                        handler.addNewAttributeValue(updatedAttribute.getSimpleValues().get(i));
                                    } else if (!updatedAttribute.getSimpleValues().get(i).equals(
                                        previousAttribute.getSimpleValues().get(i))
                                        && previousAttribute.getSimpleValues().get(i).equals(
                                            targetAttribute.getSimpleValues().get(i))) {
                                        changeSimpleValue(
                                            attributeName,
                                            i,
                                            updatedAttribute.getSimpleValues().get(i),
                                            parentPathElements);
                                    }
                                }
                            } else {
                                // values have been removed
                                for (int i = previousAttribute.getValueCount() - 1; i >= 0; i--) {
                                    if (i >= updatedAttribute.getSimpleValues().size()) {
                                        handler.removeAttributeValue(i);
                                    } else if (!updatedAttribute.getSimpleValues().get(i).equals(
                                        previousAttribute.getSimpleValues().get(i))
                                        && previousAttribute.getSimpleValues().get(i).equals(
                                            targetAttribute.getSimpleValues().get(i))) {
                                        changeSimpleValue(
                                            attributeName,
                                            i,
                                            updatedAttribute.getSimpleValues().get(i),
                                            parentPathElements);
                                    }
                                }
                            }
                        }
                    }
                } else {
                    if (targetAttribute.getValueCount() == previousAttribute.getValueCount()) {
                        // only act, if the value count has not been altered while executing the server request
                        if (updatedAttribute.getValueCount() > previousAttribute.getValueCount()) {
                            // new values have been added
                            for (int i = 0; i < updatedAttribute.getValueCount(); i++) {
                                if (i >= previousAttribute.getSimpleValues().size()) {
                                    handler.addNewAttributeValue(
                                        m_entityBackend.registerEntity(
                                            updatedAttribute.getComplexValues().get(i),
                                            true));
                                } else {
                                    List<String> childPathElements = new ArrayList<String>(parentPathElements);
                                    childPathElements.add(attributeName + "[" + i + "]");
                                    updateEditorValues(
                                        previousAttribute.getComplexValues().get(i),
                                        updatedAttribute.getComplexValues().get(i),
                                        targetAttribute.getComplexValues().get(i),
                                        childPathElements);
                                }
                            }
                        } else {
                            // values have been removed
                            for (int i = previousAttribute.getValueCount() - 1; i >= 0; i--) {
                                if (i >= updatedAttribute.getValueCount()) {

                                    handler.removeAttributeValue(i);
                                } else {
                                    List<String> childPathElements = new ArrayList<String>(parentPathElements);
                                    childPathElements.add(attributeName + "[" + i + "]");
                                    updateEditorValues(
                                        previousAttribute.getComplexValues().get(i),
                                        updatedAttribute.getComplexValues().get(i),
                                        targetAttribute.getComplexValues().get(i),
                                        childPathElements);
                                }
                            }
                        }
                    }
                }
            } else if (previous.hasAttribute(attributeName) && target.hasAttribute(attributeName)) {
                for (int i = target.getAttribute(attributeName).getValueCount() - 1; i >= 0; i--) {
                    handler.removeAttributeValue(i);
                }

            } else if (!previous.hasAttribute(attributeName)
                && !target.hasAttribute(attributeName)
                && updated.hasAttribute(attributeName)) //
            {
                CmsEntityAttribute updatedAttribute = updated.getAttribute(attributeName);
                for (int i = 0; i < updatedAttribute.getValueCount(); i++) {
                    if (updatedAttribute.isSimpleValue()) {
                        handler.addNewAttributeValue(updatedAttribute.getSimpleValues().get(i));
                    } else {
                        handler.addNewAttributeValue(
                            m_entityBackend.registerEntity(updatedAttribute.getComplexValues().get(i), true));
                    }
                }
            }
        }
    }

    /**
     * Updates the styles at the save buttons.
     * @param hasErrors flag, indicating if we have errors
     * @param hasWarnings flag, indicating if we have warnings
     */
    private void updateSaveButtons(boolean hasErrors, boolean hasWarnings) {

        if (m_hasErrors && !hasErrors) {
            m_saveButton.removeStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsError());
            m_saveExitButton.removeStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsError());
            m_publishButton.removeStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsError());
            m_hasErrors = false;
        }
        if (m_hasWarnings && (hasErrors || !hasWarnings)) {
            m_saveButton.removeStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsWarning());
            m_saveExitButton.removeStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsWarning());
            m_publishButton.removeStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsWarning());
            m_hasWarnings = false;
        }
        if (!m_hasErrors && hasErrors) {
            m_saveButton.addStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsError());
            m_saveExitButton.addStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsError());
            m_publishButton.addStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsError());
            m_hasErrors = true;
        } else if (!m_hasWarnings && !m_hasErrors && hasWarnings) {
            m_saveButton.addStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsWarning());
            m_saveExitButton.addStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsWarning());
            m_publishButton.addStyleName(I_CmsLayoutBundle.INSTANCE.buttonCss().cmsWarning());
            m_hasWarnings = true;
        }
        if (m_isSaveDisabled && (m_hasErrors || m_hasWarnings)) {
            enableSave();
        }
    }
}