/**
    * This file Copyright (c) 2018 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.ui.field.factory;
  
  import static com.google.common.base.Enums.getIfPresent;
  import static org.apache.commons.io.FilenameUtils.getExtension;
  import static org.apache.commons.lang3.StringUtils.isNotBlank;
  import static org.vaadin.aceeditor.AceMode.forFileEnding;
  
  import info.magnolia.context.MgnlContext;
  import info.magnolia.objectfactory.ComponentProvider;
  import info.magnolia.ui.api.location.LocationController;
  import info.magnolia.ui.field.CodeFieldDefinition;
  import info.magnolia.ui.vaadin.extension.ShortcutProtector;
  
  import java.util.Collections;
  import java.util.Optional;
  
  import javax.inject.Inject;
  
  import org.apache.commons.lang3.StringUtils;
  import org.vaadin.aceeditor.AceEditor;
  import org.vaadin.aceeditor.AceMode;
  
  import com.vaadin.event.ShortcutAction;
  import com.vaadin.server.Sizeable;
  
  /**
   * Creates and initializes a code field, based on the {@link AceEditor} add-on for Vaadin.
   */
  public class CodeFieldFactory extends AbstractFieldFactory<String, CodeFieldDefinition> {
  
      private static final String FREEMARKER_LANGUAGE = "freemarker";
      private static final String ACE_EDITOR_FTL_ID = "ftl";
      private static final String ACE_EDITOR_RESOURCES = "/.resources/ace/";
  
      private AceEditor field;
  
      private final CodeFieldDefinition definition;
      private final LocationController locationController;
  
      @Inject
      public CodeFieldFactory(CodeFieldDefinition definition, ComponentProvider componentProvider, LocationController locationController) {
          super(definition, componentProvider);
          this.definition = definition;
          this.locationController = locationController;
      }
  
      @Override
      protected AceEditor createFieldComponent() {
          field = newAceEditor();
  
          // Set style
          field.setStyleName("textcodefield");
          field.setUseWorker(false);
  
          ShortcutProtector.extend(field, Collections.singletonList(ShortcutAction.KeyCode.ENTER));
  
          return field;
      }
  
      /**
       * @return newly constructed {@link AceEditor}.
       */
      protected AceEditor newAceEditor() {
          AceEditor aceEditor = new AceEditor();
          if (MgnlContext.isWebContext()) {
              String aceEditorResourcePath = MgnlContext.getContextPath() + ACE_EDITOR_RESOURCES;
             aceEditor.setModePath(aceEditorResourcePath);
             aceEditor.setWorkerPath(aceEditorResourcePath);
             aceEditor.setThemePath(aceEditorResourcePath);
         }
 
         // If language is set, then we don't want to conflict with it.
         if (isNotBlank(definition.getLanguage())) {
             aceEditor.setMode(getModeType(definition.getLanguage()));
         } else {
             String fileName = resolvePath();
             if (fileName != null) {
                 String extension = getExtension(fileName);
                 AceMode mode = getAceModeByFileExtension(extension);
                 if (mode != null) {
                     aceEditor.setMode(mode);
                 }
             }
         }
 
         if (definition.getHeight() > 0) {
             aceEditor.setHeight(definition.getHeight(), Sizeable.Unit.PIXELS);
         }
 
         return aceEditor;
     }
 
     protected String resolvePath() {
         return StringUtils.substringBefore(locationController.getWhere().getParameter(), ":");
     }
 
     /**
      * Get Ace-editor compliant mode type name for a language.
      *
      * TODO: currently only 'freemarker' -> 'ftl' case is handled, otherwise the method returns the string from definition.
      * If needed we could craft our own mapping from human-readable language names into the Ace editor mode identifiers.
      */
     private String getModeType(String language) {
         return FREEMARKER_LANGUAGE.equals(language) ? ACE_EDITOR_FTL_ID : language;
     }
 
     /**
      * Get the {@link AceMode} by file extension.
      * <p>
      * First tries to match the given extension against an AceMode value, otherwise looks into AceMode's additional mappings (<code>endingModeMap</code>).
      */
     private AceMode getAceModeByFileExtension(String extension) {
         // Trying the get AceMode from the Enum
         Optional<AceMode> aceModeValue = getIfPresent(AceMode.class, extension).toJavaUtil();
         // Trying to get AceMode from the AceMode.endingModeMap
         return aceModeValue.orElseGet(() -> forFileEnding(extension));
     }
 
 }