/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.devacfr.maven.skins.reflow.model;
  
  import javax.annotation.Nonnull;
  import javax.annotation.Nullable;
  
  import java.util.List;
  import java.util.Set;
  
  import com.google.common.collect.Sets;
  import org.apache.commons.lang3.builder.ToStringBuilder;
  import org.devacfr.maven.skins.reflow.HtmlTool;
  import org.devacfr.maven.skins.reflow.HtmlTool.IdElement;
  import org.devacfr.maven.skins.reflow.ISkinConfig;
  import org.devacfr.maven.skins.reflow.Xpp3Utils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Represents the base of Table of content component.
   *
   * @author devacfr
   * @since 2.0
   * @param <T>
   *            the type of inherit of {@link Toc}.
   */
  public abstract class Toc<T extends Toc<?>> extends BsComponent {
  
      private static final Set<String> TOC_TYPES = Sets.newHashSet("sidebar", "top", "false");
  
      /** */
      public static final String COMPONENT = "toc";
  
      /** */
      private static final Logger LOGGER = LoggerFactory.getLogger(Toc.class);
  
      /** enable by default */
      private boolean enabled = true;
  
      /** */
      private final String type;
  
      /**
       * @param config
       *            a config (can <b>not</b> be {@code null}).
       * @param preferredType
       *            the default type of Toc to use.
       * @return Returns new instance corresponding {@link Toc} to configuration.
       */
      public static Toc<?> createToc(@Nonnull final ISkinConfig config, @Nullable final String preferredType) {
          Toc<?> toc = null;
          String type = config.getPropertyValue(COMPONENT, String.class, preferredType);
          if (LOGGER.isTraceEnabled()) {
              LOGGER.trace("Page '{}' Find Toc: {}", config.getFileId(), type);
          }
          if (!TOC_TYPES.contains(type)) {
              type = preferredType;
          }
          if (type == null) {
              type = "";
          }
          switch (type) {
              case "sidebar":
                  toc = createSidebar(config);
                  break;
              case "top":
                  toc = createTopBar(config);
                  break;
              default:
                  // create a disabled empty toc
                  toc = new Toc<Toc<?>>("", "") {};
  
                  toc.withEnabled(false);
                  break;
          }
  
          return toc;
      }
  
      /**
       * @param config
       *            a config (can <b>not</b> be {@code null}).
      * @return Returns new instance of Toc sidebar.
      */
     public static Toc<?> createSidebar(@Nonnull final ISkinConfig config) {
         return new TocSidebar(config);
     }
 
     /**
      * @param config
      *            a config (can <b>not</b> be {@code null}).
      * @return Returns new instance Toc top bar.
      */
     public static Toc<?> createTopBar(@Nonnull final ISkinConfig config) {
         return new TocTopBar(config);
     }
 
     /**
      * @param type
      *            the {@link String} representation of Toc.
      * @param component
      *            the bootstrap component name.
      */
     protected Toc(final String type, final String component) {
         super(component);
         this.type = type;
     }
 
     /**
      * @return Returns the fluent instance.
      */
     @SuppressWarnings("unchecked")
     protected T self() {
         return (T) this;
     }
 
     /**
      * @return Returns the {@link String} reprensenting the type of {@link Toc}.
      */
     public String getType() {
         return type;
     }
 
     /**
      * Gets the indicating whether is enable.
      *
      * @return Returns {@code true} if is enable, otherwise {@code false}.
      */
     public boolean isEnabled() {
         return enabled;
     }
 
     /**
      * @param skinConfig
      *            a config (can <b>not</b> be {@code null}).
      * @return Returns a list of {@link IdElement} representing the heading tree containing in current page.
      * @since 2.1
      */
     public List<? extends IdElement> getTocItems(final ISkinConfig skinConfig) {
         final HtmlTool htmlTool = getHtmlTool(skinConfig);
         final String bodyContent = getBodyContent(skinConfig);
 
         final List<? extends IdElement> tocItems = htmlTool.headingTree(bodyContent,
             Xpp3Utils.getChildren(skinConfig.get("sections")));
         return tocItems;
     }
 
     /**
      * Sets the indicating whether is enable.
      *
      * @param enabled
      *            status to use.
      * @return Returns the fluent instance.
      */
     protected T withEnabled(final boolean enabled) {
         this.enabled = enabled;
         return self();
     }
 
     @Override
     protected String onPreRender(final @Nonnull ISkinConfig skinConfig, final @Nonnull String bodyContent) {
         if (this.enabled) {
             final HtmlTool htmlTool = getHtmlTool(skinConfig);
             return htmlTool.ensureHeadingIds(skinConfig.getContext().getType(),
                 skinConfig.getFileId(),
                 bodyContent,
                 HtmlTool.DEFAULT_SLUG_SEPARATOR);
         }
         return bodyContent;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String toString() {
         return ToStringBuilder.reflectionToString(this);
     }
 }