/*
    * Tethys: GUI Utilities
    * Copyright 2012-2026. Tony Washer
    *
    * Licensed under the Apache License, Version 2.0 (the "License"); you may not
    * use this file except in compliance with the License.  You may obtain a copy
    * of the License at
    *
    *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
   * License for the specific language governing permissions and limitations under
   * the License.
   */
  package io.github.tonywasher.joceanus.tethys.core.control;
  
  import io.github.tonywasher.joceanus.oceanus.base.OceanusException;
  import io.github.tonywasher.joceanus.oceanus.event.OceanusEventManager;
  import io.github.tonywasher.joceanus.oceanus.event.OceanusEventRegistrar;
  import io.github.tonywasher.joceanus.oceanus.logger.OceanusLogManager;
  import io.github.tonywasher.joceanus.oceanus.logger.OceanusLogger;
  import io.github.tonywasher.joceanus.oceanus.resource.OceanusResourceLoader;
  import io.github.tonywasher.joceanus.tethys.api.base.TethysUIEvent;
  import io.github.tonywasher.joceanus.tethys.api.base.TethysUIValueSet;
  import io.github.tonywasher.joceanus.tethys.api.control.TethysUIHTMLManager;
  import io.github.tonywasher.joceanus.tethys.core.base.TethysUICoreComponent;
  import io.github.tonywasher.joceanus.tethys.core.factory.TethysUICoreFactory;
  
  /**
   * HTML Manager.
   */
  public abstract class TethysUICoreHTMLManager
          extends TethysUICoreComponent
          implements TethysUIHTMLManager {
      /**
       * The logger.
       */
      private static final OceanusLogger LOGGER = OceanusLogManager.getLogger(TethysUICoreHTMLManager.class);
  
      /**
       * Reference Separator.
       */
      private static final String REF_SEPARATOR = "#";
  
      /**
       * The id.
       */
      private final Integer theId;
  
      /**
       * The Event Manager.
       */
      private final OceanusEventManager<TethysUIEvent> theEventManager;
  
      /**
       * The HTMLToFile Manager.
       */
      private final TethysUICoreHTMLToFile theHTMLToFile;
  
      /**
       * The ValueSet.
       */
      private final TethysUIValueSet theValueSet;
  
      /**
       * The Current reference.
       */
      private String theCurrentRef;
  
      /**
       * CSS Base.
       */
      private String theCSSBase;
  
      /**
       * CSS Processed.
       */
      private String theCSSProcessed;
  
      /**
       * HTML String.
       */
      private String theHTMLString;
  
      /**
       * Constructor.
       *
       * @param pFactory the GUI Factory
       */
      protected TethysUICoreHTMLManager(final TethysUICoreFactory<?> pFactory) {
          /* Build standard fields */
          theId = pFactory.getNextId();
          theEventManager = new OceanusEventManager<>();
  
          /* Create the HTMLtoFile Manager */
          theHTMLToFile = new TethysUICoreHTMLToFile(pFactory, this);
  
         /* Obtain the valueSet */
         theValueSet = pFactory.getValueSet();
 
         /* Listen to valueSet changes */
         theValueSet.getEventRegistrar().addEventListener(e -> processCSS());
     }
 
     @Override
     public Integer getId() {
         return theId;
     }
 
     @Override
     public OceanusEventRegistrar<TethysUIEvent> getEventRegistrar() {
         return theEventManager.getEventRegistrar();
     }
 
     /**
      * Obtain the HTML String.
      *
      * @return the string
      */
     protected String getHTMLString() {
         return theHTMLString;
     }
 
     /**
      * Obtain the processed CSS.
      *
      * @return the CSS
      */
     protected String getProcessedCSS() {
         return theCSSProcessed;
     }
 
     @Override
     public void processReference(final String pReference) {
         /* Access local copy of reference */
         String myRef = pReference;
         String myInternal = null;
 
         /* If the name has a # in it */
         if (myRef.contains(REF_SEPARATOR)) {
             /* Split on the # */
             final String[] myTokens = myRef.split(REF_SEPARATOR);
 
             /* Allocate the values */
             myRef = myTokens[0];
             myInternal = myTokens[1];
 
             /* Handle an internal reference */
             if (myRef.isEmpty()) {
                 myRef = null;
             }
         }
 
         /* Check whether we need to switch pages */
         final boolean needSwitch = (myRef != null)
                 && !myRef.equals(theCurrentRef);
 
         /* If we failed to switch pages */
         if (needSwitch
                 && !loadNewPage(myRef)) {
             /* Don't attempt to scroll to internal reference */
             myInternal = null;
             LOGGER.error("Failed to load page <%s>", myRef);
         }
 
         /* If we have an internal reference */
         if (myInternal != null) {
             /* Scroll to the reference */
             scrollToReference(myInternal);
         }
     }
 
     @Override
     public void setHTMLContent(final String pHTMLString,
                                final String pReference) {
         /* Store the reference and string */
         theCurrentRef = pReference;
         theHTMLString = pHTMLString;
 
         /* load the content */
         loadHTMLContent(theHTMLString);
     }
 
     /**
      * Load HTML Contents.
      *
      * @param pHTMLString the HTML content.
      */
     protected abstract void loadHTMLContent(String pHTMLString);
 
     /**
      * Load CSS Contents.
      */
     protected abstract void loadCSSContents();
 
     @Override
     public void setCSSContent(final TethysUIStyleSheetId pStyleSheet) throws OceanusException {
         /* Store the base sheet */
         theCSSBase = OceanusResourceLoader.loadResourceToString(pStyleSheet);
         theCSSProcessed = null;
 
         /* Process the CSS */
         processCSS();
     }
 
     /**
      * Process the CSS.
      */
     protected void processCSS() {
         /* If we have a styleSheet */
         if (theCSSBase != null) {
             /* Process the CSS */
             theCSSProcessed = theValueSet.resolveValues(theCSSBase);
         }
 
         /* reLoad the CSS */
         loadCSSContents();
     }
 
     @Override
     public void saveToFile() {
         theHTMLToFile.writeToFile();
     }
 
     /**
      * Load new page.
      *
      * @param pPageRef the page reference
      * @return was new page loaded? true/false
      */
     private boolean loadNewPage(final String pPageRef) {
         return !theEventManager.fireEvent(TethysUIEvent.BUILDPAGE, pPageRef);
     }
 }