/*
    * Themis: Java Project Framework
    * 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.themis.lethe.analysis;
  
  import io.github.tonywasher.joceanus.oceanus.base.OceanusException;
  import io.github.tonywasher.joceanus.themis.lethe.analysis.ThemisAnalysisContainer.ThemisAnalysisAdoptable;
  import io.github.tonywasher.joceanus.themis.lethe.analysis.ThemisAnalysisStatement.ThemisAnalysisStatementHolder;
  
  import java.util.ArrayDeque;
  import java.util.Collections;
  import java.util.Deque;
  import java.util.Iterator;
  
  /**
   * If construct.
   */
  public class ThemisAnalysisIf
          implements ThemisAnalysisContainer, ThemisAnalysisAdoptable, ThemisAnalysisStatementHolder {
      /**
       * The condition.
       */
      private final ThemisAnalysisStatement theCondition;
  
      /**
       * The contents.
       */
      private final Deque<ThemisAnalysisElement> theContents;
  
      /**
       * The else clause.
       */
      private final ThemisAnalysisElse theElse;
  
      /**
       * The number of lines.
       */
      private final int theNumLines;
  
      /**
       * The dataMap.
       */
      private final ThemisAnalysisDataMap theDataMap;
  
      /**
       * The parent.
       */
      private ThemisAnalysisContainer theParent;
  
      /**
       * Constructor.
       *
       * @param pParser the parser
       * @param pLine   the initial if line
       * @throws OceanusException on error
       */
      ThemisAnalysisIf(final ThemisAnalysisParser pParser,
                       final ThemisAnalysisLine pLine) throws OceanusException {
          /* Access details from parser */
          theParent = pParser.getParent();
          theDataMap = new ThemisAnalysisDataMap(theParent.getDataMap());
  
          /* Parse the condition */
          final Deque<ThemisAnalysisElement> myHeaders = ThemisAnalysisBuilder.parseHeaders(pParser, pLine);
          theNumLines = myHeaders.size() + 1;
          theCondition = new ThemisAnalysisStatement(myHeaders);
  
          /* Parse the body */
          final Deque<ThemisAnalysisElement> myLines = ThemisAnalysisBuilder.processBody(pParser);
  
          /* Look for else clauses */
          theElse = (ThemisAnalysisElse) pParser.processExtra(this, ThemisAnalysisKeyWord.ELSE);
  
          /* Create a parser */
          theContents = new ArrayDeque<>();
          final ThemisAnalysisParser myParser = new ThemisAnalysisParser(myLines, theContents, this);
          myParser.processLines();
      }
  
      @Override
      public Deque<ThemisAnalysisElement> getContents() {
          return theContents;
      }
  
      @Override
      public Iterator<ThemisAnalysisStatement> statementIterator() {
         final Iterator<ThemisAnalysisStatement> myLocal = Collections.singleton(theCondition).iterator();
         return theElse == null ? myLocal : new ThemisIteratorChain<>(myLocal, theElse.statementIterator());
     }
 
     @Override
     public ThemisAnalysisContainer getParent() {
         return theParent;
     }
 
     @Override
     public void setParent(final ThemisAnalysisContainer pParent) {
         theParent = pParent;
         theDataMap.setParent(pParent.getDataMap());
         if (theElse != null) {
             theElse.setParent(pParent);
         }
     }
 
     @Override
     public ThemisAnalysisDataMap getDataMap() {
         return theDataMap;
     }
 
     @Override
     public void postProcessExtras() throws OceanusException {
         /* Process the else clause if required */
         if (theElse != null) {
             theElse.postProcessLines();
         }
     }
 
     /**
      * Obtain the additional else clause (if any).
      *
      * @return the else clause
      */
     public ThemisAnalysisElse getElse() {
         return theElse;
     }
 
     @Override
     public Iterator<ThemisAnalysisContainer> containerIterator() {
         return theElse == null
                 ? Collections.emptyIterator()
                 : theElse.containerIterator();
     }
 
     @Override
     public int getNumLines() {
         return theNumLines;
     }
 
     @Override
     public String toString() {
         return theCondition.toString();
     }
 
     /**
      * Chained Iterator.
      *
      * @param <T> the item class
      */
     public static class ThemisIteratorChain<T> implements Iterator<T> {
         /**
          * Local Iterator.
          */
         private final Iterator<T> theLocal;
 
         /**
          * Chained Iterator.
          */
         private final Iterator<T> theChained;
 
         /**
          * Constructor.
          *
          * @param pLocal   the local iterator
          * @param pChained the chained iterator
          */
         public ThemisIteratorChain(final Iterator<T> pLocal,
                                    final Iterator<T> pChained) {
             theLocal = pLocal;
             theChained = pChained;
         }
 
         @Override
         public boolean hasNext() {
             return theLocal.hasNext() || theChained.hasNext();
         }
 
         @Override
         public T next() {
             return theLocal.hasNext() ? theLocal.next() : theChained.next();
         }
     }
 
     /**
      * Reduced Iterator.
      *
      * @param <T> the item class
      */
     public static class ThemisReducedIterator<T> implements Iterator<T> {
         /**
          * Local Iterator.
          */
         private final Iterator<? extends T> theBase;
 
         /**
          * Constructor.
          *
          * @param pBase the base iterator
          */
         public ThemisReducedIterator(final Iterator<? extends T> pBase) {
             theBase = pBase;
         }
 
         @Override
         public boolean hasNext() {
             return theBase.hasNext();
         }
 
         @Override
         public T next() {
             return theBase.next();
         }
     }
 }