JuniperFlattener.java

package org.batfish.grammar.juniper;

import java.util.ArrayList;
import java.util.List;

import org.batfish.grammar.juniper.JuniperParser.*;

public class JuniperFlattener extends JuniperParserBaseListener {

   private List<String> _currentBracketedWords;

   private List<String> _currentStatement;

   private String _flattenedConfigurationText;

   private final String _header;

   private StatementContext _inactiveStatement;

   private boolean _inBrackets;

   private List<String> _setStatements;

   private List<List<String>> _stack;

   public JuniperFlattener(String header) {
      _header = header;
      _stack = new ArrayList<>();
      _setStatements = new ArrayList<>();
   }

   @Override
   public void enterBracketed_clause(Bracketed_clauseContext ctx) {
      if (_inactiveStatement == null) {
         _currentBracketedWords = new ArrayList<>();
         _inBrackets = true;
      }
   }

   @Override
   public void enterStatement(StatementContext ctx) {
      if (_inactiveStatement == null) {
         if (ctx.INACTIVE() != null) {
            _inactiveStatement = ctx;
         }
         else {
            _currentStatement = new ArrayList<>();
            _stack.add(_currentStatement);
         }
      }
   }

   @Override
   public void exitBracketed_clause(Bracketed_clauseContext ctx) {
      if (_inactiveStatement == null) {
         _inBrackets = false;
      }
   }

   @Override
   public void exitJuniper_configuration(Juniper_configurationContext ctx) {
      StringBuilder sb = new StringBuilder();
      sb.append(_header);
      for (String setStatement : _setStatements) {
         sb.append(setStatement + "\n");
      }
      _flattenedConfigurationText = sb.toString();
   }

   @Override
   public void exitStatement(StatementContext ctx) {
      if (_inactiveStatement == null) {
         _stack.remove(_stack.size() - 1);
      }
      else if (_inactiveStatement == ctx) {
         _inactiveStatement = null;
      }
   }

   @Override
   public void exitTerminator(TerminatorContext ctx) {
      if (_inactiveStatement == null) {
         StringBuilder sb = new StringBuilder();
         sb.append("set");
         for (List<String> prefix : _stack) {
            for (String word : prefix) {
               sb.append(" " + word);
            }
         }
         String setStatementBase = sb.toString();
         if (_currentBracketedWords != null) {
            for (String bracketedWord : _currentBracketedWords) {
               String setStatement = setStatementBase + " " + bracketedWord;
               _setStatements.add(setStatement);
            }
            _currentBracketedWords = null;
         }
         else {
            _setStatements.add(setStatementBase);
         }
      }
   }

   @Override
   public void exitWord(WordContext ctx) {
      if (_inactiveStatement == null) {
         String word = ctx.getText();
         if (_inBrackets) {
            _currentBracketedWords.add(word);
         }
         else {
            _currentStatement.add(word);
         }
      }
   }

   public String getFlattenedConfigurationText() {
      return _flattenedConfigurationText;
   }

}