////////////////////////////////////////////////////////////////////////////////
   // checkstyle: Checks Java source code for adherence to a set of rules.
   // Copyright (C) 2001-2019 the original author or authors.
   //
   // This library is free software; you can redistribute it and/or
   // modify it under the terms of the GNU Lesser General Public
   // License as published by the Free Software Foundation; either
   // version 2.1 of the License, or (at your option) any later version.
   //
  // This library is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  // Lesser General Public License for more details.
  //
  // You should have received a copy of the GNU Lesser General Public
  // License along with this library; if not, write to the Free Software
  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  ////////////////////////////////////////////////////////////////////////////////
  
  package com.puppycrawl.tools.checkstyle.checks.coding;
  
  import java.util.Arrays;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Set;
  import java.util.stream.Collectors;
  
  import com.puppycrawl.tools.checkstyle.StatelessCheck;
  import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
  import com.puppycrawl.tools.checkstyle.api.DetailAST;
  import com.puppycrawl.tools.checkstyle.api.FullIdent;
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  import com.puppycrawl.tools.checkstyle.utils.CheckUtil;
  
  /**
   * Catching java.lang.Exception, java.lang.Error or java.lang.RuntimeException
   * is almost never acceptable.
   */
  @StatelessCheck
  public final class IllegalCatchCheck extends AbstractCheck {
  
      /**
       * A key is pointing to the warning message text in "messages.properties"
       * file.
       */
      public static final String MSG_KEY = "illegal.catch";
  
      /** Illegal class names. */
      private final Set<String> illegalClassNames = Arrays.stream(new String[] {"Exception", "Error",
          "RuntimeException", "Throwable", "java.lang.Error", "java.lang.Exception",
          "java.lang.RuntimeException", "java.lang.Throwable", }).collect(Collectors.toSet());
  
      /**
       * Set the list of illegal classes.
       *
       * @param classNames
       *            array of illegal exception classes
       */
      public void setIllegalClassNames(final String... classNames) {
          illegalClassNames.clear();
          illegalClassNames.addAll(
                  CheckUtil.parseClassNames(classNames));
      }
  
      @Override
      public int[] getDefaultTokens() {
          return getRequiredTokens();
      }
  
      @Override
      public int[] getRequiredTokens() {
          return new int[] {TokenTypes.LITERAL_CATCH};
      }
  
      @Override
      public int[] getAcceptableTokens() {
          return getRequiredTokens();
      }
  
      @Override
      public void visitToken(DetailAST detailAST) {
          final DetailAST parameterDef =
              detailAST.findFirstToken(TokenTypes.PARAMETER_DEF);
          final DetailAST excTypeParent =
                  parameterDef.findFirstToken(TokenTypes.TYPE);
          final List<DetailAST> excTypes = getAllExceptionTypes(excTypeParent);
  
          for (DetailAST excType : excTypes) {
              final FullIdent ident = FullIdent.createFullIdent(excType);
  
              if (illegalClassNames.contains(ident.getText())) {
                  log(detailAST, MSG_KEY, ident.getText());
              }
          }
      }
  
      /**
       * Finds all exception types in current catch.
       * We need it till we can have few different exception types into one catch.
      * @param parentToken - parent node for types (TYPE or BOR)
      * @return list, that contains all exception types in current catch
      */
     private static List<DetailAST> getAllExceptionTypes(DetailAST parentToken) {
         DetailAST currentNode = parentToken.getFirstChild();
         final List<DetailAST> exceptionTypes = new LinkedList<>();
         if (currentNode.getType() == TokenTypes.BOR) {
             exceptionTypes.addAll(getAllExceptionTypes(currentNode));
             currentNode = currentNode.getNextSibling();
             if (currentNode != null) {
                 exceptionTypes.add(currentNode);
             }
         }
         else {
             exceptionTypes.add(currentNode);
             currentNode = currentNode.getNextSibling();
             while (currentNode != null) {
                 exceptionTypes.add(currentNode);
                 currentNode = currentNode.getNextSibling();
             }
         }
         return exceptionTypes;
     }
 
 }