/*
    * SPDX-FileCopyrightText: Copyright (c) 2011-2026 Yegor Bugayenko
    * SPDX-License-Identifier: MIT
    */
   package com.qulice.checkstyle;
   
   import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
   import com.puppycrawl.tools.checkstyle.api.DetailAST;
   import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  
  /**
   * Forbids nested {@code switch} statements.
   *
   * <p>A {@code switch} inside another {@code switch} hides flow of control
   * behind two levels of branching and almost always signals that the enclosing
   * method is doing too much. Extract the inner statement into its own method
   * instead. Mirrors Checkstyle's built-in {@code NestedIfDepth},
   * {@code NestedForDepth} and {@code NestedTryDepth} modules.</p>
   *
   * @since 0.24
   */
  public final class NestedSwitchCheck extends AbstractCheck {
  
      /**
       * Default constructor.
       */
      public NestedSwitchCheck() {
          // nothing to initialize
      }
  
      @Override
      public int[] getDefaultTokens() {
          return this.getRequiredTokens();
      }
  
      @Override
      public int[] getAcceptableTokens() {
          return this.getRequiredTokens();
      }
  
      @Override
      public int[] getRequiredTokens() {
          return new int[] {TokenTypes.LITERAL_SWITCH};
      }
  
      @Override
      public void visitToken(final DetailAST ast) {
          DetailAST parent = ast.getParent();
          while (parent != null) {
              if (parent.getType() == TokenTypes.LITERAL_SWITCH) {
                  this.log(ast.getLineNo(), "Nested switch statements are not allowed");
                  break;
              }
              parent = parent.getParent();
          }
      }
  }