///////////////////////////////////////////////////////////////////////////////////////////////
   // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
   // Copyright (C) 2001-2026 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.modifier;
  
  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.Scope;
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  import com.puppycrawl.tools.checkstyle.utils.ScopeUtil;
  
  /**
   * <div>
   * Checks for implicit modifiers on nested types in classes and records.
   * </div>
   *
   * <p>
   * This check is effectively the opposite of
   * <a href="https://checkstyle.org/checks/modifier/redundantmodifier.html">
   * RedundantModifier</a>.
   * It checks the modifiers on nested types in classes and records, ensuring that certain modifiers
   * are explicitly specified even though they are actually redundant.
   * </p>
   *
   * <p>
   * Nested enums, interfaces, and records within a class are always {@code static} and as such the
   * compiler does not require the {@code static} modifier. This check provides the ability to enforce
   * that the {@code static} modifier is explicitly coded and not implicitly added by the compiler.
   * </p>
   * <div class="wrapper"><pre class="prettyprint"><code class="language-java">
   * public final class Person {
   *   enum Age {  // violation
   *     CHILD, ADULT
   *   }
   * }
   * </code></pre></div>
   *
   * <p>
   * Rationale for this check: Nested enums, interfaces, and records are treated differently from
   * nested classes as they are only allowed to be {@code static}. Developers should not need to
   * remember this rule, and this check provides the means to enforce that the modifier is coded
   * explicitly.
   * </p>
   *
   * @since 8.16
   */
  @StatelessCheck
  public class ClassMemberImpliedModifierCheck
      extends AbstractCheck {
  
      /**
       * A key is pointing to the warning message text in "messages.properties" file.
       */
      public static final String MSG_KEY = "class.implied.modifier";
  
      /** Name for 'static' keyword. */
      private static final String STATIC_KEYWORD = "static";
  
      /**
       * Control whether to enforce that {@code static} is explicitly coded
       * on nested enums in classes and records.
       */
      private boolean violateImpliedStaticOnNestedEnum = true;
  
      /**
       * Control whether to enforce that {@code static} is explicitly coded
       * on nested interfaces in classes and records.
       */
      private boolean violateImpliedStaticOnNestedInterface = true;
  
      /**
       * Control whether to enforce that {@code static} is explicitly coded
       * on nested records in classes and records.
       */
      private boolean violateImpliedStaticOnNestedRecord = true;
  
      /**
       * Creates a new {@code ClassMemberImpliedModifierCheck} instance.
       */
      public ClassMemberImpliedModifierCheck() {
          // no code by default
      }
 
     /**
      * Setter to control whether to enforce that {@code static} is explicitly coded
      * on nested enums in classes and records.
      *
      * @param violateImplied
      *        True to perform the check, false to turn the check off.
      * @since 8.16
      */
     public void setViolateImpliedStaticOnNestedEnum(boolean violateImplied) {
         violateImpliedStaticOnNestedEnum = violateImplied;
     }
 
     /**
      * Setter to control whether to enforce that {@code static} is explicitly coded
      * on nested interfaces in classes and records.
      *
      * @param violateImplied
      *        True to perform the check, false to turn the check off.
      * @since 8.16
      */
     public void setViolateImpliedStaticOnNestedInterface(boolean violateImplied) {
         violateImpliedStaticOnNestedInterface = violateImplied;
     }
 
     /**
      * Setter to control whether to enforce that {@code static} is explicitly coded
      * on nested records in classes and records.
      *
      * @param violateImplied
      *        True to perform the check, false to turn the check off.
      * @since 8.36
      */
     public void setViolateImpliedStaticOnNestedRecord(boolean violateImplied) {
         violateImpliedStaticOnNestedRecord = violateImplied;
     }
 
     @Override
     public int[] getDefaultTokens() {
         return getAcceptableTokens();
     }
 
     @Override
     public int[] getRequiredTokens() {
         return getAcceptableTokens();
     }
 
     @Override
     public int[] getAcceptableTokens() {
         return new int[] {
             TokenTypes.INTERFACE_DEF,
             TokenTypes.ENUM_DEF,
             TokenTypes.RECORD_DEF,
         };
     }
 
     @Override
     public void visitToken(DetailAST ast) {
         if (isInTypeBlock(ast)) {
             final DetailAST modifiers = ast.findFirstToken(TokenTypes.MODIFIERS);
             switch (ast.getType()) {
                 case TokenTypes.ENUM_DEF -> {
                     if (violateImpliedStaticOnNestedEnum
                             && modifiers.findFirstToken(TokenTypes.LITERAL_STATIC) == null) {
                         log(ast, MSG_KEY, STATIC_KEYWORD);
                     }
                 }
 
                 case TokenTypes.INTERFACE_DEF -> {
                     if (violateImpliedStaticOnNestedInterface
                             && modifiers.findFirstToken(TokenTypes.LITERAL_STATIC) == null) {
                         log(ast, MSG_KEY, STATIC_KEYWORD);
                     }
                 }
 
                 case TokenTypes.RECORD_DEF -> {
                     if (violateImpliedStaticOnNestedRecord
                             && modifiers.findFirstToken(TokenTypes.LITERAL_STATIC) == null) {
                         log(ast, MSG_KEY, STATIC_KEYWORD);
                     }
                 }
 
                 default -> throw new IllegalStateException(ast.toString());
             }
         }
     }
 
     /**
      * Checks if ast is in a class, enum, anon class or record block.
      *
      * @param ast the current ast
      * @return true if ast is in a class, enum, anon class or record
      */
     private static boolean isInTypeBlock(DetailAST ast) {
         return ScopeUtil.isInScope(ast, Scope.ANONINNER)
                 || ScopeUtil.isInClassBlock(ast)
                 || ScopeUtil.isInEnumBlock(ast)
                 || ScopeUtil.isInRecordBlock(ast);
     }
 
 }