content: /*
   * This file is a part of BSL Language Server.
   *
   * Copyright (c) 2018-2025
   * Alexey Sosnoviy <labotamy@gmail.com>, Nikita Fedkin <nixel2007@gmail.com> and contributors
   *
   * SPDX-License-Identifier: LGPL-3.0-or-later
   *
   * BSL Language Server 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 3.0 of the License, or (at your option) any later version.
   *
   * BSL Language Server 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 BSL Language Server.
   */
  package com.github._1c_syntax.bsl.languageserver.diagnostics;
  
  import com.github._1c_syntax.bsl.languageserver.diagnostics.metadata.DiagnosticMetadata;
  import com.github._1c_syntax.bsl.languageserver.diagnostics.metadata.DiagnosticSeverity;
  import com.github._1c_syntax.bsl.languageserver.diagnostics.metadata.DiagnosticTag;
  import com.github._1c_syntax.bsl.languageserver.diagnostics.metadata.DiagnosticType;
  import com.github._1c_syntax.bsl.languageserver.utils.Trees;
  import com.github._1c_syntax.bsl.languageserver.utils.expressiontree.BinaryOperationNode;
  import com.github._1c_syntax.bsl.languageserver.utils.expressiontree.BslExpression;
  import com.github._1c_syntax.bsl.languageserver.utils.expressiontree.BslOperator;
  import com.github._1c_syntax.bsl.languageserver.utils.expressiontree.ExpressionNodeType;
  import com.github._1c_syntax.bsl.languageserver.utils.expressiontree.UnaryOperationNode;
  
  @DiagnosticMetadata(
    type = DiagnosticType.CODE_SMELL,
    severity = DiagnosticSeverity.MAJOR,
    minutesToFix = 3,
    tags = {
      DiagnosticTag.BRAINOVERLOAD,
      DiagnosticTag.BADPRACTICE
    }
  )
  public class DoubleNegativesDiagnostic extends AbstractExpressionTreeDiagnostic {
  
    @Override
    protected void visitBinaryOperation(BinaryOperationNode node) {
  
      if (node.getOperator() != BslOperator.EQUAL && node.getOperator() != BslOperator.NOT_EQUAL) {
        super.visitBinaryOperation(node);
        return;
      }
  
      var parent = node.getParent();
  
      if (parent == null || !isNegationOperator(parent)) {
        super.visitBinaryOperation(node);
        return;
      }
  
      if (node.getOperator() == BslOperator.NOT_EQUAL) {
        addDiagnostic(node);
      }
  
      super.visitBinaryOperation(node);
    }
  
    @Override
    protected void visitUnaryOperation(UnaryOperationNode node) {
      if (node.getOperator() == BslOperator.NOT &&
        node.getParent() != null &&
        node.getParent().getNodeType() == ExpressionNodeType.UNARY_OP) {
  
        var unaryParent = node.getParent().<UnaryOperationNode>cast();
        if (unaryParent.getOperator() == BslOperator.NOT) {
          addDiagnostic(node);
        }
      }
  
      super.visitUnaryOperation(node);
    }
  
    private static boolean isNegationOperator(BslExpression parent) {
      return parent.getNodeType() == ExpressionNodeType.UNARY_OP
        && parent.<UnaryOperationNode>cast().getOperator() == BslOperator.NOT;
    }
  
    private void addDiagnostic(BinaryOperationNode node) {
      var startToken = Trees.getTokens(node.getParent().getRepresentingAst())
        .stream()
        .findFirst()
        .orElseThrow();
  
      var endToken = Trees.getTokens(node.getRight().getRepresentingAst())
        .stream()
        .reduce((one, two) -> two)
        .orElseThrow();
  
      diagnosticStorage.addDiagnostic(startToken, endToken);
    }
  
    private void addDiagnostic(UnaryOperationNode node) {
      var startToken = Trees.getTokens(node.getParent().getRepresentingAst())
        .stream()
        .findFirst()
        .orElseThrow();
  
      var endToken = Trees.getTokens(node.getOperand().getRepresentingAst())
        .stream()
        .reduce((one, two) -> two)
        .orElseThrow();
  
      diagnosticStorage.addDiagnostic(startToken, endToken);
    }
  }
  