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.DiagnosticScope;
  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.parser.BSLLexer;
  import com.github._1c_syntax.bsl.parser.BSLParser;
  import com.github._1c_syntax.bsl.parser.BSLParserRuleContext;
  import org.antlr.v4.runtime.Token;
  import org.antlr.v4.runtime.misc.IntervalSet;
  import org.antlr.v4.runtime.tree.ErrorNode;
  import org.antlr.v4.runtime.tree.ErrorNodeImpl;
  import org.antlr.v4.runtime.tree.TerminalNodeImpl;
  
  import java.util.StringJoiner;
  import java.util.stream.IntStream;
  
  @DiagnosticMetadata(
    type = DiagnosticType.ERROR,
    severity = DiagnosticSeverity.CRITICAL,
    scope = DiagnosticScope.ALL,
    minutesToFix = 5,
    tags = {
      DiagnosticTag.ERROR
    }
  )
  public class ParseErrorDiagnostic extends AbstractListenerDiagnostic {
  
    public static final int EOF = -1;
  
    @Override
    public void visitErrorNode(ErrorNode node) {
  
      if (((ErrorNodeImpl) node).symbol.getTokenIndex() == -1) {
        diagnosticStorage.addDiagnostic(
          ((BSLParserRuleContext) node.getParent()).getStart(),
          info.getMessage(node.getText())
        );
      }
    }
  
    @Override
    public void enterFile(BSLParser.FileContext ctx) {
      BSLParser.FileContext ast = this.documentContext.getAst();
      String initialExpectedString = info.getResourceString("expectedTokens") + " ";
  
      Trees.getDescendants(ast).stream()
        .filter(parseTree -> !(parseTree instanceof TerminalNodeImpl))
        .map(parseTree -> (BSLParserRuleContext) parseTree)
        .filter(node -> node.exception != null)
        .forEach((BSLParserRuleContext node) -> {
          IntervalSet expectedTokens = node.exception.getExpectedTokens();
          StringJoiner sj = new StringJoiner(", ");
          expectedTokens.getIntervals().stream()
            .flatMapToInt(interval -> IntStream.range(interval.a, interval.b))
            .mapToObj(ParseErrorDiagnostic::getTokenName)
            .forEachOrdered(sj::add);
  
          Token errorToken = node.exception.getOffendingToken();
          if (errorToken.getType() == EOF) {
            errorToken = node.getStart();
          }
  
          diagnosticStorage.addDiagnostic(
            errorToken,
            info.getMessage(initialExpectedString + sj)
          );
        });
    }
  
    private static String getTokenName(int tokenType) {
      String value = BSLLexer.VOCABULARY.getLiteralName(tokenType);
      if (value == null) {
        value = BSLLexer.VOCABULARY.getSymbolicName(tokenType);
      }
  
      return value;
    }
  }
  